scholarly journals Isolation, screening and identification of ligno-cellulolytic fungi from northern central Morocco

2019 ◽  
Author(s):  
Hasna Nait M’barek ◽  
Behnam Taidi ◽  
Touhami Smaoui ◽  
Mohamed Ben Aziz ◽  
Aouatef Mansouri ◽  
...  
Keyword(s):  
Filamentous Fungi ◽  
Extracellular Enzymes ◽  
Biomass Conversion ◽  
Wood Decay ◽  
Local Environment ◽  
Mucor Circinelloides ◽  
Cellulolytic Enzymes ◽  
Process Conditions ◽  
Molecular Technique ◽  
Screening And Identification

Description of the subject. Extracellular enzymes from filamentous fungi are increasingly used in eco-friendly biotransformation processes. Their relevant technological role and their stability towards extreme process conditions make of them the first sustainable solution for the elaboration of bio-based products from biomass conversion. Objectives. This paper describes the isolation of filamentous fungi from decaying plant material in the region of Meknes (northern central Morocco) and the assessment of their ability to breakdown lignocellulose. The objective is to select performant fungi with enzymatic machinery adapted to local environment and with potential for the breakdown of the regional specific lignocellulosic by-products into potentially high-value molecules. Method. Cereals, decaying wood, olive-pomace and -pulp and their composts were used to isolate lignocellulolytic fungi. One hundred twenty-seven pure strains were isolated and screened at 25 °C on selective media with cellulose or lignin as the sole carbon source. Performant strains were validated for the production of ligno-cellulolytic enzymes and identified using molecular technique. Results. Twenty-eight fungi had mycelial diameter on cellulose ≥ 6 cm and cellulolytic index ≥ 0.9. Twenty-two strains had the same profile on lignin medium. The production of endoglucanase, lignin peroxidase and manganese peroxidase enzymes was confirmed in performant strains using qualitative assay and molecular identification revealed that the best performing fungi were Mucor circinelloides, Mucor racemosus, Penicillium brasilianum, Penicillium crustosum, Paecilomyces sp., Fusarium oxysporum, Fusarium solani, Aspergillus fischeri, Curvularia spicifera, Humicola grisea, Trichoderma atroviride and Cosmospora viridescens. Measurement of ligno-cellulolytic activities revealed that Penicillium and Fusarium strains mainly from wood decay and compost had the best profiles among performing strains. Conclusions. Isolated fungi are high decomposers of biomass and represent a prominent solution to develop green bioprocesses in the region.

Microscopic fungi of lithobiont communities of Argentine Islands Region: Data from the 22nd Ukrainian Antarctic Expedition

2020 ◽  
Vol 62 (1-2) ◽  
pp. 49-68
Author(s):  
T. O. Kondratiuk ◽  
T. V. Beregova ◽  
I. Yu. Parnikoza ◽  
S. Y. Kondratyuk ◽  
A. Thell
Keyword(s):  
Filamentous Fungi ◽  
Mucor Circinelloides ◽  
Biologically Active Substances ◽  
Biologically Active ◽  
Microscopic Fungi ◽  
Rhodotorula Rubra ◽  
Yeast Fungi ◽  
Antarctic Expedition ◽  
Geomyces Pannorum ◽  
Active Substances

The identification of the diversity of microscopic fungi of lithobiont communities of the Argentine Islands in specimens collected during the 22nd Ukrainian Antarctic Expedition was the purpose of this work. Samples of rock, soil, mosses and lichens of rock micro-habitats of “Crustose lichen sub-formation and fruticose lichen and moss cushion sub-formation” were used in the work. These samples were used for extracting and cultivation of filamentous fungi on dense nutrient media. Determination of physiological and biochemical characteristics and identification of yeast-like fungi were performed using a microbiological analyser ‘Vitek-2’ (‘Bio Merieux’, France). Cultivation of microorganisms was carried out at temperatures from +2 to +37 °C. In results cultures of microscopic fungi of Zygomycota (Mucor circinelloides), Ascomycota (species of the genera cf. Tlielebolus, Talaromyces), representatives of the Anamorphic fungi group (Geomyces pannorum, species of the genera Alternaria, Acremonium, Aspergillus, Penicillium, and Cladosporium) were isolated from Antarctic samples. Microscopic fungi Penicillium spp. were dominated after the frequency in the studied samples (54.5%). Rhodotorula rubra and Candida sp. among isolated yeast fungi, and dark pigmented fungi represented by Aureobasidium pulhdans and Exophiala spp. were identified. The biological properties of a number of isolated fungi (the potential ability to synthesise important biologically active substances: melanins, carotenoids, lipids) are characterised. Mycobiota of rock communities of Argentine Islands is rich on filamentous and yeast fungi similarly to other regions of Antarctica. A number of fungi investigated are potentially able to synthesise biologically active substances. The dark pigmented species of the genera Cladosporium, Exophiala, Aureobasidium pulhdans, capable of melanin synthesis; ‘red’ yeast Rhodotorula rubra (carotenoid producers and resistant to toxic metals); Mucor circinelloides and Geomyces pannorum, lipid producers, are among these fungi. Yeast-like fungi assimilated a wide range of carbohydrates, which will allow them to be further used for cultivation in laboratory and process conditions. The collection of technologically promising strains of microorganisms, part of the Culture Collection of Fungi at Taras Shevchenko National University of Kyiv (Ukraine), is updated with isolated species (strains) of filamentous fungi and yeast – potential producers of biologically active substances, obtained within this study.

Repeated Elements in Filamentous Fungi with a Focus on Wood-Decay Fungi

2013 ◽  
pp. 21-40 ◽  
Author(s):  
Claude Murat ◽  
Thibaut Payen ◽  
Denis Petitpierre ◽  
Jessy Labbé
Keyword(s):  
Filamentous Fungi ◽  
Wood Decay ◽  
Decay Fungi ◽  
Wood Decay Fungi

Regulation of lipid accumulation in oleaginous micro-organisms

2002 ◽  
Vol 30 (6) ◽  
pp. 1047-1050 ◽  
Author(s):  
C. Ratledge
Keyword(s):  
Filamentous Fungi ◽  
Lipid Accumulation ◽  
Fatty Acid Synthase ◽  
Sole Source ◽  
Mucor Circinelloides ◽  
Storage Lipids ◽  
Atp:Citrate Lyase ◽  
The Stability ◽  
Micro Organisms ◽  
Single Cell Oils

A small number of eukaryotic micro-organisms, the oleaginous species, can accumulate triacylglycerols as cellular storage lipids, sometimes up to 70% of the biomass. Some of these lipids, particularly those containing high proportions of polyunsaturated fatty acids of nutritional and dietary importance, are now in commercial production; these are known as single-cell oils. The biochemistry of lipid accumulation has been investigated in yeasts and filamentous fungi and can now be described in some detail: lipid accumulation is triggered by cells exhausting nitrogen from the culture medium, but glucose continues to be assimilated. Activity of isocitrate dehydrogenase within the mitochondrion, however, now slows or even stops due to the diminution of AMP within the cells. This leads to the accumulation of citrate, which is transported into the cytosol and cleaved to acetyl-CoA by ATP:citrate lyase, an enzyme that does not occur in non-oleaginous species. This enzyme is therefore essential for lipid accumulation. The presence of this enzyme does not, however, explain why different species of oleaginous micro-organisms have different capacities for lipid accumulation. The extent of lipid accumulation is considered to be controlled by the activity of malic enzyme (ME), which acts as the sole source of NADPH for fatty acid synthase (FAS). If ME is inhibited, or genetically disabled, then lipid accumulation is very low. There is no general pool of NADPH which can otherwise be used by FAS. The stability of ME is therefore crucial and it is proposed that ME is physically attached to FAS as part of the lipogenic metabolon. ME activity correlates closely with lipid accumulation in two filamentous fungi, Mucor circinelloides and Mortierella alpina. When ME ceases to be active, lipid accumulation also stops. No other enzyme activity shows such a correlation.

Catalytic Conversion of Oil Palm Fronds to Levulinic Acid in Ionic Liquid

2014 ◽  
Vol 625 ◽  
pp. 361-365 ◽  
Author(s):  
Nur Aainaa Syahirah Ramli ◽  
Nor Aishah Saidina Amin
Keyword(s):  
Ionic Liquid ◽  
Oil Palm ◽  
Levulinic Acid ◽  
Biomass Conversion ◽  
Catalyst Loading ◽  
Process Conditions ◽  
Acid Yield ◽  
Hy Zeolite ◽  
Oil Palm Fronds ◽  
Palm Fronds

Conversion of oil palm fronds (OPF) to levulinic acid (LA) over Fe/HY zeolite catalyst in BMIM[Br] ionic liquid has been investigated in this study. The optimization of OPF conversion reported 24.7% levulinic acid yield at 153 °C, 5.9 h, 0.96 g and 1.1 g of reaction temperature, reaction time, OPF loading and catalyst loading, respectively. The results indicated that BMIM[Br] could disrupt the covalent linkages in the OPF structures and dissolved the hollocellulose. This allowed the hollocellulose chains, accessible to the chemical transformation, to react and produce LA in presence of the Fe/HY catalyst. This study demonstrated that the combination of Fe/HY catalyst and BMIM[Br] has the potential to be applied for biomass conversion to LA under adequate process conditions.

Fractionation and identification of cellulases and other extracellular enzymes produced by Sporotrichum (Chrysosporium) thermophile during growth on cellulose or cellobiose

1983 ◽  
Vol 29 (9) ◽  
pp. 1071-1080 ◽  
Author(s):  
G. Canevascini ◽  
D. Fracheboud ◽  
H. Meier
Keyword(s):  
Extracellular Enzymes ◽  
Polyacrylamide Gel Electrophoresis ◽  
Reducing Power ◽  
Extracellular Enzyme ◽  
Cellulolytic Enzymes ◽  
Crystalline Cellulose ◽  
Concomitant Increase ◽  
Amorphous Cellulose ◽  
Enzymatic Action ◽  
Isoelectric Points

The extracellular enzyme proteins secreted by Sporotrichum (Chrysosporium) thermophile, ATCC 42 464, upon growth on cellulose or cellobiose, were separated by polyacrylamide gel electrophoresis and electrofocusing into different fractions which were then analyzed with respect to their enzymatic character to identify the cellulolytic enzymes. A positive reaction against carboxymethylcellulose azure (CMC azure) was taken as evidence for an endo-acting cellulase, whereas the criterion for the presence of an exo-cellulase was a negative reaction with CMC azure and a concomitant increase in reducing power upon action of any kind of cellulose. With this procedure, four main cellulolytic enzymes were detected: three endo-cellulases, named endo-cellulases I, II, and III (with corresponding isoelectric points 5.1, 4.2, 5.7), and an exo-cellulase (isoelectric point 4.7). With respect to their enzymatic action on amorphous cellulose, endo-cellulases I and III were isofunctional, releasing cellobiose and cellodextrins as hydrolytic products, whereas endo-cellulase II was found to produce additionally some glucose. Endo-cellulases I and III were also able to attack native (crystalline) cellulose like filter paper or Avicel, but endo-cellulase II could not and thus behaved as a true carboxymethylcellulase. The rate of formation of endo-cellulase I during growth was distinctly superior from that of the other cellulases so that the proportion of the activity due to endo-cellulase. I compared with that due to the others constantly increased during the culture.

scholarly journals Contrasting demographic histories revealed in two invasive populations of the dry rot fungus Serpula lacrymans

2021 ◽  
Author(s):  
Inger Skrede ◽  
Claude Murat ◽  
Jaqueline Hess ◽  
sundy Maurice ◽  
Jørn Henrik Sønstebø ◽  
...  
Keyword(s):  
Built Environment ◽  
Protein Modification ◽  
Intracellular Transport ◽  
Wood Decay ◽  
Local Environment ◽  
European Population ◽  
Indoor Environments ◽  
Dry Rot ◽  
Genomic Analyses ◽  
Serpula Lacrymans

Globalization and international trade have impacted organisms around the world leading to a considerable number of species establishing in new geographic areas. Many organisms have taken advantage of human-made environments, including buildings. One such species is the dry rot fungus Serpula lacrymans, which is the most aggressive wood-decay fungus in indoor environments in temperate regions. By using population genomic analyses of 36 full genome sequenced isolates, we revealed that isolates from Europe and Japan are highly divergent and that these populations split 3,000 - 19,000 generations ago, probably predating human influence. Approximately 250 generations ago, the European population went through a tight bottleneck, likely corresponding to the time it colonized the built environment. Moreover, evidence of admixture between European and Japanese populations was shown in an isolate from New Zealand. Genomic analyses revealed that low differentiation appeared in genes with functions related to of growth and intracellular transport, possibly important to its ability to effectively decay large substrates. These functions may have enabled both populations to independently establish in the human-made environment. Further, selective sweep analyses identified rapid changes in genes possibly related to decay of various substrates in Japan and in genes involved DNA replication and protein modification in Europe. These two fungal populations were preadapted to the built environment, but have more recently and independently adapted to their local environment.

Enhancement of biological fermented sludge dewaterability by inoculation of filamentous fungi Mucor circinelloides XY-Z and Penicillium oxalicum LY-1

2019 ◽  
Vol 37 (13) ◽  
pp. 1678-1687 ◽  
Author(s):  
Yingying Li ◽  
Liming Dong ◽  
Yangyang Li ◽  
Xinyuan Zheng ◽  
Chen Zhang ◽  
...  
Keyword(s):  
Filamentous Fungi ◽  
Mucor Circinelloides ◽  
Penicillium Oxalicum ◽  
Sludge Dewaterability

scholarly journals Cultivable cellulolytic fungi isolated from the gut of Amazonian aquatic insects

2020 ◽  
Vol 50 (4) ◽  
pp. 346-354
Author(s):  
Enide Luciana BELMONT-MONTEFUSCO ◽  
Lorena NACIF-MARÇAL ◽  
Enedina Nogueira de ASSUNÇÃO ◽  
Neusa HAMADA ◽  
Carlos Gustavo NUNES-SILVA
Keyword(s):  
Filamentous Fungi ◽  
Aquatic Insects ◽  
Extracellular Enzymes ◽  
Agar Medium ◽  
Synthetic Medium ◽  
Aquatic Insect ◽  
Cellulolytic Activity ◽  
Insect Larvae ◽  
Potato Dextrose Agar Medium ◽  
Aquatic Insect Larvae

ABSTRACT Filamentous fungi have been targeted by bioprospecting studies because they are effective producers of extracellular enzymes that can potentially be used by the bioindustry. In this study, we isolated filamentous fungi from the guts of Amazonian aquatic insect larvae to evaluate their cellulolytic activity. We collected 69 larvae of shredder insects of three genera: Phylloicus (Trichoptera: Calamoceratidae), Triplectides (Trichoptera: Leptoceridae) and Stenochironomus (Diptera: Chironomidae) in ten streams from a protected area in the central Brazilian Amazon. Production of mycelia was elaborated in PDA (Potato Dextrose Agar) medium. The isolates were transferred to a synthetic medium with carboxymethyl cellulose, and Congo red was used to determine the enzymatic index. The hydrolysis halo, indicating the production of cellulases, was observed in 175 fungal isolates (70% of the total), of which 25 had an enzymatic index ≥ 2.0 and belonged to seven fungal genera. The fungal taxa Cladosporium, Gliocephalotrichum, Penicillium, Pestalotiopsis, Talaromyces, Trichoderma and Umbelopsis were isolated from guts of Phylloicus, Triplectides and Stenochironomus, which are traditionally used in biotechnological applications. Our results indicate the cellulolytic potential of fungi associated with the guts of aquatic Amazonian insects.

scholarly journals Insect cellulolytic enzymes: Novel sources for degradation of lignocellulosic biomass

2015 ◽  
Vol 7 (2) ◽  
pp. 625-630 ◽  
Author(s):  
Monica Sachdeva Taggar
Keyword(s):  
Lignocellulosic Biomass ◽  
Fossil Fuels ◽  
Biomass Conversion ◽  
Global Climate ◽  
Significant Proportion ◽  
Cellulolytic Enzymes ◽  
Cellulose Digestion ◽  
Potential Source ◽  
Hind Gut ◽  
Enzymatic Depolymerization

Alternative and renewable fuels derived from lignocellulosic biomass offer the potential to reduce our dependence on fossil fuels and mitigate global climate change. Cellulose is one of the major structural components in all lignocellulosic wastes and enzymatic depolymerization of cellulose by cellulases is an essential step in bio-ethanol production. Wood-degrading insects are potential source of biochemical catalysts for converting wood lignocellulose into biofuels. Cellulose digestion has been demonstrated in more than 20 insect families representing ten distinct insect orders. Termite guts been have considered as the “world’s smallest bioreactors” since they digest a significant proportion of cellulose (74-99%) and hemicellulose (65-87%) components of lignocelluloses they ingest. The lower termites harbor protistan symbionts in hindgut whereas higher termites lack these in the hind gut. Studies on cellulose digestion in termites and other insects with reference to ligno-cellulose degrading enzymes have been well focused in this review. The studies on insect cellulolytic systems can lead to the discovery of a variety of novel biocatalysts and genes that encode them, as well as associated unique mechanisms for efficient biomass conversion into biofuels.

scholarly journals Analysis of operational issues in hydrothermal liquefaction and supercritical water gasification processes: a review

2021 ◽  
Author(s):  
Niloufar Ghavami ◽  
Karhan Özdenkçi ◽  
Gabriel Salierno ◽  
Margareta Björklund-Sänkiaho ◽  
Cataldo De Blasio
Keyword(s):  
Supercritical Water ◽  
Biomass Conversion ◽  
Hydrothermal Liquefaction ◽  
Production Costs ◽  
Process Conditions ◽  
Operation Conditions ◽  
High Production ◽  
Supercritical Water Gasification ◽  
Operational Issues ◽  
Conversion Technologies

AbstractBiomass is often referred to as a carbon–neutral energy source, and it has a role in reducing fossil fuel depletion. In addition, biomass can be converted efficiently into various forms of biofuels. The biomass conversion processes involve several thermochemical, biochemical, and hydrothermal methods for biomass treatment integration. The most common conversion routes to produce biofuels include pyrolysis and gasification processes. On the other hand, supercritical water gasification (SCWG) and hydrothermal liquefaction (HTL) are best suitable for converting biomass and waste with high moisture content. Despite promising efficiencies, SCWG and HTL processes introduce operational issues as obstacles to the industrialization of these technologies. The issues include process safety aspects due to operation conditions, plugging due to solid deposition, corrosion, pumpability of feedstock, catalyst sintering and deactivation, and high production costs. The methods to address these issues include various reactor configurations to avoid plugging and optimizing process conditions to minimize other issues. However, there are only a few studies investigating the operational issues as the main scope, and reviews are seldomly available in this regard. Therefore, further research is required to address operational problems. This study reviews the main operational problems in SCWG and HTL. The objective of this study is to enhance the industrialization of these processes by investigating the operational issues and the potential solutions, i.e., contributing to the elimination of the obstacles. A comprehensive study on the operational issues provides a holistic overview of the biomass conversion technologies and biorefinery concepts to promote the industrialization of SCWG and HTL.

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