Scale‐up and economic analysis of the production of ligninolytic enzymes from a side‐stream of the organosolv process

Abstract

BACKGROUND Organosolv pretreatment produces a hemicellulose‐rich stream with limited applications due to its toxicity. In this study, beech wood organosolv liquor was valorized through the production of ligninolytic enzymes, the extraction of ganoderic acid and the detoxification of this process stream. RESULTS Laccase and manganese peroxidase (MnP) were produced in 30 L bioreactors by the white‐rot fungi Ganoderma lucidum and Irpex lacteus, respectively, using the hemicellulose‐rich liquor as carbon source. Both fungi caused a significant reduction in the hemicellulose stream toxicity (between 6.1 and 8.3 times lower). The extraction of ganoderic acid (24.3 mg g−1 of G. lucidum biomass) as a fungal metabolite with high pharmacological activity greatly increased the profitability of the process. Finally, the economic viability of the proposed valorization strategy was analyzed on the basis of the operational costs estimated for the process scale‐up. The specific costs of MnP and laccase production were €2.27 kU−1and €1.08 kU−1, respectively, which are 1109 and 78 times lower than the average price of commercially available enzymes. CONCLUSION It was found that the integration of the proposed valorization strategy into an organosolv‐based biorefinery would help to increase the economic feasibility of this pretreatment technology. © 2018 Society of Chemical Industry

Bundling the removal of emerging contaminants with the production of ligninolytic enzymes from residual streams

“…As can be seen in Fig. 2 , the use of peptone stimulated enzyme production (Lú-Chau et al 2018 ; Pinheiro et al 2020 ).…”

“…4 , before the onset of enzyme production, the pH value decreased to around 4.4 and after the peak of MnP production, the pH increased again. On the other hand, the redox potential underwent an increase as more enzyme was produced, reaching its maximum value (500 mV) in parallel to the peak of enzyme production (Lú-Chau et al 2018 ). Another remarkable fact is that enzyme production started once the glucose concentration was below 0.8 g/L, similar to the trend observed in Erlenmeyer flask experiments.…”

“…Fermentations were carried out in triplicate with an initial pH of 4.5. The initial pH was selected based on previous works with WRF (Mäkelä et al 2013 ; Lú-Chau et al 2018 ) and aiming to promote the activity and stability of MnP (Qin et al 2014 ). The sampling strategy considered the periodic withdrawal of 3 mL of culture medium under sterile conditions, which were centrifuged for 10 min at 10,000 revolution per minute (rpm) to remove fungal biomass.…”

Laccases in food processing: Current status, bottlenecks and perspectives

“…They found that in solid state cultivation under optimized conditions, it was possible to produce laccase at laboratory scale, with a final price of 0.04 cent € per unit. More recently, laccase from the white-rot fungus Ganoderma lucidum was produced in 30 L bioreactors using the hemicellulose-rich liquor as carbon source (Lú-Chau et al, 2018). Economic analysis of the latter process resulted in a € 1.08 kU − 1 (0.01 cent € per unit).…”

Applications of Microbial Laccases: Patent Review of the Past Decade (2009–2019)

“…Most recently, the same strategy was adopted by [50] for the production of laccase from Ganoderma lucidum in 30 L bioreactors. The authors used the hemicellulose-rich, beechwood organosolv pretreatment stream as a growth medium for the cultivation and obtained up to 596 U L −1 of laccase activity.…”