关键词: 杏鲍菇, 乙烯, 衰老, 抗氧化能力

Abstract: This study was carried out in order to understand the maturation and senescence mechanism of Pleurotus eryngii and its sensitivity to ethylene. The pattern of endogenous ethylene production in Pleurotus eryngii under normal temperature (20 ± 1) ℃ and 70%–80% relative humidity was investigated, and the effect of exogenous ethylene treatment (1, 10, 100 or 1 000 μL/L) on the endogenous ethylene production in postharvest P. eryngii and its senescence process was determined. The results indicated that the biosynthesis of ethylene gradually increased with the maturation of P. eryngii during postharvest storage and exhibited a peak at 12 h and 36 h of storage, respectively. Furthermore, the two peak values were increased by 12.53 and 7.57 times, respectively, when compared with the sporophores before storage (0 h). Meanwhile, exogenous ethylene treatments accelerated endogenous ethylene production in P. eryngii, delayed the endogenous ethylene production peak, increased PPO (polyphenol oxidase) and PAL (phenylalanine ammonia-lyase) activities; moreover, exogenous ethylene treatments maintained higher browning degree, promoted the increase of relative electrical conductivity and MDA (malondialdehyde) content and the degradation of soluble sugar and protein, decreased APX (ascorbate peroxidase), CAT (catalase), POD (peroxidase) and SOD (superoxide dismutase) activities, accelerated the decrease in DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging capacity and total antioxidant capability (T-AOC), and maintained lower levels of total phenol and flavonoid contents. In conclusion, exogenous ethylene treatments could significantly accelerate the senescence of postharvest P. eryngii. These findings will be helpful to reveal the regulatory mechanism of ethylene on the ripening and senescence of edible mushrooms.

Key words: Pleurotus eryngii, ethylene, senescence, antioxidant capability