Font Size: a A A

Natural Food Antioxidant Alpha-ht

Posted on:2004-01-31Degree:MasterType:Thesis
Country:ChinaCandidate:Z Y HuFull Text:PDF
GTID:2191360155453751Subject:Food Science and Engineering
Abstract/Summary:PDF Full Text Request
Chem-antioxidants were used for food industry for a long time, but more and more results were proved that they were some side-effects for human being. Therefore, it is being a hot topic to look for nature antioxidants with high activity, safety, economics for food industry. In this paper, the active compound -α-HT from Ampelopsis cantoniensis was studied on its extraction, purification, detection and antioxidative activity. The extraction and purification of α-HT were studied firstly. Results were showed: α-HT was extracted from soft leaves and stems of Ampelopsis cantoniensis by hot water, and then purified by re-crystallization. At last, α-HT from 40% purity to 99% purity was produced by this method. During the same experiments, some other results were obtained, for example, the content of α-HT is more 39% in the extracted samples which extracted from spring samples and the extraction rate of spring sample is 50%. The suitable season for this botanical resource is in spring and in summer. Active carbon had better function on purification of α-HT, though it also expressed some side-effects for the purification. A-RP-HPLC method for detection and measurement of α-HT was developed secondly. Operating conditions were UV-291nm detection, Nova-pak C18 column 150mm×3.9mm i.d., and the flow phase of v(methanol)/v(water)=(36:64,plus 0.1% phosphoric acid) ,the flow speed of 1.0ml/min , 10ul injection volume , 30℃temperature for column. α-HT is in the soft parts of Ampelopsis cantoniensis and was varied from 27-28% in the young leaves to 11% in the tender stem. The antioxidative activities of α-HT and TBHQ were studied comparatively in different systems. In TPPH(1,1-diphenyl-2-picrylhydrazyl) system, the scavenging activities of α-HT was equal to or more than that of TBHQ, when their adding amount differed from 0.02% to 0.04%.In linolenic acid system, The antioxidative effect ofα-HT was more better than that of TBHQ. There were some differences between different purity antioxidants and their antioxidative effects. For example, The antioxidative effect of α-HT with 60%, 80%, 90% purity was more better than that of each other in pig oil, but only better in 20 days in plant oil system. The antioxidative effect of α-HT was very good in oil industry. For example, when its adding amount was 0.02% in plant oil, pig oil, moon cake, taosou food, the time for lipid peroxidation was delayed 2,2.4,3.2 and 5.5 times. At last, some factors influencing on antioxidative effect of α-HT were studied. The suitable adding amount for 60% α-HT is 0.06%. α-HT can express its antioxidative activity in acid medium, the antioxidative activity is the best in PH 4-5. All the results above are showed that α-HT would be developed into a new kind of nature antioxidant.
Keywords/Search Tags:natural antioxidant, α-HT, production, detecting method, antioxidative activity, application
PDF Full Text Request
Related items