Effects of grafting on chemical constituents, toxicological properties, antithrombotic activity, and myocardial infarction protection of styrax secreted from the trunk of Liquidambar orientalis Mill.

Styrax, the balsam refined from the trunk of Liquidambar orientalis Mill. has a variety of applications in the perfumery and medical industry, especially for use in traditional Chinese medicine. However, the resources of styrax are in shortage due to being endangered of this plant. Grafting can improve the adaptability of plants to unfavorable environmental conditions. We tried to graft the L. orientalis Mill. on L. formosana Hance which was widely distributed in Jiangsu and Zhejiang provinces of China in an attempt to obtain styrax from grafted L. orientalis Mill. (grafted styrax, SG). Whether SG can become an alternative application of commercially available styrax (SC) need be further investigated. The components of SG were analyzed by GC-MS, and the results showed that the chromatograms of SG, SC, and styrax standard (SS) were consistent. The ration of 12 major chemical components based peak area in SG, SC, and SS were 93.95%, 94.24%, and 95.86% respectively. The assessment of toxicity, antithrombotic activity, and myocardial infarction protection of SG and SC was evaluated by using the zebrafish model, the results showed that SG and SC have the similar toxicological properties as evidenced by acute toxicity test, developmental toxicity and teratogenicity, and long-term toxicity test. Both SG and SC significantly decreased the thrombosis and increased blood flow velocity of zebrafish induced by adrenaline hydrochloride, inhibited myocardial apoptosis, myocardial infarction and myocardial inflammation in zebrafish induced by isoproterenol hydrochloride. Moreover, SG had an obvious improvement effect on cardiac output, while SC has no effect. Collectively, SG is similar to SC in chemical composition, toxicological properties, antithrombotic activity, and myocardial infarction protection effects, and may be used as a substitute for styrax to reduce the collection for wild L. orientalis Mill. and increase the available styrax resources.