5 种梅干菜的酚类化合物及抗氧化能力比较分析

以市售5 种梅干菜为研究对象，测定梅干菜酚类化合物的含量，用高效液相色谱-串联质谱（high performance liquid chromatography-tandem mass spectrometry，HPLC-MS/MS）法鉴定梅干菜酚类化合物的种类，并用4 种抗氧化能力评价方法评价梅干菜。结果表明，市售5?种梅干菜所含的酚类化合物含量和各酚类化合物所占的比例及其抗氧化能力差异显著。其中咕咕鲜牌梅干菜（GGX）的总酚含量为14.18?mg?GAE/g，总黄酮含量为7.10?mg?RE/g，2,2’-联氮-双-（3-乙基苯并噻唑啉-6-磺酸）二铵盐（2,2’-azino-bis(3-ethylbenzthiazoline-6-sulphonate)，ABTS）法、铁离子还原（ferric reducing antioxidant power，FRAP）法、1,1-二苯基-2-三硝基苯肼法和氧自由基吸收能力（oxygen radical absorbance capacity，ORAC）法测得的抗氧化能力分别为28.09、32.88、31.72?μmol?TE/g和445.55?μmol?TE/g，显著高于其他4?种梅干菜。其次，利用HPLC-MS/MS法分析鉴定出梅干菜中共含有17?种酚类化合物，包括9?种类黄酮和8?种酚酸。其中，梅干菜中的类黄酮主要有野漆树苷、山柰酚、异鼠李素、柚皮素等；酚酸主要有阿魏酸、香豆酸和肉桂酸等。此外，4?种抗氧化能力评价方法中，ABTS与FRAP相关性最高，相关系数为0.967；ORAC法测得的梅干菜抗氧化能力显著高于其他3?种方法；而ABTS法与梅干菜的抗氧化剂相关性最高，最适合评价梅干菜的总抗氧化能力。综上所述，不同种类市售梅干菜的酚类化合物含量和抗氧化能力均不同，其中，GGX总酚含量最高、抗氧化能力最强。

Phenolic Compounds and Antioxidant Capacity of Five Pickled and Dried Mustard Brands

In this study, the contents of phenolic compounds in five commercial brands of pickled and dried mustard were analyzed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and their antioxidant activity was evaluated by four antioxidant capacity assays. The five brands were Xianhong (XH), Guguxian (GGX), Guanhuawang (GHW), and homemade products A and B (JTA and JTB). The results showed that the total phenol contents, the proportions of different phenolic classes and antioxidant activity were significantly different among five pickled and dried mustard brands. The total phenol content of GGX was 14.18 mg GAE/g, the total flavonoid content was 7.10 mg RE/g, and the antioxidant activity was 28.09, 31.72, 32.88 and 445.55 μmol TE/g as measured by 2,2’-azino-bis(3-ethylbenzthiazoline-6-sulphonate (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC) assays, respectively, which was significantly higher than that of the other four brands. A total of 17 phenolic compounds, including 9 flavonoids and 8 phenolic acids, were identified by HPLC-MS/MS. Among these, the major flavonoids were identified as rhoifolin, kaempferol, isorhamnetin, and naringenin, ferulic acid, p-coumaric acid and t-cinnamic acid were the main phenolic acids. In addition, among the four antioxidant capacity assays, the correlation between ABTS and FRAP was the highest with a correlation coefficient of 0.967; the antioxidant capacity of pickled and dried mustard evaluated by the ORAC method was significantly higher than those by three other methods; the ABTS method exhibited the highest correlation coefficient with antioxidants, which was the most suitable for evaluating the total antioxidant capacity of pickled and dried mustard. In summary, the total phenol contents and antioxidant capacities of different brands of commercially available pickled and dried mustard were different. Among them, GGX had the highest total phenol content and strongest antioxidant capacity.