Evaluation of the antimicrobial potential of indigenous probiotic strain
of Lactobacillus plantarum against skin pathogens Staphylococcus aureus
MTCC 96 and Propionibacterium acne MTCC 1950
In this comprehensive study, the antimicrobial activity of selected
probiotic L. plantarum isolates against prevalent skin pathogens
Staphylococcus aureus MTCC 96 and Propionibacterium acne MTCC 1950 were
evaluated. Our findings showcased a spectrum of antimicrobial efficacy
among these isolates, ranging from 10 mm ± 0.71 to 20 mm ± 0.58 against
S. aureus MTCC 96 and P. acne MTCC 1950. The study delved further into
the nature of antimicrobial agents by subdividing conditioned cell-free
supernatants (CFS) of L. plantarum isolates into three categories.
Results indicated that while 15 isolates were positive against S.
aureus, only two isolates (LpJ4 and LpJ5) maintained positivity with
conditioned CFS treatment. Similarly, although fourteen isolates
exhibited positive results against P. acne with non-conditioned CFS,
only three isolates (LpJ1, LpJ15, and LpJ19) demonstrated zone of
inhibition (>14mm) with conditioned CFS. These findings
emphasized the heightened antimicrobial activity of non-conditioned CFS
due to the presence of organic acids. Moreover, it suggested a potential
role of proteins in this antimicrobial activity, as demonstrated by the
loss of inhibitory effects following treatment with proteinase K.
Furthermore, our study explored the auto-aggregation and co-aggregation
capabilities of these probiotic isolates, indicating their potential to
adhere to gastrointestinal epithelial cells and facilitate microorganism
interactions. The understanding of these factors offers substantial
potential for the development of precise therapies aimed at addressing
skin infections attributed to these pathogens.