Study On Extraction And Isolation Of Alliin From Garlic And Its Recrystallization

Garlic since ancient times has the function of medicine and food,"Herbal Supplements" and the Ming Dynasty Li Shizhen "Compendium of Materia Medica" on the medicinal properties of garlic have a detailed record.Modern pharmacological studies have found that garlic has significant efficacy in the prevention and treatment of cardiovascular diseases,anti-inflammatory,anti-microbial and anti-tumor.Further research found that the main active substance is alliin in garlic.Alliin in garlic is a relatively stable compound,alliin and garlic enzyme in the case of broken garlic tissue,triggering a series of enzymatic reactions,the formation of sulfur compounds such as allicin.The latter is very unstable at room temperature degradation of a variety of non-active substances.In this paper,starting from fresh garlic,the process of obtaining a large number of high-purity alliin products with high efficiency was studied in order to provide reference for industrialized production.First of all,the HPLC method for the determination of alliin was revised to confirm the experimental HPLC conditions: the mobile phase of acetonitrile: water(55:45),detected at 210 nm UV absorption wavelength column Temperature control at room temperature,flow rate of 1.0mL/min,injection volume of 20μL.A detailed examination of alliin extraction process conditions.The first aspect is about the experimental conditions of garlic pretreatment;the second is the extraction of alliin conditions.The effects of inactivation power and time of inactivation of alliinase on the inactivation by microwave inactivation were investigated by orthogonal test.The optimal conditions for 60 s inoculation under medium fire condition were determined.The best extracting condition of alliin was obtained by single factor experiment and response surface method using 20% ethanol as extraction solvent supplemented by ultrasonic extraction technology: the ratio of solid to liquid was 1:4.5,the ultrasonic power was 67 W and the ultrasonic time was 1.7 h Through the verification of the process,the highest yield of alliin was 91.8%.Isolation and purification of alliin were studied.The analytical column was used to separate and purify alliin,and the conditions for the separation of alliin using 732 strongly acidic cation resin were investigated.Finally,the following process parameters were determined: the sample concentration was controlled at about 3mg/ml,the sample flow rate was 1.0 BV/h,the adsorption rate of alliin could reach 821.3mg/100 g under this condition;,The eluent concentration was 0.30mol/L,the eluent flow rate was 1.0 BV/ h.Through the process validation,the purity of alliin can reach 64.3% under this separation condition.At the isoelectric point adjustment combined with crystallization and recrystallization of alliin purification.The effect of crystallization temperature and solvent on alliin crystallization was investigated.Alliin was found to crystallize in 60% ethanol at 40° C and allowed to stand for a certain period of time.This process was repeated three times to obtain a purified alliin product with a purity of over 92%.The alliin final products were analyzed by high performance liquid chromatography,infrared spectroscopy and mass spectrometry.The results are consistent that: Alliin obtained by the above process in the structure consistent with the standard.