本文選題：海藻　切入點(diǎn)：脂肪酸　出處：《溫州大學(xué)》2016年碩士論文

【摘要】：海藻中因含有不飽和脂肪酸如我們?nèi)梭w必需的DHA、EPA等不飽和脂肪酸而具有營(yíng)養(yǎng)價(jià)值和醫(yī)藥方面的研究?jī)r(jià)值。快速、靈敏、準(zhǔn)確的測(cè)定海藻中脂肪酸的分析方法,對(duì)于深入研究脂肪酸與海藻生物活性之間的關(guān)系具有重大意義。本論文旨在通過(guò)比較不同衍生化試劑與脂肪酸衍生化反應(yīng),選擇最佳衍生化試劑,對(duì)脂肪酸結(jié)構(gòu)進(jìn)行修飾提高質(zhì)譜響應(yīng)信號(hào),建立一種快速、靈敏、準(zhǔn)確的衍生化高效液相色譜-串聯(lián)質(zhì)譜法,并應(yīng)用于海藻中脂肪酸含量的測(cè)定。主要內(nèi)容如下:第一部分研究建立了海藻中總脂質(zhì)的提取方法。通過(guò)多種不同的提取方法如溶劑浸提法、超聲波提取法、索氏提取法、改進(jìn)的Folch法對(duì)海藻粉末進(jìn)行總脂質(zhì)的提取,最終選擇以改進(jìn)的Folch法提取海藻中的總脂質(zhì)。采用單因素實(shí)驗(yàn)選取液料比、提取功率、提取溫度和提取時(shí)間,得到最佳工藝條件為:以二氯甲烷-甲醇為提取溶劑、提取時(shí)間為90 min、最佳溫度為50℃、最佳功率為80 W。羊棲菜中總脂質(zhì)提取率為5.7%。第二部分建立了柱前衍生高效液相色譜串聯(lián)質(zhì)譜測(cè)定脂肪酸的方法。以N-(2-羥乙基)-吡咯烷、N,N-二甲基乙二胺、N,N-二甲基乙醇胺為衍生試劑對(duì)脂肪酸進(jìn)行衍生,優(yōu)化了衍生條件。通過(guò)衍生條件、衍生劑價(jià)格等因素的比較,最終確定N,N-二甲基乙二胺為最佳衍生劑,由于N,N-二甲基乙二胺含有氮原子,氮原子是負(fù)電性,通過(guò)碘甲烷反應(yīng)形成季銨鹽,大大提高了質(zhì)譜的離子化效率。在本章中同時(shí)比較了衍生化后的脂肪酸和未衍生化的脂肪酸的檢測(cè)限,結(jié)果表明,三種飽和脂肪酸和五種不飽和脂肪酸衍生后的質(zhì)譜檢測(cè)靈敏度提高了100倍以上。并且N,N-二甲基乙二胺中N,N-二甲基官能團(tuán)是水溶性基團(tuán),與脂肪酸反應(yīng),使其水溶性提高,因而縮短脂肪酸衍生物在液相柱中的保留時(shí)間,節(jié)省了檢測(cè)時(shí)間。第三部分采用高效液相色譜串聯(lián)質(zhì)譜法測(cè)定海藻中的脂肪酸。結(jié)果表明:二十二碳六烯酸在三種海藻中幾乎不存在,二十碳五烯酸(20:5)和α-亞麻油酸在海藻中含量較多,在海藻中有些脂肪酸存在同分異構(gòu)體現(xiàn)象,在三種海藻中棕櫚酸含量均較高。由于采用二級(jí)質(zhì)譜對(duì)脂肪酸進(jìn)行定量分析,即使未完全分離仍能準(zhǔn)確測(cè)定,因此提高了方法的選擇性,縮短了檢測(cè)時(shí)間,為海藻中脂肪酸的測(cè)定提供了一種快速、靈敏、準(zhǔn)確的分析方法。
[Abstract]:The seaweed contains unsaturated fatty acids such as DHAA EPA, which is essential to our human body, which has nutritional value and medical value. Rapid, sensitive and accurate method for the determination of fatty acids in seaweed. It is of great significance to study the relationship between fatty acid and algal bioactivity. This paper aims to select the best derivatization reagent by comparing different derivatization reagents and fatty acid derivatization reactions. The structure of fatty acids was modified to improve the response signal of mass spectrometry. A fast, sensitive and accurate derivatization high performance liquid chromatography-tandem mass spectrometry (HPLC-MS) method was established. It has been applied to the determination of fatty acids in seaweed. The main contents are as follows: in the first part, the extraction methods of total lipids in seaweed were established, such as solvent extraction, ultrasonic extraction, Soxhlet extraction, etc. The improved Folch method was used to extract total lipids from seaweed powder, and the modified Folch method was used to extract total lipids from seaweed. The single factor experiment was used to select the ratio of liquid to material, extraction power, extraction temperature and extraction time. The optimum conditions were obtained as follows: the extraction solvent was methane-dichloromethane, the extraction time was 90 min, and the optimum temperature was 50 鈩，

本文編號(hào)：1690588