Antifungal Activity of Rhamnolipid Biosurfactant Produced by Pseudomonas aeruginosa A4 against Plant Pathogenic Fungi

Biosurfactants have been shown to a variety of other agricultural applications. Antimicrobial activity is desirable property in biosurfactants. Several biosurfactants produced from bacteria antibacterial against plant diseases, making them promising biocontrol molecule for ensuring sustainability the long run. The purpose this research was characterize biosurfactant at different carbon source by biosurfactant-producing bacterial strains isolated contaminated soapstock sediment, as well its antifungal properties. Biosurfactant-producing were soapstock-contaminated soil which selected using drop collapse and oil displacement tests. Twelve isolates reduced surface tension culture broth 50 31 - 43 mN/m. According 16S rRNA sequence analysis, these belong 8 genera (Acinetobacter, Citrobacter, Enterobacter, Klebsiella, Pantoea, Pseudomonas, Stenotrophomonas Xanthomonas). supernatant Pseudomonas aeruginosa A4 grown MSM supplemented with most effective Aspergillus flavus F2, niger F14, Cunninghamella bertholletiae F1 Rhizopus oryzae F5, inhibiting mycelium growth 54, 61 59 %, respectively. extract substance inhibited spore germination A. F2 R. F5 minimum inhibitory concentration 2.75 mg/mL. TLC, FT-IR, ESI-MS GC-MS analysis demonstrated that mono-rhamnolipids di-rhamnolipids had same 3-hydroxy fatty acid composition C8, C10 C12. Overall, identified investigation show promise future development application cost-effective industrial-scale biotechnological processes.
 HIGHLIGHTS
 
 Biosurfactant producing soil
 pathogenic fungi
 rhamnolipid comprising both mono di-rhamnolipid congeners
 GRAPHICAL ABSTRACT