Utilization of waste fruit-peels to inhibit aflatoxins synthesis by Aspergillus flavus: A biotreatment of rice for safer storage

• Fungus Aspergillus flavus grew and produced aflatoxins in rice on storage.
• Peels of pomegranate and lemon showed appreciable antifungal activity.
• Peels replaced chemical treatments to inhibit aflatoxin production.
• Utilisation of waste peels is economical and safer for long-term storage of rice.
• Use of waste to save a bioresource of economical value.

Antifungal activity in lemon and pomegranate peels was considerable against Aspergillus flavus, higher in pomegranate (DIZ 37 mm; MIC 135 μg/mL). Powdered peels (5, 10, 20% w/w) were mixed in inoculated rice. The inhibitory effect on fungal-growth and production of aflatoxins by A. flavus was investigated at storage conditions – temperature (25, 30 °C) and moisture (18%, 21%) for 9 months. The maximum total aflatoxins accumulated at 30 °C, 21% moisture and at 25 °C, 18% moisture were 265.09 and 163.45 ng/g, respectively in control. Addition of pomegranate-peels inhibited aflatoxins production to 100% during four month-storage of rice at 25 °C and 18% moisture, while lemon-peels showed similar inhibitory effect for 3 months at same conditions. However a linear correlation was observed in aflatoxins level with temperature and moisture. Studies showed that both fruit-wastes are potent preventer of aflatoxin production in rice, useful for a safer and longer storage of rice.