Lubricant Properties of ω − 1 Hydroxy Branched Fatty Acid-Containing Natural and Synthetic Lipids

Abstract

Hydroxy fatty acids, such as those derived from castor and lesquerella seed oils, make ideal substrates for the synthesis of bio-lubricants, cosmetics, coatings, plastics, and lubricant additives. However, feedstocks of such fatty acids suffer from major drawbacks, such as a lack of a cropping system to produce those seeds or toxic by-products in generating the seed oil, all of which limit availability and thus add to costs. In this study, we explore lubrication properties of microbially derived hydroxy fatty acids and demonstrate that such microbial ω − 1 hydroxy fatty acids, and their derivatives, exhibit lubrication traits (e.g., anti-friction and anti-wear properties) comparable to those of seed-derived hydroxy fatty acids. These ω − 1 hydroxy fatty acids can be recovered from sophorolipids produced by the yeast Candida bombicola ATCC 22214, or by bioengineering bacterial systems to produce them from sugar (Garg et al. in Metab Eng 35:9–20, 2016). Optimization of this latter system can pave the way for a less costly and sustainable alternative to plant-derived bio-lubricants.