title: Extraction and characterization of polysaccharides from Semen Cassiae by microwave-assisted aqueous two-phase extraction coupled with spectroscopy and HPLC.
abstract: A novel and rapid method for simultaneous extraction and separation of the different polysaccharides from Semen Cassiae (SC) was developed by microwave-assisted aqueous two-phase extraction (MAATPE) in a one-step procedure. Using ethanol/ammonium sulfate system as a multiphase solvent, the effects of MAATPE on the extraction of polysaccharides from SC such as the composition of the ATPS, extraction time, temperature and solvent-to-material ratio were investigated by UV-vis analysis. Under the optimum conditions, the yields of polysaccharides were 4.49% for the top phase, 8.80% for the bottom phase and 13.29% for total polysaccharides, respectively. Compared with heating solvent extraction and ultrasonic assisted extraction, MAATPE exhibited the higher extraction yields in shorter time. Fourier-transform infrared spectra showed that two polysaccharides extracted from SC to the top and bottom phases by MAATPE were different from each other in their chemical structures. Through acid hydrolysis and PMP derivatization prior to HPLC, analytical results by indicated that a polysaccharide of the top phases was a relatively homogeneous homepolysaccharide composed of dominant gucose glucose while that of the bottom phase was a water-soluble heteropolysaccharide with multiple components of glucose, xylose, arabinose, galactose, mannose and glucuronic acid. Molar ratios of monosaccharides were 95.13:4.27:0.60 of glucose: arabinose: galactose for the polysaccharide from the top phase and 62.96:14.07:6.67: 6.67:5.19:4.44 of glucose: xylose: arabinose: galactose: mannose: glucuronic acid for that from the bottom phase, respectively. The mechanism for MAATPE process was also discussed in detail. MAATPE with the aid of microwave and the selectivity of the ATPS not only improved yields of the extraction, but also obtained a variety of polysaccharides. Hence, it was proved as a green, efficient and promising alternative to simultaneous extraction of polysaccharides from SC.
authors.affiliation: School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Chen
authors.affiliation: School of Basic Courses, Guangdong Pharmaceutical University, Guangzhou 510006, China. Electronic address: gzzhangw@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, China.
authors.forename: Xunyou
authors.initials: X
authors.lastname: Tang
authors.affiliation: School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, China; School of Pharmacy, Faculty of Science and Engineering, University of Wolverhampton, Wolverhampton, WV1 1LY, United Kingdom. Electronic address: junhuafan@126.com.
authors.forename: Huajun
authors.initials: H
authors.lastname: Fan
authors.affiliation: School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, China.
authors.forename: Xiujuan
authors.initials: X
authors.lastname: Xie
authors.affiliation: School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wan
authors.affiliation: School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, China.
authors.forename: Xuehao
authors.initials: X
authors.lastname: Wu
authors.affiliation: School of Pharmacy, Faculty of Science and Engineering, University of Wolverhampton, Wolverhampton, WV1 1LY, United Kingdom.
authors.forename: James Z
authors.initials: JZ
authors.lastname: Tang
mesh_terms: D000983:Antipyrine / Q000031:analogs & derivatives / Q000737:chemistry; D002366:Cassia / Q000737:chemistry*; D005591:Chemical Fractionation / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D000077553:Edaravone; D008872:Microwaves; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification*; D012997:Solvents / Q000737:chemistry; D013057:Spectrum Analysis; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry*
chemical_list: D011134:Polysaccharides; D012997:Solvents; D014867:Water; D000077553:Edaravone; D000983:Antipyrine
keywords: Characterization; HPLC; Microwave-assisted aqueous two-phase extraction; Polysaccharide; Semen Cassiae; Spectroscopy