Effects Of Bio-preservative Agents On The Postharvest Physiology And Quality Of Pepper

The effects of1,5-Gluconolactone (GDL), chitosan and anti-bacterial peptide (ABP) on postharvest physiology and quality of pepper (cv. Sujiao No.5) stored at room temperature were investigated in order to understand the possibility and preservation mechanism of the substances appling to vegetables. The main results were as follows:1Peppers (cv. Sujiao No.5) were dipped into individual GDL (0.2%,0.6%,1.0%), chitosan (0.5%,1.0%,1.5%) and ABP (origanial solution,5-fold diluent,10-fold diluent), respectively, and then held at15+5℃to investigate the effect of these sbstances on fresh-keeping. The results showed that higher concentrations of GDL or chitosan were more beneficial for pepper storage, however ABP had different result for high concentration. All concentrations of3bio-preservative substances could effectively suppress respiration, decay and weight loss, delay the degradation of chlorophyll and vitamin C, and maintain higher POD activity. Based on the determinated data, the main effect of each substance was:GDL could effectively inhibit the decay and maintain high POD activity of peppers; Chitosan could slow down the respiratory rate and Vc and prevent chlorophyll loss; ABP was most remarkable in controlling decay.1.0%GDL,1.5%chitosan and original ABP fermented solution was the best concentration used in practice for each individual application. The storage life of peppers could be double by the treatment of selected concentration.2The orthogonal experiment of0.2%,0.6%and1.0%GDL,1.0%,1.5%and2.0%chitosan, and original fermented solution,5-fold and10-fold diluent ABP at25±5℃was carried out to select the best combination of the3substances. The combined treatment could effectively inhibit the accumulation of MDA, protect the integrity of cell membranes, and maintain POD and CAT activities and then remove the reactive oxygen species and free radicals. All these results indicate that the3bio-preservatives were beneficial for the storage of the peppers. The best combination was1.0%GDL,2.0%chitosan and5-fold ABP diluent, with the greatest importance of GDL on the storage of thel peppers.