A total 42.68 g/L monosaccharide with 0.10 g/L HMF was obtained from 10% (w/v) Kappaphycus alvarezii with thermal acid hydrolysis using 350 mM HNO₃ at 121 °C for 60 min and enzymatic saccharification with a 1:1 mixture of Viscozyme L and Celluclast 1.5 L for 72 h. To enhance the galactose utilization rate, fermentation was performed with overexpression of GAL1 (galactokinase), GAL7 (galactose-1-phosphate uridyltransferase), GAL10 (UDP-glucose-4-epimerase), and PGM2 (phosphoglucomutase 2) in Saccharomyces cerevisiae CEN.PK2 using CCW12 as a strong promoter. Among the strains, the overexpression of PGM2 showed twofold high galactose utilization rate (UR_gal) and produced ethanol 1.4-fold more than that of the control. Transcriptional analysis revealed the increase of PGM2 transcription level leading to enhance glucose-6-phosphate and fructose-6-phosphate and plays a key role in ensuring a higher glycolytic flux in the PGM2 strain. This finding shows particular importance in biofuel production from seaweed because galactose is one of the major monosaccharides in seaweeds such as K. alvarezii.

使用350 mM HNO ₃在121°C下进行60分钟的热酸水解并用1：1混合物进行酶促糖化反应，从10％（w / v）的Kappaphycus alvarezii中获得总含量为42.68 g / L单糖和0.10 g / L HMF。粘稠酶L和Celluclast 1.5 L混合72小时。为了提高半乳糖利用率，在酿酒酵母CEN中过表达GAL1（半乳糖激酶），GAL7（半乳糖-1-磷酸尿嘧啶转移酶），GAL10（UDP-葡萄糖-4-表观磷酸酶）和PGM2（磷酸葡萄糖变位酶2）进行发酵。 PK2使用CCW12作为强启动子。在菌株中，PGM2的过表达显示出两倍高的半乳糖利用率（UR _gal），产生的乙醇比对照高1.4倍。转录分析显示，PGM2转录水平的提高导致6磷酸葡萄糖和6磷酸果糖的增强，并且在确保PGM2菌株中较高的糖酵解通量中起关键作用。这一发现表明从海藻生产生物燃料特别重要，因为半乳糖是海藻（如K）中主要的单糖之一。阿尔瓦雷斯（Alvarezii）。