Extraction, Purification And Antioxidant Activity Of Total Phenols And Rutin From Buckwheat Straw

Buckwheat is a kind of nutrient-rich food crop,which is regarded as "longevity food,health care products" deeply loved by people.According to the study of buckwheat nutrients known at home and abroad,we know that the content of protein,fat,vitamins and trace elements in buckwheat is higher than that of grain,such as rice,wheat and corn,and they contain other polyphenols and flavonoids that are not found in cereals.The current situation of buckwheat processing industry in China has been hovering in the primary stage of processing,with less processing products,lower total technological content and single processing products,and the value of buckwheat can not be fully utilized.The most important is that during the maturation period,a large amount of buckwheat stalk waste is discarded and incinerated,which results in great pollution and has not been fully utilized.Polyphenol and flavonoid active substances can be extracted from buckwheat straw,which can not meet the demand and has a great development prospect in the market.The polyphenols in buckwheat extracts have a strong antioxidant capacity and have a preventive and therapeutic effect on arteriosclerosis,heart disease,liver disease and other geriatric diseases.Among them,the flavonoid of rutin is the most abundant.It has anti-inflammatory,anti-allergic,diuretic,antispasmodic,antitussive,hypolipidemic,and cardiac acuity effects.It also has good curative effects on the treatment of vascular diseases,diabetes,and obesity.So this research from stems,leaves,flowers,fruits and waste straw multi-level comprehensive processing and utilization of all,through the process optimization and technical renovation to buckwheat by-products make full use of raw materials,can improve the enterprise scale,promote the buckwheat by-products processing industry value maximization.This experiment mainly by studying the buckwheat polyphenol in straw,rutin extraction process and macroporous resin purification process,get the best extraction and purification technology of mass production for the factory to provide theoretical support;The extraction of polyphenol and rutin from buckwheat straw was carried out with the best extraction process,and purification of the extract was carried out with the best purification process,and the final purification was obtained.At the same time,the components were identified by high performance liquid chromatography analyzer.Finally studying extraction and purification of total reducing power,remove DPPH radical,hydroxyl free radical,ABTS radical and superoxide anion,for its health care function and provide a scientific basis for regulating physiological function.The main results are as follows:1.Obtain the optimum extraction process through single factor test and orthogonal test:take buckwheat stalk as raw material,smash 60 mesh sieve,solvent acetone 50%,solid-liquid ratio 1:25,extraction temperature 55℃,ultrasound-assisted The extraction power was 250 w,the extraction time was 15 min,and extraction was carried out twice.The extracts were combined and rotary evaporation and vacuum freeze-drying were used to obtain the crude extract.This process route was economical,practical and feasible,with the highest yield of total phenol and rutin.2.Selecting the adsorption of macroporous resin to select the best adsorption resin,and study the adsorption and desorption conditions and adsorption kinetics to achieve the separation and purification effect.Optimal static adsorption and desorption conditions:XDA-6 macroporous resin,extract concentration 400 mg/L,pH 4.54,shaking rate 120 r/min,adsorption 8 h,60%ethanol solution as eluent,elution Time is 4h;Optimum dynamic adsorption and desorption conditions:XDA-6 macroporous resin was wet packed,and the extraction solution concentration was adjusted to 800 mg/L,the pH was about 4.54,and the extraction was performed at a flow rate of 1 mL/min(3 BV/h).100 mL(5BV)reaches saturation.Then apply 2BV of distilled water to rinse the resin,and apply 6V ethanol stripping solution 7BV at a flow rate of 1mL/min(3BV/h).Collect the desorption solution for each VB,remove the first column volume and the last column volume.The volumes were combined and rotary evaporation and vacuum freeze-drying afforded the purified material.3.High performance liquid chromatograph(HPLC)analysis results showed that after extraction and purification of the target product in the main ingredients of rutin and quercetin,still haunted by detecting gallic acid,catechin,kaempferol and etc.4.Test the coarse extract and purification of all show different degree of oxidation resistance,with removal of DPPH free radical,hydroxyl free radical,ABTS radical and superoxide anion ability,but the ability to remove strength and half inhibitory concentration(IC50)are differences.Using VC as the positive control group,it can better and better express its antioxidant effect.