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1.
J Basic Microbiol ; 64(2): e2300444, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38051942

RESUMEN

The aim of this study was to investigate the production, stability and applicability of colorants produced by filamentous fungi isolated from soil samples from the Amazon. Initially, the isolates were evaluated in a screening for the production of colorants. The influences of cultivation and nutritional conditions on the production of colorants by fungal isolates were investigated. The colorants produced by selected fungal isolates were chemically characterized using the Liquid Chromatography-Mass Spectrometry technique. The antimicrobial and cytotoxic activities, stability evaluation and applicability of the colorants were investigated. As results, we observed that the isolates Penicillium sclerotiorum P3SO224, Clonostachys rosea P2SO329 and Penicillium gravinicasei P3SO332 stood out since they produced the most intense colorants. Compounds produced by Penicillium sclerotiorum P3SO224 and Clonostachys rosea P2SO329 were identified as sclerotiorin and penicillic acid. The colorant fraction (EtOAc) produced by these species has antimicrobial activity, stability at temperature and at different pHs, stability when exposure to light and UV, and when exposed to different concentrations of salts, as well as being nontoxic and having the ability to dye fabrics and be used as a pigment in creams and soap. Considering the results found in this study, it was concluded that fungi from the soil in the Amazon have the potential to produce colorants with applications in the textile and pharmaceutical industries.


Asunto(s)
Antiinfecciosos , Hypocreales , Penicillium , Pigmentos Biológicos/química , Hongos/química , Suelo
2.
Foods ; 11(11)2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35681401

RESUMEN

Cassava is an important staple food for low-income countries. However, its cooking characteristics are especially affected by genotype. In this study, two groups of genotypes, namely hard to cook (HTC) and easy to cook (ETC), were harvested at different times (9 and 15 months), and evaluated by NMR coupled to chemometrics. Additionally, lignin of these materials was studied by 1H-13C HSQC NMR. The carbohydrates were the most important class of compounds to differentiate the cassava genotypes. The correlation of NMR with cooking time and starch content showed that the higher content of primary metabolites, mostly glucose, can be associated with longer cooking times and reduction of starch, corroborating the metabolic pathways analysis. Furthermore, it was observed that the lignin from cell walls did not differentiate the cooking performance of the genotypes.

3.
Pesqui. vet. bras ; 37(11): 1241-1246, Nov. 2017. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-895371

RESUMEN

The processing of Manihot esculenta (cassava) tubers yield different by-products, including cassava wastewater, which is the liquid pressed out of the tuber after it has been mechanically crushed. Cyanide poisoning after ingestion of cassava wastewater has been reported in ruminants and pigs in Northeastern Brazil. With the aim of studying its toxicity, cassava wastewater was administered orally to six sheep at doses of 0.99, 0.75, 0.70, 0.63, and 0.5 mg of hydrocyanic acid kg-1 body weight, which corresponded to 14.2, 10.6, 9.8, 8.89, and 7.1 mL of wastewater kg-1. On the second day, the sheep received a volume of wastewater which corresponded to 0.46, 0.34, 0.31, 0.28, and 0.23 mg of HCN kg-1. A sheep used as control received 9.9 mL of water kg-1 BW. Sheep that received from 0.75 to 0.99 mg kg-1 of HCN on the first day exhibited severe clinical signs of poisoning, and the sheep that received 0.63 and 0.5 mg kg-1 exhibited mild clinical signs. All sheep were successfully treated with sodium thiosulfate. On the second day, only the sheep that received 0.46 mg kg-1 and 0.34 mg kg-1 exhibited mild clinical signs and recovered spontaneously. The concentration of HCN in the wastewater was 71.69±2.19 μg mL-1 immediately after production, 30.56±2.45 μg mL-1 after 24 hours, and 24.25±1.28 μg mL-1 after 48 hours. The picric acid paper test was strongly positive 5 minutes after production; moderately positive 24 hours after production, and negative 48 hours after production. We conclude that cassava wastewater is highly toxic to sheep if ingested immediately after production, but rapidly loses toxicity in 24-48 hours.(AU)


O processamento dos tubérculos de Manihot esculenta (mandioca) produzem diferentes subprodutos, incluindo a manipueira, líquido que escorre das raízes da mandioca depois de ter sido mecanicamente prensada. A intoxicação por cianeto após a ingestão de manipueira tem sido relatada em ruminantes e suínos no Nordeste do Brasil. Com o objetivo de estudar sua toxicidade, administrou-se manipueira por via oral a seis ovelhas em doses de 0,99, 0,75, 0,70, 0,63 e 0,5 mg de peso corporal de ácido cianídrico kg-1, correspondendo a 14,2, 10,6, 9,8, 8,89 e 7,1 mL de manipueira kg-1 de peso corporal. No segundo dia, as ovelhas receberam um volume de manipueira que correspondeu a 0,46, 0,34, 0,31, 0,28 e 0,23 mg de HCN kg-1. Uma ovelha usada como controle recebeu 9,9 mL de água kg-1 de peso corporal. Ovelhas que receberam doses de 0,75 a 0,99 mg kg-1 de HCN no primeiro dia exibiram sinais clínicos graves de intoxicação e as ovelhas que receberam 0,63 e 0,5 mg kg-1 exibiram sinais clínicos leves. Todas as ovelhas foram tratadas com sucesso com tiossulfato de sódio. No segundo dia, apenas as ovelhas que receberam 0,46 mg kg-1 e 0,34 mg kg-1 apresentaram sinais clínicos leves e se recuperaram espontaneamente. A concentração de HCN na manipueira foi de 71,69 ± 2,19 μg mL-1 imediatamente após a produção, 30,56 ± 2,45 μg mL-1 após 24 horas e 24,25 ± 1,28 μg mL-1 após 48 horas. O teste de papel picrosódico foi fortemente positivo 5 minutos após a produção; moderadamente positivo 24 horas após a produção e negativo 48 horas após a produção. Concluímos que a manipueira é altamente tóxica para ovinos se ingeridas imediatamente após a produção, mas rapidamente perdem toxicidade em 24-48 horas.(AU)


Asunto(s)
Animales , Manihot/toxicidad , Oveja Doméstica , Enfermedades Transmitidas por los Alimentos/veterinaria , Cianuro de Hidrógeno/toxicidad
4.
Eur J Med Chem ; 141: 188-196, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29031066

RESUMEN

Histone deacetylase inhibitors (HDACis) play an important role as valuable drugs targeted to cancer therapy: several HDACis are currently being tested in clinical trials. Two new potential HDACis 1a and 1d, characterized by the presence of a biphenyl-4-sulfonamide group as a connection unit between the N-{4-[(E)-(2-formylhydrazinylidene)methyl]-3-hydroxyphenyl} and the 2-hydroxy-N-(trifluoroacetyl)benzamide moiety, respectively, as two zinc-binding group (ZBG), have been designed, synthesized and tested for their biological activity. Surprisingly, compounds 1a and 12, this last exclusively obtained in place of 1d, exhibited a very low HDAC inhibitory activity. A serendipitous assay of these two compounds, conducted on three chemoresistant cell lines of head and neck squamous cell carcinoma (HNSCC), showed their antiproliferative activity at low nanomolar concentrations, better than cisplatin. In vitro, biological assays indicated that compounds 1a and 12 are able to increase acetylation of histone H3 and to interfere with the PI3K/Akt/mTOR pathway by inducing the accumulation of PTEN protein.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Células Escamosas/tratamiento farmacológico , Descubrimiento de Drogas , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Inhibidores de Histona Desacetilasas/farmacología , Sulfonamidas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Carcinoma de Células Escamosas/patología , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Neoplasias de Cabeza y Cuello/patología , Inhibidores de Histona Desacetilasas/síntesis química , Inhibidores de Histona Desacetilasas/química , Humanos , Estructura Molecular , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/química
5.
Bioresour Technol ; 97(6): 862-7, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15953719

RESUMEN

Five agricultural wastes were evaluated in submerged fermentation for xylanolytic enzymes production by Penicillium janthinellum. The wastes were hydrolyzed in acid medium and the liquid fraction was used for cultivation. Corn cob (55.3 U/mL) and oat husk (54.8 U/mL) were the best inducers of xylanase. Sugar cane bagasse (23.0 U/mL) and corn husk (23.8 U/mL) were moderately good, while cassava peel was negligible. Protease production was very low in all agro-industrial residues. The maximum biomass yields were 1.30 and 1.17 g/L for cassava peel and corn husk after 180 h, respectively. Xylanolytic activity showed a cell growth associated profile.


Asunto(s)
Agricultura/métodos , Endo-1,4-beta Xilanasas/metabolismo , Residuos Industriales , Penicillium/metabolismo , Péptido Hidrolasas/metabolismo , Avena/metabolismo , Biomasa , Medios de Cultivo , Fermentación , Concentración de Iones de Hidrógeno , Microbiología Industrial/métodos , Manihot/metabolismo , Zea mays/metabolismo
6.
Biotechnol Prog ; 20(6): 1880-4, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15575727

RESUMEN

Cultivation of the fungus Penicillium janthinellum for xylanase production was studied in a poly(ethylene glycol)/cashew-nut tree gum aqueous two-phase system, using a two-level fractional factorial design. The parameters studied were initial pH, cultivation time, type of agro-industrial residue (oat husk or corn cob), agitation, temperature, and phase-forming polymers. The xylanase produced during fermentation partitioned into the top phase. The agitation and temperature (negative), cultivation time and initial pH (positive) effects proved statistically significant for xylanase production. The highest percentage yield of the xylanase in the top and its production in the top phase, about 97% and 160.7 U/mL, were obtained in cultures of 120 h, 40 rpm, 25 degrees C, and pH 5.0.


Asunto(s)
Anacardium/química , Técnicas de Cultivo de Célula/métodos , Fraccionamiento Químico/métodos , Endo-1,4-beta Xilanasas/biosíntesis , Endo-1,4-beta Xilanasas/aislamiento & purificación , Penicillium/enzimología , Polietilenglicoles/química , Reactores Biológicos/microbiología , Endo-1,4-beta Xilanasas/química , Activación Enzimática , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Extractos Vegetales/química , Temperatura
7.
Phytother Res ; 18(8): 634-9, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15476304

RESUMEN

Bidens pilosa (Asteraceae), a medicinal plant used worldwide, has antimalarial activity as shown in previous work. This study tested ethanol extracts from wild plants collected in three different regions of Brazil and from plants cultivated in various soil conditions. The extracts were active in mice infected with P. berghei: doses of < or =500 mg/kg administered by oral route reduced malaria parasitaemia and mouse mortality; higher doses were found to be less effective. Tested in vitro against three P. falciparum isolates, two chloroquine resistant and one mefloquine resistant, the plants cultivated under standard conditions, and in humus enriched soil, were active; but the wild plants were the most active. Analysis using thin layer chromatography demonstrated the presence of flavonoids (compounds considered responsible for the antimalarial activity) in all plants tested, even though at different profiles. Because B. pilosa is proven to be active against P. falciparum drug-resistant parasites in vitro, and in rodent malaria in vivo, it is a good candidate for pre-clinical tests as a phytotherapeutic agent or for chemical isolation of the active compounds with the aim of finding new antimalarial drugs.


Asunto(s)
Antimaláricos/farmacología , Bidens , Malaria Falciparum/prevención & control , Fitoterapia , Extractos Vegetales/farmacología , Plasmodium berghei/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Animales , Antimaláricos/administración & dosificación , Antimaláricos/uso terapéutico , Resistencia a Medicamentos , Ratones , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Raíces de Plantas , Suelo
8.
Mem Inst Oswaldo Cruz ; 98(5): 599-603, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-13677340

RESUMEN

A survey was conducted in the hemodialysis population of the state of Tocantins, Brazil, aiming to assess the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, to analyze associated risk factors, and also to investigate these viruses genotypes distribution. During January and March 2001, all patients (n = 100) were interviewed at the unique dialysis unit in Tocantins. Blood samples were collected and serum samples were screened for HBV serological markers. Hepatitis B surface antigen positive samples were tested for HBV DNA. All samples were also tested for anti-HCV antibodies and HCV RNA. An overall prevalence of 45% was found for HBV infection (4% were HBsAg/anti-HBc positive, 2% were anti-HBc only and 39% had anti-HBc/anti-HBs markers). Concerning HCV infection, anti-HCV and HCV RNA were detected in 13% and 14% of the subjects, respectively. Three patients were HCV RNA positive and anti-HCV negative, resulting in an overall HCV prevalence of 16%. Univariate analysis of risk factors showed that only shift and length of tile on hemodialysis were associated with HBV and HCV positivity respectively. Among the four HBsAg-positive samples, HBV DNA was detected in three of them, which were identified as genotype A by restriction fragment length polymorphism (RFLP) analysis. All 14HCV RNA-positive samples were genotyped by INNO-LiPA. Genotypes la and 3a were found in 85% and 15%, respectively. The present data show low HBsAg and HCV prevalence rates. The risk factors associated with HBV and HCV positivity suggest that nosocomial transmission may influence in spreading these viruses in the dialysis unit studied.


Asunto(s)
Hepatitis B/epidemiología , Hepatitis C/epidemiología , Diálisis Renal/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Brasil/epidemiología , Femenino , Genotipo , Hepacivirus/inmunología , Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Hepatitis C/sangre , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , ARN Viral/sangre , Factores de Riesgo
9.
Mem. Inst. Oswaldo Cruz ; 98(5): 599-603, July 2003. tab, graf
Artículo en Inglés | LILACS | ID: lil-344276

RESUMEN

A survey was conducted in the hemodialysis population of the state of Tocantins, Brazil, aiming to assess the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, to analyze associated risk factors, and also to investigate these viruses genotypes distribution. During January and March 2001, all patients (n = 100) were interviewed at the unique dialysis unit in Tocantins. Blood samples were collected and serum samples were screened for HBV serological markers. Hepatitis B surface antigen positive samples were tested for HBV DNA. All samples were also tested for anti-HCV antibodies and HCV RNA. An overall prevalence of 45 percent was found for HBV infection (4 percent were HBsAg/anti-HBc positive, 2 percent were anti-HBc only and 39 percent had anti-HBc/anti-HBs markers). Concerning HCV infection, anti-HCV and HCV RNA were detected in 13 percent and 14 percent of the subjects, respectively. Three patients were HCV RNA positive and anti-HCV negative, resulting in an overall HCV prevalence of 16 percent. Univariate analysis of risk factors showed that only shift and length of time on hemodialysis were associated with HBV and HCV positivity, respectively. Among the four HBsAg-positive samples, HBV DNA was detected in three of them, which were identified as genotype A by restriction fragment length polymorphism (RFLP) analysis. All 14 HCV RNA-positive samples were genotyped by INNO-LiPA. Genotypes 1a and 3a were found in 85 percent and 15 percent, respectively. The present data show low HBsAg and HCV prevalence rates. The risk factors associated with HBV and HCV positivity suggest that nosocomial transmission may influence in spreading these viruses in the dialysis unit studied


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Hemodiálisis en el Domicilio , Hepacivirus , Hepatitis B , Virus de la Hepatitis B , Hepatitis C , Anciano de 80 o más Años , Biomarcadores , Brasil , Ensayo de Inmunoadsorción Enzimática , Genotipo , Hepacivirus , Hepatitis B , Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B , Hepatitis C , Anticuerpos contra la Hepatitis C , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , Factores de Riesgo , ARN Viral
10.
Mem Inst Oswaldo Cruz ; 97(7): 953-7, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12471420

RESUMEN

A survey was conducted in a blood donor population of Central Brazil aiming to investigate the prevalence of GB virus C (GBV-C)/hepatitis G virus (HGV) infection and also to analyze the virus genotypes distribution. A total of 241 voluntary blood donors were interviewed at the State Blood Bank in Goiânia, State of Goiás, Brazil. Blood samples were collected and serum samples tested for GBV-C/HGV RNA by polymerase chain reaction. Genotypes were determined by restriction fragment length polymorphism (RFLP) analysis. Seventeen samples were GBV-C/HGV RNA-positive, resulting in a prevalence of 7.1% (95% CI: 4.2-11.1). A significant trend of GBV-C/HGV RNA positivity in relation to age was observed, with the highest prevalence in donors between 29-39 years old. Ten infected individuals were characterized by reporting parenteral (30%), sexual (18%), both (6%) and intrafamiliar (6%) transmission. However, 7 (40%) GBV-C/HGV RNA-positive donors did not mention any potential transmission route. RFLP analysis revealed the presence of genotypes 1 and 2 of GBV-C/HGV; more precisely, 10 (58.9%) samples were found belonging to the 2b subtype, 4 (23.5%) to the 2a subtype, and 3 (17.6%) to genotype 1. The present data indicate an intermediate endemicity of GBV-C/HGV infection among this blood donor population, and a predominant circulation of genotype 2 (subtype 2b) in Central Brazil.


Asunto(s)
Donantes de Sangre , Infecciones por Flaviviridae/epidemiología , Virus GB-C/genética , Hepatitis Viral Humana/epidemiología , Adolescente , Adulto , Brasil/epidemiología , Distribución de Chi-Cuadrado , Intervalos de Confianza , Femenino , Infecciones por Flaviviridae/virología , Genotipo , Hepatitis Viral Humana/virología , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , ARN Viral/análisis
11.
Mem. Inst. Oswaldo Cruz ; 97(7): 953-957, Oct. 2002. tab, graf
Artículo en Inglés | LILACS | ID: lil-325920

RESUMEN

A survey was conducted in a blood donor population of Central Brazil aiming to investigate the prevalence of GB virus C (GBV-C)/hepatitis G virus (HGV) infection and also to analyze the virus genotypes distribution. A total of 241 voluntary blood donors were interviewed at the State Blood Bank in Goiânia, State of Goiás, Brazil. Blood samples were collected and serum samples tested for GBV-C/HGV RNA by polymerase chain reaction. Genotypes were determined by restriction fragment length polymorphism (RFLP) analysis. Seventeen samples were GBV-C/HGV RNA-positive, resulting in a prevalence of 7.1 percent (95 percent CI: 4.2-11.1). A significant trend of GBV-C/HGV RNA positivity in relation to age was observed, with the highest prevalence in donors between 29-39 years old. Ten infected individuals were characterized by reporting parenteral (30 percent), sexual (18 percent), both (6 percent) and intrafamiliar (6 percent) transmission. However, 7 (40 percent) GBV-C/HGV RNA-positive donors did not mention any potential transmission route. RFLP analysis revealed the presence of genotypes 1 and 2 of GBV-C/HGV; more precisely, 10 (58.9 percent) samples were found belonging to the 2b subtype, 4 (23.5 percent) to the 2a subtype, and 3 (17.6 percent) to genotype 1. The present data indicate an intermediate endemicity of GBV-C/HGV infection among this blood donor population, and a predominant circulation of genotype 2 (subtype 2b) in Central Brazil


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Donantes de Sangre , Infecciones por Flaviviridae , Virus GB-C/genética , Hepatitis Viral Humana , Brasil , Distribución de Chi-Cuadrado , Intervalos de Confianza , Infecciones por Flaviviridae , Genotipo , Hepatitis Viral Humana , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , ARN Viral
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