Effects of novel antimicrobial peptide F1 on quality and storage stability of litchi fruit

Litchi, a fruit of considerable commercial value, is highly susceptible to postharvest deterioration. Chemical preservatives pose potential risks to consumer health and the environment. Therefore, there is an urgent demand for natural preservative alternatives.

This study investigates the efficacy of an antimicrobial peptide extract (AMS) as a natural preservative for litchi. Fruit samples were immersed in distilled water (control), sodium hypochlorite, prochloraz, or AMS solutions at varying concentrations (0.5 and 1.0 mg mL^-1), then stored at room temperature. Our results indicated that 1.0 mg mL^-1 AMS predominantly maintained the pericarp polyphenol and flavonoid contents during the middle stage of storage and inhibited peroxidase activity, whereas 0.5 mg mL^-1 AMS exerted similar protective effects on polyphenols and flavonoids during the late stage and suppressed polyphenol oxidase activity. Compared to the control group, 0.5 mg mL^-1 AMS effectively delayed the reduction in vitamin C content of pulp and the color deterioration of the pericarp, and 1.0 mg mL^-1 AMS significantly reduced the microbial load on the litchi pericarp, thereby inhibiting microbial-induced decay. The results of correlation analysis and principal component analysis indicate a strong link between microbial load and quality deterioration in litchi. As a biological preservative, AMS may preserve litchi fruits by inhibiting microbial growth, along with other mechanisms, with a different preservation effect on fruit quality compared to traditional chemical preservatives.

The results indicate that AMS can be applied as a safe and effective natural preservative for postharvest storage and preservation of litchi. This study contributes to enhancing food safety in litchi and supports the development of green food preservation technologies. © 2026 Society of Chemical Industry.