RESUMEN
Glycine betaine (GB) treatment is useful to reduce chilling injury (CI) of several kinds of fruits including peach. However, the regulatory mechanism remains unknown. In this study, peach fruit was treated with 10â¯mmolâ¯L-1 GB solution for 10â¯min. The effects of GB treatment on CI, phenolic and soluble sugar metabolism were investigated in this study. Moreover, phenylpropanoid and soluble sugar content, and enzyme activities associated with phenolic and sugar metabolisms were also measured. The results showed that GB reduced CI and maintained high levels of total phenolic and flavonoid content. The activities of phenylpropanoid metabolism-related enzymes were significantly enhanced by GB. Higher content of sucrose and lower contents of fructose and glucose were observed in GB-treated fruits. Therefore, our results showed that GB could enhance chilling tolerance of peach through regulating phenolic and sugar metabolisms, and maintaining high levels of individual phenolic and sucrose content.
Asunto(s)
Betaína/farmacología , Fenoles/metabolismo , Prunus persica/metabolismo , Azúcares/metabolismo , Cromatografía Líquida de Alta Presión , Frío , Fructosa/metabolismo , Frutas/efectos de los fármacos , Frutas/metabolismo , Glucosa/metabolismo , Fenoles/análisis , Fenilanina Amoníaco-Liasa/metabolismo , Prunus persica/efectos de los fármacosRESUMEN
The influence of low-temperature conditioning (LTC) treatment on chilling injury, glycine betaine content, and energy metabolism in loquat fruit at 1 °C storage was investigated. The results indicated that LTC treatment significantly reduced chilling injury index, ion leakage, and malondialdehyde content in loquat fruit. Betaine aldehyde hydrogenase (BADH) activity and endogenous glycine betaine (GB) content in loquats treated with LTC were significantly higher than those in control fruit. Moreover, LTC treatment induced activities of energy metabolism-associated enzymes, including H(+)-adenosine triphosphatase, Ca(2+)-adenosine triphosphatase, succinic dehydrogenase, and cytochrome c oxidase. LTC treatment triggered obviously higher levels of adenosine triphosphate (ATP) content and energy charge in loquat fruit. These results showed that LTC possibly alleviated chilling injury and enhanced chilling tolerance of loquat fruit by enhancing endogenous GB content and energy status.
Asunto(s)
Betaína/análisis , Eriobotrya/química , Conservación de Alimentos/métodos , Frutas/química , Adenosina Trifosfato/análisis , Adenosina Trifosfato/metabolismo , Betaína/metabolismo , Frío , Metabolismo Energético , Eriobotrya/metabolismo , Conservación de Alimentos/instrumentación , Almacenamiento de Alimentos , Frutas/metabolismoRESUMEN
The effects of postharvest ß-aminobutyric acid (BABA) treatment on fruit firmness, pectin degrading enzymes, cell wall constituents and microstructural alterations of pericarp in sweet cherry fruit were investigated. BABA significantly delayed the decline of fruit firmness and inhibited the increase of membrane permeability and the accumulation of malondialdehyde in cherries. The BABA-treated fruit exhibited significantly higher contents of water-soluble pectin, CDTA-soluble pectin, Na2CO3-soluble pectin, total pectin, cellulose and hemicellulose than the control during storage. Activities of pectin degrading enzymes including polygalacturonase and pectinmethylesterase were markedly reduced by BABA treatment. Observations by scanning electron microscopy showed BABA maintained smooth cuticle and integrated structure of subepidermal cell in sweet cherry. These results suggest that the delay in fruit senescence by BABA may be due to depressed membrane permeability and malondialdehyde content, reduced activities of polygalacturonase and pectinmethylesterase, enhanced cell wall polysaccharides content, and integrated subepidermal cell structure in sweet cherry.
Asunto(s)
Aminobutiratos/química , Pared Celular/efectos de los fármacos , Manipulación de Alimentos/métodos , Frutas/efectos de los fármacos , Prunus/química , Pared Celular/química , Frutas/química , TemperaturaRESUMEN
The effects of postharvest oxalic acid (OA) treatment on chilling injury, energy metabolism and membrane fatty acid content in 'Baifeng' peach fruit stored at 0°C were investigated. Internal browning was significantly reduced by OA treatment in peaches. OA treatment markedly inhibited the increase of ion leakage and the accumulation of malondialdehyde. Meanwhile, OA significantly increased the contents of adenosine triphosphate and energy charge in peach fruit. Enzyme activities of energy metabolism including H(+)-adenosine triphosphatase, Ca(2+)-adenosine triphosphatase, succinic dehydrogenase and cytochrome C oxidase were markedly enhanced by OA treatment. The ratio of unsaturated/saturated fatty acid in OA-treated fruit was significantly higher than that in control fruit. These results suggest that the alleviation in chilling injury by OA may be due to enhanced enzyme activities related to energy metabolism and higher levels of energy status and unsaturated/saturated fatty acid ratio.