Abstract:

Huangguan pears were used as materials to investigate the changes of carbohydrate metabolism and related enzyme activities of postharvest fruits. Huangguan pears were stored at 0 ℃ and relative humidity of 85%－95%. The contents of glucose, sucrose, total soluble solid and titratable acid, and the activities of acidic invertase (AI), neutral invertase (NI), sucrose synthase (SS) and sucrose phosphate synthase (SPS) were measured. Results showed that the content of glucose and activities of AI and NI exhibited an initial increase and a following decrease. An obvious high peak of AI was observed. However, the content of sucrose and activities of SS and SPS exhibited a decrease during storage. As the important index of fruit flavor, the content of TA exhibited a decrease trend, while the content of TSS exhibited an up-down-up trend during storage. Net synthesis activities of enzymes involved in carbohydrate metabolism were closely related to the content of sucrose during storage.

Key words: Huangguan pear, carbohydrate metabolism, invertase, sucrose synthase, sucrose phosphate synthase