Jiménez-Nava Raziel Arturo, Chávez-Camarillo Griselda Ma, Cristiani-Urbina Eliseo
Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Unidad Profesional Adolfo López Mateos, Avenida Wilfrido Massieu s/n, Mexico City 07738, Mexico.
Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Colonia Santo Tomás, Prolongación de Carpio y Plan de Ayala s/n, Mexico City 11340, Mexico.
Microorganisms. 2025 Apr 3;13(4):817. doi: 10.3390/microorganisms13040817.
Riboflavin is biosynthesized and excreted extracellularly by the novel yeast . The steady-state kinetics of cell growth, substrate consumption, and riboflavin production by were studied in a chemostat continuous culture at different dilution rates. The unstructured Monod and Luedeking-Piret models were used to describe cell growth, substrate consumption, and riboflavin production, and crucial kinetic parameters were estimated. The experimental data fitted the proposed models well. The maximum specific growth rate, substrate affinity constant, maintenance energy coefficient, and maximum biomass yield values were 0.1378 h, 0.4166 g of glucose L, 0.1047 g of glucose g of biomass h, and 0.172 g of biomass g of glucose, respectively. The maximum yield from glucose and volumetric and specific productivities of riboflavin were 0.7487 mg of riboflavin g of glucose, 0.5593 mg of riboflavin L h, and 0.6547 mg of riboflavin g of biomass h, respectively. The estimated growth-associated riboflavin production constant (4.88 mg of riboflavin g of biomass) was much higher than the non-growth-associated riboflavin production constant (0.0022 mg of riboflavin g of biomass h), indicating that riboflavin production by is a predominantly growth-associated process. The chemostat continuous culture offers a promising strategy for efficiently and sustainably producing riboflavin using .
核黄素由这种新型酵母在细胞外进行生物合成和分泌。在恒化器连续培养中，研究了不同稀释率下该酵母的细胞生长、底物消耗和核黄素生产的稳态动力学。采用非结构的莫诺德模型和吕德金-皮雷特模型来描述细胞生长、底物消耗和核黄素生产，并估算了关键动力学参数。实验数据与所提出的模型拟合良好。最大比生长速率、底物亲和常数、维持能量系数和最大生物量得率值分别为0.1378 h⁻¹、0.4166 g葡萄糖/L、0.1047 g葡萄糖/（g生物量·h）和0.172 g生物量/g葡萄糖。葡萄糖的最大得率以及核黄素的体积产率和比产率分别为0.7487 mg核黄素/g葡萄糖、0.5593 mg核黄素/（L·h）和0.6547 mg核黄素/（g生物量·h）。估算的与生长相关的核黄素生产常数（4.88 mg核黄素/g生物量）远高于与非生长相关的核黄素生产常数（0.0022 mg核黄素/（g生物量·h）），这表明该酵母生产核黄素主要是一个与生长相关的过程。恒化器连续培养为利用该酵母高效、可持续地生产核黄素提供了一种有前景的策略。
