The present study aimed at determining the histamine production capacity of Gram (+) and Gram (−) bacteria isolated from
Octopus maya, along with identifying the presence of amino acid decarboxylase genes. Of the total 80 psychrotrophic microorganisms, 32 strains were identified as
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The present study aimed at determining the histamine production capacity of Gram (+) and Gram (−) bacteria isolated from
Octopus maya, along with identifying the presence of amino acid decarboxylase genes. Of the total 80 psychrotrophic microorganisms, 32 strains were identified as histamine-forming bacteria. The recombinant DNA technique was used for genotypic identification of histidine (
hdc), ornithine (
odc), and lysine decarboxylases (
ldc) genes. Thirty-two strains were able to produce 60–100 ppm in trypticase soy broth with 1.0%
l-histidine after 6 h at 20 °C. NR6B showed 98% homology with
Hafnia alvei. NR73 represented 18.8% of the total isolates and showed 98% homology with
Enterobacter xianfengensis and
Enterobacter cloacae. NR6A represented 6% of the total isolates, which were identified as
Lactococcus sp. The
hdc gen from NR6B showed 100% identity with
hdc from
Morganella morganii;
ldc showed 97.7% identity with
ldc from
Citrobacter freundii. The
Odc gene was detected only in NR73 and showed 100% identity with
Enterobacter sp. All the isolated were identified as weak histamine–former. The ingestion of a food containing small amounts of histamine has little effect on humans; however, the formation of biogenic amines is often considered as an indicator of hygienic quality; this emphasizes the importance of improving good management practices and storage.
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