ANTIMYCOTIC AND ANTIAFLATOXIGENIC EFFECT OF LACTIC-ACID BACTERIA - A REVIEW

Lactic acid bacteria are extensively used in the fermentation of a wid e variety of food products and are known for their preservative and th erapeutic effects. Many lactic acid bacteria species have been reporte d to inactivate bacterial pathogens, and numerous antibacterial substa nces have been isolated. However, the antimycotic and antimycotoxigeni c potential of lactic acid bacteria has still not been fully investiga ted. Fermented foods such as cheese can be contaminated by molds and m ycotoxins. Mold causes spoilage and renders the product unusable for c onsumption, and the presence of mycotoxins presents a potential health hazard. A limited number of reports have shown that lactic acid bacte ria affect mold growth and aflatoxin production. Although numerous lac tic acid bacteria such as Lactobacillus spp. were found to inhibit afl atoxin biosynthesis, other lactic bacteria such as Lactococcus lactis were found to stimulate aflatoxin production. The morphology of lactic acid bacteria cells has also been found to be affected by the presenc e of fungal mycelia and aflatoxin. Lactococcus lactis cells became lar ger and formed long chains in the presence of Aspergillus flavus and a flatoxins. Numerous investigations reported that low pH, depletion of nutrients, and microbial competition do not explain the reason for afl atoxin inhibition. Some investigators suggested that the inhibition of aflatoxin is due to lactic acid and/or lactic acid bacteria metabolit es. These metabolites have been reported to be heat-stable low-molecul ar-weight compounds.