發(fā)布時間：2019-04-09 12:02

【摘要】：異硫氰酸酯(ITCs)是硫代葡萄糖苷(GLS)在植物內(nèi)源芥子酶作用下的水解產(chǎn)物,主要存在于十字花科蕓苔屬植物中,作為天然的抗癌、抑菌活性物質(zhì)備受關(guān)注。近年來,在番木瓜籽中也發(fā)現(xiàn)含有一定量的硫代葡萄糖苷類物質(zhì),本研究以番木瓜籽為原料,研究了芐基硫代葡萄糖苷的酶解工藝,異硫氰酸芐酯的制備工藝,并對提取物進行了包埋。通過氣質(zhì)聯(lián)用分析推斷出番木瓜籽中只含有一種硫代葡萄糖苷,即芐基硫代葡萄糖苷：從結(jié)果還可以看出,芐基硫代葡萄糖苷的酶解產(chǎn)物除了異硫氰酸芐酯,還有少量的異氰酸芐酯、芐基腈、硫氰酸芐酯。在單因素試驗的基礎(chǔ)上進行Box-Behnken試驗設(shè)計及響應(yīng)面分析,得出芐基硫代葡萄糖的最佳酶解條件為：原料粒徑≥100目,料液比1：20 w/v、酶解緩沖液pH 4.8、酶解時間40 min、酶解溫度27℃,此時芐基硫代葡萄糖苷酶解率為94.0%,異硫氰酸芐酯得率為1.35%。通過比較有機溶劑萃取、水蒸汽蒸餾、同時蒸餾萃取三種提取方法,選取同時蒸餾萃取法作為提取方法,提取條件為：二氯甲烷為萃取劑,萃取時間為2 h。粗提物中異硫氰酸芐酯的分離純化采用硅膠柱層析法,粗提物通過柱層析后純度由87.8%提高到95.0%。對異硫氰酸芐酯的包埋工藝進行了研究,最佳的包埋工藝為芯材比0.5、包埋溫度40℃、包埋時間3 h。通過不同的方法對包埋前后異硫氰酸芐酯的特性進行了研究。相溶解曲線顯示,經(jīng)過包埋后異硫氰酸芐酯的溶解度得到了一定程度的提高；通過熱重分析可以看出,包埋后異硫氰酸芐酯的熱穩(wěn)定性得到了提升；X射線衍射圖譜顯示包埋后β-環(huán)糊精的晶體結(jié)構(gòu)發(fā)生了明顯改變,通過掃描電鏡觀察到的晶體結(jié)構(gòu)也有明顯區(qū)別,通過激光光散射儀測得的粒徑結(jié)果顯示,包埋物的粒徑比為包埋前環(huán)糊精的粒徑大,紅外光譜和核磁共振結(jié)果可用于預(yù)測包埋物的分子結(jié)構(gòu),通過綜合分析認為,異硫氰酸芐酯分子結(jié)構(gòu)上的苯環(huán)可能部分或者完全進入到環(huán)糊精的空腔內(nèi),而-N=C=S基團可能被β-環(huán)糊精部分包埋。本課題通過對番木瓜籽中芐基硫代葡萄糖苷酶解條件進行研究,實現(xiàn)了異硫氰酸芐酯的提取、分離、純化和包埋,獲得了異硫氰酸芐酯包埋物,為提高番木瓜籽的附加值,研究番木瓜籽中異硫氰酸芐酯的功能性奠定基礎(chǔ)。
[Abstract]:Isothiocyanate (ITCs) is the hydrolyzed product of glucosinolate (GLS) under the action of endogenous mustard enzymes in plants. It mainly exists in brassica plants of Cruciferae family. As a natural anticancer substance, its antibacterial activity has attracted much attention. In recent years, a certain amount of glucosinolates was found in papaya seeds. In this study, the enzymatic hydrolysis of benzylthioglucosides and the preparation of benzyl isothiocyanate were studied using papaya seeds as raw materials. And the extract was buried. It was concluded by GC-MS that there was only one glucosinolate in papaya seeds, that is, benzylthioglucosides. The results also showed that the enzymatic hydrolysate of benzylthioglucosides except benzyl isothiocyanate was found to contain only one kind of glucosinolates, that is, benzyl thioglycosides. There are also a small amount of benzyl isocyanate, benzyl nitrile, benzyl thiocyanate. On the basis of single factor test, Box-Behnken test design and response surface analysis were carried out. The optimum conditions for enzymatic hydrolysis of benzylthioglucose were obtained as follows: raw material diameter 鈮，

本文編號：2455164