In vitro Studies on Antagonistic Behaviour of Biosurfactant Producing Microorganism against Pathogenic Fungi Aspergillus niger and Aspergillus fumigatus

Abstract

ABSTRACT: Biosurfactant producing microorganisms have a potential in mitigating environmental pollution contaminated with hydrocarbon. This study aimed to isolate biosurfactant-producing organisms from the soil contaminated with oil. Out of the eight isolates, six (P1, P2, P3, D1, X, and Y) produced biosurfactant, as confirmed by the oil displacement method, with isolate P3 showing 4.2 cm oil displacement activity. The emulsification assay revealed that samples P3 and X had the highest emulsification activity at 25%. The identification of biosurfactant was further confirmed by the foaming activity method and biosurfactant extraction with chloroform and methanol. The biosurfactant nature was determined by the presence of glycolipid or neutral lipid, with the Rf values calculated for each isolate, and P3 showing a value of 0.92. Besides biosurfactant production, samples X, Y, and D1 also exhibited biocontrol activity against Aspergillus niger and Aspergillus fumigatus, as confirmed by fungal growth inhibition percentage and electron micrographic studies. This suggests the potential application of these isolates in bioremediation and biocontrol of plant pathogens. Further identification can be confirmed through 16s rRNA sequencing.