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Andrew C Allan - One of the best experts on this subject based on the ideXlab platform.
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transcriptional regulation of flavonoid biosynthesis in nectarine Prunus persica by a set of r2r3 myb transcription factors
BMC Plant Biology, 2013Co-Authors: Daniela Ravaglia, Richard V Espley, Rebecca A Henrykirk, Carlo Andreotti, Vanina Ziosi, Roger P Hellens, Guglielmo Costa, Andrew C AllanAbstract:Flavonoids such as anthocyanins, flavonols and proanthocyanidins, play a central role in fruit colour, flavour and health attributes. In peach and nectarine (Prunus persica) these compounds vary during fruit growth and ripening. Flavonoids are produced by a well studied pathway which is transcriptionally regulated by members of the MYB and bHLH transcription factor families. We have isolated nectarine flavonoid regulating genes and examined their expression patterns, which suggests a critical role in the regulation of flavonoid biosynthesis. In nectarine, expression of the genes encoding enzymes of the flavonoid pathway correlated with the concentration of proanthocyanidins, which strongly increases at mid-development. In contrast, the only gene which showed a similar pattern to anthocyanin concentration was UDP-glucose-flavonoid-3-O-glucosyltransferase (UFGT), which was high at the beginning and end of fruit growth, remaining low during the other developmental stages. Expression of flavonol synthase (FLS1) correlated with flavonol levels, both temporally and in a tissue specific manner. The pattern of UFGT gene expression may be explained by the involvement of different transcription factors, which up-regulate flavonoid biosynthesis (MYB10, MYB123, and bHLH3), or repress (MYB111 and MYB16) the transcription of the biosynthetic genes. The expression of a potential proanthocyanidin-regulating transcription factor, MYBPA1, corresponded with proanthocyanidin levels. Functional assays of these transcription factors were used to test the specificity for flavonoid regulation. MYB10 positively regulates the promoters of UFGT and dihydroflavonol 4-reductase (DFR) but not leucoanthocyanidin reductase (LAR). In contrast, MYBPA1 trans-activates the promoters of DFR and LAR, but not UFGT. This suggests exclusive roles of anthocyanin regulation by MYB10 and proanthocyanidin regulation by MYBPA1. Further, these transcription factors appeared to be responsive to both developmental and environmental stimuli.
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transcriptional regulation of flavonoid biosynthesis in nectarine Prunus persica by a set of r2r3 myb transcription factors
Science & Engineering Faculty, 2013Co-Authors: Daniela Ravaglia, Richard V Espley, Rebecca A Henrykirk, Carlo Andreotti, Vanina Ziosi, Roger P Hellens, Guglielmo Costa, Andrew C AllanAbstract:Background Flavonoids such as anthocyanins, flavonols and proanthocyanidins, play a central role in fruit colour, flavour and health attributes. In peach and nectarine (Prunus persica) these compounds vary during fruit growth and ripening. Flavonoids are produced by a well studied pathway which is transcriptionally regulated by members of the MYB and bHLH transcription factor families. We have isolated nectarine flavonoid regulating genes and examined their expression patterns, which suggests a critical role in the regulation of flavonoid biosynthesis. Results In nectarine, expression of the genes encoding enzymes of the flavonoid pathway correlated with the concentration of proanthocyanidins, which strongly increases at mid-development. In contrast, the only gene which showed a similar pattern to anthocyanin concentration was UDP-glucose-flavonoid-3-O-glucosyltransferase (UFGT), which was high at the beginning and end of fruit growth, remaining low during the other developmental stages. Expression of flavonol synthase (FLS1) correlated with flavonol levels, both temporally and in a tissue specific manner. The pattern of UFGT gene expression may be explained by the involvement of different transcription factors, which up-regulate flavonoid biosynthesis (MYB10, MYB123, and bHLH3), or repress (MYB111 and MYB16) the transcription of the biosynthetic genes. The expression of a potential proanthocyanidin-regulating transcription factor, MYBPA1, corresponded with proanthocyanidin levels. Functional assays of these transcription factors were used to test the specificity for flavonoid regulation. Conclusions MYB10 positively regulates the promoters of UFGT and dihydroflavonol 4-reductase (DFR) but not leucoanthocyanidin reductase (LAR). In contrast, MYBPA1 trans-activates the promoters of DFR and LAR, but not UFGT. This suggests exclusive roles of anthocyanin regulation by MYB10 and proanthocyanidin regulation by MYBPA1. Further, these transcription factors appeared to be responsive to both developmental and environmental stimuli.
Marina Carbonaro - One of the best experts on this subject based on the ideXlab platform.
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modulation of antioxidant compounds in organic vs conventional fruit peach Prunus persica l and pear pyrus communis l
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Marina Carbonaro, Maria Mattera, Stefano Nicoli, Paolo Bergamo, M CappelloniAbstract:Despite the increasing interest in organic products, knowledge about how different levels of fertilization affect nutritionally relevant components is still limited. The concentration of polyphenols and the activity of polyphenoloxidase (PPO), together with the content in ascorbic acid, citric acid, and α- and γ-tocopherol, were assayed in conventional and organic peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams). 2-Thiobarbituric acid reactive substances and the tocopherolquinone/α-tocopherol ratio were used as markers of oxidative damage in fruits. A parallel increase in polyphenol content and PPO activity of organic peach and pear as compared with the corresponding conventional samples was found. Ascorbic and citric acids were higher in organic than conventional peaches, whereas α-tocopherol was increased in organic pear. The concentration of oxidation products in organic samples of both fruits was comparable to that of the corresponding conventional ones. These da...
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modulation of antioxidant compounds in organic vs conventional fruit peach Prunus persica l and pear pyrus communis l
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Marina Carbonaro, Maria Mattera, Stefano Nicoli, Paolo Bergamo, M CappelloniAbstract:Despite the increasing interest in organic products, knowledge about how different levels of fertilization affect nutritionally relevant components is still limited. The concentration of polyphenols and the activity of polyphenoloxidase (PPO), together with the content in ascorbic acid, citric acid, and alpha- and gamma-tocopherol, were assayed in conventional and organic peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams). 2-Thiobarbituric acid reactive substances and the tocopherolquinone/alpha-tocopherol ratio were used as markers of oxidative damage in fruits. A parallel increase in polyphenol content and PPO activity of organic peach and pear as compared with the corresponding conventional samples was found. Ascorbic and citric acids were higher in organic than conventional peaches, whereas alpha-tocopherol was increased in organic pear. The concentration of oxidation products in organic samples of both fruits was comparable to that of the corresponding conventional ones. These data provide evidence that an improvement in the antioxidant defense system of the plant occurred as a consequence of the organic cultivation practice. This is likely to exert protection against damage of fruit when grown in the absence of pesticides.
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Polyphenoloxidase activity and polyphenol levels in organically and conventionally grown peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams)
Food Chemistry, 2001Co-Authors: Marina Carbonaro, Maria MatteraAbstract:Abstract Polyphenoloxidase (PPO) activity and total polyphenol content were tested in organically and conventionally grown whole fruits, peach ( Prunus persica L., cv. Regina bianca) and pear ( Pyrus communis L., cv. Williams), in order to evaluate the existence of a relationship between these parameters and of differences between fruits obtained with the two cultivation practices. Organic fruits were obtained on three different grounds: subterranean clover (sample A), spontaneous weed cover (sample B) and tilled (sample C). From the latter soil, the conventionally grown fruits were produced. All organic peach samples showed a highly significant ( P P
Maria Mattera - One of the best experts on this subject based on the ideXlab platform.
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modulation of antioxidant compounds in organic vs conventional fruit peach Prunus persica l and pear pyrus communis l
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Marina Carbonaro, Maria Mattera, Stefano Nicoli, Paolo Bergamo, M CappelloniAbstract:Despite the increasing interest in organic products, knowledge about how different levels of fertilization affect nutritionally relevant components is still limited. The concentration of polyphenols and the activity of polyphenoloxidase (PPO), together with the content in ascorbic acid, citric acid, and α- and γ-tocopherol, were assayed in conventional and organic peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams). 2-Thiobarbituric acid reactive substances and the tocopherolquinone/α-tocopherol ratio were used as markers of oxidative damage in fruits. A parallel increase in polyphenol content and PPO activity of organic peach and pear as compared with the corresponding conventional samples was found. Ascorbic and citric acids were higher in organic than conventional peaches, whereas α-tocopherol was increased in organic pear. The concentration of oxidation products in organic samples of both fruits was comparable to that of the corresponding conventional ones. These da...
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modulation of antioxidant compounds in organic vs conventional fruit peach Prunus persica l and pear pyrus communis l
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Marina Carbonaro, Maria Mattera, Stefano Nicoli, Paolo Bergamo, M CappelloniAbstract:Despite the increasing interest in organic products, knowledge about how different levels of fertilization affect nutritionally relevant components is still limited. The concentration of polyphenols and the activity of polyphenoloxidase (PPO), together with the content in ascorbic acid, citric acid, and alpha- and gamma-tocopherol, were assayed in conventional and organic peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams). 2-Thiobarbituric acid reactive substances and the tocopherolquinone/alpha-tocopherol ratio were used as markers of oxidative damage in fruits. A parallel increase in polyphenol content and PPO activity of organic peach and pear as compared with the corresponding conventional samples was found. Ascorbic and citric acids were higher in organic than conventional peaches, whereas alpha-tocopherol was increased in organic pear. The concentration of oxidation products in organic samples of both fruits was comparable to that of the corresponding conventional ones. These data provide evidence that an improvement in the antioxidant defense system of the plant occurred as a consequence of the organic cultivation practice. This is likely to exert protection against damage of fruit when grown in the absence of pesticides.
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Polyphenoloxidase activity and polyphenol levels in organically and conventionally grown peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams)
Food Chemistry, 2001Co-Authors: Marina Carbonaro, Maria MatteraAbstract:Abstract Polyphenoloxidase (PPO) activity and total polyphenol content were tested in organically and conventionally grown whole fruits, peach ( Prunus persica L., cv. Regina bianca) and pear ( Pyrus communis L., cv. Williams), in order to evaluate the existence of a relationship between these parameters and of differences between fruits obtained with the two cultivation practices. Organic fruits were obtained on three different grounds: subterranean clover (sample A), spontaneous weed cover (sample B) and tilled (sample C). From the latter soil, the conventionally grown fruits were produced. All organic peach samples showed a highly significant ( P P
M Cappelloni - One of the best experts on this subject based on the ideXlab platform.
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modulation of antioxidant compounds in organic vs conventional fruit peach Prunus persica l and pear pyrus communis l
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Marina Carbonaro, Maria Mattera, Stefano Nicoli, Paolo Bergamo, M CappelloniAbstract:Despite the increasing interest in organic products, knowledge about how different levels of fertilization affect nutritionally relevant components is still limited. The concentration of polyphenols and the activity of polyphenoloxidase (PPO), together with the content in ascorbic acid, citric acid, and α- and γ-tocopherol, were assayed in conventional and organic peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams). 2-Thiobarbituric acid reactive substances and the tocopherolquinone/α-tocopherol ratio were used as markers of oxidative damage in fruits. A parallel increase in polyphenol content and PPO activity of organic peach and pear as compared with the corresponding conventional samples was found. Ascorbic and citric acids were higher in organic than conventional peaches, whereas α-tocopherol was increased in organic pear. The concentration of oxidation products in organic samples of both fruits was comparable to that of the corresponding conventional ones. These da...
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modulation of antioxidant compounds in organic vs conventional fruit peach Prunus persica l and pear pyrus communis l
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Marina Carbonaro, Maria Mattera, Stefano Nicoli, Paolo Bergamo, M CappelloniAbstract:Despite the increasing interest in organic products, knowledge about how different levels of fertilization affect nutritionally relevant components is still limited. The concentration of polyphenols and the activity of polyphenoloxidase (PPO), together with the content in ascorbic acid, citric acid, and alpha- and gamma-tocopherol, were assayed in conventional and organic peach (Prunus persica L., cv. Regina bianca) and pear (Pyrus communis L., cv. Williams). 2-Thiobarbituric acid reactive substances and the tocopherolquinone/alpha-tocopherol ratio were used as markers of oxidative damage in fruits. A parallel increase in polyphenol content and PPO activity of organic peach and pear as compared with the corresponding conventional samples was found. Ascorbic and citric acids were higher in organic than conventional peaches, whereas alpha-tocopherol was increased in organic pear. The concentration of oxidation products in organic samples of both fruits was comparable to that of the corresponding conventional ones. These data provide evidence that an improvement in the antioxidant defense system of the plant occurred as a consequence of the organic cultivation practice. This is likely to exert protection against damage of fruit when grown in the absence of pesticides.
Hawari, Fathan Luthfi - One of the best experts on this subject based on the ideXlab platform.
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Aktivitas antibakteri fraksi buah jambu Wer (Prunus persica (L.) Batsch) terhadap pertumbuhan bakteri Shigella Dysenteriae
2019Co-Authors: Hawari, Fathan LuthfiAbstract:INDONESIA: Secara turun temurun masyarakat suku Tengger telah memanfaatkan buah jambu wer (Prunus persica (L.) Batsch) sebagai obat tradisional untuk diare dan sariawan. Penelitian ini bertujuan untuk mengetahui aktivitas antibakteri fraksi buah jambu wer terhadap pertumbuhan bakteri Shigella dysenteriae dan untuk mengetahui fraksi manakah yang memiliki aktivitas antibakteri tertinggi. Fraksi didapatkan dari ekstrak etanol 96% buah jambu wer (Prunus persica (L.) Batsch) menggunakan metode ekstraksi cair-cair. Fraksi yang diperoleh diuji aktivitas antibakterinya dengan metode difusi sumuran dan menggunakan Mueller-Hinton Agar (MHA) sebagai media tumbuh bakteri. Hasil yang didapatkan menunjukkan adanya zona hambat pada masing-masing fraksi dengan dosis 3% yaitu fraksi n-heksana sebesar 4,48 mm; fraksi kloroform 3,98 mm; fraksi etil asetat 6,51 mm dan fraksi air 0,98 mm. Dari hasil uji statistik One-Way ANOVA dengan taraf signifikan α=0,05 dapat disimpulkan bahwa fraksi buah Jambu Wer (Prunus persica (L.) Batsch) dengan pelarut etil asetat, kloroform, n-heksan dan air mempunyai aktivitas antibakteri yang secara statistik berbeda terhadap pertumbuhan bakteri Shigella dysenteriae. Dari hasil penelitian juga didapatkan bahwa fraksi buah jambu wer (Prunus persica (L.) Batsch) dengan pelarut etil asetat merupakan fraksi yang memiliki aktivitas antibakteri tertinggi terhadap pertumbuhan bakteri Shigella dysenteriae yaitu sebesar 6,51 mm. ENGLISH: From generation to generation, people of Tengger has used the jambu wer (Prunus persica (L.) Batsch) as traditional medicine for diarrheal and thrush disease. This research aims to know the antibacterial activity of jambu wer fruit fraction against the growth of bacteria Shigella dysenteriae and to know which fraction has the highest antibacterial activity. The fraction obtained from 96% ethanol extract of jambu wer (Prunus persica (L.) Batsch) by using a liquid-liquid extraction method. The obtained fraction was tested for antibacterial activity by the method of well diffusion and using Mueller-Hinton Agar (MHA) as the bacteria grow media. The results showed there is an inhibition zone in each fraction with a dose of 3%, namely n-hexane fraction of 4.48 mm; chloroform fraction 3.98 mm; ethyl acetate fraction 6.51 mm and water fraction 0.98 mm. From the One-Way ANOVA statistical test with a significant level of α = 0.05, it can be concluded that the fraction of jambu wer (Prunus persica (L.) Batsch) Fruit with the solvent ethyl acetate, chloroform, n-hexane and water has antibacterial activity that is statistically different from the growth of bacteria Shigella dysenteriae. From the results of the study it was also found that the fraction of jambu wer (Prunus persica (L.) Batsch) Fruit with ethyl acetate solvent was the fraction that had the highest antibacterial activity against the growth of Shigella dysenteriae bacteria which was 6.51 mm
