Lignocellulosic materials valorization in second generation biorefineries: an opportunity to produce fungal biopigments.

Second generation biorefineries play an important role in the production of renewable energy and fuels, utilizing forest and agro-industrial residues and by-products as raw materials. The integration of novel bioproducts, such as: xylitol, ß-carotene, xylooligosaccharides, and biopigments into the biorefinery's portfolio can offer economic benefits in the valorization of lignocellulosic materials, particularly cellulosic and hemicellulosic fractions. Fungal biopigments, known for their additional antioxidant and antimicrobial properties, are appealing to consumers and can have applications in various industrial sectors, including food and pharmaceuticals. The use of lignocellulosic materials as carbon and nutrient sources for the growth medium helps to reduce production costs, increasing the competitiveness of fungal biopigments in the market. In addition, the implementation of biopigment production in biorefineries allows the utilization of underutilized fractions, such as hemicellulose, for value-added bioproducts. This study deals with the potential of fungal biopigments production in second generation biorefineries in order to diversify the produced biomolecules together with energy generation. A comprehensive and critical review of the recent literature on this topic has been conducted, covering the major possible raw materials, general aspects of second generation biorefineries, the fungal biopigments and their potential for incorporation into biorefineries.

Using low-shear aerated and agitated bioreactor for producing two specific laccases by trametes versicolor cultures induced by 2,5-xylidine: Process development and economic analysis.

Laccase isoforms from basidiomycetes exhibit a superior redox potential compared to commercially available laccases obtained from ascomycete fungi, rendering them more reactive toward mono-substituted phenols and polyphenolic compounds. However, basidiomycetes present limitations for large-scale culture in liquid media, restraining the current availability of laccases from this fungal class. To advance laccase production from basidiomycetes, a newly designed 14-L low-shear aerated and agitated bioreactor provided enzyme titers up to 23.5 IU/mL from Trametes versicolor cultures. Produced enzymes underwent ultrafiltration and LC/MS-MS characterization, revealing the predominant production of only two out of the ten laccases predicted in the T. versicolor genome. Process simulation and economic analysis using SuperPro designer® suggested that T. versicolor laccase could be produced at US$ 3.60/kIU in a 200-L/batch enterprise with attractive economic parameters and a payback period of 1.7 years. The study indicates that new bioreactors with plain design help to produce low-cost enzymes from basidiomycetes.