title: Optimization of Ultrasound-Assisted Extraction of Natural Antioxidants from the Osmanthus fragrans Flower.
abstract: An ultrasound-assisted extraction (UAE) method was developed to extract natural antioxidants from the Osmanthus fragrans flower. The effect of UAE on antioxidant activity of the extract from the Osmanthus fragrans flower was studied using a Trolox equivalent antioxidant capacity (TEAC) assay. Optimization conditions were firstly determined using a single-factor experiment, and response surface methodology was then used to evaluate interaction of several experimental parameters. Analysis of the coefficient of determination showed that second-order polynomial models produced a highly satisfactory fitting of the experimental data with regard to TEAC values (R² = 0.9829, p < 0.0001). The optimal conditions were 39.1% ethanol, and extraction for 35.2 min at 59.4 °C. Under these conditions, the maximum TEAC value was 584.9 ± 6.0 μmol Trolox/g DW, which was higher than those obtained by the conventional extracting method (486.4 ± 12.6 μmol Trolox/g DW) and the Soxhlet extraction method (339.1 ± 16.2 μmol Trolox/g DW). The crude extract obtained could be used either as a food additive or in pharmaceuticals for the prevention and treatment of diseases caused by oxidative stress.
authors.affiliation: Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China. lianna28@163.com.
authors.forename: An-Na
authors.initials: AN
authors.lastname: Li
authors.affiliation: School of Chinese Medicine, The University of Hong Kong, Hong Kong, China. lishasl0308@163.com.
authors.forename: Sha
authors.initials: S
authors.lastname: Li
authors.affiliation: Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China. saferide@126.com.
authors.forename: Ya
authors.initials: Y
authors.lastname: Li
authors.affiliation: Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China. xudongping1989@163.com.
authors.forename: Dong-Ping
authors.initials: DP
authors.lastname: Xu
authors.affiliation: Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China. lihuabin@mail.sysu.edu.cn.
authors.forename: Hua-Bin
authors.initials: HB
authors.lastname: Li
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification*; D035264:Flowers / Q000737:chemistry; D005503:Food Additives / Q000302:isolation & purification; D029592:Oleaceae / Q000737:chemistry*; D010936:Plant Extracts / Q000032:analysis* / Q000737:chemistry; D014465:Ultrasonics / Q000379:methods
chemical_list: D000975:Antioxidants; D005503:Food Additives; D010936:Plant Extracts
keywords: Osmanthus fragrans; antioxidant; flower; response surface methodology; ultrasound-assisted extraction