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The present work aimed to characterize and compare the catalytic properties of amylases from Cunninghamella echinulata and Rhizopus microsporus. The highest production of amylase by C. echinulata, 234.94 U g-1 of dry substrate (or 23.49 U mL-1), was obtained using wheat bran as a substrate, with 50-55% initial moisture and kept at 28 °C for 48 h. The highest production of amylases by R. microsporus, 224.85 U g-1 of dry substrate (or 22.48 U mL-1), was obtained cultivating wheat bran with 65% initial moisture at 45 °C for 24 h. The optimal activity of the amylases was observed at pH 5.0 at 60 °C for C. echinulata enzymes and at pH 4.5 at 65 °C for R. microsporus. The amylases produced by C. echinulata were stable at pH 4.0-8.0, while the R. microsporus enzymes were stable at pH 4.0-10.0. The amylases produced by C. echinulata remained stable for 1 h at 50 °C and the R. microsporus amylases maintained catalytic activity for 1 h at 55 °C. The enzymatic extracts of both fungi hydrolyzed starches from different plant sources and showed potential for liquefaction of starch, however the amylolytic complex of C. echinulata exhibited greater saccharifying potential.

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The use of fungi to obtain chitin and chitosan has advantages such as handling, extraction, and production control, thus allowing to generate high quality chitosan. This study aimed to isolate and identify strains of Cunninghamella spp., and assess the production of biomass, chitin, and chitosan. We determined the macroscopic and microscopic phenotypic aspects of the superiors, mycelial growth rate index, consumption of glucose and nitrogen, as well as the pH variation, and the production of biomass, chitin, and chitosan. After assessing the mycelial growth speed index, considered fast, we found that the UFT-Ce08 and UFT-Ce09 isolates showed a higher growth speed. Therefore, we assessed the sporulation of the isolates, and all of them reached the concentration of 106spores mL-1in the period of 96 hours. The YPD was considered ideal for biomass production because it promotes an efficient consumption and synthesis of organic compounds by microorganisms. The assessment of the biomass production and the chitin and chitosan yield of nine isolates and the reference strain showed that the UFT-Ce08 isolate had the highest amount of biomass, the UFT-Ce11 isolate had the highest chitin yield, and despite having the second smallest biomass, the UFT-Ce09 isolate had thehighest chitosan yield. Seven isolates showed higher chitosan yield than the reference strain. Therefore, chitosan production from this fungus can be further optimized to improve yield on a large-scale production. Chitosan production from this fungus can be further optimized to improve yield in large-scale production.(AU)

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Candida species are responsible for causing invasive candidiasis with high mortality rate and their resistance to available antifungal drugs is a major clinical challenge. Biotransformation process of the labdane diterpene ent-labd-8(17)-en-15,18-dioic acid (1) carried out with Cunninghamella elegans afforded five new derivatives (compounds 2-6). Unusual regioselective hydroxylation of the methyl group at the C-20 position of labdane-type diterpene was achieved and all compounds were subjected to cytotoxicity and antifungal evaluations. Compound 1 and its derivatives were not cytotoxic to normal (MCF-10A) and tumor (MCF-7) cell lines. Compounds 2 and 3 exhibited fungistatic activity against all tested Candida strains at lower concentrations than fluconazole. Both compounds also showed the strongest fungicidal activity against C. albicans, which is the most prevalent fungal agent involved in candidemia.

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AIMS: The objective of this study was to determine the best conditions to produce invertase by Cunninghamella echinulata PA3S12MM and to immobilize and apply the enzyme. METHODS AND RESULTS: The maximum production was verified in 8 days of cultivation at 28°C supplemented with 10 g L-1 apple peel, reaching 1054.85 U ml-1 . The invertase was purified from the DEAE-Sephadex column. The derivative immobilized in alginate-gelatin-calcium phosphate showed reusability >50% for 19 cycles. The derivative immobilized in glutaraldehyde-chitosan showed greater thermostability and at a different pH. The hydrolysis of 15 ml of sucrose 500 g L-1 in a fixed bed reactor (total volume of 31 ml) produced 24.44 µmol min-1 of glucose and fructose at a residence time of 30 min and a conversion factor of 0.5. CONCLUSIONS: The new wild strain C. echinulata PA3S12MM presents high invertase production in medium supplemented with an agro-industrial residue and the immobilized enzyme showed high thermal stability and resistance at a different pH. SIGNIFICANCE AND IMPACT OF THE STUDY: The fungus C. echinulata PA3S12MM is an excellent producer of invertases in Vogel medium supplemented with apple peel. The enzyme is promising for industrial application since it has good performance in reusability and inverted sugar production.

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The goal of the biotransformation process is to develop structural changes and generate new chemical compounds, which can occur naturally in mammalian and microbial organisms, such as filamentous fungi, and represent a tool to achieve enhanced bioactive compounds. Cunninghamella spp. is among the fungal models most widely used in biotransformation processes at phase I and II reactions, mimicking the metabolism of drugs and xenobiotics in mammals and generating new molecules based on substances of natural and synthetic origin. Therefore, the goal of this review is to highlight the studies involving the biotransformation of Cunninghamella species between January 2015 and March 2021, in addition to updating existing studies to identify the similarities between the human metabolite and Cunninghamella patterns of active compounds, with related advantages and challenges, and providing new tools for further studies in this scope.

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Pulmonary mucormycosis and aspergillosis with disseminated mucormycosis involving gastrointestinalin is a very rare but lethal infection leading to extreme mortality. Herein, we present a unique case of pulmonary coinfection with Cunninghamella bertholletiae and Aspergillus flavus, with disseminated mucormycosis involving the jejunum caused by C. bertholletiae in an acute B-lymphocytic leukemia (B-ALL) patient with familial diabetes. Early administration of active antifungal agents at optimal doses and complete resection of all infected tissues led to improved therapeutic outcomes.

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The Cunninghamella echinulata PA3S12MM fungus is a great producer of invertases in a growth medium supplemented by apple peels. The enzyme was purified 4.5 times after two chromatographic processes, and it presented a relative molecular mass of 89.2 kDa. The invertase reached maximum activity at pH of 6 and at 60°C, in addition to presenting stability in alkaline pH and thermal activation at 50°C. The enzymatic activity increased in the presence of Mn2+ and dithiothreitol (DTT), while Cu2+ and Z2+ ions inhibited it. Also, DTT showed to protect enzymatic activity. The apparent values for Km , Vmáx , and Kcat for the sucrose hydrolysis were, respectively, 173.8 mmol/L, 908.7 mmol/L min-1 , and 1,388.79 s-1 . The carbohydrate content was of 83.13%. The invertase presented hydrolytic activity over different types of glycosidic bonds, such as α1 â†” 2ß (sucrose), α1 â†’ 4 (polygalacturonic acid), α1 â†’ 4 and α1 â†’ 2 (pectin), and α1 â†” 1 (trehalose), indicating that the enzyme is multifunctional. Thus, the biochemical properties showed by the C. echinulata PA3S12MM suggest a broad industrial application, such as in the biomass hydrolysis or in the food industry. PRACTICAL APPLICATIONS: Invertases are hydrolytic enzymes employed in several industrial sectors. Given their great importance for the economy and several industrial sectors, there is a growing interest in microorganisms producing this enzyme. The analysis of the biochemical properties of invertase in C. echinulata PA3S12MM suggest applications in the food industry. Due to its increased hydrolytic activity, the hydrolysis process of the sucrose may employ invertase for the production of invert sugar. The stability at alkaline pH suggests an application in the development of enzymatic electrodes for the quantification of sucrose in food and beverage. The multifunctional activity may work in the biomass hydrolysis or saccharification of by-products for the extraction of fermentable sugars. The high level of invertase N-linked glycosylation of invertase grants this enzyme thermal stability at high temperatures, in addition to resistance against the action of proteases, which are desirable characteristics for the application of this enzyme in industrial processes.

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Animal chitosan (Chit-A) is gaining more acceptance in daily activities. It is used in a range of products from food supplements for weight loss to even raw materials for producing nanoparticles and hydrogel drug carriers; however, it has low antioxidant activity. Fungal oligochitosan (OChit-F) was identified as a potential substitute for Chit-A. Cunninghamella elegans is a fungus found in the Brazilian savanna (Caatinga) that produces OligoChit-F, which is a relatively poorly studied compound. In this study, 4 kDa OChit-F with a 76% deacetylation degree was extracted from C. elegans. OChit-F showed antioxidant activity similar to that of Chit-A in only one in vitro test (copper chelation) but exhibited higher activity than that of Chit-A in three other tests (reducing power, hydroxyl radical scavenging, and iron chelation). These results indicate that OChit-F is a better antioxidant than Chit-A. In addition, Chit-A significantly increased the formation of calcium oxalate crystals in vitro, particularly those of the monohydrate (COM) type; however, OChit-F had no effect on this process in vitro. In summary, OChit-F had higher antioxidant activity than Chit-A and did not induce the formation of CaOx crystals. Thus, OChit-F can be used as a Chit-A substitute in applications affected by oxidative stress.

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Os fungos desempenham vários papéis que impactam a humanidade de diversas maneiras. Suas características metabólicas são importantes na biotecnologia, porém, tais microrganismos podem desencadear alguns problemas de saúde pública e até mesmo serem letais. Objetivo: detectar a presença de fungos no acervo de uma biblioteca no município de São José do Rio Preto. Metodologia: foram coletadas quarenta amostras nas superfícies inanimadas (livros, estantes, documentos, mapas, artigos e revistas) das principais salas da biblioteca com o auxílio de swabs umedecidos em solução salina estéril, posteriormente encaminhados ao laboratório de Biomedicina da Universidade Paulista ­ UNIP. As amostras foram semeadas em meio de cultura ágar Sabouraud Dextrose (SDA), tendo adicionado cloranfenicol e incubadas a 30 °C. Foi realizada a colônia gigante em todas as cepas crescidas em SDA para a realização da técnica de microcultivo para a identificação dos fungos, de acordo com o Manual de Detecção e Identificação dos Fungos de Importância Médica da Agência Nacional de Vigilância Sanitária. Resultados: Houve positividade em trinta e uma amostras (78%) e em quatro delas foi observado mais de um tipo de colônia (13%). Das vinte e duas superfícies de livros analisadas, foram isolados e identificados: Aspergillus flavus, Aspergillus niger, Cunninghamella sp., Cladosporium sp., Curvularia sp., Mucor sp. e Nigrospora sp. Nas oito superfícies de estantes: Aspergillus flavus, Aspergillus niger, Aspergillus versicolor, Penicillium sp. e Scopulariopsis sp. e, nos dez documentos: Aspergillus nidulans, Aspergillus sp., Cladosporium sp., Cunninghamella sp. e Trichoderma sp. Conclusão: Os fungos encontrados estão amplamente distribuídos no ambiente como solo e ar e, por diversos fatores, instalam-se em locais como bibliotecas. Em condições favoráveis, podem infectar o homem e causar perdas patrimoniais para os acervos.

Fungi play many roles that impact humankind in different ways. Their metabolic characteristics are important in biotechnology; however, these microorganisms can trigger some public health problems or may even be lethal. Objective: detect the presence of fungi in the collection of a public library in the city of São José do Rio Preto, Brazil. Methods: a total of forty samples were collected from inanimate surfaces (books, shelves, documents, maps, articles and magazines) located in the main rooms of the library with swabs soaked in sterile saline solution and sent to the Universidade Paulista ­ UNIP laboratories. The samples were plated in Sabouraud Dextrose Agar (SDA) supplemented with chloramphenicol and incubated at 30 °C. The colonies that grew in SDA were isolated in Potato Dextrose Agar for performing the slide culture technique for the identification of the fungi, performed according to the Manual of Detection and Identification of Fungi of Medical Importance from the Brazilian Health Surveillance Agency (ANVISA). Results: Thirty-one samples (78%) were positive, and in four of them more than one fungus genus was observed (13%). From the twenty-two book surfaces analyzed, the following fungi were isolated and identified: Aspergillus flavus, Aspergillus niger, Cunninghamella sp., Cladosporium sp., Curvularia sp., Mucor sp. and Nigrospora sp. On the eight shelves: Aspergillus flavus, Aspergillus niger, Aspergillus versicolor, Penicillium sp. and Scopulariopsis sp. The ten documents analyzed presented the following fungi: Aspergillus nidulans, Aspergillus sp., Cladosporium sp., Cunninghamella sp. and Trichoderma sp.. Conclusion: These fungi are widely distributed in the environment such as in the soil and air, and due to several factors, they colonize public places, such as libraries. In favorable conditions, they may infect humans and cause diseases.

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BACKGROUND: The strategic development of therapeutic agents, capable of being targeted at their active sites, has been a major goal in treatment of cancer. The delivery of drugs for tumors has as its main challenge the development of safe and effective drugs, since the goal of chemotherapy is to eliminate the tumor completely without affecting healthy cells. The aim of present study was to investigate the antioxidant, anticancer activities of zidovudine and its α-O-glycosylated derivative obtained by biosynthesis of a filamentous fungi, Cunninghamela echinulata. METHODS: An evaluation of the cytotoxic potential of zidovudine and its α-O-glycosylated was performed in fibroblasts and melanoma cells by the tetrazolium reduction method (MTT) and the antioxidant activity of this derivative was observed. RESULTS: The antioxidant activity of zidovudine demonstrated an electrochemical oxidation potential of 0.91V, while the α-O-glycosylated derivative did not exhibit any antioxidant activity. The zidovudine exhibited low cytotoxicity for melanoma and fibroblast cells, while the α-O-glycosylated derivative presented better cytotoxicity on melanoma cells at a concentration of 10mg. mL-1. CONCLUSION: This study demonstrates the specific cytotoxicity of the glycoconjugate and suggests that glycosylation by biosynthesis can be a useful strategy for obtaining new anticancer compounds.

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