Article

Millets are nutritionally rich and climate-resilient crops widely consumed in India, yet they are highly vulnerable to fungal contamination during post-harvest storage. The present study aimed to isolate potentially mycotoxigenic fungi from stored millet grains collected from major millet-producing regions of India and to evaluate the influence of environmental and nutritional factors on their growth under laboratory conditions. Aged millet samples exhibiting visible fungal infestation were subjected to standard mycological isolation techniques using potato dextrose agar. The dominant fungal genera identified based on morphological characteristics were Aspergillus, Fusarium, and Penicillium, with Aspergillus species occurring most frequently across all sampling sites. Optimization studies revealed that potato dextrose agar supported maximum radial growth of fungal isolates compared to other tested media. Temperature significantly influenced fungal growth, with optimal growth observed at 27–30 °C, while growth declined at higher and lower temperatures. The isolates exhibited maximum biomass production under slightly acidic conditions, particularly at pH 5.5–6.5. Incubation period studies indicated peak fungal growth between 7 and 10 days. Among nutritional factors, glucose and sucrose were the most favorable carbon sources, while yeast extract and peptone supported higher biomass production compared to inorganic nitrogen sources. The optimized growth conditions closely resemble traditional grain storage environments in rural India, highlighting a substantial risk of fungal proliferation and potential mycotoxin contamination in stored millets. The findings emphasize the need for improved post-harvest handling, storage practices, and regular monitoring to ensure the safety and quality of millet and millet-based food products.