Modification of matrix polysaccharides during avocado (Persea americana) fruit ripening: an assessment of the role of Cx-cellulase.

摘要: The role of Cx-cellulase (EC 3.2.1.4) in fruit ripening and softening is unknown. In the present study, avocado (Persea americana) fruit, a rich source Cx-cellulase, were examined to determine if enzyme plays ripening-related hemicellulose metabolism. Hemicelluloses (4 M alkali-soluble) from exhibited very broad distribution polymer sizes an overall decrease Mr during ripening. Polymers affected primarily those large (relative molecular mass). characteristic total changes with also evident for xyloglucan (XG), putative substrate Cx-cellulase. Hydrolytic activity toward hemicelluloses preripe was detected crude buffer-soluble protein extracts derived ripe mesocarp tissue. XG degraded, pattern similar that observed Purified against specific components isolated hemicelluloses; however, contrast protein. alone without influence on XG. Protein depleted capable moderate depolymerization. We conclude studies not involved depolymerization fruit.