Grape seed extract is a kind of polyphenols extracted from grape seeds. It is mainly composed of procyanidins, catechins, epicatechins, gallic acid, epicatechin gallate and other polyphenols.
characteristic
Antioxidant capacity
Grape seed extract is a pure natural substance. It is one of the most efficient antioxidants from plant sources. The test shows that its antioxidant effect is 30 ~ 50 times that of vitamin C and vitamin E.
activity
Procyanidins have strong activity and can inhibit carcinogens in cigarettes. Their ability to capture free radicals in aqueous phase is 2 ~ 7 times higher than that of general antioxidants, such as α- The activity of tocopherol is more than twice as high.
extract
It was found that among many plant tissues, the content of proanthocyanidins in grape seed and pine bark extract was the highest, and the main methods of extracting Proanthocyanidins from grape seed were solvent extraction, microwave extraction, ultrasonic extraction and supercritical CO2 extraction. Grape seed proanthocyanidins extract contains many impurities, which need further purification to improve the purity of proanthocyanidins. The commonly used purification methods include solvent extraction, membrane filtration and chromatography.
Ethanol concentration had the most significant effect on the extraction rate of grape seed proanthocyanidins, and the extraction time and temperature had no significant effect on the extraction rate of grape seed proanthocyanidins. The optimum extraction parameters were as follows: ethanol concentration 70%, extraction time 120 min, solid-liquid ratio 1:20.
The static adsorption experiment shows that the highest adsorption rate of hpd-700 for proanthocyanidins is 82.85%, followed by da201, which is 82.68%. There is little difference. Moreover, the adsorption capacity of these two resins for proanthocyanidins is also the same. In the desorption test, da201 resin has the highest desorption rate of procyanidins, which is 60.58%, while hpd-700 has only 50.83%. Combined with adsorption and desorption experiments, da210 resin was determined to be the best adsorption resin for the separation of procyanidins.
Through process optimization, when the concentration of proanthocyanidins is 0.15mg/ml, the flow rate is 1ml / min, 70% ethanol solution is used as eluent, the flow rate is 1ml / min, and the amount of eluent is 5bv, the extract of grape seed proanthocyanidins can be preliminarily purified.