Our data suggest that impaired activity of myeloperoxidase (MPO) may play an important role in the dysfunction of neutrophils from hyperglycemic rats. Neutrophil biochemical pathways include the NADPH oxidase system and the MPO enzyme. They both play important role in the killing function of neutrophils. The effect of hyperglycemia on the activity of these enzymes and the consequences with regard to Candida albicans phagocytosis and the microbicidal property of rat peritoneal neutrophils is evaluated here. The NADPH oxidase system activity was measured using chemiluminescence and cytochrome C reduction assays. MPO activity was measured by monitoring HOCl production, and MPO protein expression was analysed using Western blot and immunofluorescence. C. albicans phagocytosis and death were evaluated by optical microscopy using the May-Grunwald-Giemsa staining method. ROS generation kinetic was slightly delayed in the diabetic group. MPO expression levels were higher in diabetic neutrophils; however, MPO activity was decreased in these same neutrophils compared with the controls. C. albicans phagocytosis and killing were lower in the diabetic neutrophils. Based on our experimental model, the phagocytic and killing functions of neutrophil phagocytosis are impaired in diabetic rats because of the decreased production of HOCl, highlighting the importance of MPO in the microbicidal function of neutrophils.

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This study aimed to develop a chitosan-based hydrogel containing a mixture of flavonoids isolated from the leaves of Passiflora edulis Sims and to evaluate its stability, antioxidant properties, and wound healing effects on cutaneous lesions in diabetic rats. in vitro studies were carried out to evaluate the biocompatibility and flavonoid release from the chitosan hydrogel. in vivo wound healing studies were conducted on male Wistar rats, where the injured tissue was removed for histological analysis and determination of lipid peroxidation, superoxide dismutase activity, and glutathione peroxidase activity. From the histological analysis and macroscopic evaluation of the contraction of the wounds, it was observed that the formulation presented wound healing properties. In addition, treatment of the wound with the formulation stimulated the antioxidant defense system, suggesting a beneficial effect during the treatment of skin lesions in diabetic rats, especially in the first few days after wounding. According to these results, we can conclude that the chitosan hydrogel containing the flavonoid analyzed in this study has potential use as dressings in the treatment of wounds. K E Y W O R D S antioxidant, chitosan, flavonoid, hydrogel, Passiflora edulis, wound healing

Recebido em26/8/08; aceito em 23/6/09; publicado na web em 13/11/09 COFFEE BIOACTIVE COMPOUNDS: IN VITRO ANTIOXIDANT ACTIVITY OF GREEN AND ROASTED COFFEES BEFORE AND AFTER DECAFFEINATION. This study aimed to evaluate the effect of coffee decaffeination with dichloromethane on the in vitro antioxidant activity of this matrix. It were determined the content of total phenolics, chlorogenic acid and caffeine of the coffee samples. The assessment of the antioxidant potential was investigated by DPPH radical scavenging method, reducer power and Fe 2+ chelation activity. The process of decaffeination and roasting caused changes in the levels of the compounds investigated. The results show that the decaffeination by the dichloromethane method reduces the in vitro antioxidant potential of coffee.Keywords: coffee; decaffeination; antioxidant activity. INTRODUÇÃOO café é um dos mais valiosos produtos da economia global e sua bebida é uma das mais consumidas no mundo.1 O alto consumo mundial do produto tem estimulado o desenvolvimento de estudos relacionados à atividade biológica do grão e de constituintes do café verde e, especialmente, do café torrado que é utilizado para preparar diferentes tipos de bebidas. Diferentes constituintes do café têm sido sugeridos como potencialmente quimioprotetores em diferentes sistemas quí-micos e biológicos; a explicação estaria nos numerosos antioxidantes presentes na bebida, como os ácidos clorogênicos, melanoidinas, que são produtos formados na reação de Maillard, e a cafeína.O café é um alimento singular, pois apesar da degradação parcial dos compostos fenólicos durante a torração, possui atividade antioxidante devido ao desenvolvimento de outros compostos bioativos. 2Por definição, a atividade antioxidante é a capacidade de um composto inibir a degradação oxidativa.3 Assim, a atividade antioxidante, especialmente a inibição da reação em cadeia, de produtos naturais e alimentos tem sido um parâmetro importante na determinação do valor dietético dos mesmos. 4 O interesse pela descoberta de antioxidantes novos e seguros de fontes naturais tem aumentado, principalmente para prevenir o dano oxidativo às células vivas. O uso de antioxidantes sintéticos tem diminuído devido à suspeita de atividade como promotores de carcinogênese. O papel de antioxidantes dietéticos e seus benefícios para a saúde têm atraído grande atenção nos últimos anos, especialmente aqueles extraídos de plantas. 5A busca pelo café sem cafeína tem mobilizado estudiosos do mundo inteiro para atender à demanda crescente de pessoas que querem se livrar dos efeitos colaterais provocados por essa substância estimulante, como a insônia.O café descafeinado responde por 10% do consumo mundial de café 6 e com isso há a necessidade de estudos sobre a composição química do mesmo. A descafeinação é realizada nos grãos verdes inteiros, antes do processo de torração. A maioria dos métodos de descafeinação existentes utiliza solventes para extração da cafeína, como o diclorometano, clorofórmio, etanol, acetona, água e outros, sendo o...