Tanase Corneliu, Mocan Andrei, Coșarcă Sanda, Gavan Alexandru, Nicolescu Alexandru, Gheldiu Ana-Maria, Vodnar Dan C, Muntean Daniela-Lucia, Crișan Ovidiu
Department of Pharmaceutical Botany, University of Medicine, Pharmacy, Sciences and Technology, 540139 Târgu Mureș, Romania.
Department of Pharmaceutical Botany, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca 400337, Romania.
Antioxidants (Basel). 2019 Sep 19;8(9):417. doi: 10.3390/antiox8090417.
The present study aimed, on the one hand, to improve the yield of microwave assisted extraction (MAE) of polyphenols from beech bark by using a design of experiments (DoE) approach. On the other hand, beech bark extracts (BBE) were characterized in terms of their phytochemical profile and evaluated for biological potential (antioxidant, antibacterial, antifungal, antimutagen, -α-glucosidase, and -tyrosinase). The extraction time varies with the amount of extracted total phenolic content (TPC). The microwave power favors TPC extraction but in different proportions. The optimum conditions which gave the highest TPC (76.57 mg GAE/g dry plant material) were reached when the microwave power was 300 W, extraction time was 4 min, and the solvent was an ethanol-water (50:50) mixture. The practical value of TPC after a controlled experiment was 76.49 mg GAE/g plant material. The identified compounds were vanillic acid, gallic acid, epicatechin, catechin, protocatechuic acid, chlorogenic acid, ferulic acid, and isoquercitrin. The antioxidant potential of BBEs was demonstrated by experiments. The BBEs were active against , , , , and species. All extracts were antimutagenic and expressed an inhibition on α-glucosidase and tyrosinase activity. Regarding antimutagen activity, the assayed extracts may be considered to have low or no antimutagen effects.
本研究一方面旨在通过实验设计（DoE）方法提高从山毛榉树皮中微波辅助提取（MAE）多酚的产率。另一方面，对山毛榉树皮提取物（BBE）进行了植物化学特征分析，并评估了其生物活性（抗氧化、抗菌、抗真菌、抗诱变、α - 葡萄糖苷酶抑制和酪氨酸酶抑制）。提取时间随提取的总酚含量（TPC）量而变化。微波功率有利于TPC的提取，但比例不同。当微波功率为300 W、提取时间为4分钟且溶剂为乙醇 - 水（50:50）混合物时，达到了最高TPC（76.57 mg GAE/g干植物材料）的最佳条件。对照实验后TPC的实际值为76.49 mg GAE/g植物材料。鉴定出的化合物有香草酸、没食子酸、表儿茶素、儿茶素、原儿茶酸、绿原酸、阿魏酸和异槲皮苷。实验证明了BBE的抗氧化潜力。BBE对 、 、 、 和 物种具有活性。所有提取物均具有抗诱变作用，并对α - 葡萄糖苷酶和酪氨酸酶活性有抑制作用。关于抗诱变活性，所测定的提取物可被认为具有低抗诱变作用或无抗诱变作用。
