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1.
Yeast ; 40(12): 640-650, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37997429

RESUMEN

Yeasts have been widely used as a model to better understand cell cycle mechanisms and how nutritional and genetic factors can impact cell cycle progression. While nitrogen scarcity is well known to modulate cell cycle progression, the relevance of nitrogen excess for microorganisms has been overlooked. In our previous work, we observed an absence of proper entry into the quiescent state in Hanseniaspora vineae and identified a potential link between this behavior and nitrogen availability. Furthermore, the Hanseniaspora genus has gained attention due to a significant loss of genes associated with DNA repair and cell cycle. Thus, the aim of our study was to investigate the effects of varying nitrogen concentrations on H. vineae's cell cycle progression. Our findings demonstrated that nitrogen excess, regardless of the source, disrupts cell cycle progression and induces G2/M arrest in H. vineae after reaching the stationary phase. Additionally, we observed a viability decline in H. vineae cells in an ammonium-dependent manner, accompanied by increased production of reactive oxygen species, mitochondrial hyperpolarization, intracellular acidification, and DNA fragmentation. Overall, our study highlights the events of the cell cycle arrest in H. vineae induced by nitrogen excess and attempts to elucidate the possible mechanism triggering this absence of proper entry into the quiescent state.


Asunto(s)
Hanseniaspora , Hanseniaspora/metabolismo , Apoptosis , Puntos de Control de la Fase G2 del Ciclo Celular , Línea Celular Tumoral , Nitrógeno/metabolismo
2.
Sci Rep ; 13(1): 9781, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328566

RESUMEN

The conventional methods for ethanol recovery in low concentrations from diluted aqueous solutions are limited by the high energy consumed. Therefore, developing a cost-effective advanced membrane process for ethanol recovery and concentration is still necessary. A gas stripping-assisted vapour permeation (GSVP) process was applied to concentrate ethanol by the selective removal of water using hydrophilic graphene oxide (GO) membranes. Silicon carbide porous tubes were internally coated with GO-based membranes with an average thickness of 1.1 µm as a selective layer. Dry N2 was bubbled into the feed solution, carrying the saturated vapours to the separation module. The modified GSVP process was implemented to recover ethanol at lower temperatures than direct distillation and close-ended GSVP processes. The performance of the membrane-coated tubes was evaluated as a function of temperature and feed concentration, ranging from 23 to 60 °C and 10 wt% to 50 wt%. Distillates with 67 wt% and 87 wt% were obtained from feeds with 10 and 50 wt% ethanol at 50 °C, respectively. The evaporation energy spent by the modified GSVP process using GO-coated SiC tubes was 22% and 31% lower than the traditional distillation and vapour stripping processes.


Asunto(s)
Etanol , Grafito , Agua , Gases
3.
J Ethnopharmacol ; 298: 115564, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-35940467

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Matcha green tea (Camellia sinensis) based-supplements have been widely used since they present a greater content of phenolic compounds than traditional green tea, which is popularly used in the treatment of diabetes. However, there are few studies on the effectiveness and safety of matcha supplements. AIM OF THE STUDY: This work aimed to evaluate the efficacy and safety of this supplement in endothelial cells (EA.hy926) in the hyperglycemic model and in vivo Artemia salina. MATERIALS AND METHODS: To assess the effect of Matcha herbal supplement (MHS), EA. hy926 endothelial cells were treated with 20 µg/mL of MHS for 24 h, in a hyperglycemic medium with 35 mM glucose. After treatment, cells were trypsinized and centrifuged at 4 °C and 47×g for 5 min. The pellet was used to determine the reaction products to thiobarbituric acid and the levels of nitric oxide. Electron transport chain activity and ATP levels were also evaluated. Intracellular pH, apoptosis, and mitochondrial membrane depolarization were evaluated by flow cytometry. MHS chemical characterization was performed by HPLC-UV and total phenolic content analysis. The evaluation of the antioxidant capacity of MHS was performed by 2,2-diphenyl-1-picrylhydrazyl radical scavenger assay. To determine the in vivo acute toxicity of MHS, an A. salina assay was conducted, using 0,2 mL of different concentrations of MHS (10, 50, 100, 250, 500, 750 and 1000 µg/mL). The LD50 values were obtained by interpolation of 50% (y = 50) of the dead individuals in the trend curves. RESULTS: Our data showed that MHS was able to avoid oxidative and nitrosative stress induced by hyperglycemia, demonstrating important antioxidant activity. However, it was observed that MHS reduced up to 90% the activity of the four-electron transport complexes, reducing the ATP production of the endothelial cells. In the toxicity assay performed in Artemia salina, MHS showed mild toxicity (LD50 = 0,4 mg/mL). The major compounds found in MHS were epigallocatechin gallate, epicatechin, rutin, kaempferol, and quercetin. CONCLUSIONS: This data draws attention to the fact that supplements with high content of phenolic compounds, capable of avoiding oxidative and nitrosative stress can have a dual effect and, simultaneously to antioxidant activity, can induce toxicity in different cell types.


Asunto(s)
Camellia sinensis , Adenosina Trifosfato , Animales , Antioxidantes/análisis , Antioxidantes/farmacología , Artemia , Camellia sinensis/química , Suplementos Dietéticos/análisis , Suplementos Dietéticos/toxicidad , Células Endoteliales , Humanos , Fenoles/análisis , Fenoles/toxicidad , Té/química
4.
J Neurosurg Sci ; 2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35380199

RESUMEN

BACKGROUND: Degenerative disc disease (DDD) is a prevalent disorder that brings great incapacity and morbidity to the world's population. Its pathophysiology is not fully understood. DNA damage can influence this process, but so far, there have been few studies to evaluate this topic and its true importance in DDD, as well as whether there is a relation between degeneration grade and DNA damage. The objective of this study is to evaluate the degree of damage to the DNA and the relation to the severity of DDD and measure its response to this insult compared to live/dead cell parameters and reactive oxygen species activity in human discs. METHODS: An experimental study was performed with 15 patients with grade IV or V Pfirrmann classification who underwent spinal surgery. Five patients were operated on two levels, resulting in 20 samples that were submitted to the comet assay to measure DNA damage. Of these, six samples were submitted to flow cytometry, and apoptosis, necrosis, cell membrane integrity, intracellular esterase activity, reactive oxygen species (ROS), caspase 3 and mitochondrial membrane potential were evaluated. RESULTS: All samples had DNA damage, and the average of index damage (ID) was 78.1 (SD ± 65.11) and frequency damage (FD) was 49.3% (SD ± 26,05%). There was no statistical difference between the Pfirrmann grades and genotoxic damage. Likewise, all samples that underwent flow cytometry showed apoptosis and ROS to many different degrees. CONCLUSIONS: DNA damage occurs in high-grade degeneration of human discs and contributes to activation of the apoptosis pathway and ROS production that can accelerate disc degeneration.

5.
An Acad Bras Cienc ; 94(2): e20200394, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35319598

RESUMEN

Alternaria alternata causes leaf spot and black rot diseases in leaves and grapes of grapevines, respectively, and leads to huge economic losses in table grapes production. As natural antifungal agents, essential oils (EOs), which are generally recognized as safe substances, shows strong antifungal activity against fungal phytopathogens. The aim of this study was to determine the chemical composition of Eucalyptus staigeriana EO and its in vitro and in vivo effects against A. alternata. The major compounds of E. staigeriana EO were citral (34.32%, of which 21.83% geranial and 12.49% neral), limonene (20.60%) and 1,8-cineole (12.33%). E. staigeriana EO exhibited the highest inhibitory activity on mycelial growth and conidial germination at 1 µL mL-1. Moreover, the EO was able to reduce the incidence and severity of leaf spot disease in leaves and black rot disease in table grapes caused by A. alternata. These results represent a possible alternative to reduce the use of synthetic molecules for the control of diseases in postharvest of table grapes and in vineyard.


Asunto(s)
Eucalyptus , Aceites Volátiles , Vitis , Alternaria , Antifúngicos/química , Antifúngicos/farmacología , Aceites Volátiles/farmacología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control
6.
Food Chem ; 326: 126997, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32422511

RESUMEN

The increased demand for pesticide-free foods has also increased the search for healthier and environmentally friendly alternatives in agriculture. Essential oils are known to possess natural antifungal properties, becoming a reliable alternative for commercial fungicides, especially for postharvest decay control. However, essential oils are volatile and photodegradable, which reduces their long-term activities. This work presents the development of a lemongrass essential oil-containing poly(lactic acid) nanocapsules. They have shown in vitro antifungal activity against Colletotrichum acutatum and Colletotrichum gloeosporioides with a MIC dosage of 0.1% (v/v) for both phytopathogens. In the in vivo assay with postharvest apples, the ones treated with encapsulated essential oil showed bitter rot lesions three times smaller than the ones treated with non-encapsulated essential oil, or in comparison to the apples in positive control. The methodology led to stable nanocapsules with spherical morphology, a mean diameter of 96.4 nm, and with an encapsulation efficiency of 99%.


Asunto(s)
Antifúngicos/farmacología , Colletotrichum/efectos de los fármacos , Cymbopogon/química , Fungicidas Industriales/farmacología , Nanocápsulas/química , Aceites Volátiles/química , Poliésteres/farmacología , Malus/efectos de los fármacos , Malus/microbiología , Poliésteres/química
7.
Braz. arch. biol. technol ; Braz. arch. biol. technol;63: e20190481, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1132242

RESUMEN

Abstract The objective of this study was to evaluate the biomass and essential oil production of nine populations of poejo (Cunila galioides) cultivated in five agroecological regions of the state of Rio Grande do Sul, under different edaphoclimatic conditions. The experiments were performed in field conditions in Erechim, Caxias do Sul, Pelotas, São Francisco de Paula, and Santa Vitoria do Palmar. The experimental design was completely randomized, with nine populations, eight plants per plot and four repetitions. The following were evaluated: biomass production and essential oil chemical composition and yield. The data underwent ANOVA, followed by Tukey's multiple range test. The adaptability and stability of the populations in the different environments were also evaluated by regression analysis. The results showed great differences between the populations and cultivation sites, with genotype vs. environment interaction. Most populations presented the best biomass production results at Erechim. Pelotas and Santa Vitória do Palmar were the worst locations for poejo production, mainly due to a water deficit occurred during the experiment. The Santa Lucia population presented broad stability and the greatest adaptability to the environments for biomass and essential oil production, but its average production was not satisfactory. The André da Rocha population presented the highest average production of essential oil, and was favored in favorable environments. Regarding essential oil chemical composition, the populations kept stable contents of the major compounds at all locations, with a few variations. In some populations, a higher concentration of sesquiterpenes was observed, which can be attributed to environmental stress.


Asunto(s)
Aceites de Plantas/química , Aceites Volátiles/química , Biomasa , Lamiaceae/genética , Sesquiterpenos , Suelo/química , Clima Tropical , Análisis de Regresión , Análisis de Varianza , Genotipo
8.
Anticancer Res ; 38(11): 6231-6236, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30396942

RESUMEN

BACKGROUND/AIM: Colorectal cancer is a common type of cancer with reported resistance to treatment, in most cases due to loss of function of apoptotic and cell-cycle proteins. Piperlongumine (PPLGM) is a natural alkaloid isolated from Piper species, with promising anti-cancer properties. This study investigated whether PPLGM is able to induce cell death in colorectal carcinoma HCT 116 cells expressing wild-type or deficient in Bax, p21 or p53. MATERIALS AND METHODS: PPLGM was extracted from roots of Piper tuberculatum. Cell viability was determined by reduction of 3-(4,5-dimethilthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and clonogenic assay. Cell death was evaluated by acridine orange/ethidium bromide staining and flow cytometry. Plasmid cleavage activity and circular dichroism DNA interaction were also analyzed. RESULTS: PPLGM induced selective cell death in all cell lines (IC50 range from 10.7 to 13.9 µM) with an increase in the number of late apoptotic cells and different profiles in cell-cycle distribution. Plasmid DNA analysis showed that PPLGM does not interact directly with DNA. CONCLUSION: This paper suggests that PPLGM may be a promising candidate in colorectal cancer therapy.


Asunto(s)
Neoplasias Colorrectales/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Dioxolanos/farmacología , Proteína p53 Supresora de Tumor/genética , Proteína X Asociada a bcl-2/genética , Apoptosis , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Ensayos de Selección de Medicamentos Antitumorales , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Humanos
9.
Int J Med Mushrooms ; 20(1): 31-46, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29604911

RESUMEN

Cumulative evidence from research studies has shown that the shiitake culinary-medicinal mushroom, Lentinus edodes, is an excellent source of natural antitumor agents and is capable of inhibiting cancer cell growth. However, the cell signaling pathway that leads tumor cells to apoptosis is not well understood because many chemical compounds may be acting. This study investigated the chemopreventive effects of an L. edodes aqueous extract on human HEp-2 epithelial larynx carcinoma cells and normal human MRC-5 lung fibroblasts by identifying proliferative and apoptotic pathways. The chemical characterization of the dry powder was assessed by high-performance liquid chromatography. Antiproliferative and proapoptotic effects induced by the extract were evaluated by assessing proliferative markers, cell sorting through flow cytometry, and expression levels of apoptotic proteins with Western blotting. The results suggest that inhibition of cell proliferation was more prominent in HEp-2 than in MRC-5 cells. Cell death analysis showed the appearance of cell populations in the sub-G1 phase, with late apoptotic signal increased in a dose-dependent manner. In addition, the aqueous extract induced depolarization of mitochondria, activating the generation of intracellular reactive oxygen species in HEp-2 cells. These observations suggest that L. edodes extract may exert a chemopreventive effect, regulating mitotic induction of apoptogenic signals. These findings highlight the mushroom's pharmacological potential in cancer treatment.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Hongos Shiitake/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ácido Gálico/análisis , Humanos , Concentración 50 Inhibidora , Laringe/citología , Laringe/patología , Lentinano/farmacología , Potencial de la Membrana Mitocondrial/fisiología , Mitocondrias/efectos de los fármacos , Mitosis/efectos de los fármacos , Fenoles/análisis , Fenoles/química , Especies Reactivas de Oxígeno/metabolismo , Agua/química
10.
Food Chem Toxicol ; 112: 383-392, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29337231

RESUMEN

Pleurotus sajor-caju (PSC) is an edible mushroom used in food supplements, presenting antitumor properties through induction of cell death pathways. The PSC potential against colorectal cancer was analyzed by exposing HCT116wt cells to different PSC extracts. The PSC n-hexane extract (PSC-hex) showed the highest cytotoxicity effect (IC50 value 0.05 mg/mL). The observed cytotoxicity was then associated to apoptosis-promoting and cell cycle-arrest pathways. PSC-hex was able to induce apoptosis related to breakdown of mitochondrial membrane potential and ROS generation. The absence of cytotoxicity in HTC116-p53 and HTC116-Bax cells, alongside with an increase in p53, Bax and Caspase-3 expression, and decrease in Bcl-2 expression, supports that the pro-apoptotic effect is probably induced through a p53 associated pathway. PSC-hex induced cell cycle arrest at G2/M in HCT116wt without cytotoxicity in HTC116-p21 cells. These findings suggest that a p21/p53 cell cycle regulation pathway is probably disrupted by compounds present on PSC-hex. Identification of the major components was then performed with ergosta-5,7,22-trien-3ß-ol representing 30.6% of total weight. In silico docking studies of ergosta-5,7,22-trien-3ß against Bcl-2 were performed and results show a credible interaction with the Bcl-2 hydrophobic cleft. The results show that PSC-hex can be used as supplementary food for adjuvant therapy in colorectal carcinoma.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Colorrectales/terapia , Suplementos Dietéticos , Pleurotus/química , Antineoplásicos/aislamiento & purificación , Caspasa 3/metabolismo , División Celular/efectos de los fármacos , Línea Celular , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Ergosterol/análogos & derivados , Ergosterol/aislamiento & purificación , Ergosterol/farmacología , Fase G2/efectos de los fármacos , Células HCT116 , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Concentración 50 Inhibidora , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Simulación del Acoplamiento Molecular , Proteínas Proto-Oncogénicas c-bcl-2/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
11.
Biomed Pharmacother ; 91: 951-963, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28514834

RESUMEN

Continuous increases in the rates of tumor diseases have highlighted the need for identification of novel and inexpensive antitumor agents from natural sources. In this study, we investigated the effects of enriched fraction from hydroalcoholic Brazilian red propolis extract against Hep-2 cancer cell line. Initially 201 fractions were arranged in 12 groups according to their chromatographic characteristics (A-L). After an in vitro cell viability screening, J and L were further selected as promising enriched fractions for this study. The chemical characterization was performed and Biochanin A, Formononetin, and Liquiritigenin compounds were quantified. Through MTT viability assay and morphological changes observed by Giemsa and DAPI staining, the results showed that red propolis inhibited cancer cells growth. Flow cytometry results indicated effects that were partly mediated through programmed cell death as confirmed by externalization of phosphatidylserine, DNA cleaved assay, increase at SUB G1-G0 phase in cell cycle analysis and loss of mitochondrial membrane potential. In conclusion, our results demonstrated that red propolis enriched fractions promoted apoptotic effects in human cancer cells through the mechanisms involving mitochondrial perturbation. Therefore, red propolis fractions contain candidate agents for adjuvant cancer treatment, which further studies should elucidate the comprehensive mechanistic pathways.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias/tratamiento farmacológico , Própolis/farmacología , Apoptosis/efectos de los fármacos , Brasil , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Flavanonas/farmacología , Fase G1/efectos de los fármacos , Genisteína/farmacología , Humanos , Isoflavonas/farmacología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Fase de Descanso del Ciclo Celular/efectos de los fármacos
12.
Coluna/Columna ; 16(1): 42-47, Jan.-Mar. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-840147

RESUMEN

ABSTRACT Objective: To define histological scores for intervertebral disc degeneration that would enable the definition of morphological characteristics of disease, besides improving knowledge of the lumbar degenerative disc disease by means of immunohistochemical markers. Methods: Hematoxylin and Eosin, Alcian/PAS, Masson Trichrome and Safranin O/FCF staining was used on the intervertebral disc degeneration sections of patients with lumbar degenerative disc disease. The protein markers defined in immunohistochemistry were cell proliferation (Ki-67) and apoptosis (p53). Results: The study data enabled the determination of Safranin O/FCF stain as the most effective one for evaluating parameters such as area, diameter, and number of chondrocyte clusters. The importance of using stains in association, such as Safranin O/FCF, Masson Trichrome, Alcian/PAS and Hematoxylin and Eosin, was also determined, as they are complementary for the histopathological verification of intervertebral disc degeneration. By expressing proteins using the immunohistochemistry technique, it was possible to consider two stages of disc degeneration: cell proliferation with chondrocyte cluster formation, and induction of apoptosis. Conclusion: This study enabled the histological and immunohistochemical characterization to be determined for lumbar degenerative disc disease, and its degrees of evolution, by determining new disc degeneration scores.


RESUMO Objetivo: Definir escores histológicos de degeneração do disco intervertebral que permitam a identificação de características morfológicas da doença, além de melhorar o conhecimento sobre a discopatia degenerativa lombar por meio de marcadores imuno-histoquímicos. Métodos: As colorações histológicas de hematoxilina e eosina, azul de alcian/PAS, tricrômica de Masson e safranina O/FCF foram utilizadas em cortes de disco intervertebral degenerado de pacientes com discopatia degenerativa lombar. Os marcadores proteicos definidos na imuno-histoquímica permitiram a avaliação da proliferação celular (Ki-67) e da apoptose (p53). Resultados: Os dados do estudo permitiram a determinação da coloração de safranina O/FCF como a mais eficaz para avaliar os parâmetros tais como a área, o diâmetro e o número de agrupamentos de condrócitos. Também se determinou a importância do uso das colorações histológicas de forma associada, como safranina O/FCF, tricrômica de Masson, azul de alcian/PAS e hematoxilina e eosina, uma vez que elas são complementares para a verificação histopatológica da degeneração do disco intervertebral. Pela técnica da expressão de proteínas com técnica imuno-histoquímica, foi possível considerar dois estágios de degeneração do disco: proliferação de células com a formação de agrupamentos de condrócitos, seguida pela indução de apoptose. Conclusão: Este estudo permitiu definir a caracterização histológica e imuno-histoquímica em discopatia degenerativa lombar e seus graus de evolução, determinando novos escores de degeneração discal.


RESUMEN Objetivo: Definir valores histológicos de degeneración del disco intervertebral que permitan la definición de las características morfológicas de la enfermedad y mejorar el conocimiento de la enfermedad degenerativa del disco lumbar mediante marcadores inmunohistoquímicos. Métodos: Las coloraciones histológicas con hematoxilina y eosina, azul alcián/PAS, tricrómico de Masson y safranina O/FCF se utilizaron en secciones de los discos intervertebrales degenerados de pacientes con enfermedad degenerativa del disco lumbar. Los marcadores de proteínas definidos por inmunohistoquímica permitieron la evaluación de la proliferación celular (Ki-67), y la apoptosis (p53) . Resultados: Los datos de la determinación permitieron establecer la tinción con safranina O/FCF como la más eficaz para evaluar parámetros tales como el área, diámetro y número de agrupaciones de condrocitos. Se determinó también la importancia del uso asociado de diversas tinciones, como safranina O/FCF, tricrómico de Masson, azul de alcián/PAS y hematoxilina y eosina, ya que son complementarias para la verificación histopatológica de la degeneración del disco intervertebral. Por la técnica de la expresión de proteína con análisis inmunohistoquímica, fue posible establecer dos etapas de la degeneración del disco: la proliferación de células con la formación de agrupaciones de condrocitos y la inducción de la apoptosis. Conclusión: Este estudio permitió definir la caracterización histológica e inmunohistoquímica en la enfermedad degenerativa del disco lumbar y sus grados de evolución, mediante la determinación de nuevas puntuaciones de degeneración del disco.


Asunto(s)
Humanos , Disco Intervertebral , Técnicas Histológicas , Inmunohistoquímica , Degeneración del Disco Intervertebral
13.
World J Microbiol Biotechnol ; 31(5): 755-62, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25721421

RESUMEN

This study analyses the effect of the crude enzymatic extract produced by Kluyveromyces marxianus (EEB) in the maceration and clarification of juice produced from Ives (Vitis labrusca) grapes compared to the commercial enzyme preparation Pectinex(®)Ultra Color (PEC). Treatments were conducted with a total pectinolytic activity of 1 U/mL of fruit juice, at 40 °C, for 60 min. After the enzymatic treatment, the juices were evaluated with respect to yield, viscosity, and degree of clarification, as well as the effect of the enzymes on polyphenol concentration, anthocyanins, and juice color. The results showed that both EEB and PEC increase yield, reduce viscosity and contribute to the clarification of grape juice. After enzyme treatment with the EEB preparation, the extraction yield increased 28.02 % and decreased 50.70 % in viscosity during the maceration of the pulp. During the juice production process clarification increased 11.91 %. With PEC, higher values for these parameters: 42.36, 63.20, and 26.81 % respectively, were achieved. The addition of EEB resulted in grape juice with better color intensity and extraction of phenolic compounds and anthocyanins. Considering all comparison criteria, the enzymatic extract of K. marxianus NRRL-Y-7571 can potentially be used in the production of juice.


Asunto(s)
Bebidas/microbiología , Hidrolasas/aislamiento & purificación , Hidrolasas/metabolismo , Kluyveromyces/enzimología , Kluyveromyces/metabolismo , Pectinas/metabolismo , Vitis/microbiología , Temperatura
14.
World J Microbiol Biotechnol ; 30(5): 1541-7, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24347085

RESUMEN

The effect of the addition of enzymatic extract of Kluyveromyces marxianus NRRL-Y-7571 during the maceration and fermentation steps of Cabernet Sauvignon wine production was evaluated. The results obtained in the analytical determinations of the wines showed levels within the limits established by legislation and similar to values found in other studies. The results show that by adding the enzyme to the red wines these showed color characteristics considered to be superior to those of the control wine and accelerated the extraction of phenolic compounds and anthocyanins. It was observed that by using the commercial enzyme preparation there was an increase of 15 % in polyphenol content compared to the control wine and an increase of 28 % when the crude enzyme extract was used. Anthocyanin content in the wine increased after treatment with the commercial enzyme preparation (10 %) and with the use of the crude enzymatic extract (22 %). Considering all comparison criteria, the K. marxianus enzymatic extract showed results statistically similar or superior to those obtained with the commercial enzyme preparation.


Asunto(s)
Antocianinas/análisis , Kluyveromyces/aislamiento & purificación , Poligalacturonasa/metabolismo , Polifenoles/análisis , Vino/análisis , Fermentación , Manipulación de Alimentos/métodos , Proteínas Fúngicas/metabolismo , Kluyveromyces/clasificación , Kluyveromyces/enzimología , Vino/microbiología
15.
Braz. arch. biol. technol ; Braz. arch. biol. technol;55(1): 1-6, Jan.-Feb. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-622675

RESUMEN

Acanthamoeba are abundant in a wide range of environments, and some species are responsible for cutaneous infections, keratitis, and granulomatous amoebic encephalitis (GAE). The conventional detection and isolation of amoeba from clinical and environmental samples involves sampling and culture on non-nutrient Ágar medium. Although efficient, this system requires several transfers in order to eliminate contaminants, and is not appropriate for the isolation of individual amoeba from samples with a biodiverse community. In this study we propose an alternative method for the isolation of monocystic clones of Acanthamoeba. The propose method involves sampling, enrichment, encystment induction, and direct cysts micromanipulation and culture on Ágar plates.

16.
Braz. j. infect. dis ; Braz. j. infect. dis;15(2): 138-143, Mar.-Apr. 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-582416

RESUMEN

OBJECTIVES: To determine the prevalence of class A extended spectrum β-lactamases (ESBL)-producing Escherichia coli and Klebsiella spp., and to investigate clonality among ESBL-producing isolates of nosocomial and community infections. METHODS: The study involved 354 nosocomial infections samples and 992 community infections samples, obtained between 2003 and 2006 at Caxias do Sul, RS. The detection of ESBL was performed by the disk-diffusion test. Presence of blaCTX-M, blaSHV and blaTEM β-lactamase genes was evaluated by PCR, and genomic typing was determined by pulsed-field gel electrophoresis analysis. RESULTS: Higher frequency of ESBL-producing isolates were detected among nosocomial samples of E. coli (6.7 percent) and Klebsiella (43.7 percent), than those obtained from community infections (0.4 percent and 2.6 percent). blaTEM and blaCTX were the most prevalent ESBL gene families in both E. coli and Klebsiella isolates. Different pulsotypes were obtained among ESBL-producing E. coli and 11 clones for Klebsiella spp., which occurred over the years and in different hospital wards. Among ESBL-producing K. pneumoniae, 74.3 percent transferred ESBL genes by conjugation and exhibited concomitant decreased aminoglycosides susceptibility. CONCLUSION: ESBL-producing E. coli, and especially K. pneumoniae are essentially a nosocomial problem, and their dissemination to the community is relatively limited. The great genetic variability observed among ESBL-producing bacteria indicates polyclonal spread and high transference of ESBL genes between bacteria in the hospital environment. This information is of paramount importance for nosocomial infection control.


Asunto(s)
Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infección Hospitalaria/microbiología , Infecciones por Escherichia coli/microbiología , Escherichia coli/enzimología , Infecciones por Klebsiella/microbiología , Klebsiella/enzimología , beta-Lactamasas/biosíntesis , Antibacterianos/farmacología , Brasil/epidemiología , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Pruebas Antimicrobianas de Difusión por Disco , ADN Bacteriano/análisis , Electroforesis en Gel de Campo Pulsado , Infecciones por Escherichia coli/epidemiología , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Infecciones por Klebsiella/epidemiología , Klebsiella/efectos de los fármacos , Klebsiella/aislamiento & purificación , Prevalencia
17.
Genet. mol. biol ; Genet. mol. biol;34(2): 353-360, 2011. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-587768

RESUMEN

Promoters are DNA sequences located upstream of the gene region and play a central role in gene expression. Computational techniques show good accuracy in gene prediction but are less successful in predicting promoters, primarily because of the high number of false positives that reflect characteristics of the promoter sequences. Many machine learning methods have been used to address this issue. Neural Networks (NN) have been successfully used in this field because of their ability to recognize imprecise and incomplete patterns characteristic of promoter sequences. In this paper, NN was used to predict and recognize promoter sequences in two data sets: (i) one based on nucleotide sequence information and (ii) another based on stability sequence information. The accuracy was approximately 80 percent for simulation (i) and 68 percent for simulation (ii). In the rules extracted, biological consensus motifs were important parts of the NN learning process in both simulations.

18.
Braz. arch. biol. technol ; Braz. arch. biol. technol;53(4): 883-888, July-Aug. 2010. graf, tab
Artículo en Inglés | LILACS | ID: lil-554783

RESUMEN

Nodal segments from greenhouse grown adult plants of Salvia guaranitica were used to evaluate the effect of culture media and growth regulators on the micropropagation and growth. The highest multiplication rate was obtained on Murashige and Skoog (MS) medium supplemented with 2.22 µM of 6-benzylaminopurine (BAP). The best condition for rooting was MS medium with 2.85 µM indole-3-acetic acid (IAA). Rooted plants were successfully acclimatized and exhibited a normal development until maturity. Using the described protocol, approximately 35 plants per explant were obtained after three months.


Segmentos nodais de plantas adultas de Salvia guaranitica cultivadas em estufa, foram utilizados para avaliar o efeito do meio de cultivo e reguladores de crescimento na micropropagação. A maior taxa de multiplicação foi obtida em meio Murashige and Skoog (MS) suplementado com 2.22 µM de 6-benzilaminopurina (BAP). A melhor condição para enraizamento foi o meio MS acrescido de 2.85 µM de ácido indol-3-acético (IAA). Plântulas enraizadas foram aclimatizadas com sucesso e exibiram desenvolvimento normal até a fase adulta. Utilizando o protocolo descrito, aproximadamente 35 plantas por explante foram obtidas após 3 meses.

19.
Electron. j. biotechnol ; Electron. j. biotechnol;13(2): 2-3, Mar. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-567080

RESUMEN

The purpose of this work was to study the biodegradation of citronellol, citronellal and citronellyl acetate by a soil Pseudomonas mendocina strain (IBPse 105) isolated from a Cymbopogon windelandi field. This strain efficiently used citronellol, citronellal, citronellyl acetate and myrcene as sole source of carbon, but was not able to grow on other 15 monoterpenoids evaluated. Gas chromatography-mass spectrometry (GC-MS) analysis of metabolites accumulation during P. medocina IBPse 105 growth on citronellol showed that this strain uses the citronellol catabolic pathway described for other species of the genus. IBPse 105 degradation of citronellyl acetate initiates by its hydrolysis to citronellol. The mini-Tn5 insertion in mutant IBPse 105-303, impaired in citronellol degradation, but able to grow on citronellal, was located in a homologous of the P. aeruginosa atuB gene, that codifies citronellol deshydrogenase.


Asunto(s)
Monoterpenos/metabolismo , Pseudomonas mendocina/metabolismo , Biotransformación , Cromatografía de Gases y Espectrometría de Masas , Hidrólisis , Mutagénesis , Pseudomonas mendocina/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
Acta sci., Biol. sci ; Acta sci., Biol. sci;32(1): 39-42, jan.-mar.2010. ilus, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1460633

RESUMEN

A progeny of Cambona-4, a female maté plant (Ilex paraguariensis) selected by its agronomical characteristics and mild flavor, was evaluated using RAPD markers in order to identify its male parents. Using RAPD markers specifics of each one of the four potential males, the paternity of 84 out of 107 offsprings was confirmed. The majority of the offsprings (83.3%) were ascribed to pollen donor A, while male plants B, C, and D represented 11.9, 4.8, and 0%, respectively. The highly desirable agronomical characteristics and product quality of Cambona-4/pollen donor A offsprings, identified by RAPD markers, lead to the planting of an orchard Cambona-4 and pollinator A to obtain bi-clonal commercial seeds


Uma progênie da matriz feminina de erva-mate (Ilex paraguariensis) denominada Cambona-4, selecionada pelas suas características agronômicas e sabor suave, foi avaliada por marcadores RAPD para a identificação dos respectivos parentais masculinos. Usando-se fragmentos específicos de RAPD de cada um dos quatro polinizadores potenciais, a paternidade de 84 de 107 descendentes foi confirmada. A maioria dos descendentes (83,3%) foi atribuída ao polinizador A, enquanto os polinizadores B, C e D representaram 11,9; 4,8 e 0%, respectivamente. As características agronômicas e de qualidade do produto, oriundas da progênie Cambona-4/polinizador A, identificado pelos marcadores RAPD, direcionaram o plantio de um pomar a partir do cruzamento destas para obtenção de sementes comerciais biclonais.


Asunto(s)
Ilex paraguariensis , Polinización
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