Study On The Antioxidant Activity And Antibacterial Property Of Wild Grape And Grape Wine

Grape phenolics mainly come from the skin and seed of grape，leaching into the wineduring the fermentation．Grape wine has a variety of active substances and good antioxidantactivity that can prevent a variety of diseases which caused by the free radicals．So its role inhealth care is more and more attention. This study selected wild grapes and the brewed wines forstudy and fruit grapes，classic wine grapes (Cabernet Sauvignon，Gernischt)，commercial winesas controls，compared the antioxidant and antibacterial activity of different varieties of grapesand wines as well as the active substance content and relevance．Study the dynamic changes ofantioxidant capacity，free radical scavenging ability and the content of the active substanceduring the fermentation process. To investigate the role of alcohol extraction to the dissolution ofgrape phenolics，extracting grape with different concentrations of alcohol for simulation test. Themain contents and results were as follows：(1) To evaluate the different varieties of grapes and wine, active substances content andantioxidant capacity，free radical scavenging capacity were compared．The results showed that：wild grapes traditional and Cabernet Sauvignon wines had high antioxidant activity and activesubstances content．The fruit grapes and wines’antioxidant activity and active substances contentwere the lowest．All indicators of Hezhou wild grape wine is the highest，its content of totalphenolics and total anthocyanins were2883mg GAE/L and3483mg/L，which were1.7timesand1.5times of Cabernet Sauvignon．(2)To study the dynamic changes of active substances and antioxidant activity during thewine fermentation process，monitoring the active substance content and antioxidant activity，freeradical scavenging ability in the process．The main fermentation process of wine is completed ina week．The total phenolic content and proanthocyanidins content had been carried out with theprocess increases during the fermentation and aging process．Total anthocyanin content of thefirst three days rise rapidly，and reaching a peak at the end of primary fermentation period．Then the total anthocyanin content declined gradually．The total antioxidant activity，DPPH radicalscavenging，oxygen radical scavenging，hydroxyl radical scavenging increased with thefermentation process．All of them were associated with total phenolic content (the correlationcoefficients were greater than0.95).(3)The resistance of wine phenolics for Gram-positive bacteria was more thanGram-negative bacteria.The antibacterial property of wild grape was superior to traditionalCabernet Sauvignon, Gernischt wine and other fruit grape wine. The antibacterial property of theHezhou wild grape was the most prominent.