| Nowadays, the research of natural antioxidants is the important part of Chinese traditional medicine researching. Natural antioxidant has many good functions. On the one hand, it is used as food additive. Some research showed that industrial synthetic antioxidants such as TBHQ, BHT have strong toxicity. Some of them have been forbidden in Europe. The natural antioxidants extracted from plant is safe and effective, so it could become the substitute for synthetic antioxidants and has remarkable practicality. On the other hand, the free radical in vivo has closely connection with engendering of the disease such as tumors, doddery, inflammation , etc. Some free radical such as super oxide free radical(O2-·), hydroxyl free radical(·OH), MDA have obvious toxicity. Some enzymes exit in body such as SOD which have antioxidant activity has very important function. Some research showed that antioxidants can strengthen the function of antioxidant enzymes. Therefore, natural antioxidants has vast vistas.The research for antioxidant activity is the important part in herbal modernization. Many Chinese traditional medicines comprise antioxidant activity material. Water-caltrop exist in many areas and be comprised in Chinese Pharmacopoeia. But it hadn't been used widely and efficiently yet. In resent years, Niu fenglan and some others research a lot about water-caltrop(mainly on Northeast Water-caltrop) and get many achievements, some of which have proved the water- caltrop function of anti-cancer. However, nobody researched the antioxidant activity of water- caltrop. One purpose of this research is to discover the antioxidant activity of water-chestnut, the other is to build a research method on it.The author had chose TBHQ, BHT, sodium D-isoascorbate as the contrasts. This three synthetic antioxidants has been wild used, and they has high activity. They come from two kind of important antioxidant-free radical inhibitor and oxygen scavenger. By contradistinguished with them, It can be not only be proved that the extract of water-caltrop has antioxidant activity, but also has the elementary study on the mechanism of extraction of water-caltrop's antioxygenic property.There are many means to score antioxidant activity. This paper studied on water-caltrop by spectrophotometry and Titration-Measurements . The instrument used in spectrophotometry is widely used, and it is cheap to use. But spect- -rophotometry can be interfered by temperature etc, and there could be more stochastic errors. So the author score the antioxidant activity of the extraction of water-caltrop by the distinguishement with contradistinguish.The study tested the antioxidant activity of northeast water-caltrop extractions on super oxide free radical(O2-·), hydroxyl free radical(·OH), deoxidization, lipid peroxidate. Extractions were extracted by different methods. They were raw extract A(A), raw extract B(B), raw extract C(C), raw extract D(D), raw extract E(E). A is alcohol precipitate from northeast water extract. B is the precipitation. C is essential oil. D is 75% alcohol extract. E is methanol extract.Some conclusions can be made:1. Five extractions'extraction rate: A:44.03g/kg ;B:9.81 g/kg ;C:0.10 g/kg;D:7.42 g/kg;E:3.10 g/kg2. To super oxide free radical(O2-): antioxidant activity of B is higher than TBHQ and the others in same concentration. The antioxidant activity of B is weaker and E has weakest activity. The antioxidant activity of D can not be determined. At the beginning of experiment, the Inhibitory rates of O2- are showed below. They were: TBHQ: -20%~50%,sodium D-isoascorbate:27%~94%, A:-27%~64%, B: 4%~57%, E :-5%~22%. Beside, A has the highest extraction rat which is 5~10 times higher than the others'. It shows that the active components extraction rat of A is the highest. It is also find that the response curves of E and TBHQ are similar. It shows that E and TBHQ have the similar antioxidant mechanism.3. To deoxidization : the extractions of northeast water-caltrop all showed deoxidization activity. The activity of them were similar with contrasts beside B. For the activity of B was lower than the others remarkably which is different from its antioxidant activity to O2-, it could be concluded that there are more than one kind of antioxidant activity materials in northeast water-caltrop.4. To the hydroxyl free radical(·OH): the quality traits'were: TBHQ:10%~57%,sodium D-isoascorbate:11%~39%,A:13%~50%,B:8%~27%,D:41%~80%, E:46%~85%. There were remarkable concentration dependents. Activities of D and E were stronger then the others. A is weaker and B is weakest. But their activities were similar with contrasts. That also proved there are more than one kind of antioxidant activity materials in northeast water-caltrop and there are not only hydrophile but also lipophilic material.5. To lipid peroxidate: TBHQ and BHT has good antioxidant activities to lipid peroxidate. A, D, E had the similar role when they have 10 times higher concentration . B and C had no activity in this experience. A, D, E were proved to have activity, and there were concentration dependents.6. A is the just one to study more.This paper had discoved the antioxidant activity of northeast water- caltrop, and build a research method on it. It is a start to full-scale the antioxidant activity of water- caltrop.
|
PDF Full Text Request