Abstract: In order to explore the effect of cinnamaldehyde fumigation on antioxidant capacity and free polyamines in Lentinus edodes, the cultivar ‘Xianggu 808’ was chosen to undergo cinnamaldehyde fumigation at different concentrations (0, 8, 40 and 80 nmol/L in 30% ethanol). The contents of total phenols and ascorbic acid (AsA), the activity of ascorbate peroxidase (APX), catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR), 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging capacity, total antioxidant capacity and free polyamine content were assayed in the samples. As a result, after storage for 30 days at 4 ℃, the activity of antioxidant enzymes (APX, CAT, SOD and GR), ABTS cation radical scavenging capacity and total antioxidant capacity of all treatment groups were higher than those of the control group, and the best effect was observed with 40 nmol/L cinnamaldehyde. However, cinnamaldehyde treatment had little effect on total phenol content. In addition, the free putrescine content of each treatment group was higher than that of the control group, while the contents of free spermidine and free spermine were lower than those of the control group. Therefore, cinnamaldehyde fumigation treatment can effectively improve antioxidant capacity and stress resistance in shiitake mushroom. This study provides a scientific basis for the application of cinnamaldehyde fumigation in browning control and preservation of fruits and vegetables.

Key words: cinnamaldehyde, shiitake mushroom, antioxidant capacity, free polyamine