Overview of Mycelial Fungi - Lignin Destructors

In this work, the following genuses of mycelial fungi, capable of producing ligninolytic enzymes of various actions, were considered:Penicillium, Aspergillus, Fusariumand Altermaria. Fungi of the genus Aspergilluswere capable of producing laccase, manganese peroxidase and lignin peroxidase in the medium. Penicillium mostly produced laccase. Fusariumproduced laccase, aryl alcohol oxidase, manganesedependent peroxidase, manganese-independent peroxidase and lignin peroxidase. Alternariaproduced laccase, lignin peroxidase and manganese peroxidase. The results demonstrated the possibility of using specific substrates in the study of enzyme activity, as well as the influence of some factors introduced into the medium on the synthesis of enzymes. The auxiliary influence of these fungi on the synthesis of ligninolytic enzymes in symbiosis with otherswas considered. Keywords: mycelial fungi, ligninolytic enzymes, Penicillium, Aspergillus, Fusarium, Altermaria

Study of the antibacterial properties of a composition based on chitosan obtained from dead bees Apis Mellifera

The article provides data on the development of a new thickening composition for printing cotton-lye fabric with antibacterial properties based on biodegradable polymers Chitosan synthesized from Apis Mellifera bee dead with CMC with addition of CMC and synthetic hydrolyzed acrylic emulsion. Studied the fungicidal properties of the developed mixed thickener for active dyes used in printing fabrics. As a result of observations, it was revealed that these new thickeners on the basis of exhibit pronounced antimicrobial activity in relation to the micelle fungus Aspergillus terreus. The optical density of the samples shows that these thickeners are resistant to mycelial fungi. Among thickeners, thickeners based on Uzhitan-?MS-HAE, Uzkhitan-CMS have the most pronounced bactericidal activity, and these thickeners are more stable, they can be used the next day and even on the second day for printing mixed fabrics.

Study of the antibacterial properties of a composition based on chitosan obtained from dead bees Apis Mellifera

The article provides data on the development of a new thickening composition for printing cotton-lye fabric with antibacterial properties based on biodegradable polymers Chitosan synthesized from Apis Mellifera bee dead with CMC with addition of CMC and synthetic hydrolyzed acrylic emulsion. Studied the fungicidal properties of the developed mixed thickener for active dyes used in printing fabrics. As a result of observations, it was revealed that these new thickeners on the basis of exhibit pronounced antimicrobial activity in relation to the micelle fungus Aspergillus terreus. The optical density of the samples shows that these thickeners are resistant to mycelial fungi. Among thickeners, thickeners based on Uzhitan-?MS-HAE, Uzkhitan-CMS have the most pronounced bactericidal activity, and these thickeners are more stable, they can be used the next day and even on the second day for printing mixed fabrics.

Features of antifungal therapy during long-lasting infectious process: a clinical case of fungal keratitis and profile of antifungal sensitivity based on assessing biofilm formation

Among infectious diseases, opportunistic mycoses hold a special place. There has been accumulating a lot of evidence regarding the clinical and epidemiological aspects of infection caused by Fusarium spp., which global incidence rate among microbial keratitis ranges from 2 to 40% depending on the geographical location of the country. Colonizing mucous membranes, fungi can exist not only in the form of plankton, but form biofilms after surface attachment, which leads to elevated resistance to multiple antifungal agents. Here we describe a clinical case of fungal keratitis due to Fusarium solani by determining profile of the antifungal sensitivity for isolated fungal strains, by taking into account their potential for biofilm formation. We used an F. solani culture isolated from the patient as well as F. solani test culture obtained from the Russian National Collection of Microorganisms. While determining the sensitivity of fungal planktonic cultures to antifungal agents from the azole group (fluconazole, voriconazole), amphotericin B and terbinafine, it was revealed that antimycotics amphotericin B and voriconazole exerted a marked antifungal activity against clinical isolate, whereas the plankton F. solani test culture was more sensitive to all groups of antifungal agents. Due to a long-lasting progressive course of the infectious process and the high biofilm-forming ability of the clinical strain F. solani, the activity of antifungal agents on biofilm cells was modeled and examined in vitro. It was shown that regarding to the fungal biofilms, value of the minimally inhibitory concentration exceeded those for planktonic cultures by 100-fold. The mechanisms of action for antifungal agents on vital parameters of fungal cell structures were analyzed by using confocal laser scanning microscopy after staining samples with propidium iodide and acridine orange for 15 min to detect changes between intact and damaged cell surface. It was found that within the biofilm fungal cells preserved viability even after exposure to high concentrations of antifungals. In addition, despite the fungicidal drug activity at substantial concentrations acting on the biofilm cell membrane, the cell nuclei remained viable. Owing to the presence ot the mechanism of resistance in mycelial fungi shown in the study, it is necessary to take into account and investigate characteristics of biofilms in terms of drug sensitivity that will allow to optimize a choice of antimicrobial therapy.

Study of the efficiency of the inhibitory effect of antimicrobial preparations in the production of sugar substances

This article presents the relevance of the issue of inhibition of microbiological processes at different stages of processing of sugar-containing raw materials, in particular ensuring the microbiological purity of juices and syrups in the production of sugar substances. Information on the composition of microbiota contaminating raw materials in the production of beet sugar, raw cane sugar, food syrups from sugar sorghum is analyzed. Experimental data on the evaluation of the effectiveness of a number of antimicrobial preparations in terms of growth retardation of pure cultures of microorganisms and the effect of disinfection during the introduction of preparations are presented. The greatest danger in production is caused by the development of spore-forming and mucus-forming bacteria, which led to the choice of research objects. Thus, the effect of antimicrobial preparations on microorganisms: mesophilic bacteria Bacillus subtilis, B. megatherium, thermophilic bacteria B. stearothermophilus, mucus-forming bacteria of the genus Leuconostos, was investigated. In addition, the effect of antimicrobials on mycelial fungi of the genus Aspergillus was studied. Based on the conducted experimental studies, the range of costs of the studied antimicrobial preparation for the suppression of contaminating microflora in the production of sugar and food syrups from vegetable raw materials was determined

DISTRIBUTION OF MYCELIAL FUNGI IN WATER BODIES OF THE VOLGA REGION

Mycological analysis of water samples from the rivers of the Volga region showed that, in water samples taken from rivers in the territory of the Republic of Tatarstan, fungi of the genus As-pergillus were isolated in 15 % of samples, Cladosporium – 25 %, Fusarium – 21 %, Penicillium – 13 %, Mucor – 2 %, Rodotorula – 24 %. Fungi of the genus Aspergillus – 23 %, Cladosporium – 31 %, Fusarium – 25 %, Penicillium – 18 %, Trichoderma – 14 %, Mucor – 12 % samples were sown in water samples taken from the water bodies of the Republic of Mari-El. In the Republic of Chu-vashia, fungi of the genus Aspergillus – 23 %, Cladosporium – 17 %, Fusarium – 20 %, Penicillium – 22 %, Mucor – 8 % of water samples were isolated. Thus, an increased ammonium content was observed in water samples from the Mesha rivers – 2,08±0,42 mg/dm3, the Volga – 1,04±0,21 mg/dm3, and the Komarovo reservoir – 1,98±0,40 mg/dm3, with the value of the maximum permis-sible concentration for fishery purposes – 0,51 mg/dm3. An increased amount of sulfates in the summer season was observed in the Republic of Tatarstan in water samples from Lake Kaban – 140,0±15 with the value of the maximum permissible concentration for fishery purposes – 100 mg/dm3, in the same samples, the maximum water hardness was recorded – 10,6±1,59 0J.

Avaliação do Efeito do Extrato Etanólico de Piper umbellatum L. no Controle Alternativo de Rhizoctonia solani e Macrophomina phaseolina

Objetivou-se, neste trabalho, investigar o potencial do extrato da planta Piper umbellatum (Sin. Piper umbellata L.) no crescimento micelial de Rhizoctonia solani e Macrophomina phaseolina. Para avaliação das habilidades fungicida e ou fungistática, os fungos fitopatogênicos foram crescidos previamente em meio de cultura BDA (batata dextrose ágar), tendo sido realizado o teste de crescimento micelial, em meio de cultura BDA nas concentrações de 800, 1200, 1600, 2000 e 2400 µg 100 mL-1. Foram vertidos 10 mL de meio das diferentes concentrações em placas de Petri, com quatro repetições para cada concentração. A avaliação do crescimento micelial para todos os patógenos foi realizada por medidas diárias do diâmetro das colônias. Na prospecção fitoquímica do extrato etanólico de P. umbellatum foi detectada a presença majoritária de compostos fenólicos (100%), seguido dos flavonoides, esteroides e alcaloides (75%), os taninos, triterpenos e açúcares redutores (50%) e com menor frequência as saponinas (25%). As concentrações testadas não inibiram o crescimento micelial dos fungos, no entanto se observou que houve interferência no desenvolvimento da colônia de R. solani, pois não foi observada a formação de micro escleródios, estruturas estas formadas na testemunha e em função da presença de metabólitos secundários no extrato que podem apresentar atividade antifúngica, é recomendável a continuação do estudo fitoquímico de P. umbellatum, para isolamento e identificação de substâncias responsáveis pela atividade e determinar suas frações ativas, visando o controle de agentes fitopatogênicos. Palavras-chave: Plantas Fungicidas. Piperaceae. Estratos Vegetais. Rhizoctonia solani; Macrophomina phaseolina. Abstract The objective of this work was to investigate the potential of Piper umbellatum (Sin. Piper umbellata L.) plant extract on the mycelial growth of Rhizoctonia solani and Macrophomina phaseolina. To evaluate fungicidal and or fungistatic abilities, phytopathogenic fungi were previously grown in BDA culture medium (potato dextrose agar), mycelial growth test was performed in BDA culture medium at concentrations of 800, 1200, 1600, 2000 and 2400 µg 100 mL -1. 10 mL of medium of the different concentrations were poured into Petri dishes, with four replicates for each concentration. Mycelial growth evaluation for all the pathogens was performed by daily measurements of colony diameter. Phytochemical prospecting of P. umbellatum ethanolic extract showed the presence of phenolic compounds (100%), followed by flavonoids, steroids and alkaloids (75%), tannins, triterpenes and reducing sugars (50%) and less frequently. the saponins (25%). The tested concentrations did not inhibit the mycelial fungi growth, however, it was observed that there was interference in the development of R. solani colony, as the formation of micro sclerodes, structures formed in the control was not observed and due to the presence of secondary metabolites. In the extract that may present antifungal activity, the continuation of the phytochemical study of P. umbellatum is recommended for isolation and identification of substances responsible for the activity and to determine their active fractions, aiming at the control of phytopathogenic agents. Keywords: Fungicidal plants; Piperaceae; Plant extracts; Rhizoctonia solani; Macrophomina phaseolina.

Those who can don’t want to, and those who want to can’t: eco-evolutionary constraints to decomposition explain soil carbon persistence

Reliable manipulation of soil organic matter (SOM) – a necessity for optimal land management – is constrained by our limited mechanistic understanding of SOM formation. Here we add to existing frameworks a novel mechanistic element that may underpin SOM dynamics, based on evolutionary-ecological rather than chemical or physical limitations to decomposition. We argue that decomposition of some substrates may be ecologically constrained in mycelial fungi, evolutionarily constrained in co-operating bacteria, and geometrically constrained in unicellular microbes. We describe and test a mathematical model based on our framework, providing a proof-of-concept that substrate can plausibly be spared decomposition and accumulate even when it is physically and chemically accessible. Our framework can explain a variety of SOM dynamics, including priming and the suppression of decomposition by nitrogen addition, as well as the typical composition of SOM. An augmented mechanistic framework for understanding SOM dynamics can help guide targeted empirical study, which in turn can contribute to more optimised land management.

Toxicity of new fungicides for eukaryotic microorganisms isolated from the gut of the food-important vegetable pollinator Bombus terrestris L.

Currently, there is a trend in decreasing of the number of pollinators, which is already a matter of food security. Bumblebees Bombus terrestris L. are economically important pollinators of vegetables and other agricultural crops. Recently, it has been suggested that the synergistic effect of pesticides and diseases that affect pollinators contributes to a sharp decline in the number of pollinators. In this work, we investigated the effect of new biodegradable fungicides on eukaryotic microorganisms Penicillium commune and Rhodotorula mucilaginosa isolated from the gut of Bombus terrestris L. larvae. It was shown that the new fungicides studied can inhibit the growth of both mycelial eukaryotic microorganisms and yeast eukaryotic microorganisms. Among the studied substances, the most effective was fungicide 2. The studied substances are selectively toxic only for eukaryotic microorganisms and do not have a toxic effect on animals, in particular insects, and can be used to treat insect pollinator infections caused by fungal microorganisms. It was noted that the new fungicides are more toxic to yeast than to mycelial fungi.