Tuesday, 7 December 2010
The sulfated Lycium barbarum polysaccharide (LBP) were prepared by chlorosulfonic acid–pyridine (Py-SO3) method according to orthogonal L9(3)4 test under microwave irradiation. Eight sulfated sLBP, with various degrees of sulfate (DS) and the number average molecular weight (Mw), were obtained and their anti-HIV activities were compared by MTT and ELISA assay. The results indicated that when DS within the scope of 0.2–0.5 and the Mw in the range of 40–50 kDa, sLBP exhibited significantly strong inhibition of HIV activity, and it was confirmed by real-time biomolecular interaction analysis (BIAcore). The optimum sulfation conditions were reaction temperature of 45°C, the molar ratio of Py-SO3 to LBP of 2:1 and the reaction time of 6 min at the microwave power of 45W in DMF.