Mycotoxin contamination in stored cereals and its mitigation through biocontrol agents

Abstract:

While chemical fungicides can suppress mould growth in stored grain, they leave residues that raise food safety concerns of their own a contradiction that has driven interest in biological alternatives. This research surveyed mycotoxin contamination levels in wheat, rice, and maize stored under farm conditions in Nakuru County, Kenya, and then tested two biocontrol agents Trichoderma afroharzianum (strain T-22) and Lactobacillus buchneri (strain LB-01) for their ability to reduce aflatoxin B1 in artificially inoculated grain over a 60-day storage period. Among the 90 grain samples surveyed, 67% exceeded the KEBS regulatory limit for at least one mycotoxin, with aflatoxin B1 being the most prevalent (38.4% of total detections). In the mitigation trial, T. afroharzianum at 2.0 g/kg achieved 68.1% aflatoxin reduction, while L. buchneri at the same dose reached 55.3%. Neither agent altered grain moisture or germination rate. The results suggest that T. afroharzianum is a practical biocontrol option for aflatoxin management in on-farm cereal storage where chemical treatments are undesirable.