Rhamnolipids from Planococcus spp. and their mechanism of action against pathogenic bacteria. (July 2020)

• Record Type: Journal Article
• Authors: Gaur, Vivek Kumar; Tripathi, Varsha; Gupta, Pallavi; Dhiman, Nitesh; Regar, Raj Kumar; Gautam, Krishna; Srivastava, Janmejai Kumar; Patnaik, Satyakam; Patel, Devendra Kumar; Manickam, Natesan
• Is Part Of: Bioresource technology. Volume 307(2020)
• Publication Date: 2020-07
• Subjects: Planococcus sp. -- Rhamnolipid -- Vegetable oil -- Bactericidal -- Biosurfactant; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2020.123206
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Planococcus spp. produced rhamnolipid biosurfactant. Emulsification activity was retained under extreme temperature, salinity and pH. Rhamnolipid effectively emulsify different vegetable oils. Isolated rhamnolipid exhibited bactericidal activity against pathogenic bacteria. Rhamnolipid exhibit killing by interacting with bacterial cell membrane. Abstract: Two bacterial species with the ability to produce biosurfactants were isolated from a pesticide contaminated soil and identified as Planococcus rifietoensis IITR53 and Planococcus halotolerans IITR55. Formation of froth indicating the surfactant production was observed when grown in basal salt medium containing 2% glucose. The culture supernatant after 72 h showed reduction in surface tension from 72 N/m to 46 and 42 N/m for strain IITR53 and IITR55 with emulsification index of 51 and 54% respectively. The biosurfactant identified as rhamnolipid based on liquid chromatography–mass spectrometry analysis, was found to inhibit the growth of both gram- positive and negative pathogenic bacteria. Both the rhamnolipids at 40 mg/mL exhibited the release of extracellular DNA and protein content. Also at one third of the MIC, a significant generation of reactive oxygen species was recorded. These rhamnolipids effectively emulsified different vegetable oils suggesting their possible utilization as antimicrobial agent.