Abstract

Mexican Tuba (M‐Tuba) and Tepache are Mexican fermented beverages prepared mainly with pineapple pulp and coconut palm, respectively. At present, reports on the microbiota and nutritional effects of both beverages are lacking. The purpose of this study was to determine whether M‐Tuba and Tepache contain cultivable lactic acid bacteria ( LAB ) capable of producing bacteriocins. Tepache and M‐Tuba contain mesophilic aerobic bacteria, LAB , and yeast. B acillus subtilis , L isteria monocytogenes , L isteria innocua , S treptococcus agalactiae , S taphylococcus aureus , E scherichia coli , K lebsiella pneumoniae , S almonella typhimurium , and Salmonella spp , were the microorganisms most susceptible to metabolites produced by bacterial isolates. M‐Tuba and Tepache contain bacteria that harbor genes coding for nisin and enterocin, but not pediocin. The presence of L actococcus lactis and E . faecium in M‐Tuba and Tepache, was identified by 16S rDNA . These bacteria produced bacteriocins of ~3.5 kD a and 4.0–4.5 kD a, respectively. Partial purified bacteriocins showed inhibitory effect against M icrococcus luteus , L . monocytogenes , L . innocua , S tr. agalactiae , S . aureus , B acillus cereus , B . subtilis , E . faecalis , and K . pneumoniae . We characterized, for the first time, cultivable microbiota of M‐Tuba and Tepache, and specifically, identified candidate lactic bacteria ( LAB ) present in these beverages that were capable of synthesizing antimicrobial peptides, which collectively could provide food preservative functions.

We studied the cultivable bacteria of M exican T uba ( M ‐ T uba) and T epache, two M exican fermented beverages. M ‐ T uba and Tepache are a source of bacteriocinogenic lactic acid bacteria that produce N isin and E nterocin as antimicrobial peptides. Bacterial isolates showed inhibitory effect against food‐borne pathogenic bacteria.