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1.
J Food Sci Technol ; 53(1): 281-92, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26787948

RESUMEN

Pomegranate extract, vanillin and geraniol were studied as natural antimicrobials on strawberry juice. Strawberry juice was treated with each agent at two concentrations: pomegranate extract at 180 and 360 µg/mL; vanillin at 2.5 and 5 mg/mL; and geraniol at 0.6 and 1.2 µL/mL. After being treated, juices were stored at 5 °C and microbiological, physicochemical and sensory studies were carried out. Also, a second batch of juice was inoculated with Escherichia coli O157:H7 (10(5) CFU/mL) before being treated, to safety study. Geraniol and vanillin, at both concentrations tested, were highly effective in reducing the native microflora on strawberry juice (more than 3 log cycles), extending the microbiological shelf-life of the product. Moreover, both antimicrobials improved the product safety by reducing inoculated E. coli O157:H7. Furthermore, vanillin showed a significant increase in polyphenol content compared to untreated juice. On the other hand, pomegranate extract applied at the highest concentration showed important reductions on mesophilic and psychrophilic bacteria, but no effect on yeast and molds and inoculated E. coli. Even though vanillin and geraniol incorporation on strawberry juice had a negative effect on its sensory quality, pomegranate extract had no impact on the sensory attributes evaluated. Combinations of the biopreservatives could be studied in order to decrease the concentration of the antimicrobials, reducing the effects on strawberry juice sensory characteristics.

2.
Carbohydr Polym ; 92(1): 817-23, 2013 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-23218371

RESUMEN

Many studies have focused on seed decontamination but no one has been capable of eliminating all pathogenic bacteria. Two objectives were followed. First, to assess the in vitro antimicrobial activity of chitosan against: (a) Escherichia coli O157:H7, (b) native microflora of lettuce and (c) native microflora of lettuce seeds. Second, to evaluate the efficiency of chitosan on reducing microflora on lettuce seeds. The overall goal was to find a combination of contact time and chitosan concentration that reduces the microflora of lettuce seeds, without affecting germination. After treatment lettuce seeds presented no detectable microbial counts (<10(2)CFU/50 seeds) for all populations. Moreover, chitosan eliminated E. coli. Regardless of the reduction in the microbial load, a 90% reduction on germination makes imbibition with chitosan, uneconomical. Subsequent treatments identified the optimal treatment as 10 min contact with a 10 g/L chitosan solution, which maintained the highest germination percentage.


Asunto(s)
Quitosano/farmacología , Conservantes de Alimentos/farmacología , Lactuca , Semillas , Quitosano/química , Escherichia coli O157/efectos de los fármacos , Microbiología de Alimentos , Germinación/efectos de los fármacos , Lactuca/efectos de los fármacos , Lactuca/crecimiento & desarrollo , Lactuca/microbiología , Medicago sativa/microbiología , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Semillas/microbiología
3.
Arq. Inst. Biol ; 80(1): 125-128, jan.-mar.2013.
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1462203

RESUMEN

Resíduos do inseticida e nematicida carbofurano e de seu principal metabólito 3-hidroxicarbofurano foram averiguados em tabuleiros de arroz irrigado e em áreas adjacentes para controle do gorgulho aquático da espécie Oryzophagus oryzae Lima, 1936. As amostras foram coletadas no período de 6/9/1999 a 4/5/2000 e analisadas por cromatografia a líquido de alta eficiência (HPLC) utilizando-se detector de fluorescência. Não foram detectados resíduos de carbofurano e de seu metabólito 3-hidroxicarbofurano dentro dos limites de determinação do método.


The presence of residues of the insecticide and nematicide carbofuran, used for weevil (Oryzophagus oryzae Lima 1936) control, and its principal metabolite 3-hydroxycarbofuran were evaluated in soil and sediment plots from paddy rice fields and adjacent areas. The samples were analyzed using a high-performance liquid chromatography and fluorescence detector. Carbofuran and 3-hydroxycarbofuran residues were not detected in any sample in amounts above the method’s detection threshold.


Asunto(s)
Análisis del Suelo , Cromatografía de Gases y Espectrometría de Masas/veterinaria , Insecticidas/análisis , Insecticidas/toxicidad , Gorgojos/clasificación , Oryza
4.
J Food Sci ; 73(6): M257-63, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19241554

RESUMEN

The native microflora of lettuce cultivated in mulch and on bare soil and its evolution during storage at optimal condition were evaluated. Inner, mid, and outer leaves of the lettuce heads were analyzed separately and the evolution of the microbial populations were fitted to Gompertz and logistic models. The cultivation method (bare soil and mulch) introduced differences in the initial counts, evolution, and tolerance to refrigeration temperatures for some of the microbial populations under study. Most microbial populations from mulch lettuce presented a decline or little growth under refrigerated storage. However, populations from bare soil lettuce presented some growth phase during storage. Lactic acid bacteria from bare soil lettuce presented significant growth after 8 d of storage while LAB from mulch grown lettuce did not. Concurrently with the LAB growth, there was a decline in the coliform counts in bare soil grown lettuce. At the end of storage, the inner and mid leaves of mulch lettuce presented lower counts of psychrotrophic bacteria, LAB, and yeast and molds.


Asunto(s)
Agricultura/métodos , Bacterias/crecimiento & desarrollo , Conservación de Alimentos/métodos , Lactuca/microbiología , Microbiología del Suelo , Bacterias/aislamiento & purificación , Recuento de Colonia Microbiana , Seguridad de Productos para el Consumidor , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Humanos , Lactuca/crecimiento & desarrollo , Lactuca/normas , Modelos Logísticos , Dinámica Poblacional , Factores de Tiempo
5.
Mem Inst Oswaldo Cruz ; 100(4): 371-6, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16113884

RESUMEN

The present work evaluated the epidemiology of human immunodeficiency virus 1/human T-cell lymphotropic virus (HIV-1/HTLV) coinfection in patients living in Belém (state of Pará) and Macapá (state of Amapá), two cities located in the Amazon region of Brazil. A total of 169 blood samples were collected. The sera were tested by enzyme-linked immunosorbent assay to determine the presence of antibodies anti-HTLV-1/2. Confirmation of infection and discrimination of HTLV types and subtypes was performed using a nested polymerase chain reaction targeting the pX and 5' LTR regions, followed by restriction fragment length polymorphism and sequencing analysis. The presence of anti-HTLV1/2 was detected in six patients from Belém. The amplification of the pX region followed by RFLP analysis, demonstrated the presence of HTLV-1 and HTLV-2 infections among two and four patients, respectively. Sequencing HTLV-1 5' LTR indicated that the virus is a member of the Cosmopolitan Group, Transcontinental subgroup. HTLV-2 strains isolated revealed a molecular profile of subtype HTLV-2c. These results are a reflex of the epidemiological features of HIV-1/HTLV-1/2 coinfection in the North region of Brazil, which is distinct from other Brazilian regions, as reported by previous studies.


Asunto(s)
Infecciones por VIH/complicaciones , VIH-1 , Infecciones por HTLV-I/epidemiología , Infecciones por HTLV-II/epidemiología , Virus Linfotrópico T Tipo 1 Humano/genética , Virus Linfotrópico T Tipo 2 Humano/genética , Brasil/epidemiología , Femenino , Infecciones por HTLV-I/virología , Infecciones por HTLV-II/virología , Humanos , Masculino , Filogenia , Prevalencia
6.
Mem. Inst. Oswaldo Cruz ; 100(4): 371-376, July 2005. ilus, tab
Artículo en Inglés | LILACS | ID: lil-405991

RESUMEN

The present work evaluated the epidemiology of human immunodeficiency virus 1/human T-cell lymphotropic virus (HIV-1/HTLV) coinfection in patients living in Belém (state of Pará) and Macapá (state of Amapá), two cities located in the Amazon region of Brazil. A total of 169 blood samples were collected. The sera were tested by enzyme-linked immunosorbent assay to determine the presence of antibodies anti-HTLV-1/2. Confirmation of infection and discrimination of HTLV types and subtypes was performed using a nested polymerase chain reaction targeting the pX and 5' LTR regions, followed by restriction fragment length polymorphism and sequencing analysis. The presence of anti-HTLV1/2 was detected in six patients from Belém. The amplification of the pX region followed by RFLP analysis, demonstrated the presence of HTLV-1 and HTLV-2 infections among two and four patients, respectively. Sequencing HTLV-1 5' LTR indicated that the virus is a member of the Cosmopolitan Group, Transcontinental subgroup. HTLV-2 strains isolated revealed a molecular profile of subtype HTLV-2c. These results are a reflex of the epidemiological features of HIV-1/HTLV-1/2 coinfection in the North region of Brazil, which is distinct from other Brazilian regions, as reported by previous studies.


Asunto(s)
Humanos , Masculino , Femenino , Infecciones por VIH/complicaciones , VIH-1 , Infecciones por HTLV-I/epidemiología , Infecciones por HTLV-II/epidemiología , Virus Linfotrópico T Tipo 1 Humano/genética , /genética , Donantes de Sangre , Brasil/epidemiología , Ensayo de Inmunoadsorción Enzimática , Anticuerpos Anti-HTLV-I/sangre , Infecciones por HTLV-I/complicaciones , Infecciones por HTLV-I/virología , Anticuerpos Anti-HTLV-II/sangre , Infecciones por HTLV-II/complicaciones , Infecciones por HTLV-II/virología , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia
7.
Phytomedicine ; 11(6): 549-53, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15500268

RESUMEN

Alpinia zerumbet, known popularly as "colônia" in Northeastern Brazil, is a medicinal plant that has been used widely in folk medicine as teas and infusions for the treatment of intestinal and cardiovascular diseases, including arterial hypertension. Our previous studies have demonstrated that the essential oil of A. zerumbet (OEAZ) is very active on excitable tissues, such as smooth muscle, and in this study we verified its effects on the compound action potential (CAP) of rat sciatic nerve. EOAZ induced a dose-dependent blockade of the CAP. Control peak-to-peak amplitude and conduction velocity of CAPs were 7.6 +/- 0.43 mV and 80.6 +/- 3.19 m/s, respectively. At 60 microg/ml, EOAZ induced no demonstrable effect. Conduction velocity was significantly reduced at 180 min of preparation exposure to 100 microg/ml of EOAZ. At 300, 600 and 2000 microg/ml doses of EOAZ, the peak-to-peak amplitudes of CAPs following 180 min exposure of the nerve to the drug were reduced significantly, to 75.3 +/- 7.36%, 50.45 +/- 2.17% and 0% respectively, of control value. Conduction velocity was reduced significantly by 300, 600 and 2000 microg/ml of EOAZ, at 180 min, to 83.61 +/- 3.28%, 64.06 +/- 8.21% and 22.7 +/- 5.79%, respectively, of control value. All these effects developed slowly and were reversible upon a 180-min wash.


Asunto(s)
Alpinia , Fitoterapia , Aceites de Plantas/farmacología , Nervio Ciático/efectos de los fármacos , Potenciales de Acción/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Masculino , Hojas de la Planta , Aceites de Plantas/administración & dosificación , Aceites de Plantas/uso terapéutico , Ratas , Ratas Wistar
8.
Braz J Med Biol Res ; 34(10): 1337-40, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11593310

RESUMEN

Terpineol, a volatile terpenoid alcohol of low toxicity, is widely used in the perfumery industry. It is an important chemical constituent of the essential oil of many plants with widespread applications in folk medicine and in aromatherapy. The effects of terpineol on the compound action potential (CAP) of rat sciatic nerve were studied. Terpineol induced a dose-dependent blockade of the CAP. At 100 microM, terpineol had no demonstrable effect. At 300 microM terpineol, peak-to-peak amplitude and conduction velocity of CAP were significantly reduced at the end of 180-min exposure of the nerve to the drug, from 3.28 +/- 0.22 mV and 33.5 +/- 7.05 m/s, respectively, to 1.91 +/- 0.51 mV and 26.2 +/- 4.55 m/s. At 600 microM, terpineol significantly reduced peak-to-peak amplitude and conduction velocity from 2.97 +/- 0.55 mV and 32.8 +/- 3.91 m/s to 0.24 +/- 0.23 mV and 2.72 +/- 2.72 m/s, respectively (N = 5). All these effects developed slowly and were reversible upon 180-min washout.


Asunto(s)
Potenciales de Acción/efectos de los fármacos , Monoterpenos , Nervio Ciático/efectos de los fármacos , Terpenos/farmacología , Animales , Monoterpenos Ciclohexánicos , Ciclohexenos , Conducción Nerviosa/efectos de los fármacos , Aceites Volátiles/química , Ratas , Ratas Wistar , Nervio Ciático/fisiología
9.
Braz. j. med. biol. res ; 34(10): 1337-1340, Oct. 2001. tab, graf
Artículo en Inglés | LILACS | ID: lil-299836

RESUMEN

Terpineol, a volatile terpenoid alcohol of low toxicity, is widely used in the perfumery industry. It is an important chemical constituent of the essential oil of many plants with widespread applications in folk medicine and in aromatherapy. The effects of terpineol on the compound action potential (CAP) of rat sciatic nerve were studied. Terpineol induced a dose-dependent blockade of the CAP. At 100 æM, terpineol had no demonstrable effect. At 300 æM terpineol, peak-to-peak amplitude and conduction velocity of CAP were significantly reduced at the end of 180-min exposure of the nerve to the drug, from 3.28 + or - 0.22 mV and 33.5 + or - 7.05 m/s, respectively, to 1.91 + or - 0.51 mV and 26.2 + or - 4.55 m/s. At 600 æM, terpineol significantly reduced peak-to-peak amplitude and conduction velocity from 2.97 + or - 0.55 mV and 32.8 + or - 3.91 m/s to 0.24 + or - 0.23 mV and 2.72 + or - 2.72 m/s, respectively (N = 5). All these effects developed slowly and were reversible upon 180-min washout


Asunto(s)
Animales , Ratas , Potenciales de Acción , Nervio Ciático , Terpenos , Conducción Nerviosa , Aceites Volátiles , Ratas Wistar , Nervio Ciático
10.
Rev Panam Salud Publica ; 3(5): 308-13, 1998 May.
Artículo en Portugués | MEDLINE | ID: mdl-9643074

RESUMEN

In 1995, cervical cancer was the fourth most important cause of death among women in the state of Rio Grande do Sul, Brazil. There are no available studies on Pap smear examination coverage in Pelotas, which is the largest city in the southern part of Rio Grande do Sul. Accordingly, in 1992 a population-based, cross-sectional study was carried out among 20 to 69 year-old women residing in urban areas of the city. The objectives of the study were to ascertain any Pap smear testing in the 3 years prior to the study, to determine the coverage of cervical cancer screening, and to identify any factors associated with the performance of Pap tests in Pelotas. Social class was chosen as the determining variable. To categorize social class, two classifications were used: Bronfman's classification and the classification used by the Brazilian Association of Market Research Institutes. Among the 934 women interviewed, 606 (65%) had had a Pap smear test in the 3 years before the study. The multivariate analysis revealed significant differences regarding performance of such tests in terms of social class, age, and frequency of medical consultations per year. No significant differences were found in terms of education, type of health service used, or hospitalizations during the year prior to the study. This study reveals that coverage of cervical cancer screening for women between 20 and 69 years of age in Pelotas is higher than the coverage found in other parts of the country or even of the world. However, for women in lower social classes, coverage was found to be between 52 and 56%. These data can contribute to the development of measures aimed at increasing cervical cancer screening among specific sectors of the population.


Asunto(s)
Prueba de Papanicolaou , Frotis Vaginal , Adulto , Anciano , Brasil , Femenino , Humanos , Persona de Mediana Edad , Oportunidad Relativa , Clase Social , Neoplasias del Cuello Uterino/prevención & control
11.
J. bras. urol ; 8(2): 79-81, 1982.
Artículo en Portugués | LILACS | ID: lil-8421

RESUMEN

Os autores realizaram 16 urografias em pacientes portadores de insufiencia renal aguda e cronica, com altas doses de contraste iodado, obtendo imagens radiograficas diagnosticas, sem no entanto, evidenciarem alteracoes na funcao renal, baseado na dosasgem sanguinea de creatinina pre e pos exame radiologico. Tambem nao foram notados efeitos colaterais do tipo hipersensibilidade


Asunto(s)
Adulto , Persona de Mediana Edad , Humanos , Masculino , Femenino , Lesión Renal Aguda , Pruebas de Función Renal , Insuficiencia Renal Crónica , Urografía
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