Characterization and technological properties of predominant lactic acid bacteria isolated from traditional fermented foods from Ecuador.

Abstract

Ninety-six samples of traditional fermented foods were collected from 20 Ecuadorian provinces. A total of 119 lactic acid bacteria (LAB) were isolated and characterized by phenotypic and 16S ribosomal DNA (rDNA). 47% of isolates were identified as facultative heterofermentative Lactobacillus sp. The next predominant groups of lactic acid bacteria (31%) were homofermentative cocci belonging to the genera Pediococcus, Lactococcus and Enterococcus; 11%. were obligate heterofermentative bacteria such Lactobacillus sp. and 11% heterofermentative cocci (Weissella and Leuconostoc). Biochemical properties such as production of bacteriocin, exopolysaccharide (EPS), proteinases and acidification, were evaluated in vitro with the purpose of identification of potential starter strains. The most of strains (82%) showed caseinolytic activity; contrastingly EPS and bacteriocin production were a rare trait. This manuscript represents the first characterization of traditional Ecuadorian fermented foods-associated LAB, using phenotypic and genetic approaches.