Monopalmityloxy Shikimic Acid: Enzymatic Synthesis and Anticoagulation Activity Evaluation

摘要

Shikimic acid is a natural bioactive product, which has anti-thrombosis activity, but the poor bioavailability and blood-brain barrier permeability limited its general therapeutic utilization. By monoacylation, a long fatty acid residue can be linked to offer it desirable modified polarity. In this paper, the biosynthesis system has been established and a series of Monoalkanoloxy shikimic acids have been successfully synthesized from shikimic acid and corresponding alkanoic acid catalyzed by Novozym 435 in 2-methyl-2-butanol. After collection and purification,the monopalmityloxy shikimic acid, as the representative, has been evaluated for its anticoagulation activity in vivo via OS. After reaction for 24~48 h at 55°C, 0.10 kPa,the solid shikimic acid has been observed to dissolved in the reaction system completely. The subsequent HPLC-MS analysis showed that the monopalmityloxy shikimic acid, as the only product, had been formed and the overall conversion rate was over 70%. After collection and purification, the acute toxicity test has been carried out for such product via mice. And its anti-thrombosis has been evaluated through Arteriovenous shunt model of rats and through the determination of TT, PT and APTT via rats. The result showed that it had anti-thrombosis activity, could prolong the coagulating time and bleeding time in vivo and lengthen the coagulating time in vitro. Compared with control group, the differences of the treatment group and aspirin group of rats are significant (P<0.05) for PT and TT, and very significant (P<0.01) for APTT. It suggested that the product had the anticoagulation activity. The mechanism might be the co-action of the inhibition of intrinsic coagulation and the inhibition of extrinsic coagulation, and the inhibiting effect to intrinsic pathway is stronger than that to extrinsic pathway.