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1.
An Acad Bras Cienc ; 95(3): e20230187, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37909570

RESUMEN

The present work aimed to characterize and compare the catalytic properties of amylases from Cunninghamella echinulata and Rhizopus microsporus. The highest production of amylase by C. echinulata, 234.94 U g-1 of dry substrate (or 23.49 U mL-1), was obtained using wheat bran as a substrate, with 50-55% initial moisture and kept at 28 °C for 48 h. The highest production of amylases by R. microsporus, 224.85 U g-1 of dry substrate (or 22.48 U mL-1), was obtained cultivating wheat bran with 65% initial moisture at 45 °C for 24 h. The optimal activity of the amylases was observed at pH 5.0 at 60 °C for C. echinulata enzymes and at pH 4.5 at 65 °C for R. microsporus. The amylases produced by C. echinulata were stable at pH 4.0-8.0, while the R. microsporus enzymes were stable at pH 4.0-10.0. The amylases produced by C. echinulata remained stable for 1 h at 50 °C and the R. microsporus amylases maintained catalytic activity for 1 h at 55 °C. The enzymatic extracts of both fungi hydrolyzed starches from different plant sources and showed potential for liquefaction of starch, however the amylolytic complex of C. echinulata exhibited greater saccharifying potential.


Asunto(s)
Amilasas , Cunninghamella , Amilasas/química , Fibras de la Dieta , Almidón , Concentración de Iones de Hidrógeno
2.
Biosci. j. (Online) ; 32(4): 1040-1048, july/aug. 2016.
Artículo en Inglés | LILACS | ID: biblio-965644

RESUMEN

Xylanases are useful in several industrial segments, including pulp and paper bleaching, animal feed, and bread-making processes. However, the industrial use of these enzymes is closely related to its production cost and its catalytic properties. The process of solid state fermentation enables the use of agro-industrial residues as substrates for microbial cultivation and enzymes production, reducing costs. In the present study, different cultivation parameters were evaluated for the xylanase production by the thermophilic fungus Thermoascus aurantiacus, by solid state fermentation, using agro-industrial residues as substrates. High production of xylanase (1701.9 U g-1 of dry substrate) was obtained using wheat bran containing 65% of initial moisture, at 120 h of cultivation, and 45°C. The xylanase showed optimal activity at pH 5.0 and 75°C; its stability was maintained at pH 3.0­11.0. The enzyme retained its catalytic potential after 1 h, at 75°C. The enzymatic extract produced under optimized conditions showed reduced activities of endoglucanase and FPase. Our results, including the xylanase production by T. aurantiacus in low-cost cultivation medium, high structural stability of the enzyme, and reduced cellulolytic activity, encourage the application of this enzymatic extract in pulp and paper bleaching processes.


As xilanases apresentam aplicabilidade em diferentes segmentos industriais, como: branqueamento de papel e celulose, ração animal e panificação. No entanto, a utilização industrial dessas enzimas está intimamente relacionada com seu custo de produção e suas propriedades catalíticas. O processo de fermentação em estado sólido possibilita o uso de resíduos agroindustriais como substratos, para o cultivo microbiano e produção de enzimas, reduzindo o custo da produção enzimática. No presente trabalho, diferentes parâmetros de cultivo foram avaliados para produção de xilanase por cultivo em estado sólido do fungo termófilo Thermoascus aurantiacus, utilizando resíduos agroindustriais como substratos. A maior produção de xilanase, 1701,9 U g-1 de substrato seco, foi obtida no cultivo em farelo de trigo, contendo 65% de umidade inicial, em 120 horas de cultivo a 45°C. A xilanase produzida apresentou atividade ótima em pH 5,0 a 75°C, mantendo sua estabilidade em pH 3,0 a 11,0. A enzima manteve seu potencial catalítico após 1 h a 75°C. O extrato enzimático produzido nas condições otimizadas apresentou reduzida atividade de endoglucanase e FPase. Os resultados obtidos no presente trabalho (produção de xilanase pelo fungo em meios de cultivo de baixo custo, elevada estabilidade estrutural da enzima e reduzida atividade celulolítica) estimulam a aplicação desse complexo enzimático em processos de branqueamento de papel e celulose.


Asunto(s)
Papel , Residuos , Celulosa , Thermoascus , Fermentación
3.
Cien Saude Colet ; 20(11): 3319-28, 2015 Nov.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-26602710

RESUMEN

OBJECTIVE: assessing the nutritional status and body fat distribution in children and adolescents with cystic fibrosis. METHOD: Fifty-six (56) 8-18 year old patients were assessed for fat distribution by dual energy X-ray absorptiometry, for nutritional status by height/age, and for body mass index to age and dietary intake by 24-hour dietary recall. RESULTS: Approximately 50% of the sample showed adequate nutritional status. Most of it showed inadequate caloric and lipid intake. BMI/age was the nutritional indicator that best showed the increased percentage of trunk fat, android/gynecoidratio and trunk fat/total fat ratio. Patients with Pancreatic Insufficiency and eutrophic individuals showed higher median android/gynecoidratio. CONCLUSION: Increased abdominal adiposity was evidenced by DXA. The BMI did not identify decreased lean body mass. However, when body mass was high, it was significant for abdominal adiposity. The anthropometric assessment of patients with cystic fibrosis should be associated with body composition and body fat distribution to obtain an earlier malnutrition and cardiometabolic risk factor diagnosis.


Asunto(s)
Distribución de la Grasa Corporal , Fibrosis Quística , Estado Nutricional , Absorciometría de Fotón , Adolescente , Composición Corporal , Índice de Masa Corporal , Niño , Femenino , Humanos , Masculino
4.
Ciênc. Saúde Colet. (Impr.) ; 20(11): 3319-3328, Nov. 2015. graf
Artículo en Portugués | LILACS | ID: lil-766420

RESUMEN

O objetivo deste estudo é avaliar o estado nutricional e a distribuição da gordura corporal em crianças e adolescentes com fibrose cística. Foram realizadas avaliação da distribuição de gordura corporal por meio da absorciometria de duplo feixe de energia, do estado nutricional por estatura/idade e índice de massa corporal/idade e a ingestão dietética pelo recordatório alimentar de 24horas, em 56 pacientes com idade entre 8 e 18 anos. Aproximadamente 50% da amostra apresentou estado nutricional adequado. A maioria apresentou a ingestão calórica e de lipídios inadequadas. O IMC/I foi o indicador nutricional que melhor evidenciou o aumento do percentual de gordura do tronco, razão androide/ginecoide e razão gordura tronco/gordura total. Os pacientes com Insuficiência Pancreática e os eutróficos apresentaram razão mediana androide/ginecoide maior. O aumento da adiposidade abdominal foi evidenciado pela DXA. O IMC/I não identificou a diminuição da massa magra corporal, mas quando aumentado foi significativo para adiposidade abdominal. Pacientes com fibrose cística devem associar a avaliação antropométrica à composição corporal e à distribuição de gordura corporal para um diagnóstico mais precoce de desnutrição e fatores de risco cardiometabólico.


Objective : assessing the nutritional status and body fat distribution in children and adolescents with cystic fibrosis. Method : Fifty-six (56) 8-18 year old patients were assessed for fat distribution by dual energy X-ray absorptiometry, for nutritional status by height/age, and for body mass index to age and dietary intake by 24-hour dietary recall. Results : Approximately 50% of the sample showed adequate nutritional status. Most of it showed inadequate caloric and lipid intake. BMI/age was the nutritional indicator that best showed the increased percentage of trunk fat, android/gynecoidratio and trunk fat/total fat ratio. Patients with Pancreatic Insufficiency and eutrophic individuals showed higher median android/gynecoidratio. Conclusion : Increased abdominal adiposity was evidenced by DXA. The BMI did not identify decreased lean body mass. However, when body mass was high, it was significant for abdominal adiposity. The anthropometric assessment of patients with cystic fibrosis should be associated with body composition and body fat distribution to obtain an earlier malnutrition and cardiometabolic risk factor diagnosis.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Estado Nutricional , Fibrosis Quística , Distribución de la Grasa Corporal , Composición Corporal , Absorciometría de Fotón , Índice de Masa Corporal
5.
HU rev ; 35(1): 11-18, jan.-mar. 2009. graf, tab
Artículo en Portugués | LILACS | ID: lil-530942

RESUMEN

Com o objetivo de verificar a validade do diagnostico clínico para a candidíase vulvovaginal e utilizando como padrão-ouro a cultura de secreção vaginal, realizou-se uma análise em 93 pacientes atendidas pelo serviço de Ginecologia da Faculdade de Medicina de Barbacena. As pacientes procuraram o serviço por demanda espontânea, para consulta ginecológica de rotina. Foram submetidas a anamnese e exame ginecológico, com o intuito de avaliar os dados epidemiológicos, sintomas e sinais clínicos. Foi colhido material para a cultura da secreção vaginal, semeada em ágar Sabouraud. A prevalência da Candida foi de 47,91%. A acurácia do exame clínico foi de 0,78, tendo sensibilidade (S) de 82,6% e especificidade (E) de 74,46%. Os achados que tiveram relevância foram a presença de fluxo grumoso (S: 82,60% e E: 78,72%), a citologia positiva para Candida (S: 60,86% e E: 95,74%) e a presença de processo inflamatório (S: 60,86% e E: 87,23%). Os valores de OR foram estatisticamente significantes e todos obtiveram um p<0,001.


To verify the validity of clinical diagnosis of vulvovaginal candidiasis by itself and associated with fresh examination using the culture of vaginal secretion as gold standard. An analysis was carried out on 93 patients that were seen by the department of Gynecology from Faculdade de Medicina de Barbacena, which looked forward the service by spontaneous demand for routine gynecological appointment. They were subjected to a anamnesis for the evaluation of clinical symptoms and epidemiological data, the gynecological exam was performed and each data was discriminated. To make the clinical diagnosis, widely disseminated criteria by literature were used, such as vulvovaginal intense itching and burning, swelling and vulvar erythema, dyspareunia, vaginal secretions, white, flocculated, thick and inodorous. The last step was to collect material to vaginal secretion culture and sent it to a laboratory of microbiology to grow on Sabouraud agar, until 48 hours after the collection. In the study the prevalence of vulvovaginal candidiasis in patients, based on the culture, was 47.91%. The accuracy of clinical examination was a 0.78, and sensitivity (S) of 82.6% and specificity (E) of 74.46%. The findings that have great relevance were the presence of flocculated flow (S: 82.60% and E: 78.72%), positive cytology for Candida (S: 60.86% and E: 95.74%) and the presence of inflammatory process (S: 60.86% and E: 87.23%). The odds ratio of these items were also statistically significant and all get a p<0,001.


Asunto(s)
Humanos , Femenino , Candidiasis , Candidiasis/diagnóstico , Examen Ginecologíco , Examen Ginecologíco/efectos adversos
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