Firew Tafesse Mamo^{1, 2}, Jonathan Nimal Selvaraj^{1, 2}, Yan Wang^{1, 2}, Yang Liu^{1, 2,}

Aflatoxins (AFs) contamination in food and feed causes health hazards to both humans and animals. Among the Aspergillus species, Aspergillus flavus produces aflatoxin B₁, B₂, G₁ and G₂. AFB₁ is known for its hepatotoxic, teratogenic, mutagenic and carcinogenic nature towards humans and animals. Some A. flavus strains do not produce aflatoxins and are termed as atoxigenic strains. A. flavus also produces an indole-tetramic acid called cyclopiazonic acid (CPA). As aflatoxin contamination can’t be prevented totally, numerous reduction mechanisms have been developed. Applications of atoxigenic A. flavus strains for biocontrol have proved to be a promising method. Hence, it is vital to distinguish A. flavus into toxigenic and atoxigenic strains, for biocontrol application. The atoxigenic strains need to be carefully selected, as the strain isolated and used in the same niche proves effective. The present review analyses the different available methods like cultural, molecular, and analytical methods to identify toxigenic and atoxigenic A. flavus and their precision for the purpose of selecting them as biocontrol agents. This review also highlights the role of CPA, its biosynthetic gene cluster and the methods to detect it and also point out some works on which, atoxigenic strains that also could reduce CPA contaminations. Overall these methods can pave a way to isolate atoxigenic A. flavus free from AFs and CPA, as potential biocontrol agents to be used.

aflatoxins, Aspergillus flavus, cyclopiazonic acid (CPA), atoxigenic strain, toxigenic strains, biocontrol