壳聚糖对脂肪的吸附特性

Fat-Binding Characteristics of Chitosan

以花生油为吸附对象,在模拟人体消化液中做体外实验,通过改变介质的条件,测定壳聚糖(CS)对脂肪的吸附量(FBC),研究壳聚糖在体外对脂肪的吸附能力,考察其脂肪吸附特性,分析壳聚糖的FBC与其分子构象形态之间的关系。结果表明:在pH2～3介质中壳聚糖的脂肪吸附量是其在pH6.4～7.2介质中的3倍左右;当壳聚糖在pH2盐酸生理盐水溶液中的质量浓度为0.010～0.0067g/mL时,壳聚糖对脂肪的吸附量较大;中等相对分子质量的壳聚糖(4.0×105)对脂肪的吸附量较大;当脂肪与壳聚糖的质量比为30:1时,壳聚糖对脂肪的吸附量最大。吸附量取决于壳聚糖大分子链在不同的环境介质下存在的构象形态对脂肪所产生的主导绑定作用。吸附时间达到2h后,吸附量的增加趋于平缓。

in vitro binding studies of peanut oil to chitosan（CS） were carried out in stimulated digestive juice.Fat-binding characteristics of chitosan were investigated by measuring its fat-binding capacity（FBC） under various conditions.Meanwhile,the relationship of FBC with molecular structure for chitosan was analyzed.Chitosan showed an approximately 3-fold increase in FBC at pH 2—3 compared with pH 6.4—7.2.A higher FBC level was found for chitosan at 0.010—0.0067 g/mL in normal saline solution adjusted to pH 2 with hydrochloric acid.Similarly,middle molecular weight chitosan had a higher FBC level.The maximum FBC level was attained for chitosan when mixed with peanut oil at a mass ratio of 1：30.The FBC level of chitosan was dependent on its chain conformation.During the binding process,the FBC level of chitosan increased in the first 2 h,and then reached a plateau.