title: Optimization of Ultrasound-Assisted Extraction of Natural Antioxidants from the Flower of Jatropha integerrima by Response Surface Methodology.
abstract: An ultrasound-assisted extraction (UAE) method was developed for the efficient extraction of natural antioxidants from the flowers of Jatropha integerrima. Four independent variables, including ethanol concentration, solvent/material ratio, ultrasound irradiation time and temperature were studied by single factor experiments. Then, the central composite rotatable design and response surface methodology were employed to investigate the effect of three key parameters (ethanol concentration, solvent/material ratio, and ultrasound irradiation time) on the antioxidant activities of the flower extracts. The optimal extraction conditions were an ethanol concentration of 59.6%, solvent/material ratio of 50:1, ultrasound irradiation time of 7 min, and ultrasound irradiation temperature of 40 °C. Under these conditions, the optimized experimental value was 1103.38 ± 16.11 µmol Trolox/g dry weight (DW), which was in accordance with the predicted value (1105.49 µmol Trolox/g DW). Furthermore, the antioxidant activities of flower extracts obtained by UAE were compared with those produced by the traditional maceration and Soxhlet extraction methods, and UAE resulted in higher antioxidant activities after a shorter time at a lower temperature. The results obtained are helpful for the full utilization of Jatropha integerrima, and also indicate that ultrasound-assisted extraction is an efficient method for the extraction of natural antioxidants from plant materials.
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. zhouyue3@mail2.sysu.edu.cn.
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China. zhengj37@mail2.sysu.edu.cn.
authors.forename: Jie
authors.initials: J
authors.lastname: Zheng
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. lianna28@163.com.
authors.forename: An-Na
authors.initials: AN
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. lihuabin@mail.sysu.edu.cn.
authors.forename: Hua-Bin
authors.initials: HB
authors.lastname: Li
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000431:Ethanol / Q000737:chemistry; D035264:Flowers / Q000737:chemistry*; D031286:Jatropha / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D013696:Temperature; D000069453:Ultrasonic Waves
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D000431:Ethanol
keywords: Jatropha integerrima; flower; natural antioxidant; response surface methodology; ultrasound-assisted extraction