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1.
Crit Rev Food Sci Nutr ; 57(1): 48-58, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-26048727

RESUMO

Lipid is the general name given to fats and oils, which are the basic components of cooking oils, shortening, ghee, margarine, and other edible fats. The chosen term depends on the physical state at ambient temperature; fats are solids and oils are liquids. The chemical properties of the lipids, including degree of saturation, fatty acid chain length, and acylglycerol molecule composition are the basic determinants of physical characteristics such as melting point, cloud point, solid fat content, and thermal behavior. This review will discuss the major lipid modification strategies, hydrogenation, and chemical and enzymatic interesterification, describing the catalysts used mechanisms, kinetics, and impacts on the health-related properties of the final products. Enzymatic interesterification will be emphasized as method that produces a final product with good taste, zero trans fatty acids, and a low number of calories, requires less contact with chemicals, and is cost efficient.


Assuntos
Gorduras na Dieta/análise , Gorduras/química , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos , Tecnologia de Alimentos , Saúde Global , Ácidos Graxos trans/efeitos adversos , Animais , Fenômenos Químicos , Comportamento do Consumidor , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Esterificação , Qualidade dos Alimentos , Tecnologia de Alimentos/tendências , Humanos , Hidrogenação , Lipase/química , Lipase/metabolismo , Estrutura Molecular , Estereoisomerismo , Ácidos Graxos trans/análise , Ácidos Graxos trans/química , Ácidos Graxos trans/metabolismo
2.
Braz. j. microbiol ; 39(4): 787-791, Dec. 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-504323

RESUMO

Samples of food crops (peanut, peeled pistachio, unpeeled pistachio, rice, and corn) and feed (barley, bran, corn) were autoclave-sterilized, and inoculated with 10(6) of spore suspension of an isolate of Aspergillus flavus fungus known to produce aflatoxin B1 (AFB1) . Following a 10-day period of incubation at 27 C to allow for fungal growth, food and feed samples were irradiated with gamma radiation at the doses 4, 6, and 10 kGy. Results indicated that degradation of AFB1 was positively correlated with the increase in the applied dose of gamma ray for each tested sample. At a dose of 10 kGy percentages of AFB1 degradation reached highest values at 58.6, 68.8, 84.6, 81.1 and 87.8 percent for peanuts, peeled pistachios, unpeeled pistachios, corn and rice samples, respectively. In feed samples percentages of AFB1 degradation were 45, 66, and 90 percent in barley, 47, 75, and 86 percent in bran, and 31, 72, and 84 percent in corn for the doses of 4, 6, and 10 kGy, respectively. AFB1 degradation in food samples correlated negatively with oil content in irradiated samples. Thus, in peanuts, which contained the highest oil content, percentage of AFB1 degradation at 10 kGy was not more than 56.6 percent, whereas, the corresponding value in corn, which contained the lowest oil content, reached as high as 80 percent. The above results indicate the possibility of using gamma radiation as a means of degradation of AFB1 in food and feed crops to levels lower than the maximum allowed levels.


Amostras de alimentos (amendoim, pistache descascada, pistache com casca, arroz e milho) e de ração (cevada, farelo de trigo e milho) foram esterilizadas por autoclavação e inoculadas com uma suspensão de esporos (10(6)) de um isolado de Aspergillus flavus produtor de aflatoxina B1 (AFB1). Após incubação por 10 dias a 27ºC para multiplicação do fungo, as amostras foram irradiadas com radiação gama nas doses de 4, 6 e 10 kGy. Os resultados indicaram que a degradação da AFB1 correlacionou-se positivamente com o aumento da dose de radiação gama. As porcentagens de degradação da AFB1 foram mais altas na dose de 10kGy, obtendo-se valores de 58,6, 68,8, 84,6, 81,1 e 87,8 por cento para amendoim, pistache descascada, pistache com casca, milho e arroz, respectivamente. Nas rações, as porcentagens de degradação de AFB1 foram 45, 66 e 90 por cento para cevada, 47, 75 e 86 por cento para farelo de trigo e 31, 72 e 84 por cento para milho, nas doses de 4, 6 e 10 kGy, respectivamente. A degradação de AFB1 correlacionou-se negativamente com o teor de gordura nas amostras irradiadas. Assim, em amendoim, que apresentou o teor de gordura mais alto, a porcentagem de degradação com 10 kGy foi inferior a 56,6 por cento, enquanto o valor correspondente em milho, que apresentou o teor de gordura mais baixo, foi de 80 por cento. Os resultados indicam a possibilidade de uso da radiação gama como meio de degradação de AFB1 em alimentos e ração a níveis inferiores ao máximo permitido.


Assuntos
Ração Animal , Aflatoxina B1/análise , Aspergillus flavus/crescimento & desenvolvimento , Alimentos , Inativação Gênica , Efeitos da Radiação , Esporos Fúngicos , Amostras de Alimentos , Métodos , Métodos
3.
Braz J Microbiol ; 39(4): 787-91, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24031308

RESUMO

Samples of food crops (peanut, peeled pistachio, unpeeled pistachio, rice, and corn) and feed (barley, bran, corn) were autoclave-sterilized, and inoculated with 10(6) of spore suspension of an isolate of Aspergillus flavus fungus known to produce aflatoxin B1 (AFB1) . Following a 10-day period of incubation at 27 C to allow for fungal growth, food and feed samples were irradiated with gamma radiation at the doses 4, 6, and 10 kGy. Results indicated that degradation of AFB1 was positively correlated with the increase in the applied dose of gamma ray for each tested sample. At a dose of 10 kGy percentages of AFB1 degradation reached highest values at 58.6, 68.8, 84.6, 81.1 and 87.8% for peanuts, peeled pistachios, unpeeled pistachios, corn and rice samples, respectively. In feed samples percentages of AFB1 degradation were 45, 66, and 90% in barley, 47, 75, and 86% in bran, and 31, 72, and 84% in corn for the doses of 4, 6, and 10 kGy, respectively. AFB1 degradation in food samples correlated negatively with oil content in irradiated samples. Thus, in peanuts, which contained the highest oil content, percentage of AFB1 degradation at 10 kGy was not more than 56.6%, whereas, the corresponding value in corn, which contained the lowest oil content, reached as high as 80%. The above results indicate the possibility of using gamma radiation as a means of degradation of AFB1 in food and feed crops to levels lower than the maximum allowed levels.

4.
Folia Microbiol (Praha) ; 52(4): 423-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18062192

RESUMO

A chlorpyrifos (CPY)-degrading bacterial strain was isolated from an activated sludge sample collected from the Damascus Wastewater Treatment Plant, Syria. The isolation of Klebsiella sp. was facilitated by the addition of CPY at a rate of 3.84 g/L of sludge weekly (selection pressure). Identification of Klebsiella sp. was done using major staining and biochemical differentiation tests (Gram stain, cytochrome oxidase and some relevant saccharide fermentation tests using biochemical assays). Klebsiella sp. was maintained by culturing in a poor medium consisting of mineral salts and CPY as the sole carbon source. When 3 activated sludge samples were incubated in the presence of CPY (13.9 g/L sludge), 46% of added CPY were degraded within 4 d. By comparison, within 4 d the isolated Klebsiella sp. was found to break down 92% of CPY when co-incubated in a poor mineral medium in which CPY was the sole carbon source (13.9 g/L poor medium). Isolated Klebsiella sp. was able to tolerate up to 17.3 g of CPY in the poor medium.


Assuntos
Clorpirifos/metabolismo , Klebsiella/metabolismo , Esgotos/microbiologia , Microbiologia da Água , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Síria
5.
Bioresour Technol ; 90(2): 139-43, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12895556

RESUMO

Samples of concentrated municipal sewage sludge, stored for 2, 4 and 6 months, with moisture contents of 2%, 20%, 40%, 60%, and 80% were exposed to doses of 0, 1, 2, 3, 4 and 5 kilogray (kGy) of gamma irradiation. Immediately after irradiation, total microbial count and bacterial pathogens in sewage sludge were determined. The results indicated that in all tested sewage sludge samples, bacterial pathogens including Enterobacter sp., Klebsiella sp., Salmonella sp., and Escherichia coli were initially detected. All doses of gamma irradiation reduced the total counts of microorganisms. D(10) of total count decreased with increase in the moisture content of the sewage sludge. The lowest lethal dose for tested bacterial pathogens was 5 kGy in air dried sewage sludge. In addition for wet sewage sludge having more than 40% moisture, the lethal dose was 1 kGy, for samples taken at different storage periods 2, 4 and 6 months, and therefore the cost per unit could be decreased to half when wet sewage sludge (about 50% moisture) was used.


Assuntos
Bactérias/efeitos da radiação , Descontaminação/métodos , Raios gama , Esgotos/microbiologia , Análise de Variância , Contagem de Colônia Microbiana , Água/análise
7.
Thorax ; 52(12): 1056-9, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9516899

RESUMO

BACKGROUND: Arthritis is a well recognised complication of cystic fibrosis. The cause of this arthritis is not yet clear but it is likely to be an immunological reaction to one of the many bacterial antigens to which the lungs are exposed. One such group, the heat shock proteins, (hsp), was investigated. These are immunodominant antigens of a wide variety of infectious microorganisms and have varying amino acid chain sequences, some of which are similar to those found in human tissues. METHODS: Antibodies to human hsp 27 and hsp 90 in the serum of patients with cystic fibrosis, with and without arthritis, and in normal age and sex matched healthy controls were measured. The severity of the cystic fibrosis was assessed by lung function tests and chest radiographs. The nature of the organisms colonising the lungs was determined by bacteriological examination of sputum. RESULTS: Higher mean titres of serum IgG anti-human hsp 27 and hsp 90 antibodies were found in 50 patients with cystic fibrosis than in healthy controls (hsp 27, 0.25 (95% CI 0.19 to 0.33) versus 0.05 (95% CI 0.04 to 0.07); hsp 90, 0.27 (95% CI 0.22 to 0.32) versus 0.11 (95% CI 0.08 to 0.14)). These antibodies were higher in patients in whom the lungs were colonised with Pseudomonas aeruginosa than in those without infection (hsp 27, 0.41 (95% CI 0.17 to 0.63) versus 0.18 (95% CI 0.10 to 0.27); hsp 90, 0.37 (95% CI 0.18 to 0.57) versus 0.22 (95% CI 0.16 to 0.29)). The eight patients with cystic fibrosis with arthritis had higher anti-hsp 27 antibodies (0.48 (95% CI 0.13 to 0.92)) than the 42 patients without arthritis (0.22 (95% CI 0.17 to 0.30)). CONCLUSIONS: These findings suggest that the arthritis associated with cystic fibrosis, despite being seronegative for rheumatoid factor, was associated with more severe lung disease and with a greater inflammatory response to heat shock proteins.


Assuntos
Anticorpos/sangue , Artrite/etiologia , Fibrose Cística/complicações , Proteínas de Choque Térmico/imunologia , Adolescente , Adulto , Artrite/imunologia , Artrite/metabolismo , Fibrose Cística/metabolismo , Feminino , Proteínas de Choque Térmico HSP90/imunologia , Proteínas de Choque Térmico/sangue , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina G/sangue , Masculino
8.
Prostaglandins ; 36(3): 329-41, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3237996

RESUMO

The mode of PGE2-induced desensitization of the adenylate cyclase of a murine macrophage-like cell line, P388D1 was investigated. The exposure of cells to PGE2 for 60 min induced PGE2-specific desensitization of the adenylate cyclase system which still responded normally to other specific ligand such as isoproterenol, 5'-guanylimidodiphosphate (Gpp(NH)p), or forskolin. The exposure of the cells to PGE2 for 6 hr induced heterologous desensitization, as the responses of adenylate cyclase to PGE2 as well as to isoproterenol or Gpp(NH)p were significantly reduced. The lowest concentration of PGE2 to induce both early homologous and late heterologous desensitization was found to be about two-fold over the KD of the low affinity PGE2-binding sites of P388D1 cells. The early homologous desensitization appeared to be due in part to the reduction in number of PGE2 receptors from the cell surface. The late heterologous desensitization may involve functional and/or structural alteration of Gs proteins, in addition to the reduction of PGE2 receptors from the cell surface.


Assuntos
Adenilil Ciclases/metabolismo , Dinoprostona/farmacologia , Macrófagos/enzimologia , Animais , Linhagem Celular , Radioisótopos do Iodo , Macrófagos/efeitos dos fármacos , Macrófagos/efeitos da radiação , Camundongos , Fatores de Tempo
9.
12.
Clin Sci (Lond) ; 66(3): 323-8, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6319072

RESUMO

To determine whether circadian variation in adrenoceptor function might underlie the 'morning dip' in peak expiratory flow (PEF) rate and its abolition by salbutamol we measured indices of beta-adrenoceptor function (Bmax. and Kd), the ratio FEV1/FVC, and plasma cortisol at 08.00 and 18.00 hours on and off salbutamol (4 mg given orally every 4 h) in five extrinsic asthmatic patients and five normal volunteers. There was a significant circadian variation in receptor numbers (Bmax.) in both the control and asthmatic groups which was not abolished on treatment with salbutamol. Both groups appeared to compensate for loss of receptor number induced by salbutamol administration by increasing receptor affinity. For comparable combinations of drug/time, there was no significant difference between the control and asthmatic groups. We conclude that the 'morning dip' observed in asthmatic patients cannot simply be explained by changes in cell receptor number or affinity, as our results suggest that both groups have intact beta-adrenoceptor function. Nevertheless, our observations of the normal circadian rhythm has important implications for future studies of beta-adrenoceptors in asthmatic patients.


Assuntos
Asma/sangue , Ritmo Circadiano , Linfócitos/metabolismo , Receptores Adrenérgicos beta/metabolismo , Albuterol/uso terapêutico , Asma/tratamento farmacológico , Asma/fisiopatologia , Volume Expiratório Forçado , Humanos , Hidrocortisona/sangue , Cinética , Pico do Fluxo Expiratório , Receptores Adrenérgicos beta/efeitos dos fármacos , Capacidade Vital
14.
J Nat Prod ; 42(6): 615-23, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-541686

RESUMO

Dephinium cashmirianum Royle (Ranunculaceae) has yielded the new base cashmiradelphine (12), together with the known alkaloids anthranoyllycoctonine (9), lycaconitine (15), avadharidine (17), lappaconitine (4), and N-deacetyllappaconitine (7). Pyridinium chlorochromate oxidation of lycoctonine furnished the new aldehyde lycoctonal (11). The arrhythmogenic and heart rate effects of several of these diterpenoidal alkaloids have been measured on the isolated guinea atria. Lappaconitine was arrhythmogenic at 10(-4)M concentrations. But in contrast to the reference drug aconitine, lappaconitine did not increase the heart rate. In anesthetized rabbits injected with lappaconitine, N-deacetyllappaconitine, and lappaconine up to 1 mg/kg, cardiac arrhythmia was quickly observed. Even up to 5 mg/kg, the other substances were non-arrhythmogenic.


Assuntos
Alcaloides/isolamento & purificação , Plantas/análise , Alcaloides/farmacologia , Animais , Arritmias Cardíacas/induzido quimicamente , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Cobaias , Frequência Cardíaca/efeitos dos fármacos , Técnicas In Vitro , Masculino , Coelhos
15.
J Pharm Sci ; 68(6): 705-8, 1979 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-458568

RESUMO

8-Chloroberberine (V), obtained by treatment of oxyberberine (I) with phosphorus oxychloride, is a reactive intermediate. Treatment with ammonia, methylamine, n-propylamine, aniline, and p-toluidine furnished the 8-berberinylidene derivatives IV and VII-X. Reaction of V with malononitrile, ethyl acetoacetate, and ethyl malonate anions yielded the 8-berberinylidene derivatives XII-XIV. Acid hydrolysis of XIV gave 8-berberinylacetic acid (XV) whose reduction provided 8-canadinylacetic acid (XVI). Grignard reagents react readily with V. Methylmagnesium iodide, ethylmagnesium iodide, and benzylmagnesium iodide led to 8,8-dimethyldihydroberberine (XVII), 8,8-diethyldihydroberberine (XIX), and the benzyl derivative XX, respectively. Sodium borohydride reduction of XX gave rise to 8-benzylcanadine (XXI).


Assuntos
Alcaloides de Berberina , Berberina , Berberina/análogos & derivados , Berberina/síntese química , Alcaloides de Berberina/análogos & derivados , Alcaloides de Berberina/síntese química , Fenômenos Químicos , Química , Métodos
19.
Science ; 191(4232): 1166, 1976 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-17781643
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