Study On Extraction Techniques Of Resveratrol And Difference Analysis Of Resveratrol Content In Grape Tissue

Resveratrol is a kind of poly phenolic substance existing in polygonum, grape, peanut etal, which has many keeping health functions. Resveratrol also have cardiovascular protection, anti-oxidation, anti-cancer, anti-bacterial anti-inflammatory and many other pharmacological effects.In this experiment, it is aimed chiefly at the branches, the leaves, the fruit. Exploring extraction method of the highest extraction rate of resveratrol and lower costs, we choose three different extraction methods such as reflux extraction, ultrasonic extraction and alkali extraction to research by analysis of orthogonal experiments. On the basis of optimization in reflux extraction by response surface method, we attain the optimal extraction approach; Finally we find the difference by extracting resveratrol content in the branches, leaves and fruits of the same grape variety at different growth stages of different organs. The results showed that:1. Resveratrol is extracted in alkali extraction, and inspected the effect of four factors (extraction temperature, extraction time, pH, extraction times) to do the single factor experiments. In analysis of orthogonal experiments, for the sodium hydroxide lye extractant, extraction 3 times, and inspected the effect of three factors (extraction time, extraction temperature, pH) of grape branches to solvent on resveratrol extraction rate in the branches of grape, the optimal technological conditions are as follow: the pH value is 11, extraction temperature is 40℃, extraction time is 2 hours, the number of extraction reach the highest rate 50.04μg/g.In analysis of orthogonal experiments, resveratrol is extracted in ultrasonic extraction for 3 times using the ethyl acetate extractant, and inspected the effect of three factors (extraction time, extraction temperature, the ratio between solvent and dreg) to solvent on resveratrol extraction rate in the branches of grape, the optimal technological conditions are as follow: the ratio of grape branches to ethyl acetate 1:20, extraction temperature is 60℃, extraction time is 30 minutes, the highest rate of extraction of resveratrol reach up to 71.75μg/g.The effect of five factors on resveratrol contents (extraction solvent, extraction time, extraction temperature, solid-liquid ratio, extraction times) in resveratrol by reflux extraction were studied to do the single factor experiments, respectively. Resveratrol is extracted in reflux extraction for the ethyl acetate extractant 3 times.In analysis of orthogonal experiments, and inspected the effect of three factors (extraction time, extraction temperature, the ratio between solvent and dreg) of grape branches to solvent on resveratrol extraction rate in the branches of grape, the optimal technological conditions are as follow: the ratio of grape branches to ethyl acetate 1:30, extraction temperature is 70℃, extraction time is 7 hours, the number of resveratrol is 63.68μg/g in the highest extraction rate.Three extraction method is compared, ultrasonic extraction is more superior than reflux extraction and alkali extraction for its highest extraction rate and stable characteristic, followed by reflux extraction, alkali extraction process the lowest extraction rate.2. Based on the single-factor experiments and the principle of Box-Behnken experiment design, extraction temperature, extraction time and the ratio between solvent and dreg were chosen to be the there factors. We used response surface design which was selected there factors and there levels to optimize the extraction condition of trans-resveratrol from grape branches. The results showed that the there factors had noticeable correlation with extraction content and that the optimization extraction condition was that temperature was 65℃, 6 hours, the ratio 28 mL/g. On the condition of this, the theory content was 106.76μg/g.3. By analysis of high performance liquid chromatography (HPLC), resveratrol content in different periods, different tissues such as stems (the four-year stem, the one-year stem, young shoots), leaves (young leaves, old leaves, mature leaves), fruit etc were detected. The results showed that: The content of resveratrol changed significantly in different grape tissues, however the general presentation is significantly: Stems> leaves> stems> fruit> fruit seeds; the four-year stems> the one-year stems> young shoots, old leaves> mature leaves> young leaves.The average content of leaves reach up to 139.3μg/g.