The use of a microwave-assisted extraction (MAE) method for the extraction ofphlorotannins from Saccharinajaponica Aresch (S.japonica) has been evaluated with particular emphasis on the influential parameters, inc...The use of a microwave-assisted extraction (MAE) method for the extraction ofphlorotannins from Saccharinajaponica Aresch (S.japonica) has been evaluated with particular emphasis on the influential parameters, including the ethanol concentration, solid/liquid ratio, extraction time, extraction temperature, and microwave power. The MAE procedure was optimized using single-factor design and orthogonal array design (OAD). The content of total phlorotannins in S. japonica was determined using a Folin-Ciocalteu (FC) assay. A maximum total phlorotannin content of 0.644 mg of phloroglucinol equivalent per gram of dry weight plant (mg PGE/g DW) was obtained using the optimized model, which included an ethanol concentration of 55%, solid/liquid ratio of 1:8, extraction time of 25 min, irradiation power of 400 W, and temperature of 60~C. Under similar conditions, the application of a conventional extraction method led to a lower phlorotarmin yield of 0.585 mg PGE/g WD. These results demonstrated that the MAE approach provided better results for the extraction ofphlorotarmins from S.japonica and was a promising technique for the extraction of phenolic compounds from S. japonica and other materials. In addition, screening tests for the inhibitory activity showed that the phlorotannin-containing extracts significantly inhibited the growth of human hepatocellular carcinoma cells (HepG2) by inducing their apoptosis. The morphological changes that occurred during cell apoptosis were characterized using Hoechst33258 staining.展开更多
基金Supported by the National Natural Science Foundation of China(No.51203028)Rural Science and Technology Correspondent and Technology Service System Construction Projects,Guangdong Province(No.2010A020507001-91)Science and Technology Project of Panyu District,Guangzhou City(No.2010-12-08)
文摘The use of a microwave-assisted extraction (MAE) method for the extraction ofphlorotannins from Saccharinajaponica Aresch (S.japonica) has been evaluated with particular emphasis on the influential parameters, including the ethanol concentration, solid/liquid ratio, extraction time, extraction temperature, and microwave power. The MAE procedure was optimized using single-factor design and orthogonal array design (OAD). The content of total phlorotannins in S. japonica was determined using a Folin-Ciocalteu (FC) assay. A maximum total phlorotannin content of 0.644 mg of phloroglucinol equivalent per gram of dry weight plant (mg PGE/g DW) was obtained using the optimized model, which included an ethanol concentration of 55%, solid/liquid ratio of 1:8, extraction time of 25 min, irradiation power of 400 W, and temperature of 60~C. Under similar conditions, the application of a conventional extraction method led to a lower phlorotarmin yield of 0.585 mg PGE/g WD. These results demonstrated that the MAE approach provided better results for the extraction ofphlorotarmins from S.japonica and was a promising technique for the extraction of phenolic compounds from S. japonica and other materials. In addition, screening tests for the inhibitory activity showed that the phlorotannin-containing extracts significantly inhibited the growth of human hepatocellular carcinoma cells (HepG2) by inducing their apoptosis. The morphological changes that occurred during cell apoptosis were characterized using Hoechst33258 staining.