Ahn, J., Lovingshimer, M., Salzman, R., Presnall, J., Lu, A., Koiwa, H., and Zhu-Salzman, K., Cowpea bruchid Callosobruchus machulatus contereracts dietary protease inhibitors through modulating propeptides of major digestive enzymes, Insect Mol. Biol., 2007, 16:295-304 |
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Cowpea bruchids, when challenged by consumption of the soybean cysteine protease inhibitor scN, reconfigure expression of their major CmCP digestive proteases and resume normal feeding and development. Previous evidence indicated that insects selectively induced CmCPs from subfamily B, that were more efficient in autoprocessing and possessed not only higher proteolytic, but also scN-degrading activities. In contrast, dietary scN only marginally up-regulated genes from the more predominant CmCP subfamily A that were inferior to subfamily B. To gain further molecular insight into this adaptive adjustment, we performed domain swapping between the two respective subfamily members B1 and A16, the latter unable to autoprocess or degrade scN even after intermolecular processing. Swapping the propeptides did not qualitatively alter autoprocessing in either protease isoform. Incorporation of either the N- (pAmBA) or C-terminal (pAmAB) mature B1 segment into A16, however, was sufficient to prime autoprocessing of A16 to its mature form. Further, the swap at the N-terminal mature A16 protein region (pAmBA) resulted in four amino acid changes. Replacement of these amino acid residues by the corresponding B1 residues, singly and pair-wise, revealed that autoprocessing activation in pAmBA resulted from cumulative and/or coordinated individual effects. Bacterially expressed isolated propeptides (pA16 and pB1) differed in their ability to inhibit mature B1 enzyme. Lower inhibitory activity in pB1 is likely attributable to its lack of protein stability. This instability in the cleaved propeptide is necessary, although insufficient by itself, for scN-degradation by the mature B1 enzyme. Taken together, cowpea bruchids modulate proteolysis of their digestive enzymes by controlling poCmCP cleavage and propeptide stability, which explains at least in part the plasticity cowpea bruchids demonstrate in response to protease inhibitors.
Non Technical Summary |
| Ahn, J.., Guarino, L., and Zhu-Salzman, K., Seven-up facilitates insect counter-defense by suppressing cathepsin B expression., FEBS J, 2007, 274:2800-2814 |
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When challenged by the dietary soybean cysteine protease inhibitor scN, the cowpea bruchid (Callosobruchus maculatus) adapts to the inhibitory effects by readjusting the transcriptome of its digestive system, including the specific activation of a cathepsin B-like cysteine protease CmCatB. To understand the transcriptional regulation of CmCatB, we cloned a portion of its promoter and demonstrated its activity in Drosophila cells using a chloramphenicol acetyltransferase reporter system. EMSAs detected differential DNA-binding activity between nuclear extracts of scN-adapted and -unadapted midguts. Two tandem chicken ovalbumin upstream promoter (COUP) elements were identified in the CmCatB promoter that specifically interacted with a protein factor unique to nuclear extracts of unadapted insect guts, where CmCatB expression was repressed. Seven-up (Svp) is a COUP-TF-related transcription factor that interacted with the COUP responsive element. Polyclonal anti-(mosquito Svp) serum abolished the specific DNA-binding activity in cowpea bruchid midgut extracts, suggesting that the protein factor is an Svp homolog. Subsequent cloning of a cowpea bruchid Svp (CmSvp) indicated that it shares a high degree of amino acid sequence similarity with COUP-TF/ Svp orphan nuclear receptor family members from varied species. The protein was more abundant in scN-unadapted insect guts than scN-adapted guts, consistent with the observed DNA-binding activity. Furthermore, CmCatB expression was repressed when CmSvp was transiently expressed in Drosophila cells, most likely through COUP binding. These findings indicate that CmSvp may contribute to insect counter-defense, in part by inhibiting CmCatB expression under normal growth conditions, but releasing the inhibition when insects are challenged by dietary protease inhibitors.
Non Technical Summary |
| Amirhusin, B., Shade, R., Koiwa, H., Hasegawa, P., Bressan, R., Murdock, R.., and Zhu-Salzman, K., Protease inhibitors from several classes work synergistically against Callosobruchus maculates, Journal of Insect Physiology, 2007, 53:734-740 |
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Targeting multiple digestive proteases may be more effective in insect pest control than inhibition of a single enzyme class. We therefore explored possible interactions of three antimetabolic protease inhibitors fed to cowpea bruchids in artificial diets, using a recombinant soybean cysteine protease inhibitor scN, an aspartic protease inhibitor pepstatin A, and soybean Kunitz trypsin inhibitor KI. scN and pepstatin, inhibiting major digestive cysteine and aspartic proteases, respectively, significantly prolonged the developmental time of cowpea bruchids individually. When combined, the anti-insect effect was synergistic, i.e., the toxicity of the mixture was markedly greater than that of scN or pepstatin alone. KI alone did not impact insect development even at relatively high concentrations, but its anti-insect properties became apparent when acting jointly with scN or scN plus pepstatin. Incubating KI with bruchid midgut extract showed that it was partially degraded. This instability may explain its lack of anti-insect activity. However, this proteolytic degradation was inhibited by scN and/or pepstatin. Protection of KI from proteolysis in the insect digestive tract thus could be the basis for the synergistic effect. These observations support the concept that cowpea bruchid gut proteases play a dual role; digesting protein for nutrient needs and protecting insects by inactivating dietary proteins that may otherwise be toxic. Our results also suggest that transgenic resistance strategies that involve multigene products are likely to have enhanced efficacy and durability.
Non Technical Summary |
| Bang, H., Kim, S., Leskovar, D., and King, S., Development of a Codominant CAPS Marker for Allelic Selection Between Canary Yellow and Red Watermelon Based on SNP in Lycopene B-cyclase (LCYB) Gene, Molecular Breeding, 2007, 20:63-72 |
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Flesh color of watermelon is an agronomically important trait that is predominantly determined by a network of the carotenoid biosynthetic pathway, which also contributes to the nutritional value of the fruit through the health-promoting function of carotenoids. We have identified a key gene, lycopene b-cyclase (LCYB) that may determine canary yellow and red flesh color of watermelon and developed a zero-distance molecular marker that identifies a critical single nucleotide polymorphism (SNP) that distinguishes different alleles of the LCYB gene. Analysis of the flesh color inheritance in segregating populations indicated that a single gene determines the color difference between canary yellow and red flesh in watermelon. The sequence comparison of full-length cDNA of LCYB, which was isolated using degenerate PCR and RACE, identified three SNPs in the coding region of LCYB between canary yellow and red. These SNPs showed perfect co-segregation with flesh color phenotypes. One of the SNPs introduces an amino acid replacement of evolutionarily conserved Phe226 to Val, which may impair the catalytic function of LCYB. This SNP was used to develop a cleaved amplified polymorphic sequence (CAPS) marker, which perfectly cosegregated with flesh color phenotype. Our results strongly suggest that LCYB may be the genetic determinant for canary yellow or red flesh color and our CAPS marker will allow breeders to economically distinguish between canary yellow and red watermelon fruit color at the seedling stage.
Non Technical Summary |
| Chapkin, R., McMurray, D., and Lupton, J., Colon cancer, fatty acids and anti-inflammatory compounds., Current Opinion in Gastroenterology, 2007, 23:48-54 |
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Purpose of review: To outline recent findings on the efficacy of n-3 polyunsaturated fatty acids in the prevention/treatment of inflammatory bowel disease and colorectal cancer. Recent findings: Compelling data indicate a functional link between chronic inflammation and colon cancer. With respect to environmental risk factors, there is growing evidence that long-chain n-3 polyunsaturated fatty acids found in fish oil suppress inflammatory bowel diseases and colon cancer risk in humans. Unfortunately, the molecular basis of the effect of n-3 polyunsaturated fatty acids on inflammation/colitis-associated colon cancer risk is still largely obscure in this review, we focus on recent studies which address three emerging mechanisms of n-3 polyunsaturated fatty acids action: (1) metabolic interconversion into bioactive eicosanoids, (2) modulation of nuclear receptor activation, and (3) alteration of membrane phospholipids composition and functionality of lipid microdomains. Summary: The consumption of dietary fish oil may prove to be an effective adjuvant therapy in colon cancer. Therefore, it is both appropriate and timely to determine precisely how n-3 polyunsaturated fatty acids modulate cell signaling networks, and reduce the risk of developing colon cancer and inflammatory disorders of the intestine.
Non Technical Summary |
| Chapkin, R., Davidson, L., Ly, L., Weeks, B., Lupton, J., and McMurray, D., Immunomodulatory Effects of (n-3) Fatty Acids: Putative link to Inflammation and Colon Cancer., Journal of Nutrition, 2007, 137:200S-204S |
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Chronic inflammation and colorectal cancer are closely linked. Although the overall mechanisms of inflammation-associated gastrointestinal carcinogenesis are complex, it is clear that antiflammatory therapy is efficacious against neoplastic progression and malignant conversion. From a dietary perspective, fish oil contain (n-3) polyunsaturated fatty acids (PUFSs) has antinflammatory properties, but for years that mechanism has remained obscure. Of relevance to the immune system in the intestine, we showed that (n-3) PUFA feeding alters the balance between CD4+ T-helper (Th1 and Th2) subsets by directly suppressing Th1 cell development (i.e., clonal expansion). This is noteworthy because Th1 cells mediate inflammatory diseases and resistance to intracellular pathogens or allergic hypersensitivity, and Th2 cells mediate resistance to extracelluar pathogens. Therefore, any changes induced by (n-3) PUFAs in T-cell subset balance and function are important because the outcome is expected to suppress the development of autoimmune diseases and possibly the occurrence of colon cancer. Precisely how the immonomodulatory effects of (n-3) PUFAs influence inflammation-associated colonic tumor development is the subject of an ongoing investigation.
Non Technical Summary |
| Davis, A. and King, S., MSW-28, a Full-flavor Crisp Watermelon Line with High Lycopene and Medium Brix, 2007, HortScience 42(7) December 2007:1715-1716 |
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The Agricultural Research Service of the U. S. Department of Agriculture announces the release of MSW-28, a watermelon [Citrullus lanatus var. Ianatus (Thumb.) Matsum. & Nakal)] line that exhibits medium sugar content (brix) and full flavor of heirloom varieties combined with the lycopene content and crip texture of modern cultivars. Most heirloom cultivars of watermelon have a full flavor but typically lower sugar content compared with modern cultivars. Many people report a preference for heirloom varieties, citing flavor as the primary reason. Unfortunately, heirloom varieties often have low yield, poor disease resistance, and inferior flesh texture and quality. Increasing fruit sugar content has been a priority of many breeding programs, and the sugar content of modern watermelon cultivars is considerably higher than their heirloom counterparts. It is estimated that there are 20.8 million people in the United States with diabetes (Centers for Disease Control and Prevention, 2005). Watermelon is considered a high-glycemic food (Foster-Powell et al., 2002), but a good source of lycopene (Perkins-Vizier et al., 2006), vitamin A, and potassium (U. S. Department of Agriculture, Agricultural Research Service, 2006). The goal of this research was to develop a watermelon variety adapted to modern farming practices that has a firm rind; firm, crisp, full-flavored high lycopene flesh with small funiculus; and a moderate brix for consumers interested in fully flavored, lower sugar fruit.
Non Technical Summary |
| Deyhim, F., Patil, B., Villarreal, A., Lopez, E., Garcia, K., Rios, R., Garcia, C., Gonzales, C., and Mandadi, K., Cranberry Juice Increases Antioxidant Status Without Affecting Cholesterol Homeostasis In Orchidectomized Rats., 2007, Journal of Medicinal Food 10:49-53 |
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Oxidative stress and hypogonadism are linked to the increased incidence of cardiovascular disease in males. The objective of this research was to delineate whether drinking cranberry juice for 4 months affects antioxidant capacity and lipid profile in orchidectomized rats. Thirty-two 1-year-old male rats were randomized to two groups: a sham-control group (n = 8) and an orchidectomized group (n = 24). The orchidectomized group was divided into three groups of eight and assigned to one of the following treatments: orchidectomy, orchidectomy plus 27% cranberry juice, and orchidectomy plus 45% cranberry juice. At 120 days after initiation of the study, all rats were killed, blood was collected, and plasma was harvested for total antioxidant status, malondialdehyde, nitrate + nitrite, and superoxide dismutase (SOD) activity in liver, and concentrations of cholesterol and triglyceride in liver an in plasma. Orchidectomy depressed (P < .05) plasma antioxidant capacity and SOD activity, elevated (P < .05) nitrate + nitrite and malondialdehyde in plasma, and increased (P < .05) triglyceride and cholesterol values in liver and in plasma. Cranberry juice increased (P <.05) plasma antioxidant capacity and SOD activity and reduced (P <.05) nitrate + nitrite and malondialdehyde concentrations. Drinking cranberry juice did not affect cholesterol concentrations in liver and in plasma. Triglyceride concentration in plasma of orchidectomized rats that were drinking cranberry juice increased (P < .05), but its concentration in liver decreased (P < .05) to the level of shams. The protective effect of cranberry juice from oxidative damage may be mediated by a decrease in nitrate _ nitrite and dose-dependent decrease in peroxidation.
Non Technical Summary |
| Deyhim, F., Rios, R., Villarreal, A., Garcia, C., Garcia, K., Mandadi, K., Gonzales, C., Faraji, B., and Patil, B., Orange pulp Increases Antioxidant Status and Improves Bone Quality in Orchidectomized Rats, Current Nutrition and Food Science, 2007, 3:319-323 |
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An experiment was conducted to evaluate the effect of feeding orange pulp on plasma antioxidant status and bone quality in orchidectomized rats. Forty-five one-year-old male rats were randomly placed in a sham-control group and four orchidectomized groups. Orchidectomized rates were assigned to one of the following treatments: orchidectomy (ORX), ORX+2.5% orange pulp (OP); ORX+5 +5.0% OP; ORX+q0.0% OP. Four months after the study began, all rats were killed, blood was collected, and the plasma was harvested for antioxidant status and IGF-I. Orchidectomy did not (P > 0.1) affect red blood cell hemolysis percentage, but decreased (P < 0.05) the plasma IGF-I concentration, bone density, femoral strength, time induced femoral fracture, calcium and magnesium concentrations in the femur and the 5” lumbar, and increased (P < 0.05) urinary deoxpyridinoline, calcium and magnesium excretions compared to the sham group. Feeding 2.5% OP tended to increase IGF-I and increased (P < 0.05) improved antioxidant status by protecting red blood cells against hemolysis, increased (P M 0.05) the plasma IGF-I, bone density and bone mineral content, and decreased (P < 0.05) urinary magnesium excretion and urinary deoxyridinoline concentration. In conclusion, orange pulp significantly affects bone quality by enhancing calcium and magnesium deposition in bones and by showing-down born turnover rate.
Non Technical Summary |
| Deyhim, F., Villarreal, A., Garcia, K., Rios, C., Garcia, C., Gonzales, C., Mandadi, K., and Patil, B., Orange Pulp Improves Antioxidant Status And Suppresses Lipid Peroxidation In Orchidectomized Rats., Nutrition, 2007, 23:617-621 |
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Objective: Oxidative stress is linked to an increased incidence of cardiovascular disease in men. The objective of this research was to delineate whether daily consumption of orange pulp (OP) modifies antioxidant status and decreases cardiovascular risk factors in orchidectomized rats. Methods: In the present study, 45 1-y-old male rats were randomized to a sham-control group (n = 9) and an orchidectomized group (n = 36). The orchidectomized group was equally divided among the following five treatments: orchidectomy (ORX), ORX ÷ 2.5% OP, ORX + 5% OP, and ORX + 10% OP. One hundred twenty days after the study began, all rats were sacrificed and plasma was harvested for its antioxidant status, C-reactive protein (CRP), lipid profile, and indices of peroxidation. Superoxide dismutase (SOD) and catalase activities in the liver were also monitored. Results: Orchidectomy decreased (P < 0.05) plasma levels of antioxidant, SOD, catalase, and CRP and increased (P < 0.05) plasma levels of malondialdehyde, nitrite, and lipid profile compared with the sham-control group. In contrast to ORX, ORX + OP increased (P < 0.05) plasma antioxidant, dose-dependently increased (P < 0.05) SOD and catalase, decreased (P < 0.05) plasma malondialdehyde, nitrite, cholesterol, and triacylglycerol concentrations in the liver; and had no effect (P > 0.1) on plasma CRP or lipid profiles. Conclusion: The beneficial effect of eating an orange is demonstrated by the increasing antioxidant status and by the decreasing peroxidation independent of plasma triacylglycerol, cholesterol, or CRP concentrations.
Non Technical Summary |
| Deyhim, F., Gonzales, C., Garcia, C., Villarreal, A., Garcia, K., Rios, R., Mandadi, K., and Patil, B., Vitamin E Does Not Modulate Plasma Lipid Profile or C-Reactive Protein Despite Suppressing Oxidative Stress in Orchiectomized Rats, Journal of Medicinal Food, 2007, 10(3) 2007:559-562 |
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Vitamin E is known to improve antioxidant status and to prevent lipoprotein oxidation. However, the effect of vitamin E on other cardiovascular risk factors, including C-reactive protein (CRP) and lipid profile status, in orchiectomized rates is unknown. In the present study, 32 1-year-old male rats were randomized into two groups: a sham-control group (n – 8) and an orchiectomized group (n = 24). The orchiectomized group was divided into three groups of eight and assigned to one of the following treatments: orchiectomy (ORX), ORX + vitamin E mixture (65.6 mg/kg) diet, or ORX + vitamin E mixture 656 mg/kg) diet. For 120 days all four groups consumed a basal AIN-93M diet, while the E groups ate diets containing an additional vitamin E mixture. Four months after the study began, all the rats were killed, the blood was collected, and the plasma was assayed for antioxidant status, CRP, lipid profile, and indices of peroxidation. ORX decreased (P < .05) the plasma antioxidant status, superoxide dismutase (SOD) activity, and CRP level and increased (P < .05) the plasma malondialdeyde, nitrite, and lipid profile compared with that of the sham-control group. In contrast to the ORX group, supplementation with vitamin E mixture increased (P < .05) plasma antioxidant status and dose-dependently increased j(P < .05) SOD activity, while the vitamin E decreased (P < .05) plasma malondialdeyde and nitrate. The vitamin E mixture had no effect on CRP or on lipid profiles when compared to the orchiectomized rats. In conclusion, vitamin E appears to reduce oxidative stress without modulating lipid profile or inflammatory response.
Non Technical Summary |
| Deyhim, F., Garcia, C., Villarreal, A., Garcia, K., Rios, R., Gonzales, C., Mandadi, K., Faraji, B., and Patil, B., Vitamin E does not Support Bone Quality in Orchidectomized Rats, Current Nutrition and Food Science, 2007, 3:300-303 |
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Vitamin E is known to improve antioxidant status and to prevent lipoprotein oxidation. However, the effect of vitamin E on other cardiovascular risk factors, including C-reactive protein (CRP) and lipid profile status, in orchiectomized rats is unknown. In the present study, 32 1-year-old male rats were randomized into two groups: a sham-control group (n = 8) and an orchiectomized group (n = 24). The orchiectomized group was divided into three groups of eight and assigned to one of the following treatments: orchiectomy (ORX), ORX + vitamin E mixture (65.6 mg/kg) diet, or ORX + vitamin E mixture (656 mg/kg) diet. For 120 days all four groups consumed a basal AIN-93M diet, while the vitamin E groups ate diets containing an additional vitamin E mixture. Four months after the study began, all the rats were killed, the blood was collected, and the plasma was assayed for antioxidant status, CRP, lipid profile, and indices of peroxidation. ORX decreased (P < .05) the plasma antioxidant status, superoxide dismutase (SOD) activity, and CRP level and increased (P < .05) the plasma malondialdeyde, nitrite, and lipid profile compared with that of the sham-control group. In contrast to the ORX group, supplementation with vitamin E mixture increased (P < .05) plasma antioxidant status and dose-dependently increased (P < .05) SOD activity, while the vitamin E decreased (P < .05) plasma malondialdeyde and nitrite. The vitamin E mixture had no effect on CRP or on lipid profiles when compared to the orchiectomized rats. In conclusion, vitamin E appears to reduce oxidative stress without modulating lipid profile or inflammatory response.
Non Technical Summary |
| Falkenberg, N., Piccinni, G., Cothren, J., Leskovar, D., and Rush, C., Remote sensing of biotic and abiotic stress for irrigation management of cotton, Agricultural Water Management, 2007, 87:23031 |
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The applicability of commercially available remote sensing instrumentation was evaluated for site-specific management of abiotic and biotic stress on cotton (Gossypium hirsutum L.) grown under a center pivot low energy precision application (LEPA) irrigation system. This study was conducted in a field where three irrigation regimes (100%, 75%, and 50% ETc) were imposed on areas of Phymatotrichum (root rot) with the specific objectives to (1) examine commercial remote sensing instrumentation for locating areas showing biotic and abiotic stress symptomology in a cotton field, (2) compare data obtained from commercial aerial infrared photography to that collected by infrared transducers (IRTs) mounted on a center pivot, (3) evaluate canopy temperature changes between irrigation regimes and their relationship to lint yield with IRTs and/or IR photography, and (4) explore the use of deficit irrigation and the use of crop coefficients for irrigation scheduling. Pivot-mounted IRTs and an IR camera were able to differentiate water stress among irrigation regimes. The IR camera distinguished between biotic (root rot) and abiotic (drought) stress with the assistance of groundtruthing. The 50% ETc regime had significantly higher canopy temperatures than the other two regimes, which was reflected in significantly lower lint yields when compared to the 75% and 100% ETc regimes. Deficit irrigation down to 75% ETc had no impact on lint yield, indicating that water savings were possible without reducing yield. # 2006 Elsevier B.V. All rights reserved.
Non Technical Summary |
| Falkenberg, N., Piccinni, G., Cothren, J., Leskovar, D., and Rush, C., Vitamin E improves antioxicant status and suppresses lipid peroxidation but has no effect on C-reactive protein concentration., 2007, Journal of Medicinal Food 10(3):559-562 |
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Vitamin E is known to improve antioxidant status and to prevent lipoprotein oxidation. However, the effect of vitamin E on other cardiovascular risk factors, including C-reactive protein (CRP) and lipid profile status, in orchiectomized rats is unknown. In the present study, 32 1-year-old male rats were randomized into groups: a sham-control group (n – 8) and an orchiectemoized group (n = 24). The orchiectomized group was divided into three groups of eight and assigned to one of the following treatments: orchiectomy (ORX), ORX ¸ vitamin E mixture (65.6 mg/kg) diet, or X ¸ vitamin E mixture (656 mg/kg) diet. For 120 days all four groups consumed a basal AIN-93M diet, while the vitamin E group ate diets containing an additional vitamin E mixture. Four months, after the study began, all the rats were killed, the blood was collected, and the plasma was assayed for antioxidant status, CRP, lipid profile, and indices of peroxidation. ORX decreased (P _ .05) the plasma antioxidant status, superoxide dismutase (SOD) activity, and CRP level and increased (P _ .05) the plasma malondialdeyde, nitrite, and lipid profile compared with that of the sham-control group. In contrast to the ORX group, supplementation with vitamin E mixture increased (P _ .05) plasma antioxidant status and dose-dependently increased (P _ .05) SOD activity, while the vitamin E decreased (P _ .05) plasma malondialdeyde and nitrite. The vitamin E mixture had no effect on CRP or on lipid profiles when compared to the orchiectomized rats. In conclusion, vitamin E appears to reduce oxidative stress without modulating lipid profile or inflammatory response.
Non Technical Summary |
| Girennavar, B., Jayaprakasha, G., and Patil, B., Potent Inhibition of Human Cytochrome P450 3A4, 2D6, and 2C9 Isoenzymes by Grapefruit Juice and Its Furocoumarins, 2007, Journal of Food Science 72:1781-1785 |
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The cytochrome P450 enzyme family is the most abundant and responsible for the metabolism of more than 60% of currently marketed drugs and is considered central in many clinically important drug interactions. Seven different grapefruit and pummelo juices as well as 5 furocoumarins isolated from grapefruit juice were evaluated at different concentration on cytochrome P450 3A4 (CYP3A4), cytochrome P450 2C9 (CYP2C9), and cytochromeP450 2D6 (CYP2D6) isoenzyme activity.Grapefruit and pummelo juiceswere found to be potent inhibitors of cytochrome CYP3A4 and CYP2C9 isoenzymes at 25% concentration, while CYP2D6 is inhibited significantly low at all the tested concentration of juices (P < 0.05). Among the 5 furocoumarins tested, the inhibitory potency was in the order of paradisin A > dihydroxybergamottin > bergamottin > bergaptol > geranylcoumarin at 0.1 μMto 0.1 mMconcentrations. The IC50 valuewas lowest for paradisin A for CYP3A4 with 0.11 μMfollowed byDHBfor CYP2C9 with 1.58 μM.
Non Technical Summary |
| Girennavar, B., Jayaprakasha, G., Jadegoud, Y., Gowda, G., and Patil, B., Radical scavenging and cytochrome P450 3A4 inhibitory activity of bergaptol and Geranylcoumarin from grapefruit, Bioorganic & Medicinal Chemistry, 2007, 15:3684-3691 |
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Grapefruit juice has been shown to increase the oral bioavailability of several clinically important drugs by inhibiting first pass metabolism. Several compounds in grapefruit juice have shown different biological activities. Unique among them are furocouomarins with potent inhibitory activity against cytochrome P450 enzymes. In the present study, two bioactive compounds were isolated from grapefruit juice and grapefruit peel oil. The purity of the isolated compounds has been analyzed by HPLC. Structures of the compounds were elucidated by extensive NMR and mass spectral studies and identified as bergaptol and geranylcoumarin. The isolated compouns were tested for their radical scavenging activity using 2.2'-azobis (3-ethylbenz-thiazoline-6-sulfanic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazil (DPPH) methods at different concentrations. Bergaptol showed very good radical scavenging activity at all the tested concentrations. Furthermore, these compounds were evaluated for their inhibitory activity againstCYP3A4 enzyme. Bergaptol and geranylcoumarin were found to be potent inhibitiors of debenzylation activity of CYP3A4 enzyme with an IC50 value of 24.92 and 42.93 mM, respectively.
Non Technical Summary |
| Goreta, S., Leskovar, D., and Jifon, J., Gas Exchange, Water Status, and Growth of Pepper Seedlings Exposed to Transient Water Deficit Stress are Differentially Altered by Antitranspirants, 2007, J. Amer. Soc Hort Sci 132(5):603-610 |
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Successful field establishment of vegetable transplants often depends on the ability of young seedlings to tolerate various biotic and abiotic stresses after transplanting. Treatments that limit transpirational water loss could improve plant survival and stand establishment. In this study, we evaluated growth and physiological responses of pepper (Capsicum annuum L.) seedlings to foliar application of chemical plant regulators [abscisic acid (ABA) and aminoethoxyvinylglycine (AVG)] or physical film-forming barriers [AntiStress (AS), Transfilm (TF), and Vapor Gard (VG)] during the transient 4-day water deficient cycles. During two 4-day water deficit cycles, stomatal conductance (gs) and net CO2 assimilation rate (Aco2) were unaffected by the application of physical materials, but differed for ABA and AVG. Compared with untreated control plants, ABA reduced gs (47% to 69%) and Aco2 (37% to 57%) by the end of the second water deficit cycle, whereas AVG increased gs (27% to 60%) during the first desiccation cycle. Leaf (Ylf) and stem (Yet) xylem water potential of plants treated with film-forming materials generally decreased at athe same rate as those of untreated plants, whereas application of AVG caused earlier and more pronounced decline of Ylf. Application of ABA enabled the maintenance of Ylf and Yst during two desiccation cycles, and thus prevented an increase of electrolyte leakage and leaf abscission. Growth rates of all plant components were reduced after ABA applications. However, allometric relationships showed similar patterns of dry matter allocation in leaves and shoots among ABA, TF, VG, and untreated control plants. Application of AS reduced allocation of dry matter to leaves, whereas AVG enhanced it at the expense of roots. These data indicate that water deficit tolerance of pepper seedlings only occurred with foliar application of ABA. This effect was associated with improved plant water relations, increased cell membrane stability, reduced leaf abscission, and a transient reduction in plant growth rates.
Non Technical Summary |
| Gunasekera, R.., Sewgobind, K., Desai, S., Dunn, H., Black, H., McKeehan, W., and Patil, B., Lycopene and lutein inhibit proliferation in rat prostate carcinoma cells, Nutrition and Cancer, 2007, 58:117-121 |
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Consumption of lycopene, a carotenoid without provitamin A activity, has been associated with a lower risk of prostate and breast cancer. Lutein is another carotenoid that may be associated with a reduced risk of age-related macular degeneration, the leading cause of blindness in adults 65 years of age and older. Bioactive compounds such as lycopene and lutein, derived from natural plant sources, have been shown to act at low substrate levels through the action of intrinsic cytokines and growth factors and their receptors within tissues, particularly those of the fibroblast growth factor and transforming growth factor β families. The effects of grapefruit-derived and commercial lycopene and lutein preparations on androgen independent cultured malignant type II tumor cells [Dunning R3327AT3 or AT3 cells (androgen-responsive, slow-growing tumor cells with well developed epithelium and stroma)] were compared to their benign parent type I tumor epithelial cells (DTE). Results demonstrated that both lycopene, in an α-cyclodextrin water soluble carrier, and lutein inhibited malignant AT3 cells in a concentration and time-dependent manner. No such effect was observed when benign DTE cells were examined, demonstrating selective inhibition of extremely malignant AT3 prostate cancer cells relative to their benign parent. Lutein demonstrated a similar but slightly diminished response as lycopene. When cells were treated with cocktails of lycopene and lutein, no synergistic or additive effect occurred. These studies are consistent with epidemiological studies that show inverse relationships of these carotenoids with prostate cancer.
Non Technical Summary |
| Han, J., Oh, D., Chung, K., Kim, C., Park, S., Shigki, T., Hirschi, K., and Choi, C., Ectopic Expression of Arabidopsis CAX2 Variant Facilitates the Growth of Both Bottle Gourd and the Scion Grafted onto the Transgenic Rootstock, HortScience, 2007, 42(4):904-905, 2007 |
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Bottle gourd (Lagenaria siceraria Standl.) has been commonly used as a source of rootstock for watermelon. To improve its performance as a rootstock without adverse effects on the scion, the bottle gourd was genetically engineered using a chimeric Arabidopsis sCAX2B gene which encodes a variant transporter, N-terminus truncated form of CAX2 (sCAX2) containing the B domain of CAX1. The variant transporter was known to moderately enhance Ca2+ substrate specificity and to lose the excessive Mn2+ transport capability of sCAX2. Our results indicated that the transgenic bottle gourd expressing the sCAX2B was more vigorous than its wild type counterpart, and neither the transgenic bottle gourd seedlings showed any phenotypic abnormalities during the whole growth period. Several cucurbit crops were test-grafted onto the transgenic bottle gourd to determine its effect on the scions. The growth of both the transgenic bottle gourd and the grafted watermelon was faster than the control when estimated to be 35 days after greenhouse transplanting as evident from their growth indices like shoot length. Both grafting combinations also showed normal growth and development until fruit setting stage. Watermelon fruits with the watermelon/transgenic bottle gourd combination recorded higher osmotic pressure and more soluble solids than those with the wild type combination. The same procedure was also done for the oriental melon and melon which are incompatible with a bottle gourd. Such findings suggest that sCAX2B expression in the transformed bottle gourd rootstock can facilitate growth of the scion toward producing better quality fruits in terms of an accumulation of more photosynthetic products.
Non Technical Summary |
| Inan, G.,Goto, F., Jin, J., Bo, R., Abel, K., Hisashi, S., Huazhong, H., Gawa, P., Bressan, Ray A., Maggio, A., and Li, X., Isolation and characterization of shs1, a sugar-hypersensitive and ABA-insensitive mutant with multiple stress responses, Plant Mol. Biol, 2007, 65:295-309 |
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To identify salt tolerance determinants, we screened for double mutants from a T-DNA tagged SOS3-1 mutant population in the Arabidopsis Col-0 g11 background. The shs1-1 (sodium hypersensitive) sos3-1 mutant was isolated as more sensitive to NaCl than sos3-1 plants. TAIL-PCR revealed that the introduced T-DNA was located 62 hp upstream of the initiation codon of an adenylate translocator-like protein gene on chromosome IV. SHSI mRNA did not accumulate in shs1-1 sos3-1 plants although it accumulated in shoots of both sos3-1 and the wild type plants, indicating that this gene is inactive in the mutant. Genetic co-linkage analysis revealed that the mutation causing the phenotype segregated as a recessive, single gene mutation. This mutant showed altered sensitive responses to salt as well as to cold stress. It also demonstrated sugar sensitive and ABA insensitive phenotypes including enhanced germination, reduced growth, altered leaf morphology, and necrosis on leaves at an early growth stage. Sensivity of sos3-1 shs1-1 root growth to LiCl, KCl, and mannitol was not significantly different from growth of sos3-1 roots. Further, expression of 35S::SHS1 in sos3-1 shs1-1 plants complemented NaCl and sugar sensitivity and partially restored the leaf morphology.
Non Technical Summary |
| Jayaprakasha, G. and Patil, B., In vitro evaluation of the antioxidant activities in fruit extracts from citron and blood orange, 2007, Food Chemistry 101, 2007, 410-418 |
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Consumers are increasingly aware of diet related health problems and therefore demanding natural ingredients which are expected to be safe and health-promoting. Recently, number of studies on health benefits associated with citrus phytochemicals have been demonstrated. In the present study, an attempt has been made to isolate antioxidant fractions from two different citrus species such as Citron (Citrus medica) and blood orange (C. sinensis). Antioxidant fractions were extracted from mature, ripe fruits using five different solvents using a Soxhlet extractor. The total phenolic content of the extracts was determined by Folin–Ciocalteu method. MeOH:water (80:20) extract of citron and acetone extract of blood orange was found to contain maximum phenolics. The dried fractions were screened for their antioxidant activity potential using in vitro model systems such as 1, 1-diphenyl-2-picryl hydrazyl (DPPH), phosphomolybdenum method and as well as by the nitroblue tetrazolium (NBT) reduction test at different concentrations. The MeOH:water (80:20) fraction of citron showed highest radical scavenging activity 42.5%, 77.8% and 92.1% at 250, 500 and 1000 ppm, respectively, while MeOH:water (80:20) fraction of blood orange showed lowest DPPH radical scavenging activity at all the tested concentrations. Furthermore, all the fractions showed remarkable antioxidant capacity by the formation of phosphomolybdenum complex. In addition, superoxide radical scavenging activity was assayed using non-enzymatic (NADH/phenaxine methosulfate) superoxide generating system. All the extracts showed variable radical scavenging activity. The data obtained in the in vitro models clearly establish the antioxidant potency of citrus fruit extracts. However, comprehensive studies need to be conducted to ascertain the in vivo safety of such extracts in experimental animal models. To the best of our knowledge, this is the first report on antioxidant activity of citron and blood orange varieties of citrus fruits.
Non Technical Summary |
Jayaprakasha, G., Mandadi, K., Poulose, Shibu M., Jadegoud, Y., Gowda, G., and Patil, B., Inhibition of colon cancer cell growth and antioxidant activity of bioactive compounds from Poncirus trifoliate (L.) Raf., Bioorganic & Medicinal Chemistry, 2007, 15 4923-4932 |
Recently, several plants derived natural compounds have been screened for their anticancer activity in order to identify putative compounds with novel structures or mechanism of action. In the present study, fruits of Poncirus trifoliate were extracted with acetone and loaded onto silica gel column chromatography. The column was eluted with different solvents to obtain two bio-active compounds. The purity of compounds was analyzed by HPLC and their structures were identified by 1H and 23C NMR experiments as β-sitosterol and 2-hydroxy-1, 2, 3-propanetricarboxylic acid 2-methyl ester (HPCME). β-Sitosterol, HPCME, and toolbox were tested for their antioxidant capacity by oxygen radical absorbance capacity (ORAC) measurement. Further, these compounds were tested for their inhibition of cancer cell proliferation and apoptosis using human colon cancer cell line (HT-29). These results were compared with the corresponding activity on non-cancerous (COS-1 fibroblast) cells. Cell proliferation and induction of apoptosis determined by MTT assay and nuclear staining. The MTT assay indicated that both the compounds exhibited differential inhibition at various concentrations. Significant arrest of cell growth was observed with β-sitosterol even at low concentration such as 0.63 mM in 48 h and none of the compounds exerted any apparent cytostatic effects on the non-cancerous COS-1 fibroblast cells is the first report on HPCME isolation and identification from Rutaceae family and β-sitosterol from P. trifoliate.
Non Technical Summary |
Jayaprakasha, G., Negi, P., Jena, B., and Raio, L. , Antioxidant and antimutagenic activities of Cinnamomum zeylanicum fruit extracts, Journal of Food Composition and Analysis, 2007, 20 330-336 |
Recently, a number of studies on the health benefits associated with natural compounds have been demonstrated. Phenolics in fruits, vegetables, herbs and spices possess potent antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic activities. In the present study, the dried fruits of cinnamon were extracted with ethyl acetate, acetone, methanol and water using a Soxhler extractor. The total phenolics content of the extracts as determined by Folin-Ciocalteu method was found to be the highest in water extract (44.5%) and the lowest in ethyl acetate (14.4%). The antioxidant activity (AA) of the extracts was evaluated through in vitro model systems such as β-carotene-linoleate, and 1,1-diphenyl-2-picryl-hydrazyl (DPPH); the antimutagenicity of these extracts was also assayed against the mutagenicity of sodium azide by Ames test using tester strain of Salmonella typhimarium (TA100) at different concentrations. In both the sodium azide mutagenicity in S. typhimurium strain (TA100). At 500 mg/plate all the extracts showed strong antimutagenicity. The antimutagenicity of water extract was followed by acetone, methanol and ethyl acetate. The results of the present study indicate that under-utilized and unconventional part of cinnamon is a good source of antioxidant and antimutagenic henolics.
Non Technical Summary |
Kim, S., Yoo, K., and Pike, L., Production of doubled haploid onions (Allium cepa) and evaluation of their field performance. , 2007, Hort. Environ. Biotechnol. 48(3):143-147. |
Doubled haploid lines in onion (Allilum cepa) are homozygous for all loci and can be used as valuable materials for inheritance studies of complex traits and pure line production for F1 hybrids were produced and their field performance was compared with commercial open-pollinated cultivars. Six doubled haploid lines were produced from haploid culture. Four F1, hybrids were produced by crossing doubled haploid lines with sterile breeding lines. Doubled haploid lines, F1, hybrids, and five commercial open-pollinated cultivars were grown at two locations. After harvesting the bulbs, equatorial diameter, polar diameter, shape index, weight, soluble solid content, and pungency were measured. Doubled haploid lines and F1, hybrids generally showed higher uniformity as compared with commercial cultivars for all traits. Hybrid vigor, a good response lo favorable growing conditions and high stability were observed in F1, hybrids. Overall, it was demonstrated that doubled haploid lines were more uniform than open-pollinated cultivars and could be utilized as parental lines for F1, hybrid production with high uniformity.
Non Technical Summary |
Kim, S., Yoo, K., and Pike, L., Estimation Of Variance Of Red Color Intensity Of Onion Bulbs Utilizing A New Digital Imaging Quantification Method. , 2007, Hort. Environ. Biotechnol. 48:207-211. |
Bulb Color is an important trait in onion (Allium cepa) breeding, but the lack of a method to quantify and color intensity is a large number of samples have hindered assessment of essential breeding parameters such as heritability. We developed a new method on digital imagining that allows facile quantification of red color intensity in a large number of samples. The brightness of dry skin in digital images was measured using the histogram function of AdobeÒ PhotoshopÒand showed highly significant correlation with both visual rating of red haploid (DH) lines and location effects on red color development. Three red DH lines, four pink F, hybrids, and three red commercial cultivars were grown at two locations with three replications. DH lines showed less variation in combined analysis of variance from two locations.
Non Technical Summary |
Kim, S., Bang, H., Yoo, K., and Pike, L., Marker-assisted Genotype Analysis of Bulb Colors in Segregating Populations of Onions (Allium cepa), 2007, Molecules and Cells, Vol. 23, No. 2, pp. 192-197 |
Bulb color in onions (Allium cepa) is an important trait whose complex inheritance mechanism involves epistatic interactions among major color-related loci. Recent studies revealed that inactivation of dihydroflavonol4-reductase (DFR) in the anthocyanin synthesis pathway was responsible for the color differences between yellow and red onions, and two recessive alleles of the anthocyanidin synthase (ANS) gene were responsible for a pink bulb color, Based on mntatious in the recessive alleles of these two genes, PCRbased markers for allelic selection were developed. In this study, genotype analysis of onions from segregating populations was carried out using these PCR based markers. Segregating populations were derived from the cross between yellow and red onions. Five yellow and thirteen pink bulbs from one segregating breeding line were genotyped for the two genes. Four pink bulbs were heterozygous for the DFR gene, which explains the continuous segregation of yellow and pink colors in this line. Most pink onions were homozygous recessive for the ANS gene, except for two heterozygotes. This finding indicated that the homozygous recessive ANS gene was primarily responsible for the pink color in this line. The two pink onions, heterozygous for the ANS gene, were also heterozygous for the DFR gene, which indicated that the pink color was produced by incomplete dominance of a red color gene over that of yellow. One pink line and six other segregating breeding lines were also analyzed. The genotyping results matched perfectly with phenotypic color segregation.
Non Technical Summary |
| Korenkov, V., Hirschi, K., Crutchfield, J., and Wagner, G., Enhancing Tonoplast Cd/H Antiport activity Increases Cd, Zn, and Mn Tolerance and Impacts root/shoot Cd Partitioning in Nicotiana tabacum L., Planta, 2007, 226 (6):1379-1387. |
Sequestration mechanisms that prevent high concentrations of free metal ions from persisting im metabolically active compartments of cells are thought to be central in tolerance of plants to high levels of divalent cation metals. Expression of ArCAX2 or ArCAX4, which encode divalent cation/proton antiporters, in Nicotiana tabacum cv. KY14 results in enhanced Cd- and Zn-selective transport into root tonoplast vesicles, and enhanced Cd accumulation in roots of plants exposed to moderate, 0.02 mM Cd in solution culture (Korenkov et al. in Planta 225:403-411, 2007). Here we investigated effects of expressing ArCAX2 and ArCAX4 in the same lines on tolerance to growth with near-incipient toxicity levels of Cd, Zn and Mn. Less growth inhibition (higher tolerance) to all three metals was observed in 35S::ArCAX2 and FS3::ArCAX4 expressing plants. Consistent with the tolerance observed for Cd was the finding that while root tonoplast vesicle proton pump activities of control and FS3ArCAX4 expressing plants grown in 3 mM Cd were similarly reduced, and vesicle proton leak was enhanced, root tonoplast vesicle antiporter activity of these plants remained elevated above that in controls, We suggest that CAX antiporters, unlike tonoplast proton pump and membrane integrity, are not negatively impacted by high Cd, and that supplementation of tonoplast with AtCAX compensates somewhat for reduced tonoplast proton pump and proton leak, and thereby results in sufficient vacuolar Cd sequestration to provide higher tolerance. Results are consistent with the view that CAX2 and CAX4 antiporters of tonoplast play a role in tolerance to high, toxic levels of Cd, ZN and Mn in tobacco.
Non Technical Summary |
| Korenkov, V., Park, S., Cheng, N., Sreevidya, C., Lachmansingh, J., Morris, J., and Hirschi K., Enchanced Cd2+-selective root-tonoplast-transport in tobaccos expressing Arabidopsis cation exchangers., Planta, 2007, 225 (2):403-411. |
Several Arabidopsis Cation eXchangers (CAXs) encode tonoplast-localized transporters that appear to be major contributors to vacular accumulation/sequestration of cadmium (Cd2+), an undesirable pollutant ion that occurs in man largely as a result of dietary consumption of aerial tissues of food plants. But, ion-selectivity of individual CAX transporter types remains largely unknown. Here, we transformed Nicotiana tabacum with several CAX genes driven by the Cauliflower Mosaic Virus (CaMV) 35S promoter and monitored divalent cation transport in root-tonoplast vesicles from these plants in order to select particular CAX genes directing high Cd2+ antiporter activity in root tonoplast. Comparison of seven different CAX genes indicated that all transported Cd2+, Ca2+, Zn2+, and Mn2+ to varying degrees, but that CAX4 and CAX2 had high Cd2+transport and selectivity in tonoplast vesicles. CAX4 driven by the CaMV 35S and FS3 [figwort mosaic virus (FMV)] promoters increased the magnitude and initial rate of cd2+/H+ exchange in root-tonoplast vesicles. Ion selectivity of transport in root-tonoplast isolated from FS3::CAX4-expressing plant lines having a range of gene expression was Cd2+ > Zn2+ > Ca2+ > Mn2+ and the ratios of maimal Cd2+ (and Zn2+) versus maximal Ca2+ and Mn2+ transport were correlated with the levels of CAX4 expression. Root Cd accumulation in high CAX4 and CAX2 expressing lines was increased in seedlings grown with 0.02 mM Cd. These observations are consistent with a model in with expression of an Arabidopsis-gene-encoded, Cd2+-efficient antiporter in host plant roots results in greater root vacuole Cd2+ transport activity, increased root Cd accumulation, and a shift in overall root tonoplast ion transport selectivity towards high Cd2+ selectivity. Results support a model in which certain CAX antiporters are somewhat more selective for particular divalent cations.
Non Technical Summary |
| Leskovar, D., Bang, H., Kim, S., Yoo, S., King, S., and Crosby, K., Environmental And Genetic Factors On Carotenoids And Quality In Watermelon Fruits, Acta Horticulturae (ISHS), 2007, 744:233-241. |
Carotenoid compounds provide health benefits for humans such as antioxidant activity, prevention of cancer and heart diseases an enhancement of the immune system. They also contribute the red, orange and yellow color to fruits and flowers, harvest light and protect plants from photo-oxidation. Watermelon fruit is an excellent source of carotenoids, especially lycopene. Irrigation is essential for watermelon production and irrigation efficiency is becoming more critical in agricultural regions with highly regulated underground aquifers or with limited resources of surface water. We assessed environmental and genotypic effects on fruit quality and carotenoid content of diploid and triploid watermelon. Irrigation regimes were 1.0, 0.75 and 0.5 evapotranspiration (ET) imposed through subsurface drip in three distinctive geographical Texas locations. Lycopene content increased with maturity and was not decreased by deficit irrigation. Across environments, triploid cultivars appeared to be more stable in fruit quality characteristics and lycopene content than diploid cultivars. Both diploid and triploid red-fleshed cultivars had significantly higher total carotenoid content compared to orange- and yellow-fleshed cultivars. Integrating environmental, genetic and molecular studies aimed at the identification and quantification of the major carotenoids and the understanding of the regulatory mechanisms of carotenoid biosynthesis would facilitate breeding watermelons with enhanced level of these health-promoting compounds and with adaptability to a wider range of production regions.
Non Technical Summary |
Mandadi, K., Jayaprakasha, G., Bhat, N., and Patil, B., Red Mexican Grapefruit: A Novel Source For Bioactive Limonoids And Their Antioxidant Activity., Z. Naturforschung 62c, 2007, 179-188 |
Citrus limoids have shown to inhibit the growth of cancer in colon, lung, mouth, stomach and breast in animal and cell culture studies. For the first time in the present study, an attempt has been made to isolate antioxidant fractions and five limonoids from red Mexican grapefruit seeds. Defatted seed powder was successively extracted with hexane, ethyl acetate EtOAc), acetone, methanol (MeOH) and MeOH/water and the extracts were concentrated under vacuum. Radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and total phenolic content were also measured for comparison with the antioxidant capacity in the phosphomolybdenum method for the above extracts. Acetone and MeOH extracts, respectively, showed the highest (85.7%) and lowest (53.3%) radical scavenging activity, at 500 ppm. The total phenolic contents were found to be highest in the acetone extract (15.94%) followed by the MeOH extract (5.92%), ethyl acetate extract (5.54%) and water extract (5.26%). Antioxidant capacity of the extracts as equivalents to ascorbic acid (mmol/g of the extract) was in the order, Ei)Ac extract > acetone extract > water extract > methanol extract. Furthermore, the EtOAC and acetone extracts were loaded onto silica gel columns to obtain four limonoid aglycons, MeOH fraction was loaded onto a dower-x-50 and sepabeads resin column to obtain a limonolid glucoside. The purity of the isolated five compounds was analyzed by HPLC using a C18 column and UV detection at 210 nm. Finally, the structures of the compounds were identified as obacunone, nomillin, limonin, deacetylnomilin (DAN) and limonin-17-b-p-glucopyranoside (LG) using 1H and 13CNMR studies.
Non Technical Summary |
| Mei, H., Zhao, J., Pittman, J., Lachmansingh, J., Park, S., and Hirschi, K., In planta regulation of the Arabidopsis Ca2+/H+ antiporter CAX1., Journal of Experimental Botany, 2007, 58(12):3419-3427. |
Vacuolar localized Ca2+/H+ exchangers such as Arabidopsis thaliana cation exchanger 1 (CAX1) play important roles in Ca2+ homeostatasis. When expressed in yeast, CAX1 is regulated via an N-terminal autoinhibitory domain. In yeast expression assays, a 36 amino acid N-terminal turnction of CAX1, termed aCAX1, and variants with specific mutations in this N-terminus, show CAX1-mediated Ca2+/H+antiport activity. Furthermore, transgenic plants expressing sCAX1 display increased Ca2+ accumulation and heightened activity of vacuolar Ca2+/H+ antiport. Here the properties of N-terminal CAX1 variants in plants and yeast expression systems are compared and contrasted to determine if autoinhibition of CAS1 is occurring in planta. Initially, using ionome analysis, it has been demonstrated that only yeast cells expressing activated CAX1 transporters have altered total calcium content and fluctuations in zinc and nickel. Tobacco plants expressing activated CAX1 variants displayed hypersensitivity to ion imbalances, increased calcium accumulation, heightened concentrations of other mineral nutrients such as potassium, magnesium and manganese, and increased activity of tonoplast-enriched Ca2+/H+ transport. Despite high in planta gene expression, CAX1 and N-terminal variants of CAX1 which were not active in yeast, displayed none of the aforementioned phenotypes. Although several plant transporters appear to contain N-terminal auto-inhibitory domains, this work is the first to document clearly N-terminal-dependent regulation of a Ca2+ transporter in transgenic plants. Engineering the autoinhibityory domain thus provides a strategy to enhance transport function to affect agronomic traits.
Non Technical Summary |
| Morris J., Nakata, P., McConn, M., Brock, A., and Hirschi, K., Increased Calcium Bioavailability In Mice Fed Genetically Engineered Plants Lacking Calcium Oxalate., Plant Molecular Biology, 2007, 64(5):613-618. |
Bioavailable calcium affects bone formation and calcification. Here we investigate how a single gene mutation altering calcium partitioning in the model forage crop Medicago truncatula affects calcium bioavailability. Previously, the cod5 M. trunctula mutant was identified wich contains identical calcium concentrations to wild-type, but contains no oxalate crystals. In this study, equal number of male and female mice were randomly grouped and then fed one of four 45Ca-containing diets: M. truncatula extrinsic or intrinsically labeled and cod5 extrinsically or intrinsically labeled. Absorption of the tracer was determined in the legs one day after consumption. The absorption was similar in the M. truncatula and cod5 extrinsically labled diets; however, in the intrinsically labeled diets, calcium absorption was 22.87% (P < 0.001) higher in mice fed cod5. Our study presents the first genetic evidence demonstrating the nutritional impact of removing oxalate crystals from foods.
Non Technical Summary |
| Park, S., Sinclair, J., Crosby, K., Yoo, K., and Lester, G., Identification and Confirmation of RAPD Markers and Andromonoecious Associated with QTL for Sucrose in Muskmelon, Journal of American Society of Horticultural Sciences, 2007, 763:191-196 |
Our objectives were to identify RAPD and andromonoecioius (a) markers associated with QTL for sucrose using bulked segregant analysis in an F2 population from the melon (Cucumis melo L.) cross of 'TAM Dulce' (high sucrose) × TGR1551 (low sucrose) in a greenhouse experiment, and confirm the association of RAPD and a markers with sucrose QTL in an F2 population from the different cross of 'Deltex' (high sucrose) × TGR1551in a field experiment. Continuous distributions for sucrose were observed in the F2 populations indicating quantitative inheritance for the trait. A significant positive correlation was found between sucrose and total soluble solids (TSS). Nine RAPD markers were detected to be significantly associated with QTL for sucrose in the F2 population of the 'TAM Dulce' × TGR1551 cross in the greenhouse based on simple linear regression. Five unlinked markers associated with QTL were significant in a stepwise multiple regression analysis where the full model explained 39% of the total phenotypic variation for sucrose. Three to five of the nine RAPD markers were also observed to be significantly associated with QTL for glucose, controlled by the same QTL. Four RAPD markers were confirmed in the F2 population of the 'Deltex' × TGR1551 cross in the field to be consistently associated with sucrose QTL. A significant association of a with sucrose was consistently expressed in our populations under greenhouse and field environments.
Non Technical Summary |
| Poulose, S., Jayaprakasha, G., Meyer, R., Girennavar, B., and Patil, B., Purification of citrus limonoids and their differential inhibitory effects on human cytochrome P450 enzymes., 2007, J. Science Food and Agriculture 87:1699-1709 |
Recent studies demonstrated that citrus limonoids and flavonoids possess numerous health promoting properties. In the present study, glucosides of limonoids and flavonoids were purified from citrus molasses and Limonoid aglycones from citrus seeds. Glucosides were separated on styrene (divinylbenzene), Q-sepharose resins with increasing concentration of sodium chloride. A pH-dependent cold precipitation was carried out for the isolation of naringin in large quantity. Major aglycones such as limonin and nomilin were isolated from seeds by direct crystallization and minor limonoids were purified by vacuum liquid hromatography. The structures of the isolated compounds were confirmed by NMR spectra. Individual limonoids were tested for 0-dealkylase and hydroxylase activities of human cytochrome P450 (CYP) isoenzymes such as CYPlA2, CYPlB1, CYP3A4 and CYP19, using ethoxyresorufin, methoxyresorufin and dibenzylffuorescein as substrates. Partial to high inhibition of CYPs was observed in dose-dependent assays. Significant (P < 0.001) reductions in enzyme activities were observed with purified compounds above 2 pnol. Kinetic analyses indicated that limonin glucoside inhibited CYPl9 competitively (IC50, 7.1 m mol L-1), whereas Nomilinic acid glucoside inhibited it noncompetitively (IC50, 9.4~m ol-I). Nomilinic acid glucoside was the most potent limonoid, with an overall IC59.of < l0 m mol, for all the enzymes tested. The differential inhibition of CYPs can be ascribed to structural variations ofthe limonoid nucleus.Limonoid inhibition of key CYPs involved in carcinogenesis supports growing evidence that citrus limonoids act as anticancer agents.
Non Technical Summary |
Reyes, L. and Cisneros-Zevallos, L., Degradation kinetics and colour of anthocyanins in aqueous extracts of purple- and red-flesh potatoes (Solamun tuberosum L.), 2007, Food Chemistry 100: 885-894
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The effect of pH and temperature on the stability and visual colour of aqueous anthocyanin (ACY) extracts from purple- and red-flesh potatoes was evaluated and compared to commercial ACY extracts from grape and purple carrot. Extracts from purple carrot and redflesh potatoes showed higher stability than grape and purple-flesh potato extracts. Stability to pH (63) and thermal degradation of extracts (pH 3) followed first-order kinetics. Changes in lightness and hue followed zero-order kinetics, while changes in chroma followed first-order kinetics. Degradation parameters such as t1/2, k-, D-, z- and Q10-values were determined. Extracts from red- and purple-flesh.
Non Technical Summary |
Reyes, L., Villarreal, J., and Cisneros-Zevallos, L., The increase in antioxidant capacity after wounding depends on the type of fruit or vegetable tissue, Food Chemistry, 2007, 101 1254-1262 |
Wounding of fresh produce may elicit an increase in antioxidant capacity associated with wound-induced phenolic compounds. However, there have been no reports on the wounding response of different types of fresh produce. Changes in antioxidant capacity, total soluble phenolics, ascorbic acid, total carotenoids and total anthocyanins were evaluated after wounding in zucchini, white and red cabbage, iceberg lettuce, celery, carrot, parsnips, red radish, sweetpotato and potatoes. Phenolic changes ranged from a 26% decrease to an increase up to 191%, while antioxidant capacity changes ranged from a 51% decrease to an increase up to 442%. Reduced ascorbic acid decreased up to 82%, whereas the changes in anthocyanins and carotenoids were less evident. In general, the wound response was dependent on the type of tissue and influenced by the initial levels of reduced ascorbic acid and phenolic compounds. Wounding may increase the antioxidant content towards the development of selected healthier fresh-cut produce.
Non Technical Summary |
Tian, Q., Miller, E., Jayprakasha, G., and Patil, B., An improved HPLC method for the analysis of citrus limonoids in culture media, Journal of Chromagrphy B, 2007, 846:385-390 |
These results may suggest that hormone insensitive MDA MB 231 cell growth are not inhibited by limonin glucoside, limonin, obacunone and obacunone glucoside perhaps due to differential phosphorylations of serine residues of NFkB.
Non Technical Summary |
Vanamala, J., Cobb, G., Loiza, J., Yoo, K., Pike, L., and Patil, B., Ionizing Radiation and Marketing Simulation on Bioactive Compounds and Quality of Grapefruit (Citrus paradisi c.v. Rio Red)., Food Chemistry, 2007, 105:1404-1411. |
Bioactive compounds in citrus fruits have been shown to be protective against chronic diseases such as cancer and heart disease, but their levels may be affected by postharvest treatments such as storage and irradiation. In this study, grapefruits were exposed to gamma irradiation at 0, 150 and 300 Gy and then stored at 10 °C for 36 d, followed by an additional 20 d at 20 °C. Flavonoid content, terpenoid content, quality (acidity and total soluble solids) and phenylalanine ammonia-lyase (PAL) activity were evaluated at regular intervals during storage. Irradiation and storage affected (P £ 0.05) the levels of bioactive compounds in grapefruit; however, the effect of storage was prominent. Irradiation differentially affected the flavonoid content of pulp and peel. Fruits exposed to 300 Gy had higher (P £ 0.01) narirutin content in peel compared to control fruits at 12 and 56 d after storage. While storage increased the D-limonene and myrcene content in all treatments, control fruit had higher terpenoid content at the end of the storage. PAL activity was found to be in traces in the peel. In general, irradiation or storage had no considerable effect on total soluble solids; however, acidity decreased (P £ 0.05) with storage.
Non Technical Summary |
Vikram, A., Jayaprakasha, G., and Patil, B., Simultaneous determination of citrus limonoid aglycones and glucosides by high performance liquid chromatography, Analytica Chimica Acta, 2007, 290:180-186 |
High performance liquid chromatography (HPLC) method has been developed for simultaneous quantification of limonoid aglycones and glucoside on a reversed phase C18 column using a binary solvent system, coupled with diode array detector. Seven limonoids such as limonin, nomilin, isolimonic acid, ichangin, isoobacunoic acid, limonin 17- β-D glucopyranoside and deaetyl nomilinic acid 17- β-D glucopyranoside were separated and detected at 210 nm. Furthermore, limonoids were separated, identified and quantified in four varieties of citrus fruits and seeds using developed method. Limonoin and limonin glucoside were found to be the predominant limonoid aglycone and glucoside, respectively, in all tested samples. The sensitivity of the method was found to be 0.25-0.50 mg for tested limonoids.
Non Technical Summary |
| Villarreal, A., Stoecker, B., Garcia, C., Garcia, K., Rios, R., Gonzales, C, Mandadi, K., Faraji, B., Patil, B., and Deyhim, F., Cranberry Juice Improved Antioxidant Status Without Affecting Bone Quality In Orchidectomized Male Rats, Phytomedicine 14 (2007):815-820 |
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Background: We reported that drinking citrus juice improves bone quality in orchidectomized senescent male rats. Because cranberry juice, like citrus, is rich in nutrients and phenolic compounds, beneficial effects of citrus juice might also be seen with cranberry juice. An experiment evaluated effect of drinking cranberry juice on bone quality in orchidectomized rats. Methods: Thirty-two 1-year-old male rats were randomized to two groups: a sham-control group (n ¼ 8) and an orchidectomized group (n ¼ 24). The treatments for the 4 months duration of the study were SHAM, orchidectomy (ORX), ORX+drinking either 27% or 45% cranberry juice concentrate added to drinking water. At the termination of the study, the rats were euthanized, blood was collected for plasma antioxidant status and IGF-I. The femur, tibia and the 4th lumbar were evaluated for bone quality. Total calcium and magnesium concentration in the femurs were also evaluated. Results: ORX did not affect red blood cell (RBC)-induced hemolysis despite lowering (po0.05) plasma antioxidant capacity; reduced (po0.05) plasma IGF-I, femoral density, femoral strength, time-induced femoral fracture, bone mineral content, bone mineral area; numerically (p ¼ 0.07) lowered 4th lumbar density; decreased (po0.05) trabecular connectivity, trabecular number, femoral ash; increased (po0.05) trabecular separation in comparison to the SHAM group. Drinking cranberry juice increased (po0.05) plasma antioxidant status, protected RBC against hemolysis, but had no positive effect on bone quality or bone mineral status. Conclusions: Cranberry juice increases plasma antioxidant status without affecting bone quality.
Non Technical Summary |
| Villarreal-Lozoya, J., Lombardini, L., and Cisneros-Zevallos, L., Phytochemical constituents and antioxidant capacity of different pecan [Carya illinoinensis (Wangenh.) K. Koch] cultivars, Food Chmistry, 2007, 102 1241-1249 |
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Six pecan cultivars were analyzed for their antioxidant capacity (AC), total phenolics (TP), condensed tannin (CT), HPLC phenolic profile, tocopherol and fatty acid composition. Kernels which included the outer brown testa or pellicle, and shells which is the hard cover that surrounds the kernel, were evaluated for each cultivar. Strong correlations were found in kernels between AC and TP for both DPPH (r2 = 0.98) and ACORAC (r2 = 0.75) antioxidant assays. ACORAC values ranged from 372 to 817 μmol trolox equivalents/g defatted kernel, corresponding to Desirable and Kanza cultivars, respectively. CT ranged from 23 to 47 mg catechin equivalents/g defatted kernel and TP from 62 to 106 mg of chlorogenic acid equivalents/g defatted kernel. After a consecutive basic-acid hydrolysis, gallic acid, ellagic acid, catechin and epicatechin were identified by HPLC. The TP, AC and CT were 6, 4.5 and 18 times higher, respectively, for shells compared to kernels. The presence of phenolic compounds with high antioxidant capacity in kernels and shells indicates pecans can be considered an important dietary source of antioxidants.
Non Technical Summary |
| Vizzotto, M., Cisneros, L., Okie, W., Ramming, D., and Byrne, D., Large Variation Found In The Phytochemical Content And Antioxidant Activity Of Peach And Plum Germplasm., J. Amer. Soc. Hort. Sci., 2007, 132: 334-340 |
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Nineteen peach [Prunus persica (L.) Batsch] genotypes and 45 plum (Prunu salicina Erhr. And hybrids) gentoypes with different flesh and skin color were analyzed for their antioxidant content and activity. Anthocyanin content, phenolic content, and antioxidant activity were higher in red-flesh than in light-colored flesh peaches. Carotenoid content was higher in yellow-flesh peaches than in light-colored ones. Red-flesh plums generally had higher anthocyanin and phenolic contents than the other plums but not necessarily greather antioxidant capacity. The total phenolic content had the most consistent and highest correlation with antioxidant activity, indicating that it is more imporant in determining the antioxidant activity of peaches andplums than are the anthocyanin or carotenoid contents. In general, the wide range of phytochemical content and antioxidant activity found indicates that the genetic variability present can be used to develop cultivars with enhanced health benefits.
Non Technical Summary |
| Yu, J., Toledo, R., Singh, R., Dandekar, D., Pike, L., and Patil, B., Supercritical fluid extraction of Limonoids and Naringin from Grapefruit (Citrus Paradisi Macf.) seeds, Food Chemistry, 2007, 105:1026-1031 |
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Limonoids and naringin were extracted from grapefruit (Citrus paradisi Macf.) seeds by a supercriitical carbon dioxide (S-CO2) extraction technique. Prominent limonoids such as limonin and limonin-17-b-D-glucopyyranoside (LG) and flavonoid naringin were quantified for process optimization. Extraction was completed in two stages. In stage one less polar limonin was extracted using SC-CO2 while in stage two extraction of high polar LG and naringin were completed using SC-Co2 modified by ethanol as co-solvent. Extraction parameters were studied using Box-Behnken experiment design. Response surface analysis (RSA) of the data was completed to determine effects of variables on extraction efficiency. Highest yield of limonin (6.3 mg/g seeds) was achieved at 48.3 MPa pressure, 50 °C temperature and 60 min of extraction time where as highest yield of LG (0.62 mg/g seeds) was achieved at 41.4 MPa pressure, 60 °C temperature and 20% ethanol concentration in 40 min. Highest yield of naringin (0.2 mg/g seeds) was achieved at 41.4MPa pressure, 50 °C temperature and 20% ethanol concentration in 40 min. In all the experiments, mobile phase flow rate was kept constant at 5.0 L/min. The results demonstrated environmentally friendly, practical application of supercritical CO2 extraction of limonoids and flavonoids from grapefruit seeds.
Non Technical Summary |
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