College of Life Science, Dalian Nationalities University, Dalian 116600, China.
Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian 116600, China.
Molecules. 2019 Jun 26;24(13):2368. doi: 10.3390/molecules24132368.
The objective of this study was to develop an ultrasonic-assisted procedure for the extraction of total phenolics from L blossoms (CAB) and evaluate the free radical scavenging activity and anti-HMG-CoA reductase activity of the total phenolics. In this work, a Box- Behnken design based on single-factor experiments was used to explore the optimum extraction process. Under the optimum conditions (extraction solvent 70.31% ethanol, extraction temperature 61.94 °C, extraction time 51.73 min, and liquid-to-solid ratio 35.63 mL/g), the extraction yield of total phenolics was 95.84 mg gallic acid equivalents (GAE)/g dry matter (DM), which was highly consistent with the theoretical value (96.12 mg GAE/g DM). The higher contents of total phenolics and five main phenolic compounds obtained from the optimized ultrasonic-assisted extraction (UAE) proved its efficiency when compared with conventional heat reflux extraction (HRE). The total phenolic extract showed excellent free radical scavenging properties against 1,1-diphenyl-2-picrylhydrazyl radical (DPPH·), 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) radical (ABTS·), hydroxyl radical (·OH) and superoxide anion radical (·O), with IC values of 197.007, 83.878, 218.643, and 158.885 μg/mL, respectively; the extracts also showed good inhibition of β-hydroxy-β-methylglutaryl-CoA reductase (HMG-CoA reductase) activity, with an IC value of 117.165 μg/mL. Total phenolics from CAB could be a potential source of natural free radical scavenger and HMG-CoA reductase inhibitor.
本研究旨在开发一种超声辅助法从荔枝花（CAB）中提取总酚，并评价总酚的自由基清除活性和对 HMG-CoA 还原酶的抑制活性。在这项工作中，采用基于单因素实验的 Box-Behnken 设计来探索最佳提取工艺。在最佳条件下（提取溶剂 70.31%乙醇，提取温度 61.94°C，提取时间 51.73 分钟，液固比 35.63 mL/g），总酚的提取率为 95.84 mg 没食子酸当量（GAE）/g 干物质（DM），与理论值（96.12 mg GAE/g DM）高度一致。与传统的热回流提取（HRE）相比，从优化的超声辅助提取（UAE）中获得的总酚和五种主要酚类化合物的含量更高，证明了其效率。总酚提取物对 1,1-二苯基-2-苦基肼基（DPPH·）、2,2'-联氮-双（3-乙基苯并噻唑啉-6-磺酸）自由基（ABTS·）、羟基自由基（·OH）和超氧阴离子自由基（·O）具有优异的自由基清除性能，IC 值分别为 197.007、83.878、218.643 和 158.885 μg/mL；提取物对β-羟-β-甲基戊二酰基辅酶 A 还原酶（HMG-CoA 还原酶）活性也有很好的抑制作用，IC 值为 117.165 μg/mL。荔枝花中的总酚可能是天然自由基清除剂和 HMG-CoA 还原酶抑制剂的潜在来源。
