RESUMO
The aim of this study was to characterize potential probiotic strain co-producing α-amylase and ß-galactosidase. Sixty-three strains, isolated from pickle samples were screened for their hydrolase producing capacity by utilizing different starches as carbon source. One out of 63 strains, isolated from traditionally fermented pickled yam showing maximum hydrolase activity (α-amylase (36.9 U/ml) and ß-galactosidase (42.6 U/ml)) within a period of 48 hours was identified as Lactococcus lactis subsp. lactis. Further, it was assessed for the probiotic characteristics under gastrointestinal conditions like acidic, alkaline, proteolytic enzymes, bile stress and found to exhibit tolerance to these stresses. The therapeutic potential of the isolate is implicated because of its antagonistic effect against enteric foodborne pathogens (Salmonella typhimurium, Escherichia coli 0157:H7, Staphylococcus aureus, Yersinia enterocolitica and Aeromonas hydrophila). The results of this study entail a potential applicability of the isolate in developing future probiotic foods besides the production of industrially significant hydrolases.
Assuntos
Dioscorea/microbiologia , Alimentos em Conserva/microbiologia , Lactococcus lactis/enzimologia , Tubérculos/microbiologia , Probióticos/metabolismo , alfa-Amilases/metabolismo , beta-Galactosidase/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/economia , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Dieta/etnologia , Digestão , Dioscorea/química , Farmacorresistência Bacteriana Múltipla , Alimentos em Conserva/economia , Indústria de Processamento de Alimentos/economia , Suco Gástrico/microbiologia , Índia , Resíduos Industriais/economia , Lactococcus lactis/efeitos dos fármacos , Lactococcus lactis/crescimento & desenvolvimento , Lactococcus lactis/isolamento & purificação , Interações Microbianas , Viabilidade Microbiana , Suco Pancreático/microbiologia , Tubérculos/química , Probióticos/economia , Probióticos/isolamento & purificação , Amido/economia , Amido/metabolismo , alfa-Amilases/economia , alfa-Amilases/isolamento & purificação , beta-Galactosidase/economia , beta-Galactosidase/isolamento & purificaçãoRESUMO
Fried sourdough bread (bhatura) with an elevated amount of γ-aminobutyric acid (GABA) was produced using lactic acid bacteria (LAB). The LAB starter was screened and isolated from pickled yam showing highest GABA content and was identified as Lactococcus lactis subsp. lactis. The maximum GABA production in de Man Rogosa Sharpe (MRS) media supplemented with monosodium glutamate (MSG) was 110 mg/100 ml at pH 5, and 1-3% NaCl did not change the production of GABA significantly (p>0.05). When MSG was replaced with Vigna mungo in sourdough, the amount of GABA for bhatura was 226.22 mg/100 g representing about 10-fold increase. A sensory evaluation resulted as the overall general acceptability of bhatura to be 4.91 ± 0.03 on a five-point hedonic scale. Thus, the results indicated the potential of L. lactis as a LAB starter for the production of GABA-enriched bhatura. Although other physiological effects can be expected in the product, animal and clinical studies are mandatory prior to application of this food.