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1.
Food Chem ; 135(3): 1533-8, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22953890

RESUMO

Brazilian artisanal "Coalho" cheeses from six Northeast towns were investigated as a functional food based on their peptide profiles and antioxidant, zinc-binding and antimicrobial activities. The peptides (WSP) from "Coalho" cheese showed high antioxidant activity, the best value of TEAC being 2223±10.10µM, which means 91.1±0.43% oxidative inhibition and peptide concentration for IC(50) of 7mg/mL (21µg of peptides) for sample from the town of Correntes. The smallest TEAC value (1896±17µM), which means 75.9±0.7% oxidative inhibition and IC(50) of 10.5mg/mL (31.5µg of peptide), was obtained for samples from the town of São Bento do Una. The zinc-binding activities were: Arcoverde (72.21±0.24%) Cachoeirinha (75.02±0.02%), Capoeiras (61.78±0.65%), Correntes (75.47±0.5%), São Bento do Una (75.41±0.15%), and Venturosa (74.36±0.04%). The WSP extracts showed antimicrobial activity against Enterococcus faecalis, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. All the results obtained suggest that "Coalho" cheese has potential as a functional food.


Assuntos
Antibacterianos/análise , Antioxidantes/análise , Queijo/análise , Alimento Funcional/análise , Peptídeos/análise , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Brasil , Peptídeos/farmacologia
2.
Bioresour Technol ; 101(6): 1595-602, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19945280

RESUMO

Invertase was covalently immobilized on polyurethane (PU), inox plate covered with plast-film layer and ferromagnetic azide-Dacron. The immobilization processes, physico-chemical parameters and a model for coupling reactions were studied. The preliminary studies for selection of the support showed that the best activity was obtained for PU treated with HCl, polyethylenimine and glutaraldehyde (156.7+/-4.9 U/g support). All plast-film-invertase derivatives did not show activity and the Dacron-invertase derivative showed an activity of 105.39 U/g support. The invertase immobilized in presence of substrate (10% w/v sucrose) was the most efficient (832.74+/-1.48 U/g support). The optimal pH was shifted from 4.5 (free enzyme) to 5.0 (immobilized derivative) and optimal temperature was not affected. Activation energy values of free enzyme, Dacron-invertase and PU-invertase were 32.4+/-0.34 kJ/mol, 33.4+/-0.36 kJ/mol and 44.0+/-0.67 kJ/mol, respectively. The PU-invertase could be used over 2 months without considerable activity loss (68.5% activity retention) and retained 12.6% (287.97+/-27.9U/g support) of the activity after five cycles.


Assuntos
Biotecnologia/métodos , Enzimas Imobilizadas/química , Polietilenotereftalatos/química , Poliuretanos/química , beta-Frutofuranosidase/química , Azidas/química , Carboidratos/química , Glutaral/química , Hidrazinas/química , Concentração de Íons de Hidrogênio , Magnetismo , Teste de Materiais , Polietilenoimina/química , Proteínas/química , Sacarose/química
3.
Artigo em Inglês | MEDLINE | ID: mdl-17453706

RESUMO

Candida rugosa lipase has been covalently immobilized on ferromagnetic azide polyethyleneterepthalate (Dacron) with specific activity retention of 16% for 4-nitrophenyl palmitate and 24% for hydrolysis of triolein in hexane. The immobilized enzyme was more thermal stable than the soluble one, retaining 78.8% of the activity after 1 h at 60 degrees C. Also, this immobilized derivative was stable at the storage at 4 degrees C. It has been used 5 cycles for pNPP hydrolysis without loss of activity. Soluble and immobilized Candida rugosa lipase showed a Michaelian behavior for fatty acid 4-nitrophenyl esters and different apparent K(M) values: 0.110 mM and 0.124 mM (4-nitrophenyl palmitate - C16); 0.193 mM and 0.235 mM (4-nitrophenyl laurate - C12) and 0.206 mM and 0.119 mM (4-nitrophenyl butyrate - C4), respectively. The immobilized lipase was more efficient for catalyzing the hydrolysis of 4-nitrophenyl esters with short chain length fatty acid (4-NPB - C4) than soluble enzyme. The ferromagnetic Dacron-lipase derivative was able to catalyze the synthesis of triolein from glycerol and oleic acid with 50% of conversion after 72 h at 40 degrees C.


Assuntos
Biotecnologia/métodos , Candida/enzimologia , Enzimas Imobilizadas/metabolismo , Lipase/metabolismo , Polietilenotereftalatos , 2-Propanol , Ésteres/metabolismo , Temperatura Alta , Cinética , Magnetismo , Solventes , Especificidade por Substrato
4.
Rev. bras. farmacogn ; 12(supl.1): 132-135, 2002. tab, ilus
Artigo em Português | LILACS | ID: lil-528784

RESUMO

Antimicrobial activities of “babaçu” (Orbignya martiana), “cardo santo” (Argemone mexicana), “mentrasto” (Ageratum conyzoides), “cavalinha” (Equisetum yeamalis) and “terramicina” (Alternanthera brasiliana), used by Brazilian population as antiinflamatory medicine, were studied on Staphylococcus aureus. The freezer dried hydroalcoholic extracts solutions were tested for 7 strains of Staphylococcus aureus, which two of those are methicillin resistant (MRSA). The diffusion method on agar-agar, using holes technique, with tetracycline chlorydrate as standard. “Babaçu”, “cardo santo” and “terramicina” showed antimicrobial activity, within of those “terramicina” inhibited 6 strains, presenting zone inhibition of 22 mm compared to standard antibiotic (34 mm), except the seventh strain which was also tetracycline resistant.

5.
Rev. microbiol ; 23(3): 199-205, jul.-set. 1992. tab, graf
Artigo em Português | LILACS | ID: lil-279945

RESUMO

Dentre 16 cepas de fungos testados, foram selecionadas 4 cepas como melhores produtoras da atividade sacarose fosforitase.Scytalidium sp e Colletotrichum gloesporioides apresentaram atividade sacarose fosforitase predominantemente intracelular, enquanto que em Sclerotinia sclerotiorum e Monilia sitophila, a atividade foi predominante extracellular.Altos valores de temperatura ótimas 50ºC e 40ºC foram encontrados respectivamente para a enzima de M.sitophila e para as outras 3 cepas selecionadas.Como sacarose fosforilase de M.sitophila foi a mais termoestável, retendo 90-95 por cento de sua atividade fosforolítica inicial após pré-tratamento na ausência de substrato, a 50ºC-70ºC durante 30 minutos, ela foi selecionada para estudos posteriores.A maior produçäo da enzima (340 UI/L de meio cultivado ou 0, 336 UI/mg de proteínas) foi obtida no início da fase estacionária de crescimento da M.sitophila cultivada em extrato de inhame com 0, 15 por cento de sulfato de amônio, à temperatura ambiente(28ºC-30ºC) e agitaçäo continua.Foram afetuados estudos preliminares de imobilizaçäo do extrato bruto da sacarose fosforilase, por adsorçäo em DEAE-celulose e ligaçäo covalente em quitosana.o melhor resultado foi obtido com o derivado imobilizado em quitosana o qual reteve 12 por cento de proteínas e 216 por cento da atividade específica inicial


Assuntos
Sacarose/análise , Enzimas , Fungos/classificação
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