利用酵素水解明膠及卵白蛋白製備抗高血壓胜?

Tunghai University Institutional Repository > 農學院 > 食品科學系所 > 碩士論文 > Item 310901/10612

Please use this identifier to cite or link to this item: http://140.128.103.80:8080/handle/310901/10612

Title:	利用酵素水解明膠及卵白蛋白製備抗高血壓胜?
Other Titles:	Production of angiotensin I - converting enzyme inhibitory peptides from gelatin and ovalbumin by protease
Authors:	翁千惠 Weng, Chien-Hui
Contributors:	蔡正宗 Tsai, Tsun - Chung 東海大學食品科學系
Keywords:	血管收縮素轉化?;明膠;卵白蛋白;ACE抑制劑;胜?;酵素水解產物 ACE;gelatin;ovalbumin;ACE inhibitor;peptide;enzymatic hydrolysate
Date:	2004
Issue Date:	2011-07-26T03:56:39Z (UTC)
Abstract:	第一部分利用酵素水解明膠製備抗高血壓胜? 養豬是台灣主要的畜產事業，其副產物之豬皮產量多，善加利用，可提高經濟效益，也可增加飼主收入。從豬皮萃取的明膠(Gelatin)應用於食品、醫藥、工業等方面。但用量有限，經濟價值有待提升。Gelatin的胺基酸序列單純，含有多重再現之規則排序(Pro — X — Gly -Pro )，本研究利用合適的酵素水解可獲得抗高血壓抑制胜?，將之應用於添加飲料或食物中，因而製備具有保健效果之食物。初步選用五種蛋白酵素：collagenase、trypsin、chymotrypsin、esperase和alcalase水解明膠反應，在初期二小時內，trypsin的效果優於其他蛋白酵素；在四到八小時之水解反應，則esperase最好，其次是collagenase。以時間及價格考量下，選用trypsin及esperase作進一步研究。在不同esperase濃度及水解時間的動力學研究中，添加E / S = 0.2% (1/500 w/w) esperase用量及水解是最經濟及省時的。選用的條件為2 %明膠(pH 8.0)先在37 ºC下以0.2 % Trypsin水解1 hr，再以60 ºC添加0.2 % esperase水解2 hr。在此條件下的水解產物具有60 % ACE抑制作用。水解液顏色淡黃，總生菌數為TFTC，無苦味而有淡淡異味，其冷凍乾燥後的粉末呈淡黃色。L、a、b值為96.58、1.79及5.27。經超過濾處理的分區產物，MWCF 3000其抑制率為77.3 %。水解液經胃、胰液?之消化作用後，抑制活性可提高至62.7及74.8 %。第二部分利用酵素水解卵白蛋白製備抗高血壓胜? 雞蛋的營養價值高，所含的蛋白質擁有平衡胺基酸組成，故常被用來當做蛋白質品質評估的標準品。因為蛋黃含有較高的膽固醇，因此全蛋的食用大受限制。若將蛋白加工製成機能性食品，如：雞精、營養補充品等，將可提高雞蛋的附加價值及促進銷售量，並提高飼主收入。本研究的主要目的是篩選合適的蛋白質酵素水解雞蛋卵白蛋白(ovalbumin)，得到之水解液再經過連續的超過濾(ultra — filtration)，製備出具有抗高血壓效果的小分子胜?片段，將之添加在食品中，除了作為保健食品外，另可提升副產品的經濟效益。實驗結果顯示：最佳的水解條件為使用E / S = 0.2 % (1 / 500 w / w) thermolysin水解1 % ovalbumin，在60℃，pH 8，反應4 hr中，其IC50 為33 μg / ml，產率為87 %。水解液色澤呈淺黃色。L、a及b值為99.27、— 0.94 及5.82。無微生物生長。以1 % (w/v)添加入牛乳中，經官能評估結果無苦味，整體接受度高。水解液對胃蛋白?有良好安定性，再經胰液?之消化作用，能提高其抑制活性(約104 %)。而水解液經過超過濾不同分子量膜限值分離(MWCF 10000, 3000及1000)，IC50分別為58、43、25 及14 μg / ml。 Part I Production of angiotensin I—converting enzyme inhibitory peptides from gelatin by protease Growing pigs is a major animal industry in Taiwan and the yield of porcine skins is excess. If we take good advantage of them, breeders will increase incomes and get high economy value. The gelatins from porcine skins have been used in food, medicine and industry. However its applicable quantity and value is still contains needed to be promoted. The amino acid sequence of gelatin is simple and regular repetition sequences (Pro — x — Gly — Pro). The objective of this investigation is to prepare Angiotensin I — converting enzyme inhibitory peptide hydrolysate from gelatin by using suitable proteases. And the hydrolysates could be added to drink or food as health food. Five commercial proteases have been tested in studying production of ACE inhibitory peptide from porcine skin gelatin. Trypsin showed much better than others in production of ACE inhibitor in first two-hour hydrolysis and esperase turned out to be the best one and collagenase next in following four — eight hours hydrolysis. Base on the cost of enzyme and time consumption in hydrolysis, trypsin and esperase were chose in production of ACE inhibitory peptide. Results of kinetic study indicated that optimal condition to hydrolyze 2 % gelatin solution (pH 8) was digested first by 0.2 % trypsin for 1hr at 37 ºC, then 0.2 % esperase for 2 hr at 60 ºC to have inhibition activity around 60 %. The final hydrolysate is pale yellow in color, blend in taste, and no microbial contamination. L , a , and b of hydrolysate were found to be 96.58 , 1.79 and 5.27 respectively. Freeze — dried powder is pale yellow in color. Further fractionation of hydrolysate by ultra-filtration, ACE inhibition of fractions of MWCF 3000 was found to be 77 % ACE inhibition. Inhibition of activity hydrolysate was stable to pepsin digestion, and increased by pancreatin digestion. Part II Production of angiotensin I-converting enzyme inhibitory peptides from ovalbumin by protease Eggs are high nutritive food with balance amino acids. Because of high cholesterol content, eating whole eggs is limited. The objective of this work is to prepare Angiotensin I — converting enzyme inhibitory peptide from egg white by suitable proteases. And the hydrolysates can be added on drink or food to promote its economy benefit. The experiment result showed the optimal condition for hydrolysis was that 1 % ovalbumin solution (pH 8) was digested by 0.2 % thermolysin for 4 hr at 60 ºC to have IC50 value 33 μg / ml (yield of 87 %). IC50 of hydrolysate filtrate from further fractionation with MW cut — off 1000, 3000, and 1000 were found to be 58、43、25 and 14 μg/ml respectively. Hydrolysate is pale yellow in color and bland in taste with high acceptability. Inhibition activity of hydrolysate was found stable to pepsin digestion, and pancreatin digestion. The two substrates are prepared ACEI. And the result shows that ACEI from ovalbumin is better.
Appears in Collections:	[食品科學系所] 碩士論文

Files in This Item:

There are no files associated with this item.

Loading...