Study On The Extraction And Separation Of Procyanidins From Episperm Of Tea Seeds

Procyanidins is oligomers and polymers of flavanol units which is widely distributed throughout the plant kingdom.It is one of highly efficient,low toxic and bioactive natural products,which has many kinds of pharmacological activities such as anti-oxidation, anti-tumor,and cholesterol reduction.The aim of this study on the extraction and separation of PC from tea seed is to fully develop tea seed episperm,extend the extraction resource for PC and improve the utilization ratio and the extra-value of agriculture product and by-product.Additionally,it will offer theoretical foundation to effectively utilize and comprehensively develop tea seed episperm.In order to seek plant resources with richer content PC,two methods were applied for selecting different plants by detection of PC content in this paper.As a result,it was showed that:PC were richer in these plants such as red skin of the peanut,fruit of metasequoia,fruit of arborvitae,tea seed episperm and Zanthoxylum bungeanum,whose content could reach above 5.79%,while the PC content was relatively lower in other plants.This work was mainly focused on the study of PC extraction from tea seed episperm and it was analyzed by one factor in terms of grind degree,extraction time,ethanol concentration,extraction time,ratio of material to liquid and extraction times.The result indicated that the extraction rate of PC was increasing gradually with heavier smash level of tea seed episperm and it was reached maximal with the condition of 80～100 meshes, while the extraction rate was going down with over smashed degree.Similarly,the extraction rate was going up with time increase during 30 min and then it was stable.And the extraction rate was also increasing by use of more ethanol,the maximal rate was reached at the point of 60%ethanol and then it was going down.The same thing showed in the condition of temperature and 45℃showed the best effect and then went down.The smaller of ratio of material to liquid(Ratio of M/L),there were the better for the extraction rate of PC.The ratio of M/L is lower than 1/10,the speed of extraction rate increased quickly while it was showed reverse effect when the ratio is more than 1/10.Totally,twice for the extraction is the best choice.In order to extract PC effectively,quadratic general rotary unitized design was applied to study the PC extraction parameter of tea seed episperm.As a result,the equation was obtained as follow:and obtained a Standard Curve:(?)=8.179+0.155X₁+0.177X₂+0.160X₃+ 0.154X₄-0.150X₁²-0.174X₂²+0.099X₃²-0.002X₄²+0.084X₁X₃+0.151X₂X₄;The result showed that the effect of extraction time,ethanol concentration,extraction temperature and thee ratio of M/L on the PC extraction was significant and addressed as X₂＞X₃＞X₁＞₄.The optimial scheme after optimize simulization was as follows:28rain of extracting time,60% of ethanol concentration,55℃of temperature,1:6 of the ratio of material to liquid,and the highest PC extraction ratio from tea seed eptsperm was 96.80rag/g,And the actual extraction rate was 95.30 mg/g which was proved effectively by later amplificatory experiment.In order to obtain relatively purified PC,the crude PC was separated by columns in this paper.We employed HPD100,HPD200A,HPD400A,HPD700,HPD800 macroporous resin and 30～60 meshes polyamide as the fillers.In the following experiments,the suitable fillers were tested by static column method.The result showed that 30～60 meshes polyamide,HPD800 and HPD200A had good absorption capacity,but 30～60 meshes polyamide and HPD800 had poor desorption capacity,HPD200A has the biggest desorption capacity,so HPD200A was chose as the column filler to make further separation.We reviewed the factors including sample feeding rate,sample pH,elution rate,pH of elution and elution concentration etc,which influenced the PC absorption and desorption on HPD200A,by the guideline such as absorption capacity,absorption ratio,absorption time,desorption ratio and desorption time in stationary and dynamic experiments,The result showed that the detection index underneath dynamic condition fitted for the change of theoretical rule as the review factor changed in grads.Fully considering influence factors and yield ratio,the optimal condition is as follows:column filled with HPD200A (pH5.0),sample loading speed:1.50 ml/min;elution by 20%ethanol(pH7.0) and elution speed:0.50ml/min,after that,elution by 60%ethanol(pH7.0) with 0.50ml/min.The result showed that absorption capacity,ratio and time were 69.12mg/ml,92.86%and 486min, respectively.And the desorpation rates were 28.40%by 20%ethanol which was termed as Sampleâ… and 69.87%by 60%ethanol termed as Sampleâ…¡.The obtained PC was determined by nature and quantity analysis with anthocyanin reaction,UV-scanning and thin layer chromatography.The results showed that Sampleâ… andâ…¡were both PC and their recovery were 15.00 mg/g and 36.90mg/g,purity of them were 97.22%and 76.46%,respectively.Additionally,sampleâ… contained 0.05%D,L-C, 0.35%EGCG and 0.02%theobromine by HPLC while sampleâ…¡contained 0.01%EGCG, 0.02%theobromine and 0.07%caffeine,respectively.