title: Ultrasonic-assisted extraction and in-vitro antioxidant activity of polysaccharide from Hibiscus leaf.
abstract: The effects of ultrasonic power, extraction time, extraction temperature, and the water-to-raw material ratio on extraction yield of crude polysaccharide from the leaf of Hibiscus rosa-sinensis (HRLP) were optimized by statistical analysis using response surface methodology. The response surface methodology (RSM) was used to optimize HRLP extraction yield by implementing the Box-Behnken design (BBD). The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis and also analyzed by appropriate statistical methods (ANOVA). Analysis of the results showed that the linear and quadratic terms of these four variables had significant effects. The optimal conditions for the highest extraction yield of HRLP were: ultrasonic power, 93.59 W; extraction time, 25.71 min; extraction temperature, 93.18°C; and the water to raw material ratio, 24.3 mL/g. Under these conditions, the experimental yield was 9.66±0.18%, which is well in close agreement with the value predicted by the model 9.526%. The results demonstrated that HRLP had strong scavenging activities in vitro on DPPH and hydroxyl radicals.
authors.affiliation: Department of Food Science and Technology, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran. Electronic address: kasraaf2005@yahoo.com.
authors.forename: Kasra
authors.initials: K
authors.lastname: Afshari
authors.affiliation: Department of Food Science and Technology, Ramin Agricultural and Natural Resources University, Ahvaz, Iran. Electronic address: vsamavati@ut.ac.ir.
authors.forename: Vahid
authors.initials: V
authors.lastname: Samavati
authors.affiliation: Assistant Professor, Department of Food Science and Technology, College of Agriculture and Food Science, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran.
authors.forename: Seyed-Ahmad
authors.initials: SA
authors.lastname: Shahidi
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D005591:Chemical Fractionation / Q000379:methods*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D031584:Hibiscus / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D012997:Solvents
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D010936:Plant Extracts; D011134:Polysaccharides; D012997:Solvents
keywords: Extraction; Hibiscus rosa-sinensis leaf; Polysaccharide; Response surface methodology.; Ultrasound