Medium design from corncob hydrolyzate for pigment production by Talaromyces atroroseus GH2: Kinetics modeling and pigments characterization


Lourdes Morales-Oyervides1,2, Juan Pablo Ruiz-Sánchez2, Jorge C. Oliveira1, Maria J. Sousa-Gallagher1, Thelma K. Morales-Martínez3, Ambrogina Albergamo4, Andrea Salvo5, Daniele Giuffrida4, Laurent Dufossé6, Julio Montañez2,*

1 School of Engineering, University College Cork, Cork, Ireland
2 Department of Chemical Engineering, Autonomous University of Coahuila. Saltillo, Coahuila, Mexico
3 Biotechnology Department, Autonomous University of Coahuila. Saltillo, Coahuila, Mexico
4 Dipartimento di Scienze Biomediche, Odontoiatriche e delle Immagini Morfologiche e Funzionali, University of Messina, Messina, Italy
5 Dipartimento di Chimica e Tecnologie del Farmaco, Facoltà di Farmacia e Medicina, Sapienza Università di Roma, Roma, Italy
6 Chimie et Biotechnologie des Produits Naturels & ESIROI Agroalimentaire, Université de la Réunion, Ile de la Réunion, France


The genus Talaromyces has gained attention due to its ability to produce pigments with potential industrial
applications in different areas. Prosperous application of fungal pigments has challenges to overcome, like developing a cost-effective bioprocess. Using agroindustrial wastes could provide inexpensive substrates and it contributes to maximize sustainability. Therefore, this study evaluated the feasibility of using corncob as a lowcost substrate for pigment production by Talaromyces atroroseus GH2. An acid hydrolysis treatment was used to release sugars from corncob. Corncob liquors with enough xylose concentration (> 20 g/L) were investigated as fermentation media with and without the addition of nutrients. Process kinetic modeling was applied and pigments produced in corncob and control media were characterized. The diluted hydrolyzate without nutrient supplementation showed a pigment production (16.17±0.37 OD500nm) comparable to the control medium (17.26±0.41 OD500nm). Talaromyces atroroseus GH2 was able to co-utilize xylose and glucose in the corncobbased medium. However, growth kinetics patterns differed in both media. In the hydrolyzate medium, biomass growth presented an extended lag phase, which requires reduction for future process optimization. Finally, characterized pigments differed among evaluated media, but the pigments produced by Talaromyces atroroseus GH2 were mostly Monascus’ pigments homologous like monascorubrin and rubropunctamine. Talaromyces atroroseus GH2 ability to produce pigments using corncob hydrolyzate makes it a pigment-producing strain for an economically competitive large fermentation scale.