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Natural products have been recognized as a major source of new drugs,but it is difficult to obtain effective compounds or their reference substance from these complicate samples.Microwave-assisted extraction(MAE)is a simple and efficient technique for the extraction of analytes in complex samples,while high speed counter-current chromatography(HSCCC)is a unique liquid-liquid partition chromatography method with high recovery,high efficiency for the separation and purification of selected targets from natural products.In this work,an online strategy based on MAE coupled with HSCCC is designed for the direct preparation of effective targets in milligram level with high purity from original natural products.About fifty effective compounds were obtained from Chinese herbal medicines and marine botanicals with the online MAE-HSCCC strategy.1.Effective compounds from Chinese herbs.More than thirty furocoumarins,flavonoids and alkaloids were prepared using the online MAE-HSCCC strategy.Among them,six furocoumarins including xanthotoxin,bergapten,columbianetin acetate,osthole,isoimperatorin and columbianadin were obtained from A.Pubescentis within 450 min.All of their purities determined by HPLC were over 98%.Four flavonoids such as scutellarin(4.5 mg,94%),baicalin(4.6 mg,97%),luteolin(1.1 mg,98%),apigenin(2.1 mg,98%)were obtained from 2.0 g S.barbata.Moreover,five alkaloids including 5.7 mg sinomenine,8.3 mg 6,7-di-O-acetylsinococuline,17.9 mg berbamine,12.7 mg isotetrandrine and 14.6 mg cepharanthine were obtained from 6.0 g S.cepharantha with purities of 97%,94%,99%,97%and 99%,respectively.1.Effective compounds from marine botanicals.Effective compounds from marine botanicals were prepared by the online MAE-HSCCC strategy.About 13.0 mg fucosterol,1.5 mg 24-methylenecholesterol and 10.7 mg phytol were obtained within 220 min from 15.0 g U.pinnatifida.While 0.83 mg,1.09 mg,and 0.20 mg fucoxanthin were obtained within 75 min from 25.0 g fresh L.japonica,1.5 g dry U.pinnatifida,and 15.0 g dry S.fusiforme,respectively.The purities of all products were over 90%.These results showed that the online MAE-HSCCC strategy is feasible and efficient for the extraction,separation and purification of effective compounds from natural products.