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1.
Arch. latinoam. nutr ; 72(1): 50-59, mar. 2022. ilus, tab
Article in English | LILACS, LIVECS | ID: biblio-1368371

ABSTRACT

Crohn's disease (CD) is an inflammatory condition that can affect the entire gastrointestinal tract due to an exacerbated and inadequate immune system response. Objective. This study aimed to conduct a systematic review, through clinical trials, about the use of probiotics in humans with CD. Materials and methods. Research was carried out in the PubMed, Scopus and Science Direct databases using the keywords "Crohn's disease" and "probiotics". We conducted the review by searching clinical trials published from 2000 to December 2019. Results. Of 2,164 articles found, only nine were considered eligible for this review. The studies investigated patients with CD at different stages of the pathology, and in three studies the potential effect of probiotics in the active phase was observed; in two, in the remission phase; and in four, after intestinal surgery. The sample size of the studies ranged from 11 to 165 individuals and the age of the participants between 5 and 71 years. Gram-positive bacteria were used in six clinical interventions and in two studies yeasts were used. As for the significant results obtained with the treatment with probiotics, in one study there was beneficial clinical effects in patients and, in another, there was an improvement in intestinal permeability. Conclusion. Currently, it is not possible to establish a recommendation for probiotic therapy to control CD due to the few clinical trials with significant results. There is a need for more research on clinical intervention with probiotics in CD to clarify the action, define doses and time of use(AU)


La enfermedad de Crohn (EC) es una afección inflamatoria que puede afectar todo el tracto gastrointestinal debido a una respuesta del sistema inmunitario exacerbada e inadecuada. Objetivo. Realizar una revisión sistemática, a través de ensayos clínicos, sobre el uso de probióticos en humanos con EC. Materiales y métodos. La investigación se realizó en las bases de datos PubMed, Scopus y Science Direct utilizando las palabras clave "enfermedad de Crohn" y "probióticos". La revisión se hizo en ensayos clínicos publicados desde 2000 hasta diciembre 2019. Resultados. De 2164 artículos encontrados, solo nueve fueron considerados elegibles. Los estudios investigaron pacientes con EC en diferentes etapas de la patología, y en tres estudios se observó el efecto potencial de los probióticos en la fase activa; en dos, en remisión; y en cuatro, tras cirugía intestinal. El tamaño de la muestra fue entre 11 y 165 individuos y la edad entre 5 y 71 años. Se utilizaron bacterias grampositivas en seis intervenciones clínicas y en dos estudios se utilizaron levaduras. En cuanto a los resultados significativos obtenidos con el tratamiento con probióticos, en un estudio hubo efectos clínicos beneficiosos en los pacientes y, en otro, hubo una mejora en la permeabilidad intestinal. Conclusión. Actualmente, no es posible establecer una recomendación de terapia con probióticos para el control de la EC debido a los pocos ensayos clínicos con resultados significativos. Existe la necesidad de más investigación sobre la intervención clínica con probióticos en EC para aclarar la acción, definir dosis y tiempo de uso(AU)


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Crohn Disease , Probiotics , Gastrointestinal Tract , Gram-Positive Bacteria , Permeability , Yeasts , Inflammatory Bowel Diseases , PubMed , Immune System
2.
Article in Spanish | LILACS, CUMED | ID: biblio-1341785

ABSTRACT

La levadura metilotrófica Pichia pastoris (clasificada actualmente como Komagataella phaffii) es una de las más importantes para la producción de proteínas heterólogas. En el trabajo se presenta un análisis de las principales características que se ponen de manifiesto en la expresión de proteínas recombinantes expresadas en este microorganismo. Se describen las cepas disponibles para la transformación y producción de proteínas recombinantes expresadas en Pichia pastoris, los principales vectores comerciales para la expresión, los promotores más eficientes, los marcadores seleccionables, la señal de secreción, los métodos usados en las transformaciones genéticas y los patrones de glicosilación que se presentan. Se brindan recomendaciones generales acerca de los parámetros de bioprocesos como la composición del medio, el pH, la temperatura, la velocidad de aireación, la inducción y las estrategias de alimentación para alcanzar altos valores de productividad. Se presentan los resultados de las aplicaciones de Pichia pastoris en la producción de dos vacunas en Cuba, la vacuna contra la hepatitis B y la vacuna para el control de la garrapata(AU)


Pichia pastoris metylotrofic yeast (currently classified as Komagataella phaffii) is one of the most important yeast for the production of heterologous proteins. The work presents an analysis of the main characteristics that are marked in the production of recombinant proteins expressed in Pichia pastoris. It describes the strains available for the transformation and production of recombinant proteins expressed in P. pastoris, the main commercial vectors for expression, the most efficient promoters, selectable markers, the secretion signal, the methods used in genetic transformations and glycosylation patterns that occur. General recommendations are provided on bioprocess parameters such as media composition, pH, temperature, aeration velocity, induction, and feeding strategies to achieve high productivity values. The results of Pichia pastoris applications for the production of two vaccines in Cuba, the hepatitis B vaccine and the tick control vaccine are shown(AU)


Subject(s)
Pichia , Yeasts , Recombinant Proteins , Protein Engineering , Tick Control/methods , Hepatitis B Vaccines/therapeutic use , Cuba
3.
Rev. Ciênc. Méd. Biol. (Impr.) ; 20(2): 245-252, set 29, 2021. tab
Article in English | LILACS | ID: biblio-1354441

ABSTRACT

Introducción: Cryptococcus neoformans es una levadura encapsulada, que se encuentra en fuentes ambientales, incluyendo excrementos de palomas. Tiene una gran relevancia clínica porque es el agente etiológico de la criptococosis, considerada una causa importante de mortalidad en personas inmunocomprometidas en todo el mundo. Objetivo: determinar la prevalencia y susceptibilidad de C. neoformans aislados del suelo y excremento de palomas en la ciudad de Maceió ­ Alagoas, Brasil. Metodología: Se recolectaron 150 muestras (50 de excretas secas, 50 de excretas frescas y 50 del suelo) y cultivaron en Agar Dextrosa Sabouraud. Las colonias aisladas sugestivas de C. neoformans se sometieron a identificación y caracterización mediante análisis morfológicos, actividad de la enzima fenol-oxidasa, sensibilidad a la cicloheximida, desarrollo a 37°C, hidrólisis de urea, asimilación de carbono y nitrógeno y fenotipificación en medio canavanina-glicina-azul de bromotimol. La prueba de susceptibilidad antifúngica se realizó utilizando la técnica de difusión en agar. Resultados: se obtuvieron 36 (24%) muestras positivas para C. neoformans, de las cuales 33 fueron de excretas secas y 3 del suelo cercano al excremento. El perfil de susceptibilidad fue de 100.0% para anfotericina B y 87.4% para ketoconazol, no obstante, hubo un alto porcentaje de resistencia a fluconazol (91.5%) e itraconazol (80.0%). Conclusión: estos hallazgos confirman que las excretas de palomas secas son reservorios de C. neoformans en el medio ambiente, caracterizando un problema de salud única. Además, la anfotericina B exhibió una alta actividad in vitro, representando buena alternativa en el tratamiento de la criptococosis.


Introdução: Cryptococcus neoformans é um fungo leveduriforme encapsulado, encontrado em fontes ambientais, incluindo excretas de pombos. Apresenta grande relevância clínica por ser agente etiológico da criptococose, considerada importante causa de mortalidade em indivíduos imunocomprometidos em todo o mundo. Objetivo: determinar a prevalência e suscetibilidade de C. neoformans isolados do solo e de excretas de pombos na cidade de Maceió, Alagoas. Metodologia: foram coletadas 150 amostras (50 de excretas secas, 50 de excretas frescas e 50 do solo) e cultivadas em Ágar Sabouraud Dextrose. As colônias isoladas sugestivas de C. neoformans foram submetidas à identificação e caracterização por meio de análises morfológicas, atividade da enzima fenoloxidase, sensibilidade à cicloheximida, termotolerância à 37ºC, hidrólise da ureia, assimilação de carbono e nitrogênio e quimiotipagem em ágar L-canavanina-glicina-azul de bromotimol. O teste de suscetibilidade antifúngica foi realizado por meio da técnica de difusão em ágar. Resultados: foram obtidas 36 (24%) amostras positivas para C. neoformans, das quais 33 (91,6%) foram provenientes de excretas secas e 3 (8,3%) do solo próximo a excrementos. O perfil de suscetibilidade foi de 100,0% para a anfotericina B e 87,4% para o cetoconazol, não obstante, verificou-se alto percentual de resistência ao fluconazol (91,8%) e itraconazol (80%). Conclusão: estes achados confirmam que excretas de pombos secas são reservatórios de C. neoformans no ambiente, caracterizando um problema de saúde única. Além disso, a anfotericina B apresentou elevada atividade, in vitro, representando boa alternativa no tratamento da criptococose.


Subject(s)
Animals , Male , Female , Columbidae , Yeasts , Cryptococcosis , Cryptococcus neoformans
4.
Infectio ; 25(2): 130-134, abr.-jun. 2021. graf
Article in Spanish | LILACS, COLNAL | ID: biblio-1250079

ABSTRACT

Resumen El género Malassezia comprende levaduras lipofílicas, comensales de la piel de humanos y animales, responsables de infecciones dermatológicas y sistémicas, particularmente en recién nacidos pretérmino hospitalizados en Unidades de Cuidados Intensivos Neonatal (UCIN) con catéteres venosos centrales, antibióticos de amplio espectro y nutrición parenteral rica en lípidos. La información acerca de las fungemias por este microorganismo es limitada, sin embargo, la mayoría de infecciones invasivas reportadas en la literatura han sido asociadas con M. furfur y M. pachydermatis. Se reporta un caso de fungemia por M. sympodialis en un recién nacido pretérmino hospitalizado en la UCIN de un hospital colombiano con sospecha clínica de sepsis neonatal, antibioticoterapia de amplio espectro y hemocultivos de rutina negativos. El aislamiento fue susceptible a fluconazol y voriconazol, y resistente a anfotericina B. Existen pocos reportes de fungemia producida por M. sympodialis, pero todos concuerdan en que es una levadura subestimada en individuos con factores predisponentes.


Abstract The genus Malassezia comprises lipophilic yeasts, commensals of the skin of humans and animals, responsible for dermatological and systemic infections, particu larly in preterm infants hospitalized in Neonatal Intensive Care Units (NICU) with central venous catheters, broad-spectrum antibiotics and parenteral nutrition rich in lipids. Information about fungemia by this microorganism is limited, however, the majority of invasive infections reported in the literature have been associated with M. furfur and M. pachydermatis. A case of M. sympodialis fungemia is reported in a preterm newborn hospitalized in the NICU of a Colombian hospital with clinical suspicion of neonatal sepsis, broad-spectrum antibiotic therapy and negative routine blood cultures. The isolation was susceptible to fluconazole and voriconazole, and resistant to amphotericin B. There are few reports of fungemia produced by M. sympodialis, but all agree that it is an underestimated yeast in individuals with predisposing factors.


Subject(s)
Humans , Male , Infant, Newborn , Intensive Care Units, Neonatal , Fungemia , Malassezia , Skin , Yeasts , Colombia , Neonatal Sepsis , Infections
5.
Chinese Journal of Biotechnology ; (12): 2753-2764, 2021.
Article in Chinese | WPRIM | ID: wpr-887838

ABSTRACT

Biodiesel is an alternative fuel to addressing the energy shortage problem. Microbial lipids have attracted widespread attention as one of the potential feed-stocks for cost-effective and efficient biodiesel production. However, the large-scale production of microbial lipids is hampered by the complexity and the high cost of aseptic culturing approach. Metschnikowia pulcherrima is an oleaginous yeast with strong environmental adaptability. It is capable of utilizing a wide spectrum of substrates, and can be cultured under non-sterile conditions. Therefore, this yeast has great potential to replace the traditional oleaginous microorganisms, particularly in the area of recycling wastewater and solid waste for the production of biodiesel. Based on the analysis of lipid production and application conditions of M. pulcherrima, this review summarized the unique advantages of M. pulcherrima and the key factors affecting lipids production. We further discussed the feasibility of cultivating M. pulcherrima on various organic wastes under non-sterile conditions for lipids production. Moreover, we analyzed the challenges associated with M. pulcherrima's in the yield and mechanism for lipids production, and proposed perspectives for how to achieve efficient biodiesel production using this yeast.


Subject(s)
Biofuels , Candida , Lipids , Metschnikowia , Yeasts
6.
Chinese Journal of Biotechnology ; (12): 1659-1676, 2021.
Article in Chinese | WPRIM | ID: wpr-878660

ABSTRACT

Over the past 30 years, Yarrowia lipolytica, Kluyveromyces, Pichia, Candida, Hansenula and other non-conventional yeasts have attracted wide attention because of their desirable phenotypes, such as rapid growth, capability of utilizing multiple substrates, and stress tolerance. A variety of synthetic biology tools are being developed for exploitation of their unique phenotypes, making them potential cell factories for the production of recombinant proteins and renewable bio-based chemicals. This review summarizes the gene editing tools and the metabolic engineering strategies recently developed for non-conventional yeasts. Moreover, the challenges and future perspectives for developing non-conventional yeasts into efficient cell factories for the production of useful products through metabolic engineering are discussed.


Subject(s)
Gene Editing , Metabolic Engineering , Pichia/genetics , Synthetic Biology , Yarrowia/genetics , Yeasts
7.
Chinese Journal of Biotechnology ; (12): 966-979, 2021.
Article in Chinese | WPRIM | ID: wpr-878607

ABSTRACT

Methylotrophic yeasts are considered as promising cell factories for bio-manufacturing due to their several advantages such as tolerance to low pH and high temperature. In particular, their methanol utilization ability may help to establish a methanol biotransformation process, which will expand the substrate resource for bio-refinery and the product portfolio from methanol. This review summarize current progress on engineering methylotrophic yeasts for production of proteins and chemicals, and compare the strengths and weaknesses with the model yeast Saccharomyces cerevisiae. The challenges and possible solutions in metabolic engineering of methylotrophic yeasts are also discussed. With the developing efficient genetic tools and systems biology, the methylotrophic yeasts should play more important roles in future green bio-manufacturing.


Subject(s)
Metabolic Engineering , Methanol , Saccharomyces cerevisiae/genetics , Yeasts
8.
Rev. epidemiol. controle infecç ; 10(3): 1-16, jul.-set. 2020. ilus
Article in English | LILACS | ID: biblio-1247638

ABSTRACT

Justificativa e Objetivos: A candidíase oral tem uma ocorrência comum em pacientes imunocomprometidos. No entanto, outras infecções emergentes tornaram-se cada vez mais habituais. O objetivo deste estudo foi investigar a prevalência, os determinantes de virulência e a suscetibilidade a antifúngicos de leveduras que colonizam a mucosa de pacientes imunocomprometidos na região Nordeste do Brasil. Métodos: A amostra foi composta por 60 pacientes HIV positivos atendidos no Serviço de Atendimento Especializado/Hospital Dia do Hospital Universitário Prof. Alberto Antunes, vinculado à Universidade Federal de Alagoas. As amostras foram coletadas em regiões subgengivais e semeadas em CHROMagar para confirmação presuntiva de Candida spp., seguido por PCR e sequenciamento. Além disso, testamos os determinantes de virulência fosfolipase e protease e avaliamos in vitro a concentração inibitória mínima dos antifúngicos anfotericina B e fluconazol. Este projeto foi aprovado pelo Comitê de ética em pesquisa do Centro de Estudos Superiores de Maceió. Resultados: Aproximadamente 63% dos pacientes foram colonizados por leveduras. A espécie C. albicans foi predominante, enquanto as espécies de Candida não-albicans representaram 49% dos isolados, sendo C. dubliniensis e C. parapsilosis as mais comuns. Entretanto, C. intermedia, Bullera penniseticola e Naganishia liquefaciens também foram encontrados. Os determinantes da virulência protease e/ou fosfolipase também foram produzidos por Candida spp. e alguns isolados oportunistas incomuns como Kodamaea ohmeri, N. liquefaciens e Saitozyma podzolica. Além disso, a maioria dos isolados de Candida spp. e algumas espécies oportunistas incomuns apresentaram altos valores de concentração inibitória mínima. Conclusão: Os resultados obtidos indicam que C. albicans continua a ser a espécie predominante na cavidade oral de pacientes imunodeficientes e, juntamente com outras espécies incomuns, pode apresentar alta resistência aos antifúngicos testados.(AU)


Background and Objectives: Oral candidiasis has a common occurrence in immunocompromised patients. However, other emergent infections have become increasingly common. The aim of this study was to investigate the prevalence, virulence determinants and the antifungal susceptibility of yeast colonizing the mucosa of immunocompromised patients in Northeastern Brazil. Methods: Samples from sixty HIV-positive patients seen at the Specialized Service / Hospital Dia - Hospital Universitário Prof. Alberto Antunes from the Federal University of Alagoas were collected from subgingival sites and seeded on CHROMagar for presumptive confirmation of Candida spp. followed by PCR and sequencing. In addition, we tested virulence determinants, phospholipase and protease and evaluated in vitro the Minimum Inhibitory Concentration of antifungals amphotericin B and fluconazole. This project was approved by the Research Ethics Committee of the Center for Higher Studies in Maceió. Results: Approximately 63% of the patients were colonized by yeasts, with C. albicans as the predominant species, while non-Candida albicans species accounted for 49% of the isolates, with C. dubliniensis and C. parapsilosis being the commonest, but C. intermedia, Bullera penniseticola and Naganishia liquefaciens were also found. The virulence determinants protease and/or phospholipase were also produced by Candida spp. and some uncommon opportunistic isolates such as Kodamaea ohmeri, N. liquefaciens and Saitozyma podzolica. Furthermore, most of Candida spp. strains and some uncommon opportunistic species showed high values of minimal inhibitory concentration. Conclusion: Results obtained indicate that C. albicans continues to be the predominant species in oral cavity of immunodeficient patients and along with other unusual species may present high resistance to the antifungals tested.(AU)


Justificación y Objetivos: La candidiasis oral acomete con frecuencia a pacientes inmunocomprometidos. Sin embargo, otras infecciones emergentes se han vuelto cada vez más comunes. El objetivo de este estudio fue investigar la prevalencia, la producción de determinantes de virulencia y la susceptibilidad a antifúngicos de levaduras que colonizan la mucosa de pacientes inmunocomprometidos en la región Nordeste de Brasil. Métodos: Se colectaron muestras de sesenta pacientes VIH positivos atendidos en el Servicio de Atención Especializado/Hospital Día del Hospital Universitario Prof. Alberto Antunes, vinculado a la Universidad Federal de Alagoas. Se colectaron las muestras en las regiones subgingivales y las sembraron en CHROMagar para la presunta confirmación de Candida spp. seguido de PCR y secuenciación. Además, analizamos los determinantes de virulencia fosfolipasa y proteasa y evaluamos in vitro la concentración mínima inhibitoria de los antifúngicos anfotericina B y fluconazol. Este proyecto fue aprobado por el Comité de Ética en Investigación del Centro de Estudios Superiores de Maceió. Resultados: Aproximadamente el 63% de los pacientes fueron colonizados por levaduras, y la C. albicans fue la especie predominante, mientras que las especies de Candida no-albicans representaron el 49% de los aislamientos, de las cuales la C. dubliniensis y la C. parapsilosis fueron las más comunes. Sin embargo, también se encontraron C. intermedia, Bullera penniseticola y Naganishia liquefaciens. Los determinantes de virulencia de proteasa y/o fosfolipasa también fueron producidos por Candida spp. y algunos aislados oportunistas inusuales como Kodamaea ohmeri, N. liquefaciens y Saitozyma podzolica. Además, la mayoría de los asilados de Candida spp. y algunas especies oportunistas inusuales mostraron valores altos de concentración mínima inhibitoria. Conclusión: Los resultados obtenidos indican que C. albicans continúa siendo la especie predominante en la cavidad oral de pacientes inmunodeprimidos y, junto con otras especies poco comunes, puede presentar una alta resistencia a los antifúngicos evaluados.(AU)


Subject(s)
Humans , Virulence , Yeasts/virology , Candida , Candidiasis, Oral , Virulence Factors , Immunologic Deficiency Syndromes , Antifungal Agents , Prevalence , Acquired Immunodeficiency Syndrome
9.
Electron. j. biotechnol ; 46: 55-64, jul. 2020. tab, graf
Article in English | LILACS | ID: biblio-1223246

ABSTRACT

BACKGROUND: Ethanol concentration (PE), ethanol productivity (QP) and sugar consumption (SC) are important values in industrial ethanol production. In this study, initial sugar and nitrogen (urea) concentrations in sweet sorghum stem juice (SSJ) were optimized for high PE (≥10%, v/v), QP, (≥2.5 g/L·h) and SC (≥90%) by Saccharomyces cerevisiae SSJKKU01. Then, repeated-batch fermentations under normal gravity (NG) and high gravity (HG) conditions were studied. RESULTS: The initial sugar at 208 g/L and urea at 2.75 g/L were the optimum values to meet the criteria. At the initial yeast cell concentration of ~1 × 108 cells/mL, the PE, QP and SC were 97.06 g/L, 3.24 g/L·h and 95.43%, respectively. Repeated-batch fermentations showed that the ethanol production efficiency of eight successive cycles with and without aeration were not significantly different when the initial sugar of cycles 2 to 8 was under NG conditions (~140 g/L). Positive effects of aeration were observed when the initial sugar from cycle 2 was under HG conditions (180­200 g/L). The PE and QP under no aeration were consecutively lower from cycle 1 to cycle 6. Additionally, aeration affected ergosterol formation in yeast cell membrane at high ethanol concentrations, whereas trehalose content under all conditions was not different. CONCLUSION: Initial sugar, sufficient nitrogen and appropriated aeration are necessary for promoting yeast growth and ethanol fermentation. The SSJ was successfully used as an ethanol production medium for a high level of ethanol production. Aeration was not essential for repeated-batch fermentation under NG conditions, but it was beneficial under HG conditions.


Subject(s)
Saccharomyces cerevisiae/metabolism , Sorghum/chemistry , Ethanol/metabolism , Saccharomyces cerevisiae/growth & development , Urea , Yeasts/growth & development , Aeration , Sorghum/microbiology , Ethanol/analysis , Sugars , Juices , Fermentation , Gravitation , Nitrogen
10.
Electron. j. biotechnol ; 46: 14-21, jul. 2020. tab, graf, ilus
Article in English | LILACS | ID: biblio-1223215

ABSTRACT

BACKGROUND: Biosurfactants are biomolecules that have the potential to be applied in food formulations due to their low toxicity and ability to improve sensory parameters. Considering the ability of yeasts to produce biosurfactants with food-friendly properties, the aim of the present study was to apply a biosurfactant produced by Candida utilis in the formulation of cookies. RESULTS: The biosurfactant was obtained with a yield of 24.22 ± 0.23 g/L. The characterization analysis revealed that the structure of a metabolized fatty acid with high oleic acid content (68.63 ± 0.61%), and the thermogravimetric analysis demonstrated good stability at temperatures lower than 200°C, potential for food applications. The biosurfactant also exhibited satisfactory antioxidant activity at concentrations evaluated, without cytotoxic potential for cell strains, L929 and RAW 264.7, according to the (3-(4,5-dimethylthiazol-2- yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The incorporation of the surfactant into the dough of a standard cookie formulation to replace animal fat was carried out, achieving a softer, spongier product without significantly altering the physical and physicochemical properties or energy value. CONCLUSION: The thermal stability and antioxidant activity of the biosurfactant produced by C. utilis were verified, besides the positive contribution in the texture analysis of the cookies. Therefore, this biomolecule presents itself as a potential ingredient in flour-based sweet food formulations.


Subject(s)
Surface-Active Agents/metabolism , Candida/metabolism , Food, Formulated , Cookies , Temperature , Yeasts , Food Industry , Food Additives , Antioxidants
11.
Arq. ciências saúde UNIPAR ; 24(1): 3-7, jan-abr. 2020.
Article in Portuguese | LILACS | ID: biblio-1095737

ABSTRACT

Criptococose é uma doença grave que afeta tanto imunocomprometidos quanto imunocompetentes, com isso analisar a virulência é fundamental para novas terapêuticas. Objetivo: Analisar a capacidade de virulência e susceptibilidade aos antifúngicos de Cryptococcus spp. isolados de líquor de pacientes de hospital do norte do Paraná. Métodos: A partir de dois isolados clínicos C. neoformans e C. gattii, realizou-se a confirmação da identificação. Para a virulência, avaliou-se o tamanho da cápsula, capacidade de sobrevivência após exposição a neutrófilos, produção de melanina e urease. No antifungigrama por difusão em disco utilizou-se: anfotericina B, cetoconazol, voriconazol, itraconazol e miconazol. Resultados: C. gattii destaca-se por maior desenvolvimento da cápsula além da melhor capacidade de sobreviver a fagocitose em relação ao C. neoformans. No antifungigrama, ambos os isolados se apresentam sensíveis às drogas estudadas. Conclusão: Esses achados contribuem para a compreensão das diferentes patogêneses entre C. gattii e C. neoformans.


Cryptococcosis is a serious disease that can affect both immunocompromised and immunocompetent individuals, thus the virulence analysis is fundamental for the development of new treatments. Objective: To analyze the virulence and susceptibility of Cryptococcus spp. isolated from cerebrospinal fluid of patients from a hospital in the north of Paraná. Methods: From two clinical isolates, C. neoformans and C. gattii were confirmed and identified. For virulence, capsule size, survival capacity after exposure to neutrophils, melanin production and urease were evaluated. In the disc-diffusion method, the following antifungals were used: amphotericin B, ketoconazole, voriconazole, itraconazole and miconazole Results: It was observed that C. gattii presents greater results for development of the capsule beside presenting the best ability to survive phagocytosis in relation to C. neoformans. In the disc-diffusion method, both isolates presented sensitivity to the studied drugs. Conclusion: These findings contribute to the understanding of the different pathogens between C. gattii and C. neoformans.


Subject(s)
Cryptococcosis/virology , Virulence Factors/analysis , Antifungal Agents/analysis , Phagocytosis , Urease/urine , Yeasts/virology , Capsules/analysis , Pharmaceutical Preparations , Amphotericin B/analysis , Itraconazole , Cryptococcus neoformans/virology , Agar/analysis , Cryptococcus gattii/virology , Voriconazole , Melanins/analysis , Miconazole , Neutrophils/virology
12.
Electron. j. biotechnol ; 44: 19-24, Mar. 2020. ilus, graf
Article in English | LILACS | ID: biblio-1087631

ABSTRACT

BACKGROUND: Pyruvic acid (PA), a vital α-oxocarboxylic acid, plays an important role in energy and carbon metabolism. The oleaginous yeast Yarrowia lipolytica (Y. lipolytica) has considerable potential for the production of PA. An increased NaCl concentration reportedly increases the biomass and PA yield of Y. lipolytica. RESULTS: To increase the yield of PA, the NaCl-tolerant Y. lipolytica A4 mutant was produced using the atmospheric and room temperature plasma method of mutation. The A4 mutant showed growth on medium containing 160 g/L NaCl. The PA yield of the A4 mutant reached 97.2 g/L at 120 h (0.795 g/g glycerol) in a 20-L fermenter with glycerol as the sole carbon source, which was 28.9% higher than that of the parental strain. CONCLUSION: The PA yield from Y. lipolytica can be improved by increasing its NaCl tolerance.


Subject(s)
Pyruvic Acid/metabolism , Yarrowia/genetics , Yarrowia/metabolism , Osmotic Pressure , Yeasts , Carbon/metabolism , Sodium Chloride , Bioreactors , Salt Tolerance/genetics , Fermentation , Glycerol/metabolism , Mutation
13.
Semina cienc. biol. saude ; 41(1): 3-12, jan./jun.2020. Tab, Ilus
Article in Portuguese | LILACS | ID: biblio-1224198

ABSTRACT

The tendency to replace synthetic antimicrobials for natural ones in food industry and an increase in bacterial resistance to antibiotics resulted in a necessity to find new alternatives, and essential oils are emerging as promising substitutes for synthetic chemicals in food preservation. The objective of this work was to test the antimicrobial activity of oregano (OEO) and clove (CEO) essential oils over a range of bacteria, molds and yeast of importance as pathogens or food spoilage. The antimicrobial activity of oregano and clove essential oils were analyzed by disk diffusion method and broth microdilution test (MIC) of OEO and CEO were determined for each tested microorganism. OEO and CEO were evaluated in natura (IN) and after thermal processing (TP) at 120 o C for 5 min. Both OEO and CEO presented the same inhibition zones for IN and TP samples, for all tested microorganisms, indicating that these oils can be thermally processed maintaining their antimicrobial activity. For OEO and CEO, the more sensitive microorganisms were the fungi (Aspergillus niger, Penicillium citrinum and Candida albicans), followed by Staphylococcus aureus, Bacillus cereus and Methicillin - resistant Staphylococcus aureus (MRSA); the lowest antimicrobial activities were observed against Streptococcus mutans and Enterococcus faecalis. In general, OEO resulted in higher inhibition zones and lower MIC values for all tested microorganisms, suggesting that it was more effective as an antimicrobial agent than CEO (AU)


A preferência mundial para alimentos mais saudáveis e livres de aditivos químicos pelos consumidores, associada ao aumento da resistência bacteriana, resultaram na necessidade de medidas alternativas no setor de alimentos. Os óleos correspondem a antimicrobianos naturais e constituem uma classe emergente como substitutos dos produtos químicos sintéticos na conservação de alimentos. O objetivo deste trabalho foi avaliar a atividade antimicrobiana de óleos essenciais de orégano (OEO) e cravo (CEO ) frente a bactérias, fungos e leveduras de importância no setor de alimentos. OEO e CEO foram avaliados in natura (IN) e após processamento térmico (TP) a 120 o C por 5 minutos. Para avaliar a atividade antimicrobiana frente a cada microrganismo empregou-se o método de discodifusão e o teste de microdiluição em caldo (MIC). Tanto o OEO quanto o CEO apresentaram zonas de inibição semelhantes para amostras IN e TP, indicando que a atividade antimicrobiana desses óleos são resistentes a altas temperaturas. Os microrganismos mais sensíveis para ambos os óleos essenciais foram os fungos (Aspergillus niger, Penicillium citrinum e Candida albicans), seguidos por Staphylococcus aureus, Bacillus cereus e Staphylococcus aureus resistente à meticilina (MRSA). Já as cepas Streptococcus mutans e Enterococcus faecalis apresentaram uma maior resistência frente à atividade antimicrobiana dos óleos essenciais. Em geral, os maiores halos de inibição e menores valores de MIC foram obtidos quando empregado o OEO, sugerindo uma maior atividade microbiana do mesmo quando comparado ao CEO. (AU)


Subject(s)
Oils, Volatile , Food , Anti-Bacterial Agents , Yeasts , Diffusion , Food Preservation , Fungi
14.
Braz. arch. biol. technol ; 63: e20180130, 2020. graf
Article in English | LILACS | ID: biblio-1132195

ABSTRACT

Abstract Color removal from textile effluents was evaluated using a laboratory-combined process based on an upflow anaerobic sludge blanket (UASB) reactor followed by a shallow polishing pond (SPP). The anaerobic reactor was fed with a real textile effluent, diluted 10-times in a 350 mg/L solution of pre-treated residual yeast extract from a brewery industry as nutrient source. The parameters color, COD, N-NH3 and toxicity were monitored throughout 45 days of operation. According to the results, decolorization and COD removal were highest in the anaerobic step, whereas the effluent was polished in the SPP unit. The overall efficiency of the complete UASB-SPP system for COD and color were 88 and 62%, respectively. Moreover, the N-NH3 generated by the residual yeast extract ammonification was below 5 mg/L for the final effluent. Finally, no toxicity was detected after the treatment steps, as shown by the Vibrio fischeri microscale assay.


Subject(s)
Animals , Textiles/toxicity , Waste Disposal, Fluid/methods , Water Purification/methods , Yeasts , Toxicity Tests , Bioreactors , Aliivibrio fischeri , Anaerobiosis
15.
Electron. j. biotechnol ; 37: 56-60, Jan. 2019. tab
Article in English | LILACS | ID: biblio-1051261

ABSTRACT

Heavy metals are natural elements in the Earth's crust that can enter human food through industrial or agricultural processing, in the form of fertilizers and pesticides. These elements are not biodegradable. Some heavy metals are known as pollutants and are toxic, and their bioaccumulation in plant and animal tissues can cause undesirable effects for humans; therefore, their amount in water and food should always be under control. The aim of this study is to investigate the conditions for the bioremediation of heavy metals in foods. Various physical, chemical, and biological methods have been used to reduce the heavy metal content in the environment. During the last decades, bioremediation methods using plants and microorganisms have created interest to researchers for their advantages such as being more specific and environmentally friendly. The main pollutant elements in foods and beverages are lead, cadmium, arsenic, and mercury, which have their own permissible limits. Among the microorganisms that are capable of bioremediation of heavy metals, Saccharomyces cerevisiae is an interesting choice for its special characteristics and being safe for humans, which make it quite common and useful in the food industry. Its mass production as the byproduct of the fermentation industry and the low cost of culture media are the other advantages. The ability of this yeast to remove an individual separated element has also been widely investigated. In countries with high heavy metal pollution in wheat, the use of S. cerevisiae is a native solution for overcoming the problem of solution. This article summarizes the main conditions for heavy metal absorption by S. cerevisiae.


Subject(s)
Saccharomyces cerevisiae/metabolism , Biodegradation, Environmental , Food Industry , Metals, Heavy/metabolism , Arsenic , Yeasts , Cadmium , Contaminant Removal , Absorption , Bioaccumulation , Lead , Mercury
16.
Rev. Inst. Adolfo Lutz ; 78: 1-6, dez. 2019. tab, graf
Article in Portuguese | ColecionaSUS, LILACS, ColecionaSUS, SES-SP, CONASS, SESSP-ACVSES, SESSP-IALPROD, SES-SP, SESSP-IALACERVO | ID: biblio-1150926

ABSTRACT

O objetivo deste estudo foi de avaliar a atividade antifúngica de uma solução à base de glucoprotamina (GLU) e de óleo essencial (OE) de Cymbopogon citratus. Candida tropicalis, Claviceps lusitaniae, Meyerozyma (Pichia) guilliermondii e Candida parapsilosis foram isoladas das superfícies de um hospital público de Pelotas, RS. A atividade antifúngica da GLU foi analisada nas concentrações de 0,25% a 0,0005%, e para o OE, obtido por Clevenger, foi utilizado nas concentrações de 17.500 µg/mL a 0,034 µg/mL. A análise cromatográfica foi efetuada por meio de CG/MS. A atividade anti-Candidafoi analisada pela técnica de Microdiluição em Caldo para determinar a Concentração Inibitória Mínima (CIM) e a Concentração Fungicida Mínima (CFM). A inibição pela GLU ocorreu em todas as concentrações testadas, enquanto o OE apresentou resultado de CIM que oscilou de 2846 a 5450 µg/mL, e CFM de 2853 a 5330 µg/mL. Alfa­citral (37,10%), beta­citral (32,77% e beta-mirceno (18,75%) foram considerados como os compostos majoritários do OE. Os dados obtidos neste trabalho destacam a atividade antifúngica da solução à base de GLU e do OE de C. citratus na eliminação dos isolados de Candida spp ambientais. (AU)


This study aimed at evaluating the antifungal activity of glucoprotamine solution (GLU) and the essential oil from Cymbopogon citratus (EO). Candida tropicalis, Claviceps lusitaniae, Meyerozyma(Pichia) guilliermondii and Candida parapsilosis were isolated from the samples, which were collected from the surfaces of a public hospital located in Pelotas, RS. The antifungal activity of GLU was detected at the concentrations from 0.25% to 0.0005%, while the EO, by Clevenger, was used at concentrations from 17.500 µg mL to 0.034 µg/mL. Chemical analysis was determined by GC/MS. The anti-Candida activity was performed by using Broth Microdilution technique to determine the Minimal Fungicidal Concentration (MFC) and the Minimal Inhibitory Concentration (MIC). The inhibition by GLU occurred at all of the tested concentrations, whereas the EO showed MIC ranging from 2.846 to 5.450 µ/mL and the CFM from 2.853 to 5.330 µg/mL. Alfa­citral (37.10%), beta­citral (32.77%) and beta-mirceno (18.75%) were the majority compounds in the EO. The data obtained in the present study highlight the effectiveness of the solution based on GLU and EO for eliminating the environmental isolates of Candida spp. (AU)


Subject(s)
Yeasts , Oils, Volatile , Cymbopogon , Environmental Pollution , Hospitals , Antifungal Agents
17.
Rev. chil. infectol ; 36(6): 790-793, dic. 2019. tab
Article in Spanish | LILACS | ID: biblio-1058113

ABSTRACT

Resumen La espectrometría de masas MALDI-TOF MS es una técnica rápida y sencilla para identificar microorganismos por análisis proteico. Se estudiaron 304 aislados de levaduras procedentes de micosis superficiales y profundas, con el objetivo de comparar tres métodos: convencional (bioquímico y morfológico), MALDI-TOF MS, y reacción en cadena de la polimerasa (RPC, método de referencia). Se estudiaron 24 especies con predominio de Candida spp y Cryptococcus spp. La identificación por método convencional fue de 258/304 cepas, mientras que por MALDI-TOF MS fue de: 277/304 cepas (84,8 versus 91,2%, p = no significativo). El coeficiente Kappa entre el MALDI-TOF MS y la RPC reportó una excelente concordancia (0,99). La sensibilidad y la especificidad de MALDI-TOF MS para la identificación de levaduras patógenas oportunistas de muestras clínicas fueron de 94,6% y 99%; respectivamente. MALDI-TOF MS demostró ser una herramienta de alta precisión para la identificación de levaduras patógenas.


MALDI-TOF MS mass spectrometry is a rapid and straightforward technique to identify microorganisms by protein analysis. The study was performed in 304 yeast isolates from superficial and deep mycoses, in order to compare three methods: conventional (biochemical and morphological), MALDI-TOF MS, and polymerase chain reaction (PCR, reference). We included 24 species with predominance of Candida spp and Cryptococcus spp. The identification by conventional methods was 258/304 strains, while by MALDI-TOF MS was: 277/304 strains (84.8% versus 91.2%, P = not significant). The Kappa coefficient comparing MALDI-TOF-MS with PCR reported excellent concordance (0.99). The sensitivity and specificity of MALDI-TOF MS for the diagnosis of opportunistic pathogenic yeasts of clinical samples were 94.6% and 99% respectively. MALDI-TOF MS is a simple, fast and reliable tool for pathogenic yeasts.


Subject(s)
Humans , Mycoses , Yeasts , Candida/genetics , Sensitivity and Specificity , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
18.
Electron. j. biotechnol ; 42: 1-5, Nov. 2019. tab, graf
Article in English | LILACS | ID: biblio-1087340

ABSTRACT

Background: Fermentation strategies for bioethanol production that use flocculating Saccharomyces cerevisiae yeast need to account for the mechanism by which inhibitory compounds, generated in the hydrolysis of lignocellulosic materials, are tolerated and detoxified by a yeast floc. Results: Diffusion coefficients and first-order kinetic bioconversion rate coefficients were measured for three fermentation inhibitory compounds (furfural, hydroxymethylfurfural, and vanillin) in self-aggregated flocs of S. cerevisiae NRRL Y-265. Thièle-type moduli and internal effectiveness factors were obtained by simulating a simple steady-state spherical floc model. Conclusions: The obtained values for the Thiéle moduli and internal effectiveness factors showed that the bioconversion rate of the inhibitory compounds is the dominant phenomenon over mass transfer inside the flocs.


Subject(s)
Saccharomyces cerevisiae/metabolism , Biofuels , Yeasts , Benzaldehydes , Biodegradation, Environmental , Inactivation, Metabolic , Diffusion , Flocculation , Furaldehyde/analogs & derivatives
19.
Rev. bras. anal. clin ; 51(2): 157-166, 20191011. ilus
Article in Portuguese | LILACS | ID: biblio-1024978

ABSTRACT

Objetivo: O Compêndio de Métodos e de Boas Práticas em Coleção de Cultura de Leveduras do Instituto de Biologia do Exército (IBEx) foi elaborado com o propósito de operacionalizar as atividades de pesquisa, garantindo o desempenho seguro e confiável dos seus objetivos regimentais. Métodos: A Coleção de Cultura de Leveduras do IBEx foi criada a partir de cepas isoladas de quadros de candidíase sistêmica, através da utilização de metodologias manuais e automatizadas para autenticação das mesmas, com o propósito de garantir a pesquisa científica e atividades de ensino. Resultados: O Instituto adequou e modernizou seus laboratórios de pesquisa criando o Centro de Estudos em Biodefesa, com Nível de Biossegurança NB-3. Com base na necessidade de organização para atender às demandas da defesa biológica, o IBEx vem aprimorando sua estrutura para dominar e garantir novas tecnologias de identificação e manejo dos microrganismos envolvidos em Bioterrorismo. Conclusão: A compilação de metodologias na forma de um Compêndio proporcionou a operacionalização da Coleção de Cultura do IBEx.


Objective: The Compendium of Methods and Good Practices in Yeast Culture Collection of the Brazilian Army Biology Institute (IBEx) was elaborated with the purpose of operationalizing the research activities, guaranteeing the safe and reliable performance of its regimental objectives. Methods: The IBEx Yeast Culture Collection was created from isolated strains of systemic candidiasis, through the use of manual and automated methodologies to authenticate them, in order to guarantee scientific research and teaching activities. Results: The Institute adapted and modernized its research laboratories by creating the Center for Biodefense Studies, with Biosafety Level NB-3. Based on the need for organization to meet the demands of biological defense, the IBEx has been improving its structure to dominate and guarantee new technologies of identification and management of the microorganisms involved in Bioterrorism. Conclusion: The compilation of methodologies in the form of a Compendium provided the operationalization of the IBEx Culture Collection


Subject(s)
Yeasts , Clinical Laboratory Techniques , Scientific Research and Technological Development , Blood Culture , Candidiasis , Polymerase Chain Reaction
20.
Electron. j. biotechnol ; 41: 13-21, sept. 2019. ilus, graf, tab
Article in English | LILACS | ID: biblio-1053560

ABSTRACT

Background: Sugars from sweet sorghum stalks can be used to produce ethanol and also to grow oleaginous yeasts. Instead of two separate processes, in this paper we propose a different route producing ethanol and microbial oil in two consecutive fermentation steps. Results: Three yeasts were compared in the first ethanol producing step. In the second step four different oleaginous yeasts were tested. Sweet sorghum juice was first clarified and concentrated. High gravity ethanol fermentation was carried out with concentrated juice with 23.7 g/100 mL of total sugars and without added nutrients. Total sugars were 2.5 times more than the original clarified juice. One yeast gave the best overall response over the two other tested; relative high ethanol productivity, 1.44 g ethanol/L•h−1 , and 90% of sugar consumption. Aeration by flask agitation produced superior results than static flasks for all yeasts. Microbial oil production was done employing the residual liquid left after ethanol separation. The pooled residual liquid from the ethanol distillation contained 7.08 g/mL of total carbohydrates, rich in reducing sugars. Trichosporon oleaginosus and Lipomyces starkeyi produced higher dry biomass, total sugar consumption and oil productivity than the other two oleaginous yeasts tested; with values around 25 g/L, 80%, and 0.55 g oil/L•h−1 respectively. However, the biomass oil content in all yeasts was relatively low in the range of 14 to 16%. Conclusion: The two step process is viable and could be considered an integral part of a consolidated biorefinery from sweet sorghum.


Subject(s)
Sorghum/chemistry , Ethanol/metabolism , Fruit and Vegetable Juices , Saccharomyces cerevisiae , Yeasts , Trichosporon , Sugars , Juices , Lipomyces , Biofuels/microbiology , Fermentation
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