Isoamyl isothiocyanate influences the oxidation-antioxidant homeostasis to maintain the postharvest quality of truffles (Tuber indicum)

Truffles are highly susceptible to postharvest quality deterioration, primarily manifested as dehydration, microbial spoilage, and tissue softening. Isopropyl isothiocyanate (IAITC), as a volatile antimicrobial compound, exhibits multifaceted potential in the field of postharvest preservation of agricultural products. However, the effect of IAITC on postharvest truffles remains inconclusive. In this study, truffles were fumigated with 0, 5, 15, and 30 µL L-1 IAITC, and measuring quality indicators combined with the comprehensive evaluation were conducted. Results showed that different concentrations of IAITC maintained nutrition, and retained sensory quality compared with the control group. Among the treatment groups, the 15 µL L-1 IAITC exhibited the best effect on improving postharvest fruit quality. At this concentration, IAITC maintained water content, and weight, inhibited bacterial growth and enhance the activity of antioxidant enzymes (CAT and SOD), thereby maintained ROS homeostasis. Concurrently, firmness, ASA, and soluble sugar (SS) were increased under 15 µL L-1 IAITC treatment. In addition, the pearson correlation analysis-PCA score plot indicated that different concentrations of IAITC had differential effects on postharvest of the truffles, following the order 15 > 5 > 30 µL L-1. Collectively, these findings suggest that IAITC maintains the storage quality of truffles by simultaneously improving ROS homeostasis and suppressing microbial growth.