Sawhney Diksha, Vaid Surbhi, Bangotra Ridhika, Sharma Surbhi, Dutt Harish Chander, Kapoor Nisha, Mahajan Ritu, Bajaj Bijender Kumar
School of Biotechnology, University of Jammu, Jammu 180006, India.
Department of Botany, University of Jammu, Jammu 180006, India.
Bioresour Technol. 2023 May;375:128791. doi: 10.1016/j.biortech.2023.128791. Epub 2023 Mar 5.
Current study is the first report of the combined application of chemical (deep eutectic solvent), physical (microwave irradiation) and biological (laccase) pretreatment strategies for enhancing the enzymatic digestibility of rice straw biomass. Pretreated rice straw biomass was saccharified by cellulase/xylanase from Aspergillus japonicus DSB2 to get a sugar yield of 252.36 mg/g biomass. Design of Experiment based optimization of pretreatment and saccharification variables increased the total sugar yield by 1.67 times (421.5 mg/g biomass, saccharification efficiency 72.6%). Sugary hydrolysate was ethanol-fermented by Saccharomyces cerevisiae and Pichia stipitis to achieve an ethanol yield of 214 mg/g biomass (bioconversion efficiency 72.5%). Structural/chemical aberrations induced in the biomass due to pretreatment were elucidated by X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and H nuclear magnetic resonance techniques to unravel the pretreatment mechanisms. Combined application of various physico-chemical/biological pretreatment may be a promising approach for proficient bioconversion of rice straw biomass.
当前的研究首次报道了化学（深共熔溶剂）、物理（微波辐射）和生物（漆酶）预处理策略联合应用以提高稻草生物质酶解消化率的情况。预处理后的稻草生物质用来自日本曲霉DSB2的纤维素酶/木聚糖酶进行糖化，得到的糖产量为252.36毫克/克生物质。基于实验设计对预处理和糖化变量进行优化后，总糖产量提高了1.67倍（421.5毫克/克生物质，糖化效率72.6%）。含糖水解产物由酿酒酵母和树干毕赤酵母进行乙醇发酵，乙醇产量达到214毫克/克生物质（生物转化效率72.5%）。通过X射线衍射、扫描电子显微镜、傅里叶变换红外光谱和氢核磁共振技术阐明了预处理导致生物质结构/化学变化，以揭示预处理机制。各种物理化学/生物预处理的联合应用可能是稻草生物质高效生物转化的一种有前景的方法。
