Optimizing The Protocol For Extraction Of Bioactive Components From Hibiscus Sabdariffa With Potent Antioxidant Activity

Abstract

The extract of Hibiscus sabdariffa (HS) also known as roselle from the Malvaceae family is prized for its exceptionally high contents of polyphenols and anthocyanins, the calyces of HS being one of the many sources of natural antioxidants. Considering the numerous health benefits associated with the consumption of such compounds as well its broad application in the food industry, the development of an extraction protocol for such compounds from HS at high yields and antioxidant activity merits scientific relevance. In this study, the optimum conditions to achieve such goals were established by the method of response surface methodology (RSM) using three independent variables: time (30, 165, and 300 min), temperature (50, 70, and 90°C) and ethanol concentration (60, 75 and 90%). A Box-Behnken design (BBD) was utilized to determine the optimum condition that yielded the highest extraction yield and antioxidant activity measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical inhibition activity test. The results showed that under optimum conditions [300 min, 70°C in 90% ethanol concentration and 30 min, 70°C in 90% ethanol concentration], a corresponding 48.44% and 87.93% were obtained for the extraction yield and DPPH activity of HS, respectively; hence verifying the suitability of RSM for optimizing the extraction of HS.