Isolation and characterization of lactic acid bacteria from "ting" in the Northern Province of South Africa

Abstract

Traditional fermented food, especially fermented maize and sorghum represents an important part of the diet of peri-urban and rural communities in South Africa. In this study a survey was conducted to determine the popularity and utilization of “Ting” in the Limpopo Province of South Africa. The following areas were selected for the study: Venda, Giyani, Bolobedu and Polokwane. Ting samples were collected from different areas and from different local families. Gram positive, catalase-negative, oxidase negative, non-motile cells were presumptively identified as lactobacilli. Isolates were assigned to a genus on the basis of key characteristics. Growth at 10, 15 and 45oC in MRS broth wase evaluated visually after 72h of incubation. Tests for the catalase reaction, production of gas from glucose and growth at 7 and 10% NaCl concentrations were performed. API 50CHL medium and API 50CH strips were used to identify all the isolates to species level. Microorganisms from “Ting” fermented from both sorghum and maize were bacteria, which belong to the genus Lactobacillus, Leuconostoc and Pediococcus. Lactobacillus pentosaceus, and Lactobacillus plantarum, Lactobacillus pentosaceus were dominant in the fermentation of maize, while Lactobacillus cellobisus, Leuconostoc mesenteroides, Lactobacillus collinoides, Lactobacillus brevis, Lactobacillus fermentum and Lactobacillus curvatus were identified as bacteria from fermented “Ting” sorghum. The use of polyacrylamide gel electrophoresis (PAGE) of total soluble proteins, together with computer analysis was used to analyse the resultant protein profiles. L. plantarum, L. pentosus and P. pediococcus were the most dominant isolates.