Main Article Content

Optimization of extraction of polyphenols from Sorghum Moench using response surface methodology, and determination of their antioxidant activities


Liu Liu
Long Chen
Arshad Mehmood Abbasi
Zichao Wang
Dianxin Li
Yingbin Shen

Abstract

Purpose: To employ response surface methodology (RSM) hinged on a central composite design (CCD) for the optimization of the extraction of polyphenols from Sorghum moench (Sorghum M).
Methods: The combined influence of independent variables were assessed with RSM. Total phenolic content (TPC) determination was carried out using Folin-Ciocalteu method. Derivative compounds of phenolic acid were assayed using high performance liquid (HPLC). Antioxidant potential was determined through 1,1-diphenyl-2- picrylhydrazyl (DPPH) radical scavenging test.
Results: The optimized extraction conditions were: 60.37 % ethanol, temperature of 59.07 oC and 2.97 h of extraction duration, which resulted in the extraction of maximum amount of TPC, i.e., 313 mg GAE/100g dry weight. The interactions between temperature and ethanol concentration, and between extraction time and ethanol concentration had significant effects of TPC (p < 0.05). Under these conditions, there was a consistency between the projected and actual experimental levels of polyphenols. A positive correlation was found between TPC and DPPH radical scavenging activity (r=0.67, p <0.05). Furthermore, ferulic acid correlated positively with p-coumaric acid (r = 0.54, p <0.01).
Conclusion: These results underscore the usefulness of conditions for extraction in accurate
quantification of antioxidants and phenolic compounds from Sorghum M, for possible application in large scale commercial extraction.

Keywords: Response surface methodology, Sorghum moench, Polyphenols, Antioxidants


Journal Identifiers


eISSN: 1596-9827
print ISSN: 1596-5996