Isolation and molecular identification of mycotoxin -producing fungi from fermented milk (nono) samples

Abstract

Milk and milk products are important sources of nutrients to humans as they comprise of water, total solids, carbohydrates, fats, proteins and ash in balanced forms. Dairy products are highly nutritious due to the content and excellent medium for contaminants like molds, bacteria, yeasts and the mycotoxin produced by the molds which poses a great health risk to humans. The aim of the study is to isolate and molecularly identify by PCR, mycotoxin producing fungi from fermented milk (nono) samples. A total of 35 samples of milk comprising thirty fermented milk (nono) and five infant formula processed milk samples were purchased. Isolation and identification of fungi isolates were conducted on PDA and SDA using morphological features. All positive isolates were confirmed using PCR. Four different mold species were isolated from the fermented milk (nono) samples: A. niger (20.8) P. citrinum (18.8), C. cladosporoides (6.2), A. flavus (16.7). Three of the isolates A. niger (27.2), P. citrinum (36.4) and A. flavus (36.4) were also observed in the infant formula processed milk samples. Molecular identification by PCR also revealed the presence of A. niger, P. citrinum and C. cladosporoides. The presence of these mycotoxin-producing fungi poses a great risk to human health most especially children, who are more vulnerable to the disease.