酵母β-葡聚糖制备工艺与过程分析

Preparation of β-glucan from Saccharomyces cerevisisae and the process analysis

酵母β-葡聚糖因具有抗肿瘤、增强免疫、抗氧化等多种生物活性而备受关注,但其制备方法多为酸碱法,不仅破坏了多糖的天然结构,且造成严重的环境污染。通过诱导自溶、高压微射流均质、复合酶解等技术确定了酵母β-葡聚糖制备的新工艺,即诱导自溶后高压微射流1处理条件为:压力210MPa、质量浓度湿重20%、循环3次;复合酶解参数为:酶添加量1.0%、温度55℃、pH7.0、酶解50min、料液比湿重1:4;复合酶解后高压微射流2作用参数为:压力210MPa、循环3次。上述条件下制备的酵母β-葡聚糖纯度为(81.07±0.82)%,产率为14.73%,该方法具有工艺简单易行、作用条件温和、清洁环保等优点,是一种产业化可行的制备方法。制备过程HPM1、复合酶解与HPM2对产物总糖含量和β-葡聚糖纯度有极显著影响,总糖从70.17%增加到91.60%,β-葡聚糖纯度由48.85%增加到81.07%,总氮含量随各处理步骤而逐渐减少,由51.18%减少到3.26%。在制备过程中,酵母的椭圆形立体结构逐渐被破坏,最终β-葡聚糖呈粗糙的扁平状形态。

β-glucan from Saccharomyces cerevisiae had many bioactivities, such as antitumor, immune- enhancement, antioxidant and so on. Most of yeast β-glucan preparation methods need to use acid or alkaline treatment, which may not only break the natural structure of β-glucan but also pollute the environment. In order to develop a clean preparation method, we found out a method including induced autolysis, high pressure microfluidization （HPM） and compound enzymolysis technics to prepare β-glucan from Saccharomyces cerevisisae. The optimum process conditions of yeast β-glucan extraction were HPM1 （pressure 210 MPa, concentrate of 20% wet weight, pass 3 times）, compound enzymolysis （enzyme concentration 1.0%, temperature 55℃, pH7.0, time 50 min, ratio of wet weight material to liquid1：4）, HPM2 （pressure 210 MPa, pass 3 times）. The purity of final yeast β-glucan was （81.07＋0.82）% and obtained at a yield of 14.73%. The new method of preparation yeast β-glucan had many advantages, such as mild working conditions, environment friendly and realizing large-scale preparation. Among all the preparation process, HPM1, compound enzymolysis and HPM2 processes had significant effect on the total sugar content and purity of 15-glucan which the total sugar content increased from 70.17% to 91.60% and 48.85% to 81.07%, respectively. However, the total nitrogen content decreased from 51.18% to 3.26% during the preparation processes and the oval-shaped structure of yeast had been destroyed gradually and changed into unshaped tabular form.