The prevalence of antimicrobial-producing Gram-positive bacteria in human gut: a preliminary study

B ackground: Human gut microbiome is an excellent source for searching novel antimicrobials which is currently in need due to the raise of drug resistance bacteria. Many Gram-positive bacteria isolated from human gut have been reported to produce antimicrobial compounds but still only few studies investigating the prevalence of these bacteria in human gut. Methods: We took stool samples from 19 adult participants (age: 20–70 years; ethnicity: European and Asian). Stool samples obtained from 7 females and 12 males. We screened for Gram-positive antimicrobial-producing bacteria from the stool samples and identified the positive ones using 16s rRNA sequencing. Results: Here, we reported that antimicrobial-producing Gram-positive bacteria can be found in the stool samples of 6 out of 19 participants. By screening against Staphylococcus aureus USA300 and Pseudomonas aeruginosa PAO1, some isolates exhibited a different inhibition activity compared to the previously reported antimicrobial compounds. Conclusion: Our findings showed that some strains isolated from human gut exhibits a novel antimicrobial activity which implies that there could still be novel antimicrobial compounds in human gut produced by Gram-positive bacteria.