Selection Of An Antifungal Bacillus niabensis From Algerian Salt Soil And Study Of Its Potential Of Surfactin Production

Abstract

Bacillus niabensis CWBI-B1569 (accession number KC341750) was isolated from salt soil of two different saline regions of Algeria and screened for its production of bioactive compounds. Both the antagonistic and cell-free culture supernatant of strain CWBI-B1569 showed strong in vitro growth inhibition activity against Aspergillus repens, Candida albicans, C. tropicalis and Yarrowia lipolytica. Bioactive molecules were produced by B. niabensis CWBI-B1569 in a liquid culture medium optimised for lipopeptide production. Inhibition of fungi was equally demonstrated by testing the resulting supernatant and Lipopeptide-enriched extracts. The association of mass spectrometry and liquid chromatography (LC-MS) analysis revealed the presence of compounds which were similar to the lipopeptide Surfactin. Surfactin purified from Bacillus niabensis CWBI-B1569 had three homologous, C14, C15 and C16, with protonated masses of m/z 1044.7, 1058.7, and 1072.7, respectively. Thus, B. niabensis CWBI-B1569 may play an important role in biological control, and should be added to the list of Bacillus species, as one of the largest sources of bioactive natural products