油茶粕中黄酮化合物的分离鉴定及抗氧化性研究

Extraction,antioxidant activity of flavonoids from oil-tea camellia seed cake

为了探索油茶粕中黄酮化合物的分子组成及其抗氧化活性,本研究运用优化的分离纯化方法对油茶粕中黄酮进行粗提和HZ816大孔吸附树脂富集纯化,然后再经硅胶柱对其黄酮化合物层析,得到2种黄酮化合物,分别记为化合物Ⅰ和化合物Ⅱ。随后利用核磁共振、质谱、红外和紫外光谱对上述分离得到的2种黄酮化合物进行结构鉴定。结果表明:这2种物质分别为山奈酚3-O-[2-O-β-D-木糖-6-O-α-L-鼠李糖]-β-D-葡萄糖苷(化合物Ⅰ)和山奈酚3-O-[2-O-β-D-半乳糖-6-O-α-L-鼠李糖]-β-D-葡萄糖苷(化合物Ⅱ)。对分离的黄酮化合物采用1,1-二苯基-3-硝基苯肼自由基清除法(DPPH法)、邻苯三酚自氧化法在体外进行抗氧化实验,结果显示总黄酮、化合物Ⅰ和化合物Ⅱ清除DPPH自由基半抑制浓度(IC_(50))分别为0.44、1.88、2.41 mg/m L,清除超氧阴离子IC_(50)分别为1.38、1.13、1.29 mg/m L。

To explore the molecular composition and antioxidant activity of flavonoids in oil- tea camellia seed cake, the optimized extraction and purification method was used to purify the flavonoids in the seed cake and the HZ816 macroporous adsorption resin was used for the enrichment and purification, then the silica gel column was used to chromatograph the flavonoid compounds and two flavonoid compounds were obtained,which were designated as compounds I and II.The two flavonoid compounds were identified by nuclear magnetic resonance, mass spectrometry, infrared and ultraviolet spectroscopy. The results revealed that ： the two substances were kaempferol 3- O- [ 2- O-β- D- xylopyranosyl-6- O- α- L- rhamnopyranosyl ] -β-D- glucopyranoside （ I ） and kaempferol 3 - O - [ 2 - O -β- D - galactopyranosyl - 6 - O - α- L- rhamnopyranosyl ] -β- D - glucopyranoside（ II ）.The antioxidant test was carried out on the isolated flavonoid compounds using 1,1- diphenyl-3- nitrophenylhydrazine radical scavenging（ DPPH method）and pyrogallol autoxidation in vitro.The results showed that the IC50 of DPPH free radicals of the total flavonoids,compound I and compound II was 0.44,1.88,2.41 mg/mL respectively,and the IC50 of superoxide anion free radicals was 1.38,1.13,1.29 mg/mL respectively.