Banana fruit of cv. Gros Michel (Musa acuminata, AAA Group, locally called cv. Hom Thong) and cv. Namwa (Musa × paradisiaca, ABB
Group) were immersed for 5, 10 and 15 min in water at 42 ◦C, or in water at 25 ◦C (control), and were then stored at 4 ◦C. Hot water treatment for
15 min delayed peel blackening during cold storage by about 4 days in cv. Gros Michel and by 2 days in cv. Namwa. In both cultivars the delay of
blackening was correlated with an increase in the ratio of unsaturated to saturated fatty acids. Hot water treatment in cv. Gros Michel but not cv.
Namwa was correlated with lower lipoxygenase (LOX) activity and lower levels of thiobarbituric acid-reactive compounds. The results suggest
that the rapid peel blackening of cv. Gros Michel is related to detectable membrane degradation, whereas the membrane-associated changes might
be below the detection limit in the slower blackening cv. Namwa. The delay of peel blackening in cv. Gros Michel was associated with reduced
expression of a catechol oxidase gene, which might partially explain the lower catechol oxidase activity after hot water treatment. The hot water
treatment also increased the abundance of a Hsp70 transcript. The changes in gene expression found in cv. Gros Michel were not observed in cv.
Namwa. Taken together the delay of blackening by hot water treatment in cv. Namwa was only correlated with a change in the ratio of unsaturated
to saturated fatty acids, whereas that in cv. Gros Michel was additionally correlated with lower LOX activity, lower mRNA abundance of a gene
encoding a catechol oxidase and lower catechol oxidase activity.
© 2007 Elsevier B.V. All rights reserved.
Banana fruit of cv. Gros Michel (Musa acuminata, AAA Group, locally called cv. Hom Thong) and cv. Namwa (Musa × paradisiaca, ABBGroup) were immersed for 5, 10 and 15 min in water at 42 ◦C, or in water at 25 ◦C (control), and were then stored at 4 ◦C. Hot water treatment for15 min delayed peel blackening during cold storage by about 4 days in cv. Gros Michel and by 2 days in cv. Namwa. In both cultivars the delay ofblackening was correlated with an increase in the ratio of unsaturated to saturated fatty acids. Hot water treatment in cv. Gros Michel but not cv.Namwa was correlated with lower lipoxygenase (LOX) activity and lower levels of thiobarbituric acid-reactive compounds. The results suggestthat the rapid peel blackening of cv. Gros Michel is related to detectable membrane degradation, whereas the membrane-associated changes mightbe below the detection limit in the slower blackening cv. Namwa. The delay of peel blackening in cv. Gros Michel was associated with reducedexpression of a catechol oxidase gene, which might partially explain the lower catechol oxidase activity after hot water treatment. The hot watertreatment also increased the abundance of a Hsp70 transcript. The changes in gene expression found in cv. Gros Michel were not observed in cv.Namwa. Taken together the delay of blackening by hot water treatment in cv. Namwa was only correlated with a change in the ratio of unsaturatedto saturated fatty acids, whereas that in cv. Gros Michel was additionally correlated with lower LOX activity, lower mRNA abundance of a geneencoding a catechol oxidase and lower catechol oxidase activity.© 2007 Elsevier B.V. All rights reserved.
การแปล กรุณารอสักครู่..
