title: Effect of calcium on solution and conformational characteristics of polysaccharide from seeds of Plantago asiatica L.
abstract: Polysaccharide from seeds of Plantago asiatica L. is rich in calcium, which is important for keeping viscous and weak gelling properties of the polysaccharide. However, few studies reported effect of calcium on solution and conformational characteristics of the polysaccharide. In this study, polysaccharide was prepared from seeds of P. asiatica L. and named as PLCP. PLCP was treated with EDTA to remove calcium ion to get PLCP-E. PLCP and PLCP-E were characterized by Ubbelohde capillary viscometer, light scattering and HPSEC with refractive index, light scattering and viscometric detectors. The results showed that PLCP had much higher intrinsic viscosity, hydrodynamic radius (Rh), radius of gyration (Rg) and molecular weight than that of PLCP-E when measured in the same solvent. PLCP and PLCP-E were in random coil conformation in aqueous solutions according to light scattering and HPSEC measurements. HPSEC data showed PLCP-E had lower intrinsic viscosity than that of PLCP with the same molecular weight. Persistence length of Lp was 2.5nm for PLCP and 2.3nm for PLCP-E, respectively. In conclusion, PLCP exhibited higher intrinsic viscosity and molecular weight, and stiffer conformation than that of PLCP-E, which could explain the reason of higher viscosity of PLCP.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Jun-Yi
authors.initials: JY
authors.lastname: Yin
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China. Electronic address: nie68@sina.com.
authors.forename: Shao-Ping
authors.initials: SP
authors.lastname: Nie
authors.affiliation: Guelph Food Research Centre, Agriculture and Agri-Food Canada, Guelph, Ontario N1G 5C9, Canada.
authors.forename: Qing-Bin
authors.initials: QB
authors.lastname: Guo
authors.affiliation: Guelph Food Research Centre, Agriculture and Agri-Food Canada, Guelph, Ontario N1G 5C9, Canada.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Guelph Food Research Centre, Agriculture and Agri-Food Canada, Guelph, Ontario N1G 5C9, Canada.
authors.forename: Steve W
authors.initials: SW
authors.lastname: Cui
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Ming-Yong
authors.initials: MY
authors.lastname: Xie
mesh_terms: D002118:Calcium / Q000737:chemistry*; D002850:Chromatography, Gel; D008027:Light; D008970:Molecular Weight; D010943:Plantago / Q000737:chemistry* / Q000378:metabolism; D011134:Polysaccharides / Q000737:chemistry*; D012031:Refractometry; D012542:Scattering, Radiation; D012639:Seeds / Q000737:chemistry / Q000378:metabolism; D012996:Solutions / Q000737:chemistry; D014783:Viscosity
chemical_list: D011134:Polysaccharides; D012996:Solutions; D002118:Calcium
keywords: Calcium; Polysaccharide; Seeds of Plantago asiatica L.; Solution and conformational characteristics