Department of Food Science, Faculty of Food Science and Technology, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Food Safety and Food Integrity (FOSFI), Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Molecules. 2018 Feb 13;23(2):402. doi: 10.3390/molecules23020402.
This study evaluated the efficacy of various organic solvents (80% acetone, 80% ethanol, 80% methanol) and distilled water for extracting antioxidant phenolic compounds from turmeric, curry leaf, torch ginger and lemon grass extracts. They were analyzed regarding the total phenol and flavonoid contents, antioxidant activity and concentration of some phenolic compounds. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and the ferric reducing antioxidant power (FRAP) assay. Quantification of phenolic compounds was carried out using high-performance liquid chromatography (HPLC). All the extracts possessed antioxidant activity, however, the different solvents showed different efficiencies in the extraction of phenolic compounds. Turmeric showed the highest DPPH values (67.83-13.78%) and FRAP (84.9-2.3 mg quercetin/g freeze-dried crude extract), followed by curry leaf, torch ginger and lemon grass. While 80% acetone was shown to be the most efficient solvent for the extraction of total phenolic compounds from turmeric, torch ginger and lemon grass (221.68, 98.10 and 28.19 mg GA/g freeze dried crude extract, respectively), for the recovery of phenolic compounds from curry leaf (92.23 mg GA/g freeze-dried crude extract), 80% ethanol was the most appropriate solvent. Results of HPLC revealed that the amount of phenolic compounds varied depending on the types of solvents used.
本研究评估了不同有机溶剂（80%丙酮、80%乙醇、80%甲醇）和蒸馏水从姜黄、咖喱叶、火炬姜和柠檬草提取物中提取抗氧化酚类化合物的效果。对总酚和类黄酮含量、抗氧化活性以及一些酚类化合物的浓度进行了分析。抗氧化活性通过 2,2-二苯基-1-苦基肼（DPPH）自由基清除测定法和铁还原抗氧化能力（FRAP）测定法来确定。酚类化合物的定量采用高效液相色谱法（HPLC）进行。所有提取物均具有抗氧化活性，但不同溶剂在提取酚类化合物方面的效率不同。姜黄表现出最高的 DPPH 值（67.83-13.78%）和 FRAP（84.9-2.3 mg 槲皮素/g 冷冻干燥粗提取物），其次是咖喱叶、火炬姜和柠檬草。虽然 80%丙酮被证明是从姜黄、火炬姜和柠檬草中提取总酚类化合物的最有效溶剂（分别为 221.68、98.10 和 28.19 mg GA/g 冷冻干燥粗提取物），但对于从咖喱叶中回收酚类化合物（92.23 mg GA/g 冷冻干燥粗提取物），80%乙醇是最合适的溶剂。HPLC 结果表明，酚类化合物的含量取决于所使用的溶剂类型。
