COMPARATIVE EFFECTS OF POSTHARVEST MITIGATION TREATMENTS ON MYCOTOXINS PRODUCTION POTENTIAL OF ASPERGILLUS PARASITICUS IN MANGO (MANGIFERA INDICA L.) FRUIT

Abstract

This study focused on comparative effects of post-harvest low-to-high γ-irradiation doses (0.5–1.5 kGy), UV-C (30-60 min) and hot water treatments (55 ˚C for 5 min) upon spoilage of mango (Mangifera indica L.)fruit cv. Kala Chunsa by fungal infections. Thirteen fungal species belonging to five genera were isolated from diseased mango fruits surface. Aspergillus species were the most predominant followed by Penicillium and Fusarium. The aflatoxins AFB₁, AFB₂, AFG₁ and AFG₂ produced by A. parasiticus isolates on yeast extract sucrose (YES) medium for un-treatedmango fruits was found 1.789, 0.52, 0.296 and 0.85 ppb, respectively. The increase in post-harvest γ-irradiation dose showed a high suppression of aflatoxins production (p≤0.05). Fruits treated with UV-C for 30 min showed higher aflatoxins production than fruits treated for 60 min (p≤0.05). The treatment of fruits with hot water also showed remarkable reduction in aflatoxins levels with respect to UV-C doses and control (p≤0.05). The results of this study demonstrated that treatment of mango fruit surface with post-harvest γ-irradiation dose (1.5 kGy / 2 hour and 15 minutes) or hot water (55 ˚C for 5 min) can inhibit the production of toxigenic aflatoxins. In conclusion, irradiation of fresh fruits such as mango can be effectively used on a practical scale to increase the international trade.