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Antarctica harbors a microbial diversity still poorly explored and of inestimable biotechnological value. Cold-adapted microorganisms can produce a diverse range of metabolites stable at low temperatures, making these compounds industrially interesting for biotechnological use. The present work investigated the biotechnological potential for antimicrobial and antitumor activity of filamentous fungi and bacteria isolated from marine sediment samples collected at Deception Island, Antarctica. A total of 89 microbial isolates were recovered from marine sediments and submitted to an initial screening for L-glutaminase with antitumoral activity and for antimicrobial metabolites. The isolates Pseudogymnoascus sp. FDG01, Pseudogymnoascus sp. FDG02, and Penicillium sp. FAD33 showed potential antiproliferative action against human pancreatic carcinoma cells while showing no toxic effect on non-tumor cells. The microbial extracts from unidentified three bacteria and four filamentous fungi showed antibacterial activity against at least one tested pathogenic bacterial strain. The isolate FDG01 inhibited four bacterial species, while the isolate FDG01 was active against Micrococcus luteus in the minimal inhibitory concentration of 0.015625 µg mL -1. The results pave the way for further optimization of enzyme production and characterization of enzymes and metabolites found and reaffirm Antarctic marine environments as a wealthy source of compounds potentially applicable in the healthcare and pharmaceutical industry.

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Microorganisms that inhabit the cold Antarctic environment can produce ligninolytic enzymes potentially useful in bioremediation. Our study focused on characterizing Antarctic bacteria and fungi from marine sediment samples of King George and Deception Islands, maritime Antarctica, potentially affected by hydrocarbon influence, able to produce enzymes for use in bioremediation processes in environments impacted with petroleum derivatives. A total of 168 microorganism isolates were obtained: 56 from sediments of King George Island and 112 from Deception Island. Among them, five bacterial isolates were tolerant to cell growth in the presence of diesel oil and gasoline and seven fungal were able to discolor RBBR dye. In addition, 16 isolates (15 bacterial and one fungal) displayed enzymatic emulsifying activities. Two isolates were characterized taxonomically by showing better biotechnological results. Psychrobacter sp. BAD17 and Cladosporium sp. FAR18 showed pyrene tolerance (cell growth of 0.03 g mL-1 and 0.2 g mL-1) and laccase enzymatic activity (0.006 UL-1 and 0.10 UL-1), respectively. Our results indicate that bacteria and fungi living in sediments under potential effect of hydrocarbon pollution may represent a promising alternative to bioremediate cold environments contaminated with polluting compounds derived from petroleum such as polycyclic aromatic hydrocarbons and dyes.

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The search for sustainable development has increased interest in the improvement of technologies that use renewable energy sources. One of the alternatives in the production of renewable energy comes from the use of waste including urban solids, animal excrement from livestock, and biomass residues from agro-industrial plants. These materials may be used in the production of biogas, making its production highly sustainable and environmentally friendly. The present study aimed to evaluate the cultivated and uncultivated microbial community from a substrate (starter) used as an adapter for biogas production in anaerobic digestion processes. 16S rDNA metabarcoding revealed the domain of bacteria belonging to the phyla Firmicutes, Bacteroidota, Chloroflexi and Synergistota. The methanogenic group was represented by the phyla Halobacterota and Euryarchaeota. Through 16S rRNA sequencing of isolates recovered from the starter culture, the genera Rhodococcus (Actinobacteria phylum), Vagococcus, Lysinibacillus, Niallia, Priestia, Robertmurraya, Proteiniclasticum (Firmicutes phylum), and Luteimonas (Proteobacteria phylum) were identified, genera that were not observed in the metabarcoding data. The volatile solids, volatile organic acids, and total inorganic carbon reached 659.10 g kg-1, 717.70 g kg-1, 70,005.0 g kg-1, respectively. The cultured groups are involved in the metabolism of sugars and other compounds derived from lignocellulosic material, as well as in anaerobic methane production processes. The results demonstrate that culture-dependent approaches, such as isolation and sequencing, and culture-independent studies, such as the Metabarcoding approach, are complementary methodologies that, when integrated provide robust and comprehensive information about the microbial communities involved in processes of the production of biogas in anaerobic digestion processes.

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The inappropriate disposal of toxic compounds generated by industrial activity has been impacting the environment considerably. Microbial communities inhabiting contaminated sites may represent interesting ecological alternatives for the decontamination of environments. The present work aimed to investigate the fungal diversity and its functionality contained in stream sediments with industrial waste contaminated with heavy metals by using metagenomic approach. A total of 12 fungal orders were retrieved from datasets and, at phylum level, Ascomycota was the most abundant, followed by Basidiomycota, Chytridiomycota and Blastocladiomycota. Higher abundance of sequences was encountered within the less contaminated site, while the lower abundance was found in the sample with the higher contamination with lead. Gene sequences related to DNA repair and heavy metals biosorption processes were found in the four samples analyzed. The genera Aspergillus and Chaetomium, and Saccharomycetales order were highly present within all samples, showing their potential to be used for bioremediation studies. The present work demonstrated the importance of using the metagenomic approach to understand the dynamics and the possible metabolic pathways associated with fungal communities related to environmental samples containing heavy metals, as well as evidenced the importance of improving culturomics techniques for isolating strains with potential application in bioremediation processes of environments contaminated with heavy metals.

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Urban waste (UW) has caused a series of problems regarding its management. UW comprises domestic, hospital and industrial residues, which makes the destination of this waste a matter of concern, as it may contain a variety of highly toxic environmental polluters. Deactivated dumps can represent sources of contamination of the environment that surround these deposits, harming rivers and inhabiting organisms. Knowledge of the microbial profile of water bodies that can be affected by these toxic residues is essential for the development of alternatives and improvements in treatments applied in rivers and streams. In this sense, this work aimed to analyze the microbial community present in sediments of the Arroio Dourado stream in the municipality of Foz do Iguaçu, a stream located near a deactivated open-air dump. 16S rDNA metabarcoding suggested the dominance of acidogenic bacteria belonging to Acidobacteriota phylum, followed by less abundant phyla Actinobacteriota, Myxococcota, Chloroflexi and a small community of sulfate reducers (Desulfobacteriota). However, more than 50% of amplicon sequence variants (ASVs) were not taxonomically classified. In addition, an expressive abundance was attributed to the genus Anaeromyxobacter, a metabolically versatile group, which can thrive in the presence of polluting compounds present in the deactivated landfill. Thus, a possible stream treatment process can be developed. In addition, culture media can be developed for the recovery of taxonomic groups identified involved in the biodegradation of organic compounds. The results presented expand the knowledge of bacterial diversity in sediment samples recovered from the Arroio Dourado stream.

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The need for more effective drugs for the treatment of infectious diseases as well as for general applications including wound healing and burn surgery, has guided efforts for the discovery of new compounds of medical interest. Microorganisms found in textile industrial waste have the ability to produce a variety of enzymes and/or secondary metabolites including molecules of pharmaceutical interest. The present work investigated the biotechnological potential of filamentous fungi isolated from textile industry wastewater for the production of collagenase and antimicrobial metabolites. From 28 isolates assayed, Sarocladium sp. ITF33 showed specific collagenolytic activity with values of 7.62 and 9.04 U mg-1 for the intracellular and extracellular fractions, respectively. The isolate Penicillium sp. ITF28 showed the best antimicrobial activity, reaching MIC ranging from 1.0 to 0.0625 mg mL-1 against five pathogenic bacteria. Molecular analyzes suggest that the isolate Sarocladium sp. ITF 33 can be considered a species not yet described. The results of the present work encourage studies of characterization and purification of the enzymes and secondary metabolites produced by the isolates found aiming future applications in the medical and pharmaceutical fields.

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O glifosato é um herbicida amplamente utilizado. A Organização Mundial da Saúde (OMS) reclassificou o glifosato como "provavelmente cancerígeno a humanos". A remoção do glifosato do ambiente pode ser realizada por ação enzimática microbiana. O presente trabalho enfocou o isolamento de microrganismos do solo capazes de tolerar glifosato como única fonte de carbono. As células foram isoladas em meio de cultivo mínimo suplementado com glifosato. Foram isoladas 17 bactérias, 14 fungos e 1 levedura. Foi verificada a produção da biomassa microbiana na presença e na ausência do glifosato. Um fungo (F3) e uma levedura (L1) foram selecionados após teste de tolerância ao glifosato em meio líquido. Os microrganismos toleraram o glifosato, entretanto, o metabolismo foi afetado pelo herbicida, comparado ao controle sem glifosato. Estatisticamente, o tempo de crescimento apresentou diferenças significativas. Microrganismos eucarióticos isolados de solo com glifosato são tolerantes ao composto e podem ser úteis como biorremediadores de ambientes afetados por este herbicida.(AU)

Glyphosate is one of the most widely used herbicides. The World Health Organization (WHO) has reclassified glyphosate as "probably carcinogenic to humans". Glyphosate removal from the environment can be performed by microbial enzymatic action. The present work focused on the isolation of soil microorganisms that can tolerate glyphosate as the sole carbon source. Cells were isolated in minimal culture medium supplemented with glyphosate. Microbial biomass production was verified in the presence and absence of glyphosate. Seventeen, fourteen and one bacteria, fungi and yeast were isolated, respectively. One fungus (F3) and one yeast (L1), were selected after glyphosate tolerance test in liquid medium. Eukaryotic microorganisms tolerate glyphosate, however metabolism was affected by herbicide compared to control without glyphosate. Statistically growth time showed significant differences. Eukaryotic microorganisms isolated from soil with glyphosate are tolerant to the compound and may be useful as bioremediators of environments affected by this herbicide.(AU)

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White mold disease, caused by fungus Sclerotinia sclerotiorum (Lib.) de Bary., is a disease hard to control due to the high amount of sclerotia produced, which guarantees its survival in the soil for years leading to significant yield losses. Alternative techniques to control the pathogen have been researched, including homeopathy. The present work aimed to evaluate the in vitro antifungal effect of homeopathic medicines on S. sclerotiorum mycelial growth. Homeopathic medicines Sulphur, fungal sclerotium Nosode and Calcarea carbonica, in 30CH, 200CH and 1000CH dynamizations were tested. Assays were carried out in a completely randomized design, with four repetitions. Experiments were performed through the addition of homeopathic medicines on the surface of plates containing culture medium, followed by insertion of a disc containing fungus mycelia and incubation. Control treatment received no homeopathic medicine. The mycelial progression was monitored by seven halo diameter measurements during experiment period. All homeopathic medicines tested and their dynamizations were able to inhibit partially the development of the fungus. Calcarea carbonica at the dynamization of 1000 CH showed the best inhibitory effect on S. sclerotiorum, which under its effect produced a mycelial halo 40% smaller than the control treatment.

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White mold disease, caused by fungus Sclerotinia sclerotiorum (Lib.) de Bary., is a disease hard to control due to the high amount of sclerotia produced, which guarantees its survival in the soil for years leading to significant yield losses. Alternative techniques to control the pathogen have been researched, including homeopathy. The present work aimed to evaluate the in vitro antifungal effect of homeopathic medicines on S. sclerotiorum mycelial growth. Homeopathic medicines Sulphur, fungal sclerotium Nosode and Calcarea carbonica, in 30CH, 200CH and 1000CH dynamizations were tested. Assays were carried out in a completely randomized design, with four repetitions. Experiments were performed through the addition of homeopathic medicines on the surface of plates containing culture medium, followed by insertion of a disc containing fungus mycelia and incubation. Control treatment received no homeopathic medicine. The mycelial progression was monitored by seven halo diameter measurements during experiment period. All homeopathic medicines tested and their dynamizations were able to inhibit partially the development of the fungus. Calcarea carbonica at the dynamization of 1000 CH showed the best inhibitory effect on S. sclerotiorum, which under its effect produced a mycelial halo 40% smaller than the control treatment.(AU)

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In the last decades, efforts to reduce the use of fossil fuels have increased the search for alternative sustainable sources of renewable energy. In this scenario, hydrocarbons derived from fatty acids are among the compounds that have been drawing attention. The intracellular production of hydrocarbons by bacteria derived from cold environments such as the Antarctic continent is currently poorly investigated, as extremophilic microorganisms provide a great range of metabolic capabilities and may represent a key tool in the production of biofuels. The aim of this study was to explore the ability of bacterial cells derived from extreme environments to produce hydrocarbons with potential for further use as biofuels. Seven bacteria isolated from Antarctic samples were evaluated for hydrocarbon production using GC-MS approaches. Two isolates, identified as Arthrobacter livingstonensis 593 and Pseudoalteromonas arctica 628, were able to produce the hydrocarbon undecane (CH3-(CH2)9-CH3) in concentrations of 1.39 mg L-1 and 1.81 mg L-1, respectively. Results from the present work encourage further research focusing on the optimization of hydrocarbon production by the isolates identified as producers, which may be used in further aircraft biofuel production. This is the first report on the production of the undecane compound by bacteria isolated from waterlogged soil and sponge from Antarctica.

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