蛋殼膜膠原蛋白之萃取及其水解液機能性之研究

Abstract

本研究之主要目的有兩個，一是建立蛋殼膜膠原蛋白之萃取流程；二是探討不同水解條件對蛋殼膜膠原蛋白粗萃物抗氧化性(antioxidative activity)以及抑制血管緊縮素轉化酵素 （angiotensin converting enzyme; ACE）能力之影響，希望能藉此研究提高蛋殼膜之附加價值，期能增加液蛋工廠之收益。 建立蛋殼膜膠原蛋白萃取流程方面，首先將蛋殼以磨碎機磨碎，再以水和篩網分離蛋殼與蛋殼膜後，將分離好的蛋殼膜以酸萃法（0.5M 醋酸）的方式萃取膠原蛋白，計算膠原蛋白粗萃物萃取率以及進行電泳分析，所獲得之膠原蛋白粗萃物萃取率為14.28%。 蛋殼膜膠原蛋白粗萃物之機能性測試實驗，將蛋殼膜膠原蛋白粗萃物，以四種不同的酵素（鹼性蛋白酵素、中性蛋白酵素、蛋白水解酵素、胰蛋白酵素）、三種不同之水解溫度（50、60、70℃）及三種不同之水解pH值(pH6、7、8)進行水解1~5小時，之後測定各處理組之月太類濃度、抗氧化能力及抑制血管緊縮素轉化酵素能力。 實驗結果得知，在酵素影響上抗氧化力、還原力以是以鹼性蛋白酵素、蛋白分解酵素來進行水解之水解液表現較好，DPPH清除能力及ACE抑制能力是以胰蛋白酵素有較高的效果，但在亞鐵離子螯合能力、超氧陰離子清除能力方面卻是以中性蛋白酵素最佳。 在水解條件之影響上，水解時間越長(1、2、3、4、5小時)、水解溫度越高(50、60、70℃)，會提升水解液的peptide濃度進而提高水解液的機能性，但水解至一定程度則月太類濃度便不會顯著的提升，水解液機能性的提升也會趨於平緩，水解液之酸鹼值(pH6、7、8)對水解液的機能性沒有顯著影響。

Liquid egg factory had produced a lot of eggshell. In fact, collagen type Ⅰ, Ⅴ and Ⅹ have been found in the eggshell membranes ( Wong et al., 1984 ). Collagen is a composed of tropocollagen monomers arranged in overlapping fibrils that are configurated in three non-identical coiled peptide chains. Collagen and associated hydrolysate have desirable characteristics for various industrial applications. For example, they are not hazardous to human health, are capable of water retention on the molecular scale, are essential biological nutrients as can serve as chromatographic carrier particles. They can be used in materials associated with or included in cosmetics, artificial organs, etc. This study had two purposes, one was to establish a process to separate eggshell membranes from eggshell and to extract the collagen from eggshell membranes. Another one was to study the eggshell membranes collagen functional properties in order to increase eggshell membrane’s commercial application. Eggshell are cracked and then washed with water in order to separate eggshell membranes from eggshell and use acetate acid to extracted collagen from eggshell membranes. The yield ratio of collagen extracted from eggshell membranes was 14.28%. In functional test, the collagen was hydrolyzed for 1 - 5 h by four different enzymes of alcalase, neutrase, protease, trypsin. We measure the antioxidative activity and angiotensin converting enzyme (ACE) inhibitory activity of each hydrolysates at different temperature and pH. The results showed that among the four enzymes the sample which hydrolysates digested with alcalase and protease had expressed well on antioxidant ability and reducing ability. The hydrolysates digested with trypsin show the higher scavenging DPPH free radical ability than other enzymes. The Chelating ferrous ion ability and scavenging superoxide anion ability expressed well when hydrolyzed by neutrase. The hydrolysates digested with trypsin revealed a highest ACE inhibitory activity. The antioxidative activity and angiotensin converting enzyme inhibitory activity could be futher enhanced by hydrolysis time (1 - 5 h), hydrolysis temperature (50、60、70℃) and peptide concentraction. However, pH did not affect the antioxidative activity and angiotensin converting enzyme inhibitory activity of the hydrolysates.