Vortex fluidic-mediated transesterification enhancement of mongongo fatty acid ethyl ester production for haircare applications†

Abstract

Fatty acid ethyl esters (FAEE) are one of the most popular ingredients in the organic cosmetic market due to their versatile functionality. However, its production technique aligning with the principle of green chemistry and adhering to organic standards remains unexplored. This study investigated the use of the vortex fluidic device (VFD), a versatile thin-film processing device that can generate substantial mechanical energy within a rapidly rotating tube, to assist in the sustainable and efficient production of Mongongo FAEE. Using the VFD, a FAEE yield of 92.65% was achieved within 20 minutes of processing, 1.3 times more effective than that attained via bench-top methods. Proton nuclear magnetic resonance (¹H NMR) and gas chromatography-mass spectrometry (GC-MS) confirmed the preservation and elevated concentrations of polyunsaturated FAEE following VFD processing. Furthermore, Mongongo FAEE was investigated for its application in hair protection. In a custom hair styling simulation experiment, a comparative analysis of Mongongo oil with FAEE demonstrated that Mongongo FAEE exhibited superior coverage efficiency on the hair surface, masking 95% of sulphur and nitrogen from the hair surface. This results in reduction in pore size, improved surface integrity, enhanced gloss, and minimised cysteine oxidation of hair. In the sun protection test, the FAEE-treated hair demonstrates a uniform morphology after 8 hours of sunlight exposure. Overall, it has been shown that a high yield of Mongongo FAEE was effectively achieved via VFD processing, while also demonstrating the ability to use the product in haircare applications.