Extraction of hydroxycinnamic acids (ferulic and p-coumaric) from rice straw alkaline black liquor using Pluronic F-127 for potential applications in the cosmetics industry

Abstract

In the present study, ferulic (FA) and p-coumaric (pCA) acids were extracted from rice straw (Oryza sativa) alkaline black liquor by an aqueous two-phase system (ATPS) based on cloud point of surfactant/copolymer Pluronic F-127 (PF-127). An acid precipitation process was studied as a primary purification step of FA and pCA and next, an extraction of these hydroxycinnamic acids (HAs) using PF-127 in different concentrations (1.1–17.3% w/w) was performed. The results showed that in PF-127 concentration of 9.4% w/w, yield extractions of 75.8% for FA and 74.3% for pCA were achieved. In addition, FA and pCA were concentrated 2.3 and 2.5-fold, respectively, compared to their original concentrations in the liquor, resulting in a PF-127 gel containing 0.12% w/w HAs. This material will be further investigated for potential applications in the cosmetics industry as an alternative for obtaining high value-added products in a rice straw-based biorefinery. Data availabilityData will be made available on request.