The present study was aimed to evaluate the ability of Meyerozyma guilliermondii P14 to produce bioethanol from pretreated biomass of giant reed (Arundo donax). The wild yeast was isolated from its natural habitat and identified by phylogenetic analysis. Arundo donax biomass was sequentially pretreated by acid and alkali treatments to break the recalcitrant structure. The pretreated biomass was analysed by FTIR spectroscopy and scanning electron microscopy to observe the structural changes in the biomass. Pretreated biomass was then enzymatically saccharified, and the resultant broth was used to produce ethanol by M. guilliermondii P14. The fermentation parameters such as pH, temperature, composition of media, and agitation rate were optimized prior to saccharified broth-based fermentations. The results of this study revealed that the dual pretreatment of biomass could make 90.56% cellulose accessible for enzymatic attack. Subsequently, saccharification of pretreated biomass with two enzyme variants resulted in conversion efficiency of 85–87%. Fermentation of saccharified broth resulted in 32.89 g/L final ethanol concentration at 72 h. This has corresponded to 0.48 g/g of ethanol yield and 0.456 g/L/h volumetric productivity. M. guilliermondii is known to utilize both pentose and hexose sugars unlike Saccharomyces cerevisiae which makes it a major player in cellulosic ethanol production. This study provides a significant evidence to the information pool of second-generation bioethanol production from unconventional glucose fermenting yeasts.

本研究旨在评估Meyerozyma guilliermondii P14 从预处理过的大芦苇 ( Arundo donax ) 生物质生产生物乙醇的能力。野生酵母是从其自然栖息地中分离出来的，并通过系统发育分析进行鉴定。Arundo donax生物质通过酸和碱处理顺序预处理以打破顽固结构。通过FTIR光谱和扫描电子显微镜分析预处理的生物质以观察生物质的结构变化。然后对预处理的生物质进行酶促糖化，所得肉汤用于由M. guilliermondii生产乙醇P14。在糖化肉汤发酵之前优化发酵参数，例如 pH、温度、培养基组成和搅拌速率。这项研究的结果表明，生物质的双重预处理可以使 90.56% 的纤维素可用于酶促攻击。随后，用两种酶变体对预处理的生物质进行糖化，转化效率为 85-87%。糖化肉汤的发酵在 72 小时产生 32.89 g/L 的最终乙醇浓度。这对应于 0.48 g/g 的乙醇产率和 0.456 g/L/h 的体积生产率。M. guilliermondii与Saccharomyces cerevisiae不同，已知利用戊糖和己糖这使其成为纤维素乙醇生产的主要参与者。该研究为非常规葡萄糖发酵酵母生产第二代生物乙醇的信息库提供了重要证据。