Conformational properties of high molecular weight heteropolysaccharide isolated from seeds of Artemisia sphaerocephala Krasch

Abstract: The conformational properties of a high molecular weight polysaccharide (60P) extracted from Artemisia sphaerocephala Krasch (ASK) were investigated. The M w and R g of 60P were obtained using both static light scattering and HPSEC techniques, which were 590 kDa and 56 nm, respectively. Dynamic light scattering measurement indicated that 0.5 M NaOH solvents exhibited the ability to reduce/eliminate aggregates of 60P. 60P in 0.5 M NaOH showed strong concentration dependence, but minimal angular dependence. The average structure parameter ρ (R g/R h) value of 1.75 indicated that 60P exhibited a random coil conformation in 0.5 M NaOH solution. The conformational parameters (derived from R g vs M w and R h vs M w) from HPSEC also suggested a random coil conformation of 60P in 0.1 M NaNO3 solution (eluent for HPSEC). The characteristic ratio and the persistence length obtained from the random flight model and wormlike cylinder model both indicated a semi-flexible structure of 60P. [Copyright &y& Elsevier]