10种生、熟蔬菜中Vc含量及抗氧化性对比研究

通过用钼酸铵分光光度法测定生、熟青椒、尖椒、洋葱、胡萝卜、豆角、西红柿、茄子、苦瓜、芹菜、卷心菜10种蔬菜中Vc的含量。其反应原理是在SO42-离子存在的条件下,选用钼酸铵作为显色剂,利用反应生成的钼蓝,Vc在波长730nm处有强吸收,其浓度在2～22μg/mL范围内与吸收值呈良好的线性关系,该法简单、快速、准确测定Vc含量。结果表明,10种蔬菜在生熟两种情况时Vc含量有明显的变化,生蔬菜中Vc含量普遍高于相应熟蔬菜。最后,用DPPH法对比研究生熟蔬菜的抗氧化性,实验进一步证实Vc含量与其抗氧化性二者呈现一定的量效关系。

Comparative of vitamin C detecting and antioxidant capability on 10 kinds of raw and cooked vegetables

The vitamin C contents of 10 kinds of raw and cooked vegetables,green peppers,pepper,onion,carrot,bean,tomato,eggplant,bitter gourd,celery,cabbage were determined by using ammonium molybdate colorimetric method.The reaction principle is that the ammonium molybdate as a coloring reagent with vitamin C form the molybdenum blue in the presence of SO 4 2-ions,and the molybdophosphate complex has a strong absorption at a wavelength of 730 nm.A good linear relationship between vitamin C and adsorption value was obtained in the range of 2～22 μg/mL,the method is simple,rapid and accurate for detection of ascorbic acid.The results showed that there are significantly different of Vc content in the raw or cooked cases,and the Vc content of raw vegetables is generally higher than that of corresponding cooked vegetables.Finally,the antioxidant capabilities of the raw and cooked vegetables were compared with DPPH method,experiments further confirmed that both Vc content of vegetables and its antioxidant activity showed a certain dose-effect relationship.