Synergistic effect of salicylic acid and chitosan on postharvest life and quality attributes of jamun (Syzygium cumini Skeels) fruit

Syzygium cumini Skeels, commonly known as jamun, is an under-utilized fruit crop, native to India. The fruit is rich in several bioactive compounds and possesses several medicinal properties, especially therapeutic effects towards healing diabetes. However, the fruit deteriorates rapidly after harvest and can only be stored for 2-3days at ambient conditions. Therefore, the present study was conducted to extend the storability and preserve jamun fruit quality during storage at ambient conditions. Fully ripe jamun fruits were immersed in salicylic acid (SA, 1.0mM or 1.5mM) or chitosan (1.5% w/v) solutions either alone or in combination. Fruits dipped in distilled water served as control. Following treatments, fruits were dried in air and stored at room temperature in corrugated fibre board boxes. The results indicated that 1.5% chitosan +1.5mM SA treatment was highly effective in preserving fruit quality and delaying senescence. This treatment resulted in about 19.5% lower weight loss, 49.9% lower decay loss, and 48% lower malondialdehyde content than control fruit. Combined treatment of chitosan and SA (1.5mM) retained about 1.34-fold higher total anthocyanins, 1.69-fold higher total phenolics, 1.5-fold higher total flavonoids, 1.75-fold higher total antioxidant capacity, and 1.5-fold higher radical scavenging activity than control up to 6day storage. Significant variations in ascorbic acid and titratable acidity were not recorded among salicylic acid-treated and chitosan-coated fruits; however, total soluble solids content was highest in chitosan-coated fruits. The findings of the study will be useful to increase the availability of jamun fruit and enable for its long-distance transport and subsequent marketing.