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1.
Braz. arch. biol. technol ; 63: e20180673, 2020. tab
Article in English | LILACS | ID: biblio-1132156

ABSTRACT

Abstract Endophytic fungi belonging to the genus Muscodor now transferred to Induratia are known producers of bioactive volatile organic compounds (VOCs) with many industrial applications. However, the members of this genus have rarely been reported to produce non-volatile metabolites including enzyme. Enzymes of the endophytes are degraders of the polysaccharides available in the host plants and the knowledge of enzyme production by Induratia spp. may provide insights into their possible biotechnological applications. The aim of this study was to evaluate the activity of amylase, cellulase, lipase, pectinase, phytase, protease, endo β-1,4 glucanase and exo β-1,4 glucanase enzymes produced by fungi of the species Induratia coffeana, Induratia yucatanensis and Induratia sp. isolated from organic coffee plants. All Induratia spp. were able to produce the extracellular enzymes cellulase, pectinase, protease, and phytase. Eight fungi were able to produce lipase and four produced amylase. The specific activity of endo β-1, 4 glucanase and exo β-1,4 glucanase enzymes were detected for 9 and 8 endophytic fungi, respectively. This work demonstrated for the first time, the array of enzymes produced by Induratia spp. isolated from Coffea arabica in organic systems in Brazil.


Subject(s)
Coffea/microbiology , Enzyme Activation , Volatile Organic Compounds/metabolism , Endophytes/enzymology , Brazil
2.
Rev. argent. microbiol ; 49(2): 189-196, jun. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-957998

ABSTRACT

El paraquat es un herbicida utilizado ampliamente en la agricultura. Debido a su gran distribución y uso inadecuado, representa un problema grave de contaminación del suelo y el agua. Se ha encontrado que los hongos de la podredumbre blanca son capaces de degradar compuestos contaminantes que poseen estructuras similares a la lignina, como es el caso del paraquat. En el presente trabajo se evaluó la degradación de este herbicida y su efecto en la producción de enzimas ligninolíticas por parte de algunos hongos de la podredumbre blanca aislados del sur de México. Seis cepas fúngicas mostraron tolerancia al herbicida durante el cultivo en medio sólido. Tres de las 6 cepas evaluadas, correspondientes a las especies Polyporus tricholoma, Cilindrobasidium laeve y Deconica citrispora, mostraron niveles de degradación del 32, el 26 y el 47%, en ese orden, a los 12 días de cultivo en presencia del xenobiótico. Se detectó un incremento en las actividades de las enzimas lacasa y Mn-peroxidasa en las cepas que presentaron el mayor porcentaje de degradación, probablemente asociado a la disminución del herbicida. Adicionalmente, se realizaron ensayos con extractos enzimáticos procedentes del medio de cultivo extracelular de las 2 cepas que presentaron mayor degradación. Después de 24 h de incubación, se obtuvo una degradación del 49% del paraquat inicial con los extractos de D. citrispora. Los resultados obtenidos indican que la degradación del herbicida estaría asociada a la presencia de enzimas extracelulares en los hongos de la podredumbre blanca. En este trabajo se muestran las primeras evidencias del potencial de biodegradación de diferentes especies de hongos de la pudrición blanca.


Paraquat is a widely used herbicide in agriculture. Its inappropriate use and wide distribution represents a serious pollution problem for soil and water. White rot fungi are capable of degrading pollutants having a similar structure to that of lignin, such as paraquat. This study evaluated the degradation effect of paraquat on the production of ligninolytic enzymes by white rot fungi isolated from the South of Mexico. Six fungal strains showed tolerance to the herbicide in solid culture. Three of the six evaluated strains showed levels of degradation of 32, 26 and 47% (Polyporus tricholoma, Cilindrobasidium laeve and Deconica citrispora, respectively) after twelve days of cultivation in the presence of the xenobiotic. An increase in laccase and manganese peroxidase (MnP) activities was detected in the strains showing the highest percentage of degradation. Experiments were done with enzyme extracts from the extracellular medium with the two strains showing more degradation potential and enzyme production. After 24 hours of incubation, a degradation of 49% of the initial paraquat concentration was observed for D. citrispora. These results suggest that paraquat degradation can be attributed to the presence of extracellular enzymes from white rot fungi. In this work the first evidence of the biodegradation potential of D. citrispora and Cilindrobasidium leave is shown.


Subject(s)
Paraquat , Peroxidases , Fungi , Herbicides , Paraquat/metabolism , Biodegradation, Environmental , Laccase , Fungi/enzymology , Herbicides/metabolism , Lignin , Mexico
3.
Rev. odontol. UNESP (Online) ; 45(4): 219-226, July-Aug. 2016. tab, ilus
Article in Portuguese | LILACS, BBO | ID: lil-795230

ABSTRACT

Introdução: A habilidade da Candida spp. em produzir enzimas proteolíticas, tais como fosfolipase e proteinases, tem um papel importante na patogenicidade destas leveduras. Objetivo: Determinar as espécies causadoras das infecções orais por Candida spp., além de investigar a atividade in vitro das fosfolipases e proteinases em isolados clínicos do gênero Candida, provenientes de pacientes com candidíase oral. Material e método: Isolados de Candida spp., pertencentes à Coleção de Cultivos Fúngicos do Laboratório de Microbiologia e Patologia Oral do Departamento de Odontologia da Faculdade da Serra Gaúcha, foram analisados. Produção de fosfolipases foi analisada utilizando-se Ágar gema de ovo. Liberação de proteinases foi medida utilizando-se extrato de levedura adicionado à albumina bovina. Resultado: Um total de 35 isolados clínicos do gênero Candida foi testado. C. albicans foi a espécie predominante (77%). Os demais isolados identificados foram: C. parapsilosis (20%) e C. tropicalis (2%). Ao comparar a atividade de fosfolipase do grupo C. albicans com o grupo Candida não-albicans, foi encontrada diferença significativa (P=0,04). Não foi encontrada diferença significativa entre a C. albicans e a C. não-albicans, para a produção de proteinase. A liberação de proteinase foi significativamente maior quando comparada à produção de fosfolipase para o gênero Candida (P=0,04). Diferença estatisticamente significativa foi encontrada quando a atividade de fosfolipase e proteinase da C. albicans foi comparada à atividade das espécies de C. não-albicans (P=0,02). Conclusão: Diferentes quantificações de fosfolipase extracelular e atividade de proteinase têm sido atribuídas aos isolados clínicos de C. albicans quando comparados a outras espécies de Candida.


Introduction: The ability of the genus Candida to produce secretory enzimes such as proteinase and phospholipases to play an important role in the patogenicity of these yeasts. Objective: To determine the Candida species isolates from oral cavity infections and to investigate in vitro phospholipase and protease activities in clinically important of the genus Candida isolated in oral candidiasis patients. Material and method: Candida species isolated of the Fungal Culture Collection of Oral Microbiology and Pathology Testing Service Laboratory of the Dentistry Departament of Faculdade da Serra Gaúcha were evaluated. The phospholipases detection was assayed using the egg yolk agar plate method. Determination of protease production was performed in agar plates containing bovine serum albumine and yeasts extract. Result: A total of 35 isolates of the genus Candida were tested. C. albicans was the species predominant (77% of isolates), followed by C. parapsilosis (20%) and C. tropicalis (2%). When compared the phospholipase activity of the C. albicans group with the non-albicans Candida species types group was observed significant difference among of this groups (P=0.04). No statiscally significant difference between the C.albicans and non-albicans Candida species types when was compared to proteinase production. Proteinase production was higher and statiscally significant when compared to phospholipase activity in the genus Candida isolates (P=0.04). Statiscally significant differences were found between phosphoplipases and proteases activity for C. albicans when compared to non-albicans Candida species types (P=0.02). Conclusion: Differences in the secretion rates of phospholipase extracellular and proteases activity have been attributed to clinical strains of C. albicans when compared to others Candida species types.


Subject(s)
Peptide Hydrolases , Phospholipases , In Vitro Techniques , Candida , Candida albicans , Candidiasis, Oral , Serum Albumin, Bovine , Virulence Factors , Enzymes , Yeasts , Infections , Mouth
4.
Braz. arch. biol. technol ; 57(3): 421-426, May-June 2014. graf, tab
Article in English | LILACS | ID: lil-709393

ABSTRACT

The aim of this work was to study the production of extracellular α-amylase by Kluyveromyces marxianus IF0 0288 using optimized nutritional and cultural conditions in a complex yeast medium under aerobic batch fermentation. By applying the conventional "one-variable-at-a-time" approach and the response surface methodology, the effect of four fermentation parameters (type of carbon source, initial culture pH, temperature, and incubation time) on the growth and α-amylase production was evaluated. The production of α-amylase during 60 h of fermentation increased 13-fold under optimized conditions (1% starch, pH 6.0, 30ºC) in comparison to the conventional optimization method. The initial pH value of 6.13 and temperature of 30.3ºC were optimal conditions by the response surface methodology, leading to further improvement (up to 13-fold) in the production of extracellular α-amylase. These results constituted first evidence that K. marxianus could be potentially used as an effective source of extracellular α-amylase.

5.
Indian J Ophthalmol ; 2014 Feb ; 62 (2): 196-203
Article in English | IMSEAR | ID: sea-155534

ABSTRACT

Purpose: This work was conducted to study the ability of bacterial and fungal isolates from keratitis cases in Upper Egypt to produce enzymes, toxins, and to test the isolated fungal species sensitivity to some therapeutic agents. Materials and Methods: One hundred and fifteen patients clinically diagnosed to have microbial keratitis were investigated. From these cases, 37 bacterial isolates and 25 fungal isolates were screened for their ability to produce extra‑cellular enzymes in solid media. In addition, the ability of fungal isolates to produce mycotoxins and their sensitivity to 4 antifungal agents were tested. Results: Protease, lipase, hemolysins, urease, phosphatase, and catalase were detected respectively in 48.65%, 37.84%, 59.46%, 43.24%, 67.57%, and 100% out of 37 bacterial isolates tested. Out of 25 fungal isolates tested during the present study, 80% were positive for protease, 84% for lipase and urease, 28% for blood hemolysis, and 100% for phosphatase and catalase enzymes. Thirteen fungal isolates were able to produce detectable amounts of 7 mycotoxins in culture medium (aflatoxins (B1, B2, G1, and G2), sterigmatocystin, fumagillin, diacetoxyscirpenol, zearalenone, T‑2 toxin, and trichodermin). Among the antifungal agents tested in this study, terbinafine showed the highest effect against most isolates in vitro. Conclusion: In conclusion, the ability of bacterial and fungal isolates to produce extracellular enzymes and toxins may be aid in the invasion and destruction of eye tissues, which, in turn, lead to vision loss.

6.
Article in English | IMSEAR | ID: sea-167160

ABSTRACT

During the course of survey of halophilic microorganisms, a total of sixteen bacterial isolates were obtained from coastal solar salterns of Orissa and West Bengal, India. Morphological, physiological and biochemical characteristics of these isolates indicate that majority of them belong to the genus Halomonas, however, members belonging to Cobetia and Halococcus were not uncommon. These isolates were screened for the production of extracellular enzymes such as amylase, glutaminase, asparaginase, xylanase, cellulase, gelatinase, inulinase, caseinase, pectinase, urease and lipase. Among these hydrolytic enzymes, glutamine and asparagine hydrolytic activities were predominant, although lipid and casein degrading activities were not inferior. However, amylase and gelatinase production were rare. None of these halophiles was able to degrade cellulose, inulin, pectin and xylan and only one isolate was capable of hydrolyzing urea.

7.
Braz. j. microbiol ; 43(2): 827-833, Apr.-June 2012. graf, tab
Article in English | LILACS | ID: lil-644502

ABSTRACT

Entomopathogenic fungi are important controllers of pest-insects populations in agricultural production systems and in natural environment. These fungi have enzymatic machinery which involve since the recognition and adherence of spores in their hosts culminating with infection and death of these insects. The main objective of this study was to analyzed extracellular enzyme production of the fungi strains Beauveria bassiana, Metarhizium anisopliae and Paecilomyces sp when cultured on substrates. These fungi were grown in minimal media containing specific substrates for the analysis of different enzymes such as amylases, cellulases, esterases, lipases, proteases (gelatin and caseinase), pectinases and cuticles of Musca domestica larvae and adults. All the assays were performed with and without the presence of dextrose in the culture media. The quantification of enzyme activity was performed by the ratio of halo / colony (H/C) and the results subjected to variance analysis level of 5% (ANOVA) followed by post-Tukey test. All strains were positive for lipase and also they showed a high significant enzyme production for gelatin at concentrations of 4 and 1%. B. bassiana and Paecilomyces sp. were positive for amylase, pectinase and caseinase, and only Paecilomyces sp. showed cellulase activity.


Subject(s)
Agricultural Pests , Beauveria/genetics , Entomology , Hydrolases/analysis , Insecta , Mitosporic Fungi , Metarhizium/enzymology , Metarhizium/pathogenicity , Paecilomyces/enzymology , Spores, Fungal , Enzyme Activation , Methods , Virulence
8.
Braz. j. microbiol ; 42(3): 937-947, July-Sept. 2011. tab
Article in English | LILACS | ID: lil-607522

ABSTRACT

The diversity of yeasts collected from different sites in Antarctica (Admiralty Bay, King George Island and Port Foster Bay and Deception Island) and their ability to produce extracellular enzymes and mycosporines were studied. Samples were collected during the austral summer season, between November 2006 and January 2007, from the rhizosphere of Deschampsia antarctica, ornithogenic (penguin guano) soil, soil, marine and lake sediments, marine water and freshwater from lakes. A total of 89 isolates belonging to the following genera were recovered: Bensingtonia, Candida, Cryptococcus, Debaryomyces, Dioszegia, Exophiala, Filobasidium, Issatchenkia (Pichia), Kodamaea, Leucosporidium, Leucosporidiella, Metschnikowia, Nadsonia, Pichia, Rhodotorula, and Sporidiobolus, and the yeast-like fungi Aureobasidium, Leuconeurospora and Microglossum. Cryptococcus victoriae was the most frequently identified species. Several species isolated in our study have been previously reported to be Antarctic psychophilic yeasts, including Cr. antarcticus, Cr. victoriae, Dioszegia hungarica and Leucosporidium scottii. The cosmopolitan yeast species A. pullulans, C. zeylanoides, D. hansenii, I. orientalis, K. ohmeri, P. guilliermondii, Rh. mucilaginosa, and S. salmonicolor were also isolated. Five possible new species were identified. Sixty percent of the yeasts had at least one detectable extracellular enzymatic activity. Cryptococcus antarcticus, D. aurantiaca, D. crocea, D. hungarica, Dioszegia sp., E. xenobiotica, Rh. glaciales, Rh. laryngis, Microglossum sp. 1 and Microglossum sp. 2 produced mycosporines. Of the yeast isolates, 41.7 percent produced pigments and/or mycosporines and could be considered adapted to survive in Antarctica. Most of the yeasts had extracellular enzymatic activities at 4ºC and 20ºC, indicating that they could be metabolically active in the sampled substrates.


Subject(s)
Biodiversity , Environmental Microbiology , Enzyme Activation , Enzymes/analysis , Yeasts/isolation & purification , Yeasts/metabolism , Rhizophoraceae/genetics , Rhizophoraceae/metabolism , Seawater , Methods , Methods
9.
Mycobiology ; : 118-120, 2011.
Article in English | WPRIM | ID: wpr-729399

ABSTRACT

The ability of Ganoderma to produce extracellular enzymes, including beta-glucosidase, cellulase, avicelase, pectinase, xylanase, protease, amylase, and ligninase was tested in chromogenic media. beta-glucosidase showed the highest activity, among the eight tested enzymes. In particular, Ganoderma neo-japonicum showed significantly stronger activity for beta-glucosidase than that of the other enzymes. Two Ganoderma lucidum isolates showed moderate activity for avicelase; however, Ganoderma neo-japonicum showed the strongest activity. Moderate ligninase activity was only observed in Ganoderma neo-japonicum. In contrast, pectinase, amylase, protease, and cellulase were not present in Ganoderma. The results show that the degree of activity of the tested enzymes varied depending on the Ganoderma species tested.


Subject(s)
Amylases , beta-Glucosidase , Cellulase , Cellulases , Ganoderma , Oxygenases , Polygalacturonase , Reishi
10.
Braz. arch. biol. technol ; 53(4): 779-783, July-Aug. 2010. graf
Article in English | LILACS | ID: lil-554770

ABSTRACT

Fusarium graminearum isolates from three different agroecological regions in Argentina were examined according to the production of different extracellular enzyme activities of potential biotechnological interest: pectinases (PGase: polygalacturonase and PMGase: polymethylgalacturonase), cellulase (CMCase: carboxymethylcellulase) and hemicellulase (xylanase). The isolates were grown in minimum salt medium supplemented with 0.25 percent glucose, 0.125 percent citric pectin and 0.125 percent oat bran as carbon sources and/or enzyme inducers. PGase activity was detected early (after two days of incubation) in all the cultures; it was found to be the highest for all the isolates. PMGase was high only for those isolates of the II region. CMCase and endoxylanase activities were particularly found at late stages (after four and seven days of incubation, respectively) and the maximum values were lower than pectinase activities.

11.
Mycobiology ; : 238-248, 2010.
Article in English | WPRIM | ID: wpr-729917

ABSTRACT

This review provides background information on the importance of bioremediation approaches. It describes the roles of fungi, specifically white rot fungi, and their extracellular enzymes, laccases, ligninases, and peroxidises, in the degradation of xenobiotic compounds such as single and mixtures of pesticides. We discuss the importance of abiotic factors such as water potential, temperature, and pH stress when considering an environmental screening approach, and examples are provided of the differential effect of white rot fungi on the degradation of single and mixtures of pesticides using fungi such as Trametes versicolor and Phanerochaete chrysosporium. We also explore the formulation and delivery of fungal bioremedial inoculants to terrestrial ecosystems as well as the use of spent mushroom compost as an approach. Future areas for research and potential exploitation of new techniques are also considered.


Subject(s)
Humans , Agaricales , Biodegradation, Environmental , Ecosystem , Fungi , Hydrogen-Ion Concentration , Mass Screening , Pesticides , Phanerochaete , Soil , Trametes , Water , Xenobiotics
12.
Mycobiology ; : 162-165, 2007.
Article in English | WPRIM | ID: wpr-729950

ABSTRACT

Thirty seven species of Fusarium were evaluated for their ability of producing extracellular enzymes using chromogenic medium containing substrates such as starch, cellobiose, CM-cellulose, xylan, and pectin. Among the tested species Fusarium mesoamericanum, F. graminearum, F. asiaticum, and F. acuminatum showed high beta-glucosidase acitivity. Xylanase activity was strongly detected in F. proliferatum and F. oxysporum. Strong pectinase activity was also found in F. oxysporum and F. proliferatum. Amylase activity was apparent in F. oxysporum. No clear activity in cellulase was found from all the Fusarium species tested.


Subject(s)
Amylases , beta-Glucosidase , Cellobiose , Cellulase , Fusarium , Polygalacturonase , Starch
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