METHOD FOR ASSESSMENT OF TOXIN-FORMING CAPABILITY OF AFLATOXIGENIC STRAIN Russian patent published in 2022 - IPC G01N33/577 C12Q1/06 C12Q1/6895 C12N1/14 

FIELD: biology.

SUBSTANCE: present invention relates to the field of biology and, in particular, relates to assessment of toxin-forming capability of an aflatoxigenic strain. The method includes measurement of the yield of aflatoxin and transcription activity of gene Nor-1 of Aspergillus flavus strains for obtaining a ratio of the yield of aflatoxin to transcription activity of gene Nor-1, and assessment of toxin-forming capability of the aflatoxigenic strain. Toxin-forming capability of the aflatoxigenic strain is denoted as Y, the ratio of the yield of aflatoxin to transcription activity of gene Nor-1 (AFT/Nor-1) is denoted as X with calculation by the formula Y = 10.14X – 16.20. At the same time, for a highly toxigenic strain, toxin-forming capability is > 150 ng/ml; for a moderately toxigenic strain: 50 < toxin-forming capability < 150 ng/ml; for a low toxigenic strain: toxin-forming capability is < 50 ng/ml. The above-mentioned values are substituted to the formula for obtaining a range of assessment of toxin-forming capability with assessment of toxin-forming capability of the aflatoxigenic strain in accordance with the ratio of the yield of aflatoxin to transcription activity of gene Nor-1 (AFT/Nor-1). Moreover, AFT/Nor-1>16.4 indicates the highly toxigenic strain; 6.5<AFT/Nor-1<16.4 indicates the moderately toxigenic strain; 0<AFT/Nor-1<6.5 indicates the low toxigenic strain. The ratio of the yield of aflatoxin to transcription activity of gene Nor-1 (AFT/Nor-1) is obtained by means of two of the proposed methods.

EFFECT: invention provides quick and accurate assessment of toxin-forming capability of Aspergillus flavus strain, so that this method is important for early prevention and control of pollution with aflatoxin; in addition, the developed method for simultaneous detection based on RT-PCR for indicators of the yield of aflatoxin and transcription activity of gene Nor-1 with the result of AFT/Nor-1 is reliable and accurate, and it can be used as an identification index for determination of toxin-forming capability of Aspergillus flavus strain.

6 cl, 6 dwg, 6 tbl