Identification and in vitro assessment of potential probiotic characteristics and antibacterial effects of Lactobacillus plantarum subsp. plantarum SKI19, a bacteriocinogenic strain isolated from Thai fermented pork sausage

Abstract

A total of 2257 lactic acid bacteria were preliminarily screened for antagonistic activity against subsp. JCM 1157. Strain SKI19 was selected and identified at the subspecies level as subsp. SKI19, using rRNA gene sequence analysis combined with and genes' amplification. Antibacterial activity of SKI19 was completely lost after treatment of neutralized cell free culture supernatant with proteolytic enzymes, suggesting that SKI19 produced a bacteriocin-like substance that inhibited not only closely related species, but was also effective against DMST 17303. Viewed under scanning electron microscope, cell membranes of the indicator strain appeared to collapse after exposure to the bacteriocin-like substance. In vitro tests concerning probiotic properties, SKI19 survived under simulated gastrointestinal tract conditions, and adhesion of its cell surface to xylene and chloroform was 90.14 and 89.85%, respectively. Complete inhibition by SKI19 against pathogenic bacteria ( DMST 4212, DMST 17303, and DMST 8840) was observed in co-cultivation under anaerobic conditions. A safety assessment showed that SKI19 was susceptible to several antibiotics and had no haemolytic activity. PCR amplification of virulence factors with the specific primers for ,, , , , and genes were negative for SKI19. Also, SKI19 did not harbor any ,, or genes involved in biogenic amine production. The results reveal that SKI19 has probiotic potential and antibacterial activity, and is safe for further application in certain food products.

Probiotic Potential Lacticaseibacillus casei and Limosilactobacillus fermentum Strains Isolated from Dosa Batter Inhibit α-Glucosidase and α-Amylase Enzymes

“…The cell surface hydrophobicity of the isolates was tested according to the method described by Botthoulath et al (2018) [20] with slight modification. It helps us understand the interaction between xylene (polar solvent) and the bacteria.…”

Antagonistic lactic acid bacteria in association with Saccharomyces cerevisiae as starter cultures for standardization of sour cassava starch production

“…4 The diameter of starch hydrolysis halos (mm) and inhibition halos (mm) of Lactobacillus brevis isolates (Lb1-Lb12) against Bacillus cereus, Escherichia coli, and Salmonella Typhimurium by the spot-on-lawn method LAB, which can decrease the pH of the medium to values low enough to inhibit the growth of most pathogenic and deteriorating microorganisms. However, some authors report that some strains of L. plantarum can be bacteriocinogenic (Botthoulath et al 2018).…”

Characteristics of Beef Sausage Mixed with Modified Bekasam Meat Fermented by Lactobacillus plantarum

“…Costa et al (2013) reported that the addition of L. plantarum to bekasam meat produced a higher lactic acid that would inhibit the growth of E. coli and S. aureus. Similarly, Botthoulath et al (2018) found an inhibitory activity in fermented pork sausage against E. coli DMST 4212 and S. aureus DMST 8840, as the pathogen cell counts fell rapidly by approximately 3 log units at 24 h, and further to below detection limit after 36 h of incubation. The production of bekasam meat using grampositive lactic acid bacteria (L. plantarum) would produce a zone of inhibition to the growth of pathogenic bacteria (Gloria et al, 2012;Wang et al, 2018).…”