Morphological growth pattern of Phanerochaete chrysosporium cultivated on different Miscanthus x giganteus biomass fractions

Background Solid-state fermentation is a fungal culture technique used to produce compounds and products of industrial interest. The growth behaviour of filamentous fungi on solid media is challenging to study due to the intermixity of the substrate and the growing organism. Several strategies are available to measure indirectly the fungal biomass during the fermentation such as following the biochemical production of mycelium-specific components or microscopic observation. The microscopic observation of the development of the mycelium, on lignocellulosic substrate, has not been reported. In this study, we set up an experimental protocol based on microscopy and image processing through which we investigated the growth pattern of Phanerochaete chrysosporium on different Miscanthus x giganteus biomass fractions. Results Object coalescence, the occupied surface area, and radial expansion of the colony were measured in time. The substrate was sterilized by autoclaving, which could be considered a type of pre-treatment. The fastest growth rate was measured on the unfractionated biomass, followed by the soluble fraction of the biomass, then the residual solid fractions. The growth rate on the different fractions of the substrate was additive, suggesting that both the solid and soluble fractions were used by the fungus. Based on the FTIR analysis, there were differences in composition between the solid and soluble fractions of the substrate, but the main components for growth were always present. We propose using this novel method for measuring the very initial fungal growth by following the variation of the number of objects over time. Once growth is established, the growth can be followed by measurement of the occupied surface by the mycelium. Conclusion Our data showed that the growth was affected from the very beginning by the nature of the substrate. The most extensive colonization of the surface was observed with the unfractionated substrate containing both soluble and solid components. The methodology was practical and may be applied to investigate the growth of other fungi, including the influence of environmental parameters on the fungal growth.

Current Status of Cellulosic and Nanocellulosic Materials for Oil Spill Cleanup

Recent developments in the application of lignocellulosic materials for oil spill removal are discussed in this review article. The types of lignocellulosic substrate material and their different chemical and physical modification strategies and basic preparation techniques are presented. The morphological features and the related separation mechanisms of the materials are summarized. The material types were classified into 3D-materials such as hydrophobic and oleophobic sponges and aerogels, or 2D-materials such as membranes, fabrics, films, and meshes. It was found that, particularly for 3D-materials, there is a clear correlation between the material properties, mainly porosity and density, and their absorption performance. Furthermore, it was shown that nanocellulosic precursors are not exclusively suitable to achieve competitive porosity and therefore absorption performance, but also bulk cellulose materials. This finding could lead to developments in cost- and energy-efficient production processes of future lignocellulosic oil spillage removal materials.

Cellulose induced protein 1 (Cip1) from Trichoderma reesei enhances the enzymatic hydrolysis of pretreated lignocellulose

Background Trichoderma reesei is currently the main strain for the commercial production of cellulase. Cellulose induced protein 1 (Cip1) is one of the most abundant proteins in extracellular proteins of T. reesei. Reported literatures about Cip1 mainly focused on the regulation of Cip1 and its possible enzyme activities, but the effect of Cip1 on the enzymatic hydrolysis of lignocellulose and possible mechanism have not still been reported. Results In this study, Cip1 from T. reesei was cloned, expressed and purified, and its effects on enzymatic hydrolysis of several different pretreated lignocellulose were investigated. It was found that Cip1 could promote the enzymatic hydrolysis of pretreated lignocellulose, and the promoting effect was significantly better than that of bovine serum albumin (BSA). And especially for the lignocellulosic substrate with high lignin content such as liquid hot water pretreated corn stover and corncob residue, the promoting effect of Cip1 was even better than that of the commercial cellulase when adding equal amount protein. It was also showed that the metal ions Zn2+ and Cu2+ influenced the promoting effect on enzymatic hydrolysis. The Cip1 protein had no lyase activity, but it could destroy the crystal structure of cellulose and reduce the non-productive adsorption of cellulase on lignin, which partly interpreted the promoting effect of Cip1 on enzymatic hydrolysis of lignocellulose. Conclusion The Cip1 from T. reesei could significantly promote the enzymatic hydrolysis of pretreated lignocellulose, and the promotion of Cip1 was even higher than that of commercial cellulase in the enzymatic hydrolysis of the substrates with high lignin content. This study will help us to better optimize cellulase to improve its ability to degrade lignocellulose, thereby reducing the cost of enzymes required for enzymatic hydrolysis.

The Effect of Biochar-Based Organic Amendments on the Structure of Soil Bacterial Community and Yield of Maize (Zea mays L.)

The taxonomic and functional diversity of bacteria in seven different experimental variants applied to soil under a maize plantation was determined by means of next-generation sequencing and biochemical methods. The aim of the study was to discover differences in the structure of bacteria and the level of soil enzymatic activity (BIF—biochemical index of fertility) after the application of a biofertiliser made of lignocellulosic substrate and biochar containing various microorganisms (algae, mycorrhizal fungi of the Glomus genus or the consortium of Bacillus sp. bacteria). The chemical composition and yield of crops was a measurable indicator of the effectiveness of the fertilisers. The biofertilisers influenced both the structure and the percentage share of individual bacterial operational taxonomic units (OTU). The cultivation of maize also modified qualitative and quantitative changes in the soil bacterial microbiome. A canonical variate analysis (CVA) showed that the soil pH exhibited a minimal positive correlation with the soil enzymatic activity and selected plant parameters, with the exception of the biofertiliser variant with arbuscular mycorrhiza (AM). Moreover, the AM biofertiliser significantly increased the BIF value, the yield of maize seeds and the starch content in the plants. The comprehensive nature of the research allowed for a deepening and systematization of the existing knowledge on the influence of biochar with the addition of selected microorganisms on the biochemical parameters of the soil and the bacterial biodiversity of the soil environment. Additionally, the inclusion of the chemical, sanitary composition and yield of maize in the research brought a measurable view of the changes taking place in the soil and plant environment under the influence of the discussed factor. Apart from the agronomic aspect (integrated crop cultivation—Directive 2009/128/EC) of our study, it was also closely related to environmental protection, as it proved that biochar-based biofertilisers could be an alternative to mineral fertilisation.

Evaluation Of Mechanical, Irradiation And Chemical Pretreatment Lignocelulosic Substrate For Enhanced Methane Production

Lignocellulosic substrate is a resource that contains a locked energy reserve that is normally lost during anaerobic digestion. Lignocellulosic substrate is one of the most abundant sources of organic matter available and yet its energy recovery has much room for improvement. Lignocellulosic substrate has cellular properties that are deemed extremely difficult to degrade due to complexity which is why this energy reserve is never unlocked during anaerobic digestion. There are several successful pretreatment methods that are used to degrade this lignocellulosic substrate and unlock this energy reserve. This paper will focus on the methods that include mechanical, irradiation, chemical and combined pretreatment processes. Analysis is conducted on all the studies that are obtained to compare the successes of the different types of pretreatment processes used. Each of the different listed pretreatment processes have different energy requirements, treatment times, and solvent requirement and are acting to enhancing methane production. The improvement in methane production varies from process to process and study to study creating a need to compile all of this valuable data into this research report. This will help future researchers in navigating the available studies of pretreatment of lignocellulosic substrate for improving methane production.

Evaluation Of Mechanical, Irradiation And Chemical Pretreatment Lignocelulosic Substrate For Enhanced Methane Production

Lignocellulosic substrate is a resource that contains a locked energy reserve that is normally lost during anaerobic digestion. Lignocellulosic substrate is one of the most abundant sources of organic matter available and yet its energy recovery has much room for improvement. Lignocellulosic substrate has cellular properties that are deemed extremely difficult to degrade due to complexity which is why this energy reserve is never unlocked during anaerobic digestion. There are several successful pretreatment methods that are used to degrade this lignocellulosic substrate and unlock this energy reserve. This paper will focus on the methods that include mechanical, irradiation, chemical and combined pretreatment processes. Analysis is conducted on all the studies that are obtained to compare the successes of the different types of pretreatment processes used. Each of the different listed pretreatment processes have different energy requirements, treatment times, and solvent requirement and are acting to enhancing methane production. The improvement in methane production varies from process to process and study to study creating a need to compile all of this valuable data into this research report. This will help future researchers in navigating the available studies of pretreatment of lignocellulosic substrate for improving methane production.

A novel fungal metal-dependent α-l-arabinofuranosidase of family 54 glycoside hydrolase shows expanded substrate specificity

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.

Interaction between clostridium thermocellum ATCC 27405 and thermoanaerobacterium saccharolyticum DSM 7060 on cellulosic and lignocellulosic substrates: substrate attachment, concentration dynamics, and ethanol production

Second generation biofuel research and bioethanol production via consolidated bioprocessing has the potential to become a viable alternative to finite fossil fuel reserves. Further advances have to be made in order to make this biotechnology more economically feasible. The focus of this study was to use cellulotyc C. thermocellum in a consortium with hemicellulotyc T. saccharolyticum to investigate the dynamics of their interaction with respect to cellulosic and lignocellulosic substrate attachment, respective numbers, and extent of solid substrate hydrolysis and desired end product formation. T. saccharolyticum's partial adherence to cotton and switchgrass has demonstrated limited need for substrate colonization and hence reduced competition with C. thermocellum. Real-time PCR analysis indicated that T. saccharolyticum can proliferate under low carbon supplementation, and efficiently utilize the metabolites produced from C. thermocellum's hydrolysis of cotton and switchgrass. The interaction between the two thermophiles on both substrates demonstrated a potential for increased bioethanol production.

Interaction between clostridium thermocellum ATCC 27405 and thermoanaerobacterium saccharolyticum DSM 7060 on cellulosic and lignocellulosic substrates: substrate attachment, concentration dynamics, and ethanol production

Second generation biofuel research and bioethanol production via consolidated bioprocessing has the potential to become a viable alternative to finite fossil fuel reserves. Further advances have to be made in order to make this biotechnology more economically feasible. The focus of this study was to use cellulotyc C. thermocellum in a consortium with hemicellulotyc T. saccharolyticum to investigate the dynamics of their interaction with respect to cellulosic and lignocellulosic substrate attachment, respective numbers, and extent of solid substrate hydrolysis and desired end product formation. T. saccharolyticum's partial adherence to cotton and switchgrass has demonstrated limited need for substrate colonization and hence reduced competition with C. thermocellum. Real-time PCR analysis indicated that T. saccharolyticum can proliferate under low carbon supplementation, and efficiently utilize the metabolites produced from C. thermocellum's hydrolysis of cotton and switchgrass. The interaction between the two thermophiles on both substrates demonstrated a potential for increased bioethanol production.