Experimental Design Assisted Different Extraction Methods for Study Antioxidant in Crossostephium chinense (L.) Makino

• Main Authors: Chiang, Chiamei, 江佳玫
• Other Authors: Tsai, Fengjie
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/46244010632434844116

碩士 === 靜宜大學 === 化粧品科學系 === 101 === In this study, L9 (34) orthogonal experimental design method and statistical analysis were used to investigate optimum conditions of fresh and dried Crossostephium chinense (L.) Makino leaves for ultrasonic-assisted extraction, microwave-assisted extraction and immersion extraction. These methods are four factors and three levels were investigated. DPPH radical scavenging efficiency was the evaluation criteria. Main factor effect, factor-to-factor interaction and two curvature effects were included in the analysis second-order polynomial model significant additive effects by multiple regression analysis. The optimal conditions for fresh leaves, by ultrasonic-assisted extraction were using 2-propanol as extraction solvent, solvent-to-solid ratio 10:1, extraction temperature 25 oC and extraction time 15 min. By microwave-assisted extraction was ethanol as extraction solvent, solvent-to-solid ratio 10:1, extraction power 455 ω and extraction time 30 sec. By the immersion extraction was 2-propanol as xtraction solvent, solvent-to-solid ratio 6:1, extraction temperature 60 oC and extraction time 4 hr. The optimal conditions for dried leaves, by ultrasound-assisted extraction was using ethanol as extraction solvent, solvent-to-solid ratio 10:1, the extraction power of 60 oC and extraction time 45 min. By microwave-assisted extraction was ethanol as extraction solvent, solvent-to-solid ratio 10:1, extraction power 455 ω and extraction time 60 sec. By immersion extraction was ethanol as extraction solvent, solvent-to-solid ratio 8:1, extraction temperature 60 oC and extraction time 12 hr. The results of the DPPH radical scavenging ability showed that microwave-assisted extraction method was the best extraction method of three both in extracted fresh and dry leaves at 1 mg/mL. The antioxidant efficiency did not show significant difference between from fresh and dried leaves extracts by microwave-assisted extraction method. There are exited significant seasonal effects from fresh extracts by three methods. Excluding microwave-assisted extract, other two methods showed significant seasonal effects from dried leaves. In generally, the leaves from early summer have higher antioxidant ability than early winter.