微光波对水葫芦水解糖化的促进机理研究

利用色质联机和扫描电镜等微观分析手段,研究了微波时间、功率和光波组合等对水葫芦理化性质、还原糖产量和水解副产物的影响规律.水葫芦叶子经过蒸汽加热和NaOH预处理后,酶水解的还原糖产量仅为239 mg（每100 mg底物）；而联合了微光波预处理后,可提高到311 mg（每100 mg底物）,使还原糖产量提高了301%.在微波和光波组合比例为30∶70（总功率700 W）、加热时间1 min时,得到了554%的理论最大还原糖产量.当微波功率过高或时间过长时,在预处理阶段由半纤维素水解生成的大量木糖进一步分解,导致乙酸、丁酮和糠醛等有害小分子副产物增加,对后期酶水解糖化和发酵产酒精造成不利影响.

Promotion mechanisms of microwave and lightwave pretreatments on enzymatic saccharification of water hyacinth

The gas chromatography-mass spectrometry (GC-MS) and scanning electron microscope (SEM) were used to study the effects of microwave time, power and combination with lightwave on the hyacinth (eichhornia crassipes) physicochemical properties, reducing sugar yields and hydrolysis byproducts. The reducing sugar yield of only 239 mg/100 mg hyacinth leave in the enzymatic hydrolysis was obtained when it was pretreated with the steam explosion and NaOH solution. The reducing sugar yield was increased by 301% to 311 mg/100 mg hyacinth leave when the microwave and lightwave pretreatments were additionally employed. The 554% of potential maximum sugars was released when the hyacinth leave was pretreated with the power ratio of microwave to lingtwave at 30∶70 (total power is 700 W) for 1 min. When the microwave power was higher and time was longer, more hydrolysis byproducts such as acetic acid, butanone and furfural were produced due to the further decomposition of the xylose derived from the hemicellulose hydrolysis, which was harmful to the following enzymatic saccharification and fermentative ethanol fuel．