Characterization of Lactobacillus, Bacillus and Saccharomyces isolated from Iranian traditional dairy products for potential sources of starter cultures

Abstract

The aim of the present study was to investigate technological properties of starter strains from traditional dairy products collected from five villages of Lorestan province in Iran. Thirty five samples were cultured on selective media (MRS broth, Nutrient Broth and YGC and then typical colonies checked for morphological features and eventually eighty two strains selected for further examination. The strains were evaluated for Hydrolysis of casein, starch and citrate, growth at 15 and 45 °C, growth in 4 and 6.5% NaCl, resistance to antibiotics (ampicillin, bacitracin, chloramphenicol, erythromycin, gentamicin, penicillin, novobiocin, nalidixic acid) proteolytic and lipolytic and acidification activities. Sixteen strains chosen according to the difference in cell morphology and were identified using API galleries and ability to metabolize various carbohydrates, which consequently, led to identifying seven Lactobacillus casei, five Lactobacillus plantarum, two Saccharomyces cerevisiae and two Bacillus subtilis. In general, two strains of L. casei AKL2, DDL2, two strains of L. plantarum SYL5, ACL4 and one strain of S. cerevisiae DDy2 was demonstrated the most important technological characterization that suitable for using as starter cultures.

Keywords: Bacillus; Lactobacillus; Saccharomyces; starter cultures; technological properties.

Figure 1.. The pH changes at time intervals between 0 and 24 h in acidification test.