Abstract:Changes in cell wall enzyme activity are known to significantly affect pectin degradation and fruit softening. Changes in the pectin content and activity of cell wall polysaccharide-degrading enzymes (PE, exo-PG, endo-PG, and EG) during low-temperature storage (0 ℃ and 10 ℃) of “banbianhong” plum were investigated in this study. Correlation analysis was carried out to explore the effect of cell wall enzyme activity on pectin degradation. The results showed that the changes in the activities of four cell wall enzymes were different during low-temperature storage, indicating that lower temperatures inhibited enzyme activity to a certain extent. PE activity showed significant difference after 5 days storage under 0 ℃ and 10 ℃, while significant differences were found in exo-PG activity during the entire storage period. When the plum was stored at 0 ℃ and 10 ℃, activities of endo-PG and EG did not show significant difference during the first 10 days and the trend of changes in endo-PG activity was similar to that of EG, however, the peak value of endo-PG activity appeared later than that of EG. The results of correlation analysis between pectin content and cell wall enzyme activity showed that protopectin and SSP content showed a significant negative correlation with WSP content. The activity of PE exhibited a significant positive negative correlation with ASP and HSP content. Thus, PG played an important role in the conversion process from protopectin and SSP to WSP, while EG played a minor role on the degradation of pectin in plums.
