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Despite decades of research and industrial applications of Trichoderma reesei, the development of industrially relevant strains for enzyme production including a low-cost and scalable bioprocess remains elusive. Herein, bioprocess optimization, pilot plant scale-up, techno-economic analysis and life-cycle assessment for enzyme production by an engineered T. reesei strain are reported. The developed bioprocess increased in ∼ 2-fold protein productivity (0.39 g.L -1 .h -1 ) and 1.6-fold FPase activity (196 FPU.L -1 .h -1 ), reducing the fermentation in 4 days. Cultivation in a 65-L pilot plant bioreactor resulted in 54 g.L -1 protein in 7 days, highlighting the robustness and scalability of this bioprocess. Techno-economic analysis indicates an enzyme cost of ∼ 3.2 USD.kg -1 , which is below to the target proposed (4.24 USD.kg -1 ) in the NREL/TP-5100-47764 report, while life-cycle assessment shows a carbon footprint reduction of approximately 50% compared to a typical commercial enzyme. This study provides the fundamental knowledge for the design of economically competitive Trichoderma technologies for industrial use., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The determination of optimum values of volumetric oxygen transfer coefficient (k L a) for Spathaspora passalidarum is an important aspect for the optimization of ethanol production from pentoses since oxygen plays a key role on yeast metabolism. By studying the fermentation of a xylose and glucose mixture, the highest ethanol volumetric productivity was achieved at a k L a of 45 h -1 (1.12 g ethanol L -1  h -1 ), reducing the fermentation time to half when compared to other oxygen-limiting conditions that were considered optimum for other native strains, besides increasing xylose consumption rates. The high cell density fermentation showed to be a good strategy to be applied in industrial processes with S. passalidarum, enabling the complete exhaustion of a high initial substrate concentration (90 g L -1 ) in less than 24 h, with a final ethanol titer of 28.61 (± 0.42) g L -1 . By performing a detailed investigation on oxidation-reduction potential (ORP), it was possible to conclude that the highest ethanol formation rates were registered at oxireduction potential values around - 100 mV, becoming an important parameter to be controlled when oxygen-limiting conditions are applied in industrial fermentations. The oxygen availability also affected the activity of enzyme XR and its preference for NADH or NADPH, directly affecting the activity of enzyme XDH and the redox imbalance on the xylose pathway. In addition, respirometric parameters were determined for the yeast S. passalidarum under an aerobic growth condition.

This study aimed to evaluate the effect of the level of crude glycerin (CG) on in vitro fermentation kinetics (0, 20, 40, 60, and 80 g/kg DM of sugar cane silage), on in vitro neutral detergent fiber (NDF) degradation (0, 30, 60, and 90 g/kg DM of sugar cane silage), and intake and digestibility of nutrients and nitrogen balance (0, 20, 55, 82, and 108 g/kg DM of sugar cane silage) in lambs. The in vitro trials were conducted in a completely randomized design with three repetitions. The in vivo trial was conducted in a Latin square design with five repetitions (5 × 5). For variables in which the F test was considered significant, the statistical interpretation of the effect of CG substitution levels was carried out through regression analyses. Kinetic parameters were not affected by CG inclusion. On in vitro NDF degradation, a significant effect of CG levels was observed on the potentially degradable fraction of NDF, the insoluble potentially degradable fraction of NDF, and the undegradable NDF fraction. The intake and digestibility of nutrients and nitrogen balance were not affected by CG inclusion. The CG levels change in vitro NDF degradability parameters; however, there were no changes in animal intake, digestibility, and nitrogen balance with the inclusion levels used.

The objective of this study was to evaluate intake and apparent digestibility of agro-industrial by-product of peach palm in diets for lambs. Twenty castrated, crossbred Santa Ines lambs, with average age of 150 days and body weight of 22.4 ± 3.4 kg, were distributed in a completely randomized design with four experimental diets composed of the following: fresh by-product of peach palm enriched with urea + ammonia sulfate (FU); fresh peach palm by-product + concentrate (FP); silage of peach palm by-product + concentrate (SP); and silage of peach palm by-product enriched with 15% of cornmeal + concentrate (SPC). Intake was recorded daily, and the digestibility coefficients were estimated with the internal marker indigestible acid detergent fiber (iADF). Diet FU resulted in the lowest intake and digestibility of the nutrients evaluated. Animals receiving diet FP showed higher intakes of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), total digestible nutrients (TDN), and digestible energy (DE) in relation to animals fed diets SP and SPC. Diets SP and SPC showed higher coefficients of digestibility of DM, OM, CP, and NDF than diet FP. Diet SP reduced the intakes of DM, OM, ether extract (EE), non-fibrous carbohydrate (NFC), TDN, and DE and the digestibility coefficients of DM, OM, and NFC as compared with diet SPC. Feedlot lambs fed a diet with fresh peach palm by-product + concentrate (diet FP) have higher nutrient intake.