Pectinesterase, polygalacturonase, and beta-galactosidase during softening of ethylene-treated kiwifruit
1992
Wegrzyn, T.F. | MacRae, E.A.
The activities of several cell wall-associated enzymes of the outer pericarp were assayed during softening of kiwifruit [Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson var. deliciosa cv. Hayward] treated with ethylene. The activity of polygalacturonase (EC 3.2.1.15) increased slightly during fruit softening, while beta-galactosidase (EC 3.2.1.23) activity remained constant. Salt-extracted pectinesterase (EC 3.1.1.11) activity increased during ethylene treatment, then dropped rapidly to low levels as fruit softened. Residual pectinesterase activity, extracted after digestion of the cell wall pellet with a fungal enzyme mix, decreased on softening. The rapid softening of kiwifruit in response to ethylene treatment may be initiated by an induction of pectinesterase activity, causing increased de-esterification of cell wall pectins, followed by degradation of solubilized pectin.
显示更多 [+] 显示较少 [-]