Enhanced Production of Bioactive Sophorolipids by Starmerella bombicola NRRL Y-17069 by Design of Experiment Approach with Successive Purification and Characterization

Abstract

INTRODUCTION Biosurfactants are potential surfactants obtained from natural sources and gives several advantages over chemically synthesized surfactants. They are less toxic in nature, biodegradable and environmentally acceptable 1) and hence attracted a great attention. SLs, surface-active glycolipids are one of the well-known members of biosurfactant family produced by microorganisms and extracellularly by Candida bombicola 2-5). These are amphiphilic in nature, i.e. containing both hydrophobic as well as hydrophilic moieties making them able to help in reduction of surface and interfacial tension at the surface and interface respectively 6). The physicochemical properties, such as decrease in interfacial tension, heat and pH stability of many biosurfactants have been shown to be comparable to synthetic surfactants 7). These biosurfactants are widely used in the food, pharmaceutical, cosmetic, and cleaning industries. Optimization of media component is one of the most important stages in production of any fermentative product. Single parameter study is time consuming and it will not explain the interactions between independent variables.

Production, characterization and anticancer activity of <em>Candida bombicola</em> sophorolipids by means of solid state fermentation of sunflower oil cake and soybean oil

“…All these structural details of the products were found similar to those reported by Yongmei and Lu-Kwang (2001); Daverey and Pakshiragan (2009) and Bajaj et al (2012), which confirmed that these products are SL compounds.…”

“…The presence of the-CO-CH 3 group in all structures was confirmed by the signals at 2.06 ppm in the spectra; on the other hand, the protons of two glucose were resonated at 3.4≈4.3 ppm in the Hexane fraction (E III). The signals obtained were similar to the one in the 1 H NMR spectrum of the SL compounds reported by other researchers (Wei et al, 2005;Chen et al, 2006a;Gao et al, 2007;Pakshiragan 2009 andBajaj et al, 2012).…”

Castor Oil as Secondary Carbon Source for Production of Sophorolipids Using <i>Starmerella bombicola</i> NRRL Y-17069

“…Substrates In all the previous sophorolipid studies 14,28 , hexane was used as solvent to remove unused residual oil. This study reveals that castor oil and sophorolipids both are insoluble in hexane.…”

“…The residue was further washed twice with hexane to remove the residual oil. The total yield of these partially purified SLs was measured by gravimetric measurement 14 The presence of ricinoleic fatty acids in sophorolipids was confirmed by GC analysis and results were compared with methyl ester of castor oil by GC. The samples were hydrolysed and esterified by adding 0.4 ml of 20 mM cupric acetate monohydrate in methanol and 2 ml of 0.5 N HCl in Hydranal.…”

“…Procedure of isolation for oleic acid was explained in detail by Bajaj et al, our last published paper 14 . In order to remove excess castor oil Hexane:chloroform 1:1 was used for 2-3 times , because castor oil is insoluble in hexane alone, differ to oleic acid removal.…”