Study On The Extraction And Purification And Antioxidant Activitiy Of Quercetin From The Stem Bark Of Actinidia Arguta

Actinidia arguta belongs to the Actinidiaceae, Actinidia Lindl. which is a kind of perennial defoliation vineplant. All parts of Actinidia arguta have medical value, the root of it is known as Tengligen by traditional Chinese medicine, which can against the spread of cancer cells, as well as relief nasopharynx. The stem of Actinidia arguta has the function of enhancing antioxidase activity, scavenging free radical, anti-aging and biological membrane protecting. Moreover, the delicious and nutrient-rich fruit of Actinidia arguta also can be used as medicine to enhance human body.Quercetin is a kind of chemical compound, which is widely distributing in the leaf. stem and fruit of plants. Quercetin has various benefits for human health, such as against cancer, tumor and protect cardiovascular.In the growth process of Actinidia arguta, huge amount of branch had been cut and abandoned, which lead to the waste of Actinidia arguta’s biological value. Therefore, to avoid the waste of wild resource, the effective constituents such as quercetin in branch of Actinidia arguta need be deeply analyzing and extracting to drive the development of Actinidia arguta industry and gain profits.There are currently no academic researches with respect to extracting quercetin from the Actinidia arguta. Therefore, this article focus on the quercetin’s extraction, depuration and antioxidant activities through the bark of Actinidia arguta and got the following conclusion:With quercetin standard curve as the reference value, stem bark is the most quercetin abundant part (0.6045 mg/g) in Actinidia arguta, which is 2.4 times larger than stem.3.5 times than root. Hence, to make rational use of Actinidia arguta resource, stem bark is the best place to extracting quercetin.The ultrasonic-assisted extraction method had been used during the experiment, the result explores the optimum quercetin extraction process. The specifically parameter is 300 W ultrasonic power,1:80 material liquid ratio,78 ℃ bath temperature,58% ethanol concentration and 20 mins ultrasound. Under this condition. the final extraction ratio of quercetin in the experiment is 1.0499 mg/g, which is roughly in line with the model prediction. The single factor experiment demonstrates that bath temperature, ethanol concentration and ultrasound are the significant influence factors during the quercetin extraction experiment. According to the analysis of response surface experiment, the influence value of the above three elements is bath temperature> ethanol concentration> ultrasound. Besides, ultrasound in experiment illustrates strong interaction effect with bath temperature and ethanol concentration, in contrast, there is no obvious interaction effect between bath temperature and ethanol concentration.By considering the adsorption and desorption ratio between six pattern of microporous resin (S-8, AB-8, X-5, D101, D1400 and D4020) the research shows S-8 have the best adsorption capacity but weak in the desorption part, AB-8 comprehensively balance the adsorption and desorption ratio and could be suitable to depurating quercetin. The separation and purification experiment by using AB-8 illustrates that the concentration of quercetin sample liquid in Actinidia arguta stem is 0.4 mg/mL (pH 4.45),3 BV sampling amount, flow rate 1.5 mL/min, eluent strength is 80% ethyl alcohol, flow rate 1.5 mL/min with volume 3 BV. According to the above technological conditions, the purity of quercetin in Actinidia arguta stem bark is 41.3%.After the DPPH free radical, reducing power determination, hydroxyl radical scavenging, superoxide anion free radical determination and inhibiting activity on liposome peroxidation determination, it could be easily analysis that the scavenging ability of quercetin in Actinidia arguta stem bark is better than vitamin C (with IC50 index 16.47 ug/mL and 0.78 mg/mL respectively). In the respect of hydroxyl radical scavenging and superoxide anion free radical, the usage of vitamin C is much less than quercetin in Actinidia arguta stem IC50 index 4.64 mg/mL and 2.72 mg/mL to be precise. In terms of the reducing force, vitamin C illustrates slightly strong ability when compare with quercetin in Actinidia arguta stem bark.