Antioxidant Activity Of Zhenjiang Aromatic Vinegar

Modern epidemics such as adiposis, cardio-vascular diseases, cancer correlated nearly tolife style and dietetic habits. Demands for healthy food increased due to awareness of healthand the change of consume style. Simple medical treatment mode changed to the combinationof prevention, therapy and healing due to the development of science and technology. Fundamental study in free radical iatrology showed that oxygen radicals relate to hundredsof diseases. Antioxidants in food may be useful in vivo and can be used to prevent oxidationimpair. Brewed vinegar, characterized by its affluent nutriments and special pharmacologicalfunction, has a history of more than two thousands years. Vinegar has physiological effects,such as: promoting recovery from exhaustion, regulating blood glucose, blood pressure,antioxidant activity, anticancer, aiding digestion, stimulating the appetite, and promotingcalcium absorption. Related references centralized in Japan and the focus was the bioactivityof acetic acid which is one of the main components in vinegar. Systematical study on otheractive compounds and function mechanism hasn't been made. Vinegar uses have beenmentioned in past-dynasties medical literatures, however, few study about vinegar'sphysiological function was undertaken in these days. Zhenjiang aromatic vinegar is one of themost famous traditional vinegar in China. Study on the antioxidant activity of vinegar will behelpful for better understanding of the health protection mechanism,be favor to theexploitation of new products that can prevent cardio-vascular diseases and retardingsenescence. The study has great social significance and wide market foreground. This thesis systematically studied antioxidant activity of the different polar, differentmolecular fractions of vinegar and confirmed the more effective fractions. At the same time,this thesis also determined the in vitro and in vivo antioxidant activity of different fractions,discussed the source of antioxidants in vinegar and compared the antioxidant activitydifference of different kinds of vinegars. The experiment studied DPPH radical scavenging activities of different polar extracts invinegar, the results indicate that different polar extracts have DPPH scavenging activities at adifferent extent. Zhenjiang aromatic vinegar has weak radical scavenging activities comparedwith Kurosu. Organic acid, phenolic compounds, flavones and amino acid in vinegar wereconfirmed by chemical qualitative analysis. Zhenjiang aromatic vinegar extract (V4), obtainedby dealing concentrated ethanol supernate of vinegar with acetone and ethanol absolute, andsoluble fraction of Zhenjiang ethanol precipitation (V5) are more active components. PercentDPPH scavenging activities of V4 and V5 are 56.31% and 59.42%, respectively, at a finalconcentration 150 μg/mL. Percent DPPH scavenging activities for V4 and V5 both are71.44%. Yields of V4 are much higher than V5, 71.33 g/L and 16.05 g/L, respectively.On the base of former study, antioxidant activities of different fractions of V4 wereevaluated using different in vitro tests: the DPPH radical scavenging activity, the reducingpower, the amount of total phenolic compounds, the inhibitory effect on hydroxyl radical andsuperoxide anion radical, the inhibitory effect on oxidation of LDL. Zhenjiang aromaticvinegar extract (V4) and individual fractions, except F4, were found to have antioxidantactivities in all the model systems tested. Amounts of phenolic compounds have a positivecorrelation with DPPH radical scavenging activity, reducing power, inhibition of linoleic acidoxidation. DPPH scavenging activities of low molecular weight fraction (F4) is the highest,high molecular weight fractions (F1) the second. Active compounds in high molecular weightfractions of Zhenjiang aromatic vinegar are Maillard reaction products, melanoidins.Effect of concentrated Zhenjiang aromatic vinegar on oxidative modification of low densitylipoprotein (LDL) which was initiated by Cu2+ was studied. The results showed thatconcentrated Zhenjiang aromatic vinegar could inhibit the oxidative modification of LDL, andHV could block the oxidative reaction of the already oxidatively modified LDL.The senior model of Kunming-mice was built with D-galactose. Different doses of vinegarwere administered to the experimental mice. Liver index, spleen index and brain index weredetermined. MDA, SOD, GSH-Px of mice plasm, MDA and SOD of mice liver, brain weremeasured. The results indicated that HV could (1) effect greatly on liver index of mice(P<0.01), (2) increase the activities of SOD (P<0.05), GSH-Px/LPO ratio (P<0.01) andreduce the level of MDA in plasm, (3) reduce the level of MDA in liver (P<0.05).Changes of amount of total phenolic compounds, total flavones, and DPPH scavengingactivities during production were studied. The results indicated that (1)changes of amount oftotal phenolic compounds, total flavones have a positive relationship with percent DPPHscavenging activities, correlative coefficients were 0.9334 and 0.9353, respectively, (2)acetic acid fermentation period and decoction period have a higher influence on scavengingactivities. Storing time has a certain effect, short period of storing hasn't a distinct effect, (3)phenolic compounds, flavones and Maillard reaction products ( MRPs ) were main DPPHscavenging activity compounds in Zhenjiang aromatic vinegar.Amount of total phenolic compounds, total flavones and DPPH scavenging activity fordifferent kinds of vinegars were compared. The results indicate that (1) DPPH scavengingactivity of different kinds of vinegars has a positive correlation with amount of total phenoliccompounds, total flavones, the correlation coefficients were 0.9523 and 0.8691, respectively,(2) the higher content of phenolic compounds and flavones in Zhenjiang aromatic vinegarrespond for its higher scavenging activity.This research also indicated that (1) amount of total phenolic compounds, total flavonesand percent of DPPH scavenging activity can be used as discriminate index for differentkinds of vinegars, (2) new antioxidant may be formed during acetic acid fermentation periodand decoction period, and be worth further researching.