Assessment of antioxidant potential of Moringa stenopetala leaf extract

This study was conducted to assess the antioxidant potential of Moringa stenopetala leaf obtained from a private garden in Bahir Dar City and powdered Moringa leaf purchased from a supermarket in Bahir Dar City by using ferric reducing antioxidant power, 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity, peroxide value and conjugated diene hydroperoxide assays. The powdered Moringa stenopetala leaf extract was invariably found to have a higher antioxidant capacity than the purchased Moringa powder. In the conjugated diene hydroperoxide and peroxide value assays, sunflower oil was used as an oxidation substrate. Both peroxide value and conjugated diene concentration for sunflower oil containing extracts of Moringa leaf and purchased Moringa powder were found to be lower than the corresponding values observed for the control showing the effectiveness of the extracts in delaying oxidation of the oil. The total phenolic content, in terms of mg gallic acid equivalent per 100 g of dry weight of sample was found to be 92.8 ±1.01 and 75.5 ± 2.28 for, respectively, powdered leaves of M. stenopetala and  purchased powder of Moringa leaf. The antioxidant capacity of the powdered Moringa stenopetala leaf and purchased Moringa powder were found to be, respectively, 442.0±10.58 and 291.3±15.52 mg of ascorbic acid equivalent per 100 g of dry weight of plant sample in the FRAP assay. The corresponding values for the powdered Moringa stenopetala leaf and purchased Moringa powder in the DPPH assay were found to be, respectively, 144.0±0.53, 138.8±1.05 mg of ascorbic acid equivalent per 100 g of dry weight of the sample. This difference in antioxidant capacity of these two samples can be attributed to differences in their total phenolic content. It is suggested that this antioxidant potential of the leaves of Moringa stenopetala may underlie the widespread use of the plant in traditional medicine.Key words: Moringa stenopetala, Antioxidant potential, Ferric reducing antioxidant power (FRAP), 2,2-diphenyl- 1-picrylhydrazyl (DPPH) radical, Folin-Ciocalteu’s phenol reagent (FCR), Peroxide value (PV)

Hydrolytic Activity of Free and Immobilized Cellulase

Cellulase is an enzymatic complex which synergically promotes the degradation of cellulose to glucose. The adsorption behavior of cellulase from Trichoderma reesei onto Si wafers or amino-terminated surfaces was investigated by means of ellipsometry and atomic force microscopy (AFM) as a function of temperature. Upon increasing temperature from (24 +/- 1) to (60 +/- 1) degrees C, adsorption of cellulase became faster and more pronounced and the mean roughness of cellulase adsorbed layers increased. In the case of cellulase adsorbed onto Si wafers, Arrhenius`s plot allowed us to estimate the adsorption energy as 24.2 kJ mol(-1). The hydrolytic activity of free cellulase and cellulase immobilized onto Si wafers was tested using cellulose dispersions as substrates. The incubation temperature ranged from (37 +/- 1) to (60 +/- 1) degrees C. The highest efficiency was observed at (60 +/- 1) degrees C. The amount of glucose produced by free cellulase was similar to 20% higher than that obtained from immobilized cellulase. However, immobilizing cellulase onto Si wafers proved to be advantageous because they could be reused six times while retaining their original activity level. Such an effect was attributed to surface hydration, which prevents enzyme denaturation. The hydrolytic activity of cellulase immobilized onto amino-terminated surfaces was slightly lower than that observed for cellulase adsorbed onto Si wafers, and reuse was not possible.FAPESP Fundacao de Amparo A Pesquisa do Estado de Sao Paulo e Conselho Nacional de Pesquisa e DesenvolvimentoFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

A novel inhibitor of complement C5 provides structural insights into activation

Abstract The complement system is a crucial part of innate immune defences against invading pathogens. The blood-meal of the tick Rhipicephalus pulchellus lasts for days, and the tick must therefore rely on inhibitors to counter complement activation. We have identified a novel class of inhibitors from tick saliva, the CirpT family, and generated detailed structural data revealing their mechanism of action. We show direct binding of a CirpT to complement C5 and have determined the structure of the C5-CirpT complex by cryo-electron microscopy. This reveals an interaction with the peripheral macro globulin domain 4 (C5_MG4) of C5. To achieve higher resolution detail, the structure of the C5_MG4-CirpT complex was solved by X-ray crystallography (at 2.7 Å). We thus present the novel fold of the CirpT protein family, and provide detailed mechanistic insights into its inhibitory function. Analysis of the binding interface reveals a novel mechanism of C5 inhibition, and provides information to expand our biological understanding of the activation of C5, and thus the terminal complement pathway

North by East piece on Maine towns that are doing away with annual town meetin

North by East piece on Maine towns that are doing away with annual town meetings in favor of referendums. Of Maine\u27s 491 municipal governments, some 50 have representative councils, another 20 have town meetings by referendum, and the rest hold town meetings

Barriers to providing quality emergency obstetric care in Addis Ababa, Ethiopia: Healthcare providers’ perspectives on training, referrals and supervision, a mixed methods study

Background: Increasing women’s access to and use of facilities for childbirth is a critical national strategy to improve maternal health outcomes in Ethiopia; however coverage alone is not enough as the quality of emergency obstetric services affects maternal mortality and morbidity. Addis Ababa has a much higher proportion of facility-based births (82%) than the national average (11%), but timely provision of quality emergency obstetric care remains a significant challenge for reducing maternal mortality and improving maternal health. The purpose of this study was to assess barriers to the provision of emergency obstetric care in Addis Ababa from the perspective of healthcare providers by analyzing three factors: implementation of national referral guidelines, staff training, and staff supervision. Methods: A mixed methods approach was used to assess barriers to quality emergency obstetric care. Qualitative analyses included twenty-nine, semi-structured, key informant interviews with providers from an urban referral network consisting of a hospital and seven health centers. Quantitative survey data were collected from 111 providers, 80% (111/138) of those providing maternal health services in the same referral network. Results: Respondents identified a lack of transportation and communication infrastructure, overcrowding at the referral hospital, insufficient pre-service and in-service training, and absence of supportive supervision as key barriers to provision of quality emergency obstetric care. Conclusions: Dedicated transportation and communication infrastructure, improvements in pre-service and in-service training, and supportive supervision are needed to maximize the effective use of existing human resources and infrastructure, thus increasing access to and the provision of timely, high quality emergency obstetric care in Addis Ababa, Ethiopia. Electronic supplementary material The online version of this article (doi:10.1186/s12884-015-0493-4) contains supplementary material, which is available to authorized users