Green Synthesis of Polyglycerol Ester Surfactants and Application in Personal Care Formulations

ABSTRACT Polyglycerol esters (PGEs) are non‐ionic surfactants which have a wide range of applications in industries like cosmetics, foods, textiles, pharmaceuticals, etc. These are generally synthesized using alkaline catalysts under stringent conditions such as high temperature and pressure, which may lead to the degradation of the polyglycerol molecule. Due to demand for surfactants from renewable resources, PGEs are synthesized through a green‐lipase catalyzed process using green catalysts. This reaction offers mild operating conditions with high selectivity and minimal by‐product formation, making them suitable for commercialization. In the present study, PGEs were synthesized by reacting fatty material obtained from waste cooking oil (WCO) and acid oil (AO) with tri‐glycerol using Novozyme 435 as an enzymatic catalyst. The esterification process was optimized and monitored through acid value reduction and efficiency calculation, yielding the highest esterification efficiency of 75.28% for PGEs. Surfactant performance was evaluated through surface tension, critical micelle concentration (CMC), contact angle, foaming ability, emulsification index, and antibacterial activity. The synthesized PGEs displayed superior surface activity, such as surface tension (27.24 mN/m), critical micelle concentration (0.022 mM), and foaming as well as good anti‐microbial properties.