Studies on biosurfactants from Pseudozyma sp. NII 08165 and their potential application as laundry detergent additives

Abstract

The novel isolate Pseudozyma sp. NII 08165 produced glycolipid biosurfactants, which was a combination of all the three mannosylerythritol lipids (MELs) isomers along with some unknown glycolipids. The strain produced 34 g/l MELs in medium containing 8% (w/v) soybean oil as carbon source after nine days of fermentation. The structural characterization of purified MEL revealed the hydrophobic structure of MEL-C consisting of short chain fatty acid (C2 or C4) at the C-2 position and a long chain fatty acid (C14, C16 or C18) at the C-3 position of the mannose moiety. The MEL-C showed good surface activity with critical micelle concentration (CMC) of 4.5×10−6M and surface tension of 33 mN/m at CMC. The crude biosurfactants were stable at high temperature and over the alkaline pH range which favour their scope of application as laundry detergent additives. Fabric wash analysis revealed that crude biosurfactants from Pseudozyma sp. NII 08165 removed stains efficiently and can be used in laundry detergent formulations.