A class of surfactants via PEG modification of the oleate moiety of lactonic sophorolipids: synthesis, characterisation and application

Joseph K Ogunjobi,David Thornthwaite,Con R Mcelroy,Thomas J Farmer,Osaretin E Omoruyi,James H Clark

doi:10.1039/d1gc02247d

Abstract

A family of new bio-based surfactants have been prepared via the epoxidation and PEGylation of lactonic sophorolipids. This modification enhances their performance and diversifying their potential applications.

Highlights

Sophorolipids (SLs) are a class of non-ionic glycolipid bio-surfactants first reported in 1961.1 They are synthesised by nonpathogenic yeasts such as Candida gropengiesseri,[2] Candida apicola,[3] Rhodotorula bogoriensis and Rhodotorula babjavae YS34 but the most widely used organism for the synthesis of SLs has been Starmerella bombicola.[5]
Complete LSL conversion was achieved under 3 hours with 99.2% selectivity and >99% mass recovery of the epoxidised lactonic sophorolipid (ELSL), as a hygroscopic solid
Some residual Adogen 464 phase transfer catalyst was detected in the ELSL and proved inseparable

Summary

Introduction

Sophorolipids (SLs) are a class of non-ionic glycolipid bio-surfactants first reported in 1961.1 They are synthesised by nonpathogenic yeasts such as Candida gropengiesseri,[2] Candida apicola,[3] Rhodotorula bogoriensis and Rhodotorula babjavae YS34 but the most widely used organism for the synthesis of SLs has been Starmerella bombicola.[5]. Scheme 1 Modifications on the double bond of sophorolipid’s fatty acid[24,26,28,29,30] and synthesis of lactonic sophorolipid epoxide (ELSL) from lactonic sophorolipids (LSL) and subsequent modification to PEGylated surfactants (this study).

Results

Conclusion