發(fā)布時(shí)間：2018-09-19 11:25

【摘要】：鋅對(duì)人體健康非常重要,鋅缺乏導(dǎo)致多種疾病,而酪蛋白磷酸肽是一種具有促進(jìn)鋅離子吸收的活性多肽,可以螯合成酪蛋白磷酸肽螯合鋅,開(kāi)發(fā)作為一種補(bǔ)鋅劑。目前市場(chǎng)多見(jiàn)的補(bǔ)鋅制劑如硫酸鋅等老一代無(wú)機(jī)鋅鹽,相比酪蛋白磷酸肽螯合鋅等新一代多肽螯合補(bǔ)鋅劑,雖然成本低,來(lái)源易獲得,但刺激度高,毒性大,生物利用度低,酪蛋白磷酸肽螯合鋅在活性和安全性均優(yōu)于前一代鋅補(bǔ)劑。因此本研究以具有鋅螯合活性的酪蛋白磷酸肽(CPPs)為研究對(duì)象,可開(kāi)發(fā)作為新一代有機(jī)鋅補(bǔ)劑的材料。以堿性蛋白酶酶解得到的酪蛋白磷酸肽為原料,經(jīng)Q Sepharose FF陰離子交換色譜與RP-HPLC(反相高效色譜)色譜法兩步分離后得到的高鋅螯合活性的CPPs,在pH 7.0,CPPs與鋅源物料比4:1,60℃,80min反應(yīng)條件下進(jìn)行螯合。經(jīng)SDS-PAGE電泳檢測(cè),該肽段分子量10k Da,螯合活性達(dá)88.68μg/mg,與純化前粗肽相比,多肽含量提高3.6倍,鋅結(jié)合量提高了10倍。以上述兩部純化后得到的高鋅螯合活性的酪蛋白磷酸肽為原料,對(duì)比螯合前后,經(jīng)氨基酸組成分析、紫外光譜、紅外光譜以及固體核磁共振13C譜、1H譜、31P譜解析,結(jié)果表明,螯合前后CPPs的結(jié)構(gòu)及氨基酸組成發(fā)生了明顯變化,其中的磷酸基團(tuán)參與了螯合,其主要結(jié)合位點(diǎn)是-COOH、-NH2及P-OH中的-OH。在體外模擬胃腸道消化環(huán)境,考察酪蛋白磷酸肽螯合鋅的生物利用度(溶解度以及透析度),對(duì)比葡萄糖酸鋅和ZnSO4的生物利用度,酪蛋白磷酸肽螯合鋅則高于其兩者;酪蛋白磷酸肽螯合鋅釋放Zn2+的速率慢于Zn SO4和葡萄糖酸鋅,能減少對(duì)胃的刺激;膳食纖維和Fe2+過(guò)量的存在會(huì)影響酪蛋白磷酸肽螯合鋅的生物利用度。酪蛋白磷酸肽螯合鋅在模擬胃腸道消化過(guò)程中具有生物穩(wěn)定性,可以作為可靠的高生物利用度的鋅補(bǔ)劑。
[Abstract]:Zinc is very important to human health. Zinc deficiency leads to many diseases. Casein phosphopeptide is a kind of active peptide which can promote the absorption of zinc ion. It can be chelated to zinc casein phosphopeptide chelate and developed as a zinc supplement agent. Compared with the new generation of polypeptide chelating zinc reagents, such as zinc sulfate and zinc sulfate, the most common zinc supplements in the market are of low cost and easy to obtain, but they have high stimulation degree, high toxicity and low bioavailability. The activity and safety of casein phosphopeptide chelate zinc were better than that of previous zinc supplement. Therefore, in this study, casein phosphopeptide (CPPs) with zinc chelating activity can be used as a new generation of organic zinc supplement material. Casein phosphopeptide obtained by enzymatic hydrolysis of alkaline protease was used as raw material. Q Sepharose FF anion exchange chromatography (Q Sepharose FF) and RP-HPLC (reversed-phase high performance chromatography) chromatography were used to chelate high zinc chelating CPPs, under the reaction conditions of pH 7.0% and zinc source material ratio of 4: 1 ~ 60 鈩，

本文編號(hào)：2249996