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Muneharu Esaka - One of the best experts on this subject based on the ideXlab platform.
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overexpression of the Acerola malpighia glabra monodehydroascorbate reductase gene in transgenic tobacco plants results in increased ascorbate levels and enhanced tolerance to salt stress
South African Journal of Botany, 2012Co-Authors: Hani A Elteliba, Yukichi Fujikawa, Muneharu EsakaAbstract:Abstract Monodehydroascorbate reductase (MDHAR, EC 1.6.5.4) is a key enzyme of the ascorbate (AsA)-glutathione cycle that maintains reduced pools of AsA and serves as an important antioxidative enzyme. Previously, we have cloned MDHAR cDNA from Acerola (Malpighia glabra), a plant that accumulates abundant amount of AsA. In this study, MDHAR cDNA from Acerola was introduced into tobacco plants using an Agrobacterium-mediated gene delivery system. Transgenic tobacco plants accumulated greater amounts of AsA and showed higher MDHAR activity than the control plants. Lipid peroxidation and chlorophyll degradation, which were stimulated in control plants, were restrained in transgenic plants subjected to salt stress. These results indicate that overexpression of Acerola MDHAR imparts greater tolerance to salt stress.
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Gene expression of monodehydroascorbate reductase and dehydroascorbate reductase during fruit ripening and in response to environmental stresses in Acerola (Malpighia glabra)
Journal of plant physiology, 2010Co-Authors: Hani A. Eltelib, Adebanjo A. Badejo, Yukichi Fujikawa, Muneharu EsakaAbstract:Acerola (Malpighia glabra) is an exotic fruit cultivated primarily for its abundant ascorbic acid (AsA) content. The molecular mechanisms that regulate the metabolism of AsA in Acerola have yet to be defined. Monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR) are key enzymes of the ascorbate-glutathione cycle that maintain reduced pools of ascorbic acid and serve as important antioxidants. cDNAs encoding MDHAR and DHAR were isolated from Acerola using RT-PCR and RACE. Phylogenetic trees associated Acerola MDHAR and DHAR with other plant cytosolic MDHARs and DHARs. Expressions of the two genes correlated with their enzymatic activities and were differentially regulated during fruit ripening. Interestingly, MDHAR expression was only detected in overripe fruits, whereas the transcript level of DHAR was highest at the intermediate stage of fruit ripening. Under dark conditions, there was a sharp and significant decline in the total and reduced ascorbate contents, accompanied by a decrease in the level of transcripts and enzyme activities of the two genes in Acerola leaves. MDHAR and DHAR transcripts and enzyme activities were significantly up-regulated in the leaves of Acerola under cold and salt stress conditions, indicating that expression of both genes are transcriptionally regulated under these stresses.
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Increase in Ascorbate Content of Transgenic Tobacco Plants Overexpressing the Acerola (Malpighia glabra) Phosphomannomutase Gene
Plant & cell physiology, 2009Co-Authors: Adebanjo A. Badejo, Hani A. Eltelib, Yukichi Fujikawa, Kazunari Fukunaga, Muneharu EsakaAbstract:Phosphomannomutase (PMM; EC 5.4.2.8) catalyzes the interconversion of mannose-6-phosphate to mannose-1-phosphate in the Smirnoff-Wheeler pathway for the biosynthesis of l-ascorbic acid (AsA). We have cloned the PMM cDNA from Acerola (Malpighia glabra), a plant containing an enormous amount of AsA. The AsA contents correlate with the PMM gene expression of the ripening fruits and leaves. The PMM activities in the leaves of Acerola, tomato and Arabidopsis correlate with their respective AsA contents. Transgenic tobacco plants overexpressing the Acerola PMM gene showed about a 2-fold increase in AsA contents compared with the wild type, with a corresponding correlation with the PMM transcript levels and activities.
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Analysis of GDP-D-Mannose Pyrophosphorylase Gene Promoter from Acerola (Malpighia glabra) and Increase in Ascorbate Content of Transgenic Tobacco Expressing the Acerola Gene
Plant & cell physiology, 2007Co-Authors: Adebanjo A. Badejo, Nobukazu Tanaka, Muneharu EsakaAbstract:GDP-D-mannose pyrophosphorylase (GMP) is an important enzyme in the Smirnoff-Wheeler's pathway for the biosynthesis of ascorbic acid (AsA) in plants. We have reported recently that the expression of the Acerola (Malpighia glabra) GMP gene, designated MgGMP, correlates with the AsA content of the plant. The Acerola plant has very high levels of AsA relative to better studied model plants such as Arabidopsis. Here we found that the GMP mRNA levels in Acerola are higher than those from Arabidopsis and tomato. Also, the transient expression of the uidA reporter gene in the protoplasts of Nicotiana tabacum cultures showed the MgGMP gene promoter to have higher activity than the cauliflower mosaic virus 35S and Arabidopsis GMP promoters. The AsA content of transgenic tobacco plants expressing the MgGMP gene including its promoter was about 2-fold higher than that of the wild type.
Sebastien Dupont - One of the best experts on this subject based on the ideXlab platform.
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Comparison of the antioxidant property of Acerola extracts with synthetic antioxidants using an in vivo method with yeasts
Food Chemistry, 2019Co-Authors: Richtier Gonçalves Da Cruz, Simone Possedente De Lira, Thais Maria Ferreira De Souza Vieira, Patrick Gervais, Laurent Beney, Sebastien DupontAbstract:In this study, we compared the antioxidant activity of ripe and unripe Acerola extracts with synthetic antioxidants (BHA and BHT). This activity was assessed by classical approaches (DPPH and ABTS) and by an in vivo method using yeasts. Acerola extracts contain phenolic compounds and ascorbic acid that exhibit radical scavenger capacity and reducing power. The results obtained with yeasts revealed that the Acerola extracts and BHT either acted as antioxidants or presented no activity depending on the nature of the oxidant molecule used. BHA decreased yeast resistance to oxidative treatments and also showed deleterious effects even when oxidative treatments were not applied. The unripe Acerola was the most efficient antioxidant in the in vitro experiments but not necessarily in the in vivo assays, showing the weakness of in vitro systems in predicting antioxidant responses for biological purposes. BHA presented cell damaging effects even in the absence of oxidizing reagents.
Elisângela Gomes Fidelis Morais - One of the best experts on this subject based on the ideXlab platform.
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First record of Acerola weevil, Anthonomus tomentosus (Faust, 1894) (Coleoptera: Curculionidae), in Brazil.
Brazilian Journal of Biology, 2017Co-Authors: A. L. Marsaro Júnior, Paulo Roberto Valle Da Silva Pereira, Germano Henrique Rosado-neto, Elisângela Gomes Fidelis MoraisAbstract:Abstract The weevil of Acerola fruits, Anthonomus tomentosus (Faust, 1894) (Coleoptera: Curculionidae), is recorded for the first time in Brazil. Samples of this insect were collected in fruits of Acerola, Malpighia emarginata D.C. (Malpighiaceae), in four municipalities in the north-central region of Roraima State, in the Brazilian Amazon. Information about injuries observed in fruits infested with A. tomentosus , its distribution in Roraima, and suggestions for pest management are presented. Keywords: Brazilian Amazon, quarantine pests, fruticulture, geographical distribution, host plants. Primeiro registro do bicudo dos frutos da Acerola, Anthonomus tomentosus (Faust, 1894) (Coleoptera: Curculionidae), no Brasil Resumo O bicudo dos frutos da Acerola, Anthonomus tomentosus (Faust, 1894) (Coleoptera: Curculionidae), e registrado pela primeira vez no Brasil. Amostras deste inseto foram coletadas em frutos de Acerola, Malpighia emarginata D.C. (Malpighiaceae), em quatro municipios do Centro-Norte do Estado de Roraima, na Amazonia brasileira. Informacoes sobre as injurias observadas nos frutos infestados por
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First record of Acerola weevil, Anthonomus tomentosus (Faust, 1894) (Coleoptera: Curculionidae), in Brazil.
Brazilian journal of biology = Revista brasleira de biologia, 2017Co-Authors: A. L. Marsaro Júnior, Paulo Roberto Valle Da Silva Pereira, Germano Henrique Rosado-neto, Elisângela Gomes Fidelis MoraisAbstract:The weevil of Acerola fruits, Anthonomus tomentosus (Faust, 1894) (Coleoptera: Curculionidae), is recorded for the first time in Brazil. Samples of this insect were collected in fruits of Acerola, Malpighia emarginata D.C. (Malpighiaceae), in four municipalities in the north-central region of Roraima State, in the Brazilian Amazon. Information about injuries observed in fruits infested with A. tomentosus, its distribution in Roraima, and suggestions for pest management are presented.
Richtier Gonçalves Da Cruz - One of the best experts on this subject based on the ideXlab platform.
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Comparison of the antioxidant property of Acerola extracts with synthetic antioxidants using an in vivo method with yeasts
Food Chemistry, 2019Co-Authors: Richtier Gonçalves Da Cruz, Simone Possedente De Lira, Thais Maria Ferreira De Souza Vieira, Patrick Gervais, Laurent Beney, Sebastien DupontAbstract:In this study, we compared the antioxidant activity of ripe and unripe Acerola extracts with synthetic antioxidants (BHA and BHT). This activity was assessed by classical approaches (DPPH and ABTS) and by an in vivo method using yeasts. Acerola extracts contain phenolic compounds and ascorbic acid that exhibit radical scavenger capacity and reducing power. The results obtained with yeasts revealed that the Acerola extracts and BHT either acted as antioxidants or presented no activity depending on the nature of the oxidant molecule used. BHA decreased yeast resistance to oxidative treatments and also showed deleterious effects even when oxidative treatments were not applied. The unripe Acerola was the most efficient antioxidant in the in vitro experiments but not necessarily in the in vivo assays, showing the weakness of in vitro systems in predicting antioxidant responses for biological purposes. BHA presented cell damaging effects even in the absence of oxidizing reagents.
Adebanjo A. Badejo - One of the best experts on this subject based on the ideXlab platform.
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Gene expression of monodehydroascorbate reductase and dehydroascorbate reductase during fruit ripening and in response to environmental stresses in Acerola (Malpighia glabra)
Journal of plant physiology, 2010Co-Authors: Hani A. Eltelib, Adebanjo A. Badejo, Yukichi Fujikawa, Muneharu EsakaAbstract:Acerola (Malpighia glabra) is an exotic fruit cultivated primarily for its abundant ascorbic acid (AsA) content. The molecular mechanisms that regulate the metabolism of AsA in Acerola have yet to be defined. Monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR) are key enzymes of the ascorbate-glutathione cycle that maintain reduced pools of ascorbic acid and serve as important antioxidants. cDNAs encoding MDHAR and DHAR were isolated from Acerola using RT-PCR and RACE. Phylogenetic trees associated Acerola MDHAR and DHAR with other plant cytosolic MDHARs and DHARs. Expressions of the two genes correlated with their enzymatic activities and were differentially regulated during fruit ripening. Interestingly, MDHAR expression was only detected in overripe fruits, whereas the transcript level of DHAR was highest at the intermediate stage of fruit ripening. Under dark conditions, there was a sharp and significant decline in the total and reduced ascorbate contents, accompanied by a decrease in the level of transcripts and enzyme activities of the two genes in Acerola leaves. MDHAR and DHAR transcripts and enzyme activities were significantly up-regulated in the leaves of Acerola under cold and salt stress conditions, indicating that expression of both genes are transcriptionally regulated under these stresses.
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Increase in Ascorbate Content of Transgenic Tobacco Plants Overexpressing the Acerola (Malpighia glabra) Phosphomannomutase Gene
Plant & cell physiology, 2009Co-Authors: Adebanjo A. Badejo, Hani A. Eltelib, Yukichi Fujikawa, Kazunari Fukunaga, Muneharu EsakaAbstract:Phosphomannomutase (PMM; EC 5.4.2.8) catalyzes the interconversion of mannose-6-phosphate to mannose-1-phosphate in the Smirnoff-Wheeler pathway for the biosynthesis of l-ascorbic acid (AsA). We have cloned the PMM cDNA from Acerola (Malpighia glabra), a plant containing an enormous amount of AsA. The AsA contents correlate with the PMM gene expression of the ripening fruits and leaves. The PMM activities in the leaves of Acerola, tomato and Arabidopsis correlate with their respective AsA contents. Transgenic tobacco plants overexpressing the Acerola PMM gene showed about a 2-fold increase in AsA contents compared with the wild type, with a corresponding correlation with the PMM transcript levels and activities.
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Analysis of GDP-D-Mannose Pyrophosphorylase Gene Promoter from Acerola (Malpighia glabra) and Increase in Ascorbate Content of Transgenic Tobacco Expressing the Acerola Gene
Plant & cell physiology, 2007Co-Authors: Adebanjo A. Badejo, Nobukazu Tanaka, Muneharu EsakaAbstract:GDP-D-mannose pyrophosphorylase (GMP) is an important enzyme in the Smirnoff-Wheeler's pathway for the biosynthesis of ascorbic acid (AsA) in plants. We have reported recently that the expression of the Acerola (Malpighia glabra) GMP gene, designated MgGMP, correlates with the AsA content of the plant. The Acerola plant has very high levels of AsA relative to better studied model plants such as Arabidopsis. Here we found that the GMP mRNA levels in Acerola are higher than those from Arabidopsis and tomato. Also, the transient expression of the uidA reporter gene in the protoplasts of Nicotiana tabacum cultures showed the MgGMP gene promoter to have higher activity than the cauliflower mosaic virus 35S and Arabidopsis GMP promoters. The AsA content of transgenic tobacco plants expressing the MgGMP gene including its promoter was about 2-fold higher than that of the wild type.
