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Fungal lipolytic enzymes play crucial roles in various lipid bio-industry processes. Here, we elucidated the biochemical and structural characteristics of an unexplored fungal lipolytic enzyme (TaLip) from Thermoascus aurantiacus var. levisporus, a strain renowned for its significant industrial relevance in carbohydrate-active enzyme production. TaLip belongs to a poorly understood phylogenetic branch within the class 3 lipase family and prefers to hydrolyze mainly short-chain esters. Nonetheless, it also displays activity against natural long-chain triacylglycerols. Furthermore, our analyses revealed that the surfactant sodium dodecyl sulfate (SDS) enhances the hydrolytic activity of TaLip on pNP butyrate by up to 5.0-fold. Biophysical studies suggest that interactions with SDS may prevent TaLip aggregation, thereby preserving the integrity and stability of its monomeric form and improving its performance. These findings highlight the resilience of TaLip as a lipolytic enzyme capable of functioning in tandem with surfactants, offering an intriguing enzymatic model for further exploration of surfactant tolerance and activation in biotechnological applications., 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 © 2024 Elsevier Inc. All rights reserved.)

The enzymatic decarboxylation of fatty acids (FAs) represents an advance toward the development of biological routes to produce drop-in hydrocarbons. The current mechanism for the P450-catalyzed decarboxylation has been largely established from the bacterial cytochrome P450 OleT JE . Herein, we describe OleTP RN , a poly-unsaturated alkene-producing decarboxylase that outrivals the functional properties of the model enzyme and exploits a distinct molecular mechanism for substrate binding and chemoselectivity. In addition to the high conversion rates into alkenes from a broad range of saturated FAs without dependence on high salt concentrations, OleTP RN can also efficiently produce alkenes from unsaturated (oleic and linoleic) acids, the most abundant FAs found in nature. OleTP RN performs carbon-carbon cleavage by a catalytic itinerary that involves hydrogen-atom transfer by the heme-ferryl intermediate Compound I and features a hydrophobic cradle at the distal region of the substrate-binding pocket, not found in OleT JE , which is proposed to play a role in the productive binding of long-chain FAs and favors the rapid release of products from the metabolism of short-chain FAs. Moreover, it is shown that the dimeric configuration of OleTP RN is involved in the stabilization of the A-A' helical motif, a second-coordination sphere of the substrate, which contributes to the proper accommodation of the aliphatic tail in the distal and medial active-site pocket. These findings provide an alternative molecular mechanism for alkene production by P450 peroxygenases, creating new opportunities for biological production of renewable hydrocarbons.

Microbial resistance to drugs is a public health problem; therefore, there is a search for alternatives to replace conventional products with natural agents. One of the potential antimicrobial agents is wood vinegar derived from the carbonization of lignocellulosic raw materials. The objectives of the present work were to evaluate the antibacterial and antifungal action of two kinds of wood vinegar (WV), one of Eucalyptus urograndis wood and another of Bambusa vulgaris biomass, and determine their chemical profile. The antimicrobial effect was assessed against Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enteritidis, Escherichia coli, Streptococcus agalactiae, and Candida albicans. The minimum inhibitory concentration and the minimum bactericidal and fungicidal concentrations were determined. Micrographs of the microorganisms before and after exposure to both kinds of wood vinegar were obtained by scanning electron microscopy. The chemical profile of the eucalyptus and bamboo vinegar was carried out by gas chromatography and mass spectrometry (GC/MS). Both types of WV presented significant antimicrobial activity, with the bamboo one having a higher efficiency. Both studied pyroligneous extracts seem promising for developing natural antimicrobials due to their efficiency against pathogens. GC/MS analyses demonstrated that the chemical profiles of both kinds of WV were similar but with some significant differences. The major component of the eucalyptus vinegar was furfural (17.2%), while the bamboo WV was phenol (15.3%). Several compounds in both WVs have proven antimicrobial activity, such as acetic acid, furfural, phenol, cresols, guaiacol, and xylenols. Together, they are the major in the chemical composition of the organic fraction of both WVs. Bamboo vinegar had a more expressive content of organic acids. Micrographs of microorganisms taken after exposure to both kinds of wood vinegar displayed several cell modifications. The potential of both types of wood vinegar as a basis for natural antimicrobial products seems feasible due to their proven effect on inhibiting the microorganisms' growth assessed in this experiment., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Reusing agro-industrial waste does not only help to mitigate environmental impact but also enables valorization through the development of new products. The aim is to enhance the physical and mechanical properties of particleboard panels produced with Eucalyptus wood and different proportions of waste products-coconut fiber (Cocos nucifera L.). Physical properties (density, water absorption, and thickness swelling) and mechanical properties (static bending and internal bond resistance) were assessed, and panels reinforced with coconut fiber showed the best qualities with higher density, greater dimensional stability, and less water absorption. Static bending resistance and internal bond resistance also increased significantly. This demonstrated the potential of achieving compatible characteristics for civil construction and furniture production through the inclusion of waste material. The impact of this research is obtained from the utilization of an important agro-industrial residue in the manufacture of permanent composites., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Isomerases are enzymes that induce physical changes in a molecule without affecting the original molecular formula. Among this class of enzymes, xylose isomerases (XIs) are the most studied to date, partly due to their extensive application in industrial processes to produce high-fructose corn sirups. In recent years, the need for sustainable initiatives has triggered efforts to improve the biobased economy through the use of renewable raw materials. In this context, D-xylose usage is crucial as it is the second-most abundant sugar in nature. The application of XIs in biotransforming xylose, enabling downstream metabolism in several microorganisms, is a smart strategy for ensuring a low-carbon footprint and producing several value-added biochemicals with broad industrial applications such as in the food, cosmetics, pharmaceutical, and polymer industries. Considering recent advancements that have expanded the range of applications of XIs, this review provides a comprehensive and concise overview of XIs, from their primary sources to the biochemical and structural features that influence their mechanisms of action. This comprehensive review may help address the challenges involved in XI applications in different industries and facilitate the exploitation of xylose bioprocesses.

This work presents an automatic slip control solution applied to a two-wheel-drive (2WD) electric tractor. Considering that the slip can be maintained within a specific range that depends on the type of soil, it is possible to increase the tractive efficiency of the electric vehicle (EV). The control system can be easily designed considering only the longitudinal dynamics of the tractor while using simple proportional-integral (PI) controllers to drive the inverters associated with the rear wheels. The introduced solution is tested on an experimental electric tractor prototype traveling on firm soil considering case studies in which the slip control is enabled and disabled. The acquired results demonstrate that the slip control allows for obtaining a more stable performance and reduced energy consumption.

Understanding the aspects that contribute to improving proteins' biochemical properties is of high relevance for protein engineering. Properties such as the catalytic rate, thermal stability, and thermal resistance are crucial for applying enzymes in the industry. Different interactions can influence those biochemical properties of an enzyme. Among them, the surface charge-charge interactions have been a target of particular attention. In this study, we employ the Tanford-Kirkwood solvent accessibility model using the Monte Carlo algorithm (TKSA-MC) to predict possible interactions that could improve stability and catalytic rate of a WT xylanase (XynA WT ) and its M6 xylanase (XynA M6 ) mutant. The modeling prediction indicates that mutating from a lysine in position 99 to a glutamic acid (K99E) favors the native state stabilization in both xylanases. Our lab results showed that mutated xylanases had their thermotolerance and catalytic rate increased, which conferred higher processivity of delignified sugarcane bagasse. The TKSA-MC approach employed here is presented as an efficient computational-based design strategy that can be applied to improve the thermal resistance of enzymes with industrial and biotechnological applications., (Copyright © 2021 Biophysical Society. Published by Elsevier Inc. All rights reserved.)

Trichoderma genus fungi present great potential for the production of carbohydrate-active enzymes (CAZYmes), including glycoside hydrolase (GH) family members. From a renewability perspective, CAZYmes can be biotechnologically exploited to convert plant biomass into free sugars for the production of advanced biofuels and other high-value chemicals. GH54 is an attractive enzyme family for biotechnological applications because many GH54 enzymes are bifunctional. Thus, GH54 enzymes are interesting targets in the search for new enzymes for use in industrial processes such as plant biomass conversion. Herein, a novel metal-dependent GH54 arabinofuranosidase (ThABF) from the cellulolytic fungus Trichoderma harzianum was identified and biochemically characterized. Initial in silico searches were performed to identify the GH54 sequence. Next, the gene was cloned and heterologously overexpressed in Escherichia coli. The recombinant protein was purified, and the enzyme's biochemical and biophysical properties were assessed. GH54 members show wide functional diversity and specifically remove plant cell substitutions including arabinose and galactose in the presence of a metallic cofactor. Plant cell wall substitution has a major impact on lignocellulosic substrate conversion into high-value chemicals. These results expand the known functional diversity of the GH54 family, showing the potential of a novel arabinofuranosidase for plant biomass degradation.

Cold-adapted endo-β-1,4-glucanases hold great potential for industrial processes requiring high activity at mild temperatures such as in food processing and extraction of bioactive compounds from plants. Here, we identified and explored the specificity, mode of action, kinetic behavior, molecular structure and biotechnological application of a novel endo-β-1,4-glucanase (XacCel8) from the phytopathogen Xanthomonas citri subsp. citri. This enzyme belongs to an uncharacterized phylogenetic branch of the glycoside hydrolase family 8 (GH8) and specifically cleaves internal β-1,4-linkages of cellulose and mixed-linkage β-glucans releasing short cello-oligosaccharides ranging from cellobiose to cellohexaose. XacCel8 acts in near-neutral pHs and in a broad temperature range (10-50 °C), which are distinguishing features from conventional thermophilic β-1,4-glucanases. Interestingly, XacCel8 was greatly stimulated by cobalt ions, which conferred higher conformational stability and boosted the enzyme turnover number. The potential application of XacCel8 was demonstrated in the caffeine extraction from guarana seeds, which improved the yield by 2.5 g/kg compared to the traditional hydroethanolic method (HEM), indicating to be an effective additive in this industrial process. Therefore, XacCel8 is a metal-stimulated and cold-adapted endo-β-1,4-glucanase that could be applied in a diverse range of biotechnological processes under mild conditions such as caffeine extraction from guarana seeds., 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 © 2020 Elsevier B.V. All rights reserved.)

Aquaculture is an activity with economic and social importance since it generates food, employment, and income. However, like other human activities, it negatively impacts the environment, in this respect mainly due to the production of effluents rich in sedimentable solids, organic matter, phosphorus, and nitrogen. These last two are responsible for the eutrophication of water courses, causing changes in the aquatic biota. Hence, there is a need to adopt strategies to improve the efficiency of wastewater reuse. In this sense, the objective of this work was to evaluate the efficiency of using the floating aquatic macrophytes Eichhornia crassipes, Pistia stratiotes, and Salvinia molesta for the treatment of aquaculture effluents. The experiment was conducted in a completely randomized design, with seven treatments and three repetitions; the treatments were the following: T1, without plant, treated only with sedimentation; T2, Eichhornia crassipes; T3, Pistia stratiotes; T4, Salvinia molesta; T5, Eichhornia crassipes and Pistia stratiotes; T6, Eichhornia crassipes and Salvinia molesta; and T7, Pistia stratiotes and Salvinia molesta. The treatments were evaluated for a period of 168 h: the first collection of effluent allowed analysis of the raw effluent; the second occurred 24 h after the first collection and the others, on alternate days with 72, 120, and 168 h, totaling five collections in each experimental unit. The effluent used came from breeding tanks of Nile Tilapia (Oreochromis niloticus). The quality of the effluent was evaluated by the rate of removal of nutrients N-total, N-nitrite, N-nitrate, N-ammoniacal and Ptotal, temperature, pH, turbidity, dissolved oxygen, electrical conductivity, total alkalinity, BDO, and CDO. After the effluent was treated, the values of the parameters were compared with the maximum admissible values (MAVs), as specified by Brazil's National Environmental Council (CONAMA) in Resolutions 430/2011 and 357/2005. With the use of floating aquatic macrophytes, the concentrations of all evaluated limnology parameters improved significantly. There was also an improvement in the physical aspect of the effluent (transparency and turbidity). Thus, it can be concluded that the use of the macrophytes Eichhornia crassipes, Pistia stratiotes, and Salvinia molesta is effective in the treatment of effluents from fish farming.

Macaw palm is a highly oil-producing plant, which presents high contents of free fatty acids, being a promising feedstock for biofuel production. The current chemical routes are costly and complex, involving highly harsh industrial conditions. Enzymatic processing is a potential alternative; however, it is hampered by the scarce knowledge on biocatalysts adapted to this acidic feedstock. This work describes a novel lipase isolated from the thermophilic fungus Rasamsonia emersonii ( Re Lip), which tolerates extreme conditions such as the presence of methanol, high temperatures, and acidic medium. Among the tested feedstocks, the enzyme showed the highest preference for macaw palm oil, producing a hydrolyzate with a final free fatty acid content of 92%. Crystallographic studies revealed a closed conformation of the helical amphipathic lid that typically undergoes conformational changes in a mechanism of interfacial activation. Such conformation of the lid is stabilized by a salt bridge, not observed in other structurally characterized homologs, which is likely involved in the tolerance to organic solvents. Moreover, the lack of conservation of the aromatic cluster IxxWxxxxxF in the lid of Re Lip with the natural mutation of the phenylalanine by an alanine might be correlated with the preference of short acyl chains, although preserving catalytic activity on insoluble substrates. In addition, the presence of five acidic amino acids in the lid of Re Lip, a rare property reported in other lipases, may have contributed to its ability to tolerate and be effective in acidic environments. Therefore, our work describes a new fungal biocatalyst capable of efficiently hydrolyzing macaw oil, an attractive feedstock for the production of "drop-in" biofuels, with high desirable feature for industrial conditions such as thermal and methanol tolerance, and optimum acidic pH. Moreover, the crystallographic structure was elucidated, providing a structural basis for the enzyme substrate preference and tolerance to organic solvents., (Copyright © 2020 Rade, da Silva, Vieira, Milan, de Souza, de Melo, Klein, Bonomi, de Castro, Murakami and Zanphorlin.)

Background: Enzymatic isomerization is a promising strategy to solve the problem of xylose fermentation and, consequently, to leverage the production of advanced biofuels and biochemicals. In a previous work, our research group discovered a new strain of Streptomyces with great biotechnological potential due to its ability to produce a broad arsenal of enzymes related to lignocellulose degradation., Methods: We applied a multidisciplinary approach involving enzyme kinetics, biophysical methods, small angle X-ray scattering and X-ray crystallography to investigate two novel xylose isomerases, XylA1F1 and XylA2F1, from this strain., Results: We showed that while XylA1F1 prefers to act at lower temperatures and relatively lower pH, XylA2F1 is extremely stable at higher temperatures and presents a higher turnover number. Structural analysis revealed that XylA1F1 exhibits unique properties in the active site not observed in classical XylAs from classes I and II nor in its ortholog XylA2F1. It encompasses the natural substitutions, M86A and T93K, that create an extra room for substrate accommodation and narrow the active-site entrance, respectively. Such modifications may contribute to the functional differentiation of these enzymes., Conclusions: We have characterized two novel xylose isomerases that display distinct functional behavior and harbor unprecedented amino-acid substitutions in the catalytic interface., General Significance: Our findings contribute to a better understanding of the functional and structural aspects of xylose isomerases, which might be instrumental for the valorization of the hemicellulosic fraction of vegetal biomass., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Adhesive-free wood-plastic composite panels made with lignocellulosic wastes, and recycled plastics can be a sustainable option for generating useful "green" products. The present work assessed the physical-mechanical properties of adhesive-free panels produced with Qualea sp. sawdust and recycled polypropylene (PP). Discarded PP packaging was used. The packages were washed and ground with a laboratory knife mill until particle size of 10 to 14 mesh. Qualea sp. sawdust was sieved to select particle size of 14 to 30 mesh. Four experimental treatments were assessed by varying the percentages of PP and sawdust, as follows, 60 and 40%, 70 and 30%, 80 and 20%, and 90 and 10%, in an entirely randomized design with 3 panels per treatment, totaling 12 panels. The mats were hot-pressed at 180 °C during 20 min, the first 10 min under pressure of 1.0 MPa and the remaining 10 min at 42 MPa. Physical-mechanical properties of the panels were obtained as follows: density, moisture content, water absorption, thickness swelling, moduli of elasticity and rupture, and Rockwell hardness. In general, an increase of the percentage of PP provided higher dimensional stability to the panels, but there was no significant influence on mechanical strength.

L-asparaginase (L-asparagine amidohydrolase EC 3.5.1.1) is of great importance in pharmaceutical and food applications. This review aims to describe the production and use of fungal L-asparaginase focusing on its potential as an effective reducer of acrylamide in different food applications. Fungal asparaginases have been used as food additives and have gained importance due to some technical advantages, for example, fungi can grow using low-cost culture mediums, and the enzyme is extracellular, which facilitates purification steps. Research aimed at the discovery of new L-asparaginases, mainly those produced by fungi, have great potential to obtain cheaper enzymes with desirable properties for application in food aiming at the reduction of acrylamide., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The popularity of transglutaminase (TG) by the food industry and the variation in functionality of this enzyme from different origins, prompted us to isolate and evaluate a high-yielding TG strain. Through the statistical approaches, Plackett-Burman and response surface methodology, a low cost fermentation media was obtained to produce 6.074±0.019UmL -1 of TG from a novel source; Streptomyces sp. CBMAI 1617 (SB6). Its potential exploitation was compared to commonly used TG, from Streptomyces mobaraensis. Biochemical and FT-IR studies indicated differences between SB6 and commercial TG (Biobond™ TG-M). Additions of TG to wheat protein and flour based doughs revealed that the dough stretching depended on the wheat protein fraction, TG amount and its origin. A higher degree of cross-linking of glutenins and of inclusion of gliadin in the polymers was seen for SB6 as compared to commercial TG. Thus, our results support the potential of SB6 to tailor wheat protein properties within various food applications., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

An Aspergillus niger UFV-1 phytase was characterized and made available for industrial application. The enzyme was purified via ultrafiltration followed by acid precipitation, ion exchange and gel filtration chromatography. This protein exhibited a molecular mass of 161 kDa in gel filtration and 81 kDa in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), indicating that it may be a dimer. It presented an optimum temperature of 60 °C and optimum pH of 2.0. The K M for sodium phytate hydrolysis was 30.9 mM, while the k cat and k cat / K M were 1.46 ×10 (5) s (-1) and 4.7 × 10 (6) s (-1) .M (-1) , respectively. The purified phytase exhibited broad specificity on a range of phosphorylated compounds, presenting activity on sodium phytate, p-NPP, 2- naphthylphosphate, 1- naphthylphosphate, ATP, phenyl-phosphate, glucose-6-phosphate, calcium phytate and other substrates. Enzymatic activity was slightly inhibited by Mg (2+) , Cd (2+) , K (+) and Ca (2+) , and it was drastically inhibited by F (-) . The enzyme displayed high thermostability, retaining more than 90% activity at 60 °C during 120 h and displayed a t 1/2 of 94.5 h and 6.2 h at 70 °C and 80 °C, respectively. The enzyme demonstrated strong resistance toward pepsin and trypsin, and it retained more than 90% residual activity for both enzymes after 1 h treatment. Additionally, the enzyme efficiently hydrolyzed phytate in livestock feed, liberating 15.3 μmol phosphate/mL after 2.5 h of treatment.