Department of Tea Science, Zhejiang University, Hangzhou 310058, China; E-Mails:
Int J Mol Sci. 2011;12(10):6856-70. doi: 10.3390/ijms12106856. Epub 2011 Oct 14.
Supercritical carbon dioxide (SC-CO(2)) extraction of bioactive compounds including flavonoids and phenolics from Ampelopsis grossedentata stems was carried out. Extraction parameters such as pressure, temperature, dynamic time and modifier, were optimized using an orthogonal array design of L(9) (3(4)), and antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and ferrous ion chelating (FIC) assay. The best conditions obtained for SC-CO(2) extraction of flavonoids was 250 bar, 40 °C, 50 min, and with a modifier of methanol/ethanol (1:3, v/v), and that for phenolics extraction was 250 bar, 40 °C, 50 min, and with a modifier of methanol/ethanol (1:1, v/v). Meantime, flavonoids and phenolics were found to be mainly responsible for the DPPH scavenging activity of the extracts, but not for the chelating activity on ferrous ion according to Pearson correlation analysis. Furthermore, several unreported flavonoids such as apigenin, vitexin, luteolin, etc., have been detected in the extracts from A. grossedentata stems.
采用 L(9) (3(4)) 正交设计，研究了超临界二氧化碳（SC-CO(2))）从大血藤茎中萃取包括类黄酮和酚类化合物在内的生物活性化合物的萃取参数，如压力、温度、动态时间和改性剂，并通过 2,2-二苯基-1-苦基肼（DPPH）自由基清除试验和亚铁离子螯合（FIC）试验评价了提取物的抗氧化活性。SC-CO(2) 萃取类黄酮的最佳条件为 250 bar、40°C、50 min，并用甲醇/乙醇（1:3，v/v）作为改性剂；萃取酚类化合物的最佳条件为 250 bar、40°C、50 min，并用甲醇/乙醇（1:1，v/v）作为改性剂。同时，根据 Pearson 相关分析，发现类黄酮和酚类化合物主要负责提取物的 DPPH 清除活性，但对亚铁离子的螯合活性没有影响。此外，还在大血藤茎提取物中检测到几种未报道的类黄酮，如芹菜素、牡荆素、木犀草素等。
