脂肪酸的提取

1、精選文檔提取方法主要有BlighDyer法及Folch法。前者適用于大量脂類的提取，提取率在95甚至更高；后者適用于少量組織內脂的提取，提取率在9599。我們在試驗中常用Folch法。稱取1 g待測樣品，加入10 ml甲醇，加少量酸洗砂研磨，勻漿1 min，然后加入20 ml氯仿，連續(xù)勻漿2 min，過濾，濾渣中加入氯仿一甲醇混合液(2：1 VV)30 ml并研磨，過濾。先用20 ml氯仿及10 ml甲醇洗滌濾渣，合并濾液，然后加入全部濾液體積14的水，振蕩，靜置分層，將上層及界面處固體物吸除去，然后加入甲醇一水混合物(1：1)，體積為下層體積的14，振蕩，靜置分層，吸掉上層液體及界面物，重復

2、洗滌兩次。然后將有機相減壓蒸干，配制成氯仿溶液，一20下保存。留意：在分析植物組織中的脂質時，需要用加熱法使植物中的脂酶失活。1皂化、酯化 取約4 mg的總脂按CarreauDubacq法，加入約1 ml 15的NaOHMeOH(或1NaMeOH)溶液，在55。C水浴中加熱30 min，然后加入15 ml HClMeOH，水浴加熱30 min，加05 ml左右的蒸餾水，然后用4 mlEg烷萃取，吸取正己烷層，重復兩次。然后將萃取液減壓蒸干，加入03 ml氯仿。Modified Folch procedureHomogenised tissue (10 g) was progressively

3、added tosmall amounts of a chloroform/methanol 2:1 (v/v) mixture(up to 200 ml), with vigorous shaking, and then theextraction was carried on for a further 2h, using anelectromagnetic stirrer. The mixture was filtered and thefilter was re-washed with fresh solvent and pressed.Fifty millilitres of 0.8

4、8% potassium chloride were addedand the mixture was shaken. The aqueous layer (upper)was removed by aspiration and the washing procedurewas repeated. The extract was then dried by addinganhydrous sodium sulphate, which was filtered again,before the solvent was removed using a rotary evaporator.The e

5、xtract was then placed in a desiccatorovernight and weighedExtraction by acid hydrolysisHomogenised tissue (10 g) was progressively added tosmall amounts of a chloroform/methanol 2:1 (v/v) mixture(up to 200 ml), with vigorous shaking, and then theextraction was carried on for a further 2h, using ane

6、lectromagnetic stirrer. The mixture was filtered and thefilter was re-washed with fresh solvent and pressed.Fifty millilitres of 0.88% potassium chloride were addedand the mixture was shaken. The aqueous layer (upper)was removed by aspiration and the washing procedurewas repeated. The extract was then dried by addinganhydrous sodium sulphate, which was filtered again,before the solvent was removed using a