Extraction And HPLC Determination Of Procyanidins In The Fruits Of Different Plants

Proanthocyanidins are a large class of phenolic compounds existing widely in plantkingdoms, which is an effective natural antioxidants and free radical scavenger. Furthermore,proanthocyanidins, which are an effect in anti-inflammatory, anti-aging, prevention ofatherosclerosis, anti-cancer changes, immune activity, prevention of cardiovascular diseasesand other functions, has great development and application value.In the first part, microwave-assisted extraction (MAE), Soxhlet extraction, ultrasonicextraction (UE) were used and combined with HPLC for the extraction, separation anddetermination of epicatechin, catechin and procyanidin B2in grape seeds. In the extractionexperiments, single factor experiment is used to determine the initial conditions for theextraction and then further optimize by use of orthogonal experiment, The HPLC method isused for qualitative and quantitative analysis of the target analytes from grape seeds. TheHPLC method was verified for parameters including reproducibility, limit of detection (LOD)and linearity. Finally, we compared the three kinds of extraction method to extract the targetanalyte, MAE method is the best.In the second part, the technology of soxhlet extraction of the epicatechin, catechin andprocyanidin B2from grape seeds, acorn and pomegranate seeds were studied. Theconcentration of solvent extraction, extraction time, solid-liquid ratio and extractiontemperature were investigated on the extraction of target analytes effect. After the processesof handling samples and purification by the solid phase extraction technology, the sampleswere detected by the high-performance liquid chromatography. Finally, the content of thetarget analyte in the fruits of three plants were compared. The results showed that the optimalextraction conditions were:60%ethanol solution as extraction solvent, extraction time of40min, extraction temperature of70℃, solid/liquid ratio of1:40g/mL. Under the sameextraction conditions, the highest levels of epicatechin and procyanidin B2in grape seedwere21.88mg/g and3.14mg/g, and the amount of catechin content of Pomegranate seedscan reach to10.86mg/g.