Microwave Multi-Stage Countercurrent Extraction of Dihydromyricetin from Ampelopsis grossedentata

Wei Li^1,2, Cheng Zheng³*, Jinshui Wang⁴, Youyuan Shao¹, Yanxiang Gao², Zhengxiang Ning⁴ and Yueming Jiang<sup>5

1</sup>College of Biological Engineering, Hubei University of Technology, Wuhan 430068, PR China
²College of Food Science and Nutritional Engineering, China Agriculture University, Beijing 100083, PR China
³College of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510091, PR China
⁴College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640, PR China
⁵South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China

Article history:
Received November 30, 2005
Accepted December 4, 2006

Key words:
microwave-assisted extraction, microwave multi-stage countercurrent extraction, dihydromyricetin, Ampelopsis grossedentata, extraction efficiency

Summary:
Microwave-assisted extraction (MAE) technique in combination with multi-stage countercurrent extraction (MCE), namely microwave multi-stage countercurrent extraction (MMCE), was evaluated for the extraction of dihydromyricetin (DMY) from Ampelopsis grossedentata. Ethanol, methanol and water were used as extract solvents in the MMCE method. Of the three solvents used, water was found to be the best in extracting DMY from Ampelopsis grossedentata because it had a good extraction yield and is inexpensive, non-toxic and environmentally friendly. The optimal conditions of MMCE for the extraction of DMY can be determined to be the ratio of the extraction solvent to plant material of 30:1, the extraction time of 5 min, the extraction temperature of 110 °C and the microwave power of 600 W. In addition, the extraction efficiency of the MMCE method was compared with that of the microwave static batch extraction (MSBE) under the optimum extraction conditions. It was found that the MMCE method offered higher extraction efficiency than the MSBE method. Thus, the study suggests that the MMCE method provides an alternative technique in terms of both cost and efficiency.

*Corresponding author:           liweimx118@163.com, zhcheng123@tom.com
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