对野菊〔Dendranthema indicum (L.) Des Moul.〕花的60%乙醇提取物中酚类成分的组成与含量进行了分析,并研究了该提取物对.O2-、.OH和DPPH自由基的清除能力以及防牛奶霉变的能力。结果表明,野菊花60%乙醇提取物主要含有黄酮类成分和一定量的酚酸类成分;酚酸类成分中绿原酸和咖啡酸的含量分别为20.74 mg.g^-1和1 420.57μg.g^-1;总黄酮含量为490.50 mg.g^-1,其中槲皮素、木犀草素、芹菜素、刺槐素和蒙花苷的含量分别为31.05、22.67、23.09、30.71和107.23 mg.g^-1,分别占总黄酮含量的6.33%、4.62%、4.71%、6.26%和21.86%。该提取物对.O2-、.OH和DPPH自由基均有一定的清除能力,在实验设置的浓度范围内,对3种自由基的清除率与该提取物浓度基本呈正相关关系,回归方程分别为y=0.273x+38.540、y=1.208x+2.761和y=2.032x+45.330,IC50分别为41.98μg.mL^-1、39.11 mg.mL^-1和2.30 mg.mL^-1,其中对DPPH自由基的清除能力最强,且其IC₅₀略高于V_C。在牛奶中添加一定量的野菊花60%乙醇提取物(质量体积分数0.012 5%~0.2%),牛奶中的各级霉斑数量、病情指数以及霉菌孢子数均低于空白处理组,且该提取物的这种防霉变能力与其浓度呈一定的正相关关系;其中0.2%的野菊花60%乙醇提取物的防霉变能力高于质量体积分数0.01%山梨酸钾。实验结果显示,野菊花60%乙醇提取物具有较高的抗氧化能力和显著的防霉变能力,可作为食品防腐剂进行开发利用。

Compositions and contents of phenolic compounds in 60% ethanol extract from  Dendranthema Indicum (L.) Des Moul. flower were analyzed, and its scavenging ability to free radicals of ·O ^2-,·OH and DPPH and its mild ewproof ability to milk were alsostudied. The results show that the 60% ethanol extract mainly contains flavonoids and a certain amount of phenolic acids. In phenolic acids, contents of chlorogenic acid and caffeic acid are 20. 74mg·g^{- 1}and 1 420. 57μg·g^{- 1}, respectively. Total flavonoids content in the extractis 490.50mg·g^{- 1}, in which contents of quercetin, luteolin, apigenin, acacetin andlinarin are 31.05, 22.67, 23.09, 30.71and 107.23mg·g^{- 1}, accounting for 6.33%,4.62%, 4. 71%, 6. 26% and 21. 86% of total flavonoids content, respectively. The extract has a certain scavenging ability to free radicals of ·O ^2-,·OH and DPPH, and the scavenging rate generally appears a positive correlation with the extract concentration in concentration range of each experiment. The linear regression equations between scavenging rate and concentration of the extract are y= 0.273x+38.540, y= 1.208x+ 2.761andy= 2.032x+ 45.330, respectively, and IC₅₀ of the extracts to ·O ^2-,·OH and DPPH are 41.98μg·mL^{- 1,} 39.11mg·mL^{- 1} and 2.30 mg·mL^{- 1},respectively. In which,  the scavenging ability to DPPH free radical is the strongest, and its IC₅₀ is slightly higher than that of V_C. When a certain amount of the extract (0.012 5%- 0.2%) added in milk, mildew spot number, disease index and  spore number in the milk all are lower than those of the blank group, and the mildewproof baility has a positive correlation with the extract concentration. And the mildewproof ability of  0. 2% extract is high than that of 0.01% potassium sorbate. It is suggested that 60% ethanol extract from D.indicum flower has a stronger oxidation resistance and a significant mildewproof ability, so it can be further exploited and utilized as food antiseptic.