Department of Food Science and Technology, Faculty of Agro-Industry, Kasetsart University, Bangkok 10900, Thailand.
Department of Chemical Engineering, Faculty of Engineering, Kasetsart University, Bangkok 10900, Thailand.
Molecules. 2022 Mar 24;27(7):2085. doi: 10.3390/molecules27072085.
Mung bean seed coat (MBC) is a by-product of the mung bean processing industry. It contains a large number of phenolic compounds with therapeutic anti-inflammatory, anti-diabetic and antioxidant properties. This research aimed to investigate the optimum conditions for phenolic and flavonoid extraction from MBC by pressurized liquid extraction (PLE). Response surface methodology (RSM) was used to study the effects of temperature (80-160 °C), pressure (1200-1800 psi) and ethanol concentration (5-95%) on total phenolic content (TPC), total flavonoid content (TFC) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity (ABTS). Scale-up extraction was also performed. The optimum conditions for extraction were 160 °C, 1300 psi and 50% ethanol. Under optimum conditions, the TPC was 55.27 ± 1.14 mg gallic acid equivalent (GAE)/g MBC, TFC was 34.04 ± 0.72 mg catechin equivalent (CE)/g MBC and ABTS scavenging activity was 195.05 ± 2.29 mg trolox equivalent (TE)/g MBC. The TFC and ABTS scavenging activity of the extracts obtained at the pilot scale (10 L) was not significantly different from the laboratory scale, while TPC was significantly increased. The freeze-dried MBC extract contained vitexin and isovitexin 130.53 ± 17.89, 21.21 ± 3.22 mg/g extract, respectively. In conclusion, PLE was able to extract phenolics, flavonoids with ABTS scavenging activity from MBC with the prospect for future scale-up for food industry.
绿豆种皮（MBC）是绿豆加工工业的副产物。它含有大量具有治疗抗炎、抗糖尿病和抗氧化特性的酚类化合物。本研究旨在通过加压液体萃取（PLE）探索从 MBC 中提取酚类和类黄酮的最佳条件。响应面法（RSM）用于研究温度（80-160°C）、压力（1200-1800 psi）和乙醇浓度（5-95%）对总酚含量（TPC）、总黄酮含量（TFC）和 2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸）清除活性（ABTS）的影响。还进行了放大提取。萃取的最佳条件为 160°C、1300 psi 和 50%乙醇。在最佳条件下，TPC 为 55.27±1.14 mg 没食子酸当量（GAE）/g MBC，TFC 为 34.04±0.72 mg 儿茶素当量（CE）/g MBC，ABTS 清除活性为 195.05±2.29 mg 维生素 E 当量（TE）/g MBC。在中试规模（10 L）下获得的提取物的 TFC 和 ABTS 清除活性与实验室规模没有显著差异，而 TPC 则显著增加。冻干的 MBC 提取物含有牡荆素和异牡荆素 130.53±17.89、21.21±3.22 mg/g 提取物，分别。总之，PLE 能够从 MBC 中提取具有 ABTS 清除活性的酚类、类黄酮，具有未来在食品工业中放大的前景。
