Lee Dahye, Semidey Fransheska, Xu Luping, Oh Eun Joong
Department of Food Science, Purdue University, West Lafayette, IN 47907, USA.
Whistler Center for Carbohydrate Research, Purdue University, West Lafayette, IN 47907, USA.
J Microbiol. 2025 Jul;63(7):e2503001. doi: 10.71150/jm.2503001. Epub 2025 Jul 31.
Pectin-rich biomass, derived from fruit and citrus processing waste, presents a promising yet underutilized resource for sustainable biofuel and biochemical production. Its low lignin content and high concentrations of fermentable sugars, including D-galacturonic acid, L-arabinose, and D-xylose, make it an attractive feedstock. Unlike lignocellulosic biomass, pectin-rich hydrolysates require milder pretreatment, improving sugar recovery efficiency. However, industrial strains such as Saccharomyces cerevisiae exhibit strong glucose preference, limiting the efficient co-fermentation of mixed sugars. While prior reviews have broadly addressed lignocellulosic biomass utilization, this mini-review uniquely centers on the specific metabolic challenges and opportunities associated with pectin-rich feedstocks. In addition to incorporating established strategies for the co-utilization of cellobiose and xylose, we highlight recent advances that allow S. cerevisiae to metabolize carbon sources specifically from pectin-rich biomass, such as L-arabinose and D-galacturonic acid-monomers not prevalent in traditional lignocellulosic biomass. By integrating discussions on sugar transport engineering, redox balancing, and pathway optimization, this review offers a comprehensive framework to overcome glucose repression and support efficient co-fermentation of carbon sources from conventional and pectin-rich biomass. Drawing on these advances, we outline practical strategies to enhance fermentation performance and expand the valorization of food processing residues in biomanufacturing.
源自水果和柑橘加工废料的富含果胶的生物质，是可持续生物燃料和生化产品生产中一种前景广阔但未得到充分利用的资源。其低木质素含量以及高浓度的可发酵糖，包括D-半乳糖醛酸、L-阿拉伯糖和D-木糖，使其成为一种有吸引力的原料。与木质纤维素生物质不同，富含果胶的水解产物需要更温和的预处理，从而提高糖的回收效率。然而，像酿酒酵母这样的工业菌株表现出对葡萄糖的强烈偏好，限制了混合糖的高效共发酵。虽然先前的综述广泛探讨了木质纤维素生物质的利用，但本小型综述独特地聚焦于与富含果胶的原料相关的特定代谢挑战和机遇。除了纳入已有的纤维二糖和木糖共利用策略外，我们还强调了最近的进展，这些进展使酿酒酵母能够代谢富含果胶的生物质中的特定碳源，例如L-阿拉伯糖和D-半乳糖醛酸单体，这些单体在传统木质纤维素生物质中并不常见。通过整合关于糖转运工程、氧化还原平衡和途径优化的讨论，本综述提供了一个全面的框架，以克服葡萄糖抑制并支持传统生物质和富含果胶的生物质中碳源的高效共发酵。基于这些进展，我们概述了提高发酵性能和扩大生物制造中食品加工残渣价值化的实用策略。
