Traditionally fermented foods such as, ‘Corn Pap’ (fermented corn paste), “Kum-kum” (fermented cassava-derived powder), ‘Water fufu’ (Fermented cassava-derived paste), and Soya beans yogurt (processed from fermented soya beans), have an old history in Cameroon and are staple foods largely consumed on daily basis by majority of both young and elderly people in the main cosmopolitan cities such as Yaounde, Douala, Bamenda and Buea, where majority of the ethnic groups in Cameroon reside. Lactic acid bacteria (LAB) have been used in the production of fermented foods and bacteriocins produced by these bacteria are harmless and have the ability to inhibit the growth of pathogenic bacteria. The aim of this study was to screen and identify genotypically bacteriocinproducing lactic acid bacteria from locally fermented foods in Cameroon against two food born Salmonella enterica pathogens and to assess the phylogenetic relationship among the isolates. A total of 112 fermented food samples were obtained randomly from different local foods markets in the four main cities in Cameroon. All the samples were cultured in the De man, Rogosa, and Sharpe (MRS) medium which supports the growth of lactic acid bacteria. A total of 70 isolates were found to be Grampositive and catalase-negative and were further identified by using polymerase chain reaction (PCR) targeting the 16S rRNA gene. Genomic DNA of bacteria isolates were extracted using EZ-10 spin column genomic DNA Extraction kit and amplification of 16SrRNA gene of bacterial isolates was done using the bacteria universal MP096 forward and reverse primers and sequencing was carried out at Genewiz, NJ, USA. Selection for DNA sequencing was based on their bacteriocin-producing potentials which produced inhibition zones on culture plate. Sequence analysis was carried out using BLAST program and comparison with the resources at the NCBI database. Phylogenetic tree was constructed to determine the closest bacterial species and strains by Neighbour Joining method using MEGA X software, version 10.0.5. Results showed that 70 PCR-amplified products were obtained which revealed clear single bands of presumed LAB isolates on 1.5% (w/v) agarose gel with average molecular weights in the range of 800bp-1300bp. The sequencing results identified 23 lactic acid bacteria strains (34.9%) which had similarity over 90% with those deposited in the NCBI GenBank. The isolates were identified as; L. plantarum (9 strains), Uncultured L. spp (4 strains), L. paraplantarum (3 strains), L. pentosus (2 strains), L. salvarius (2 strains), Pediococcus acidilactici (2 strains) and 1 strain belong to Pediococcus cellicola. There was a significant difference (P<0.05) in the number of isolates obtained from Corn pap compared to the other fermented food sources. The highest number of isolates were obtained from Corn pap sample (9), followed by 5 each from Kumkum and Soyabeans, and 4 from Water fufu samples. Results also showed genetic relationship of isolates from Yaounde, Douala and Bamenda to have ancestry from isolate obtained from Buea. Therefore, this study has shown the presence of different LAB bacterial strains in the fermented foods and constitute potential sources of bacteriocinogenic LAB against Salmonella Typhimurium and S. Enteritidis. The distribution of the strains from Bamenda, Douala and Yaounde, were extremely likely to originate from the strain, Lactiplantibacillus plantarum strain 07B144, obtained from Buea.

Keywords : Bacteriocinogenic; Isolation; Lactic Acid Bacteria; Molecular Identification; Phylogenetic Analysis; Salmonella Enterica; Traditionally Fermented Foods.