Estudo do óleo essencial de canela (Cinnamomum zeylanicum L.) para potencial utilização em embalagens alimentares ativas

Os óleos essenciais (OEs) são complexas misturas de compostos voláteis, obtidos, em geral, por destilação a vapor de diferentes partes das plantas. Entre os voláteis presentes nos OEs encontram-se alguns compostos fenólicos. Este trabalho teve como objetivo estudar o OE de canela (Cinnamomum zeylanicum L.) para determinar o seu conteúdo em compostos fenólicos totais e em flavonóides totais por espectrofotometria e quantificar o eugenol, por Cromatografia Líquida de Ultra Eficiência (UHPLC) com Detector de Díodos (DAD). O OE de canela, foi obtido comercialmente. Para a determinação dos compostos fenólicos totais foi utilizado um método que se baseia na reação destes com o reagente Folin-Ciocalteu através da transferência de eletrões, em meio alcalino, dos compostos fenólicos e de outros compostos redutores para o molidbénio, formando compostos azuis. O ensaio para a determinação do teor de flavonóides totais consistiu na complexação de flavonóides com cloreto de alumínio. A coloração do complexo formado foi avaliada espetrofotometricamente. O eugenol foi determinado por UHPLC-DAD, utilizando uma coluna UPLC® BEH Shield RP18 (2,1 x 100 mm, 1,7 µm de tamanho de partícula) e quantificado a 281 nm. Foram utilizadas as seguintes fases móveis em modo gradiente: (A) acetonitrilo e (B) água ultrapura, ambas as fases acidificadas com ácido acético a 0,1% (v/v). O OE de canela apresentou alto teor de compostos fenólicos totais (912 ± 1,13 mg de equivalente de ácido gálico/ g de OE) e de flavonóides totais (371 ± 7,84 mg de equivalente de epicatequina/ g de OE). O fenilpropanóide, eugenol, foi identificado como composto maioritário da canela. O estudo dos compostos fenólicos totais, flavonódes totais e do principal componente do OE de canela, revelou que este óleo essencial tem elevado potencial de aplicação em embalagens alimentares activas que pretendam apresentar propriedades antioxidantes.Regiane Ribeiro-Santos agradece ao projeto "Desenvolvimento de um filme comestível à base de proteína do soro de leite com atividade antioxidante e antimicrobiana utilizando óleos essenciais" (2012DAN807) pelo apoio financeiro e a sua bolsa (BEX 8754/14-4) à Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Histological and ultrastructural analysis of cryopreserved sheep preantral follicles

The aim of this study was to verify the histological and ultrastructural characteristics of sheep preantral follicles after exposure of ovarian tissue to cryopreservation in glycerol (GLY), ethylene glycol (EG), propanediol (PROH) or dimethyl sulfoxide (DMSO) in order to determine the optimum method to store sheep ovarian tissue for later experimental or clinical use. Each ovarian pair from five mixed-breed ewes was divided into 17 fragments. One (control) fragment was immediately fixed for routine histological and ultrastructural studies and the remaining (test) fragments were randomly distributed in cryotubes, equilibrated at 20 °C/20 min in 1.8 mL of minimal essential medium (MEM) containing 1.5 or 3 M GLY, EG, PROH or DMSO and then either fixed for morphological studies to determine their possible toxic effect or frozen/thawed and then fixed to test the effect of cryopreservation on preantral follicles. Histological analysis showed that, compared to control fragments, all cryoprotectants at both concentrations significantly reduced the percentage of normal preantral follicles in ovarian fragments prior to or after cryopreservation. PROH 3.0 M appeared to exert a more toxic effect (P < 0.05) than the other cryoprotectants in noncryopreserved tissues. After freezing/thawing, the highest (P < 0.05) percentages of lightmicroscopical normal preantral follicles were observed in ovarian fragments cryopreserved in EG (1.5 and 3 M) or DMSO (1.5 M). However, transmission electronic microscopical (TEM) examination showed that only the DMSO-cryopreserved preantral follicles had normal ultrastructure. The data suggest that sheep preantral follicles should be cryopreserved with 1.5 M DMSO for later clinical or experimental application

Evapotranspiração e coeficiente de cultura da forrageira cunhã (Clitoria ternatea L.) para diferentes fases fenológicas e épocas do ano

O presente trabalho teve como objetivo determinar a evapotranspiração (ETc) e o coeficiente de cultura (Kc) da cunhã para suas diferentes fases fenológicas e épocas do ano. A pesquisa foi realizada de janeiro de 2009 a fevereiro de 2010, no campo experimental do DTCS-UNEB, Juazeiro, BA. Para determinação da ETc foram efetuadas medidas diárias em evapotranspirômetros de lençol freático constante. O Kc foi determinado pela relação: Kc = ETc/ETo; ETo foi determinada através dos métodos do tanque classe A (TCA) e de Penman-Monteith (padrão FAO). A comparação entre os valores médios diários de Kc obtidos pelo método preconizado pela FAO e o método do TCA foi feita através do coeficiente de determinação. Os resultados mostraram que a maior demanda hídrica da cunhã ocorreu na fase em que a cultura apresentou máximo desenvolvimento vegetativo e produção de vagens; nessa fase, no período da primavera, a ETc média foi de 9,9 mm d-1; no verão, a ETc atingiu valor máximo de até 13,4  mm d-1; para todo o período experimental, em média, o consumo hídrico foi de 6,7 mm d-1. O Kc determinado com base no método do TCA foi cerca de 26% menor do que o Kc determinado com base no método de Penman-Monteith,  variando de 0,36 a 1,52 para as diferentes fases fenológicas da cultura; a realização de pesquisa para determinação da ETc e do Kc in situ é fundamental, pois contribui para um planejamento eficiente da irrigação

Osmotic tolerance and freezability of isolated caprine early-staged follicles

Isolated caprine early-staged follicles were submitted to osmotic tolerance tests in the presence of sucrose, ethylene glycol (EG), or NaCl solutions and were exposed to and cryopreserved (by slow or rapid cooling) in MEM alone or MEM supplemented with sucrose, EG (1.0 or 4.0 M), or both. When follicles were exposed to 1.5 M NaCl, only 2% of the follicles were viable, whereas 87% of the follicles were viable after exposure to 4.0 M EG. Regarding exposure time, the highest percentage of viable follicles was obtained when follicles were exposed for 10 min to 1.0 M EG + 0.5 M sucrose; exposure for 60 s to 4.0 M EG + 0.5 M sucrose also maintained high percentage viability in follicles. Slow cooling in the presence of 1.0 M EG + 0.5 M sucrose (75%) or rapid cooling in the presence of 4.0 M EG + 0.5 M sucrose (71%) resulted in a significantly higher proportion of viable follicles than all other treatments (P < 0.05). A 24-h culture of frozen-thawed follicles was used to assess survival; only slow-frozen follicles showed viability rates similar to control follicles (64% vs. 69% respectively; P > 0.05). Interestingly, the percentage of viable rapid-cooled follicles (59%) was similar to that obtained after in vitro culture of conventional slow-cooled follicles but was significantly lower than that in controls. Thus, in addition to determining improved procedures for the exposure of follicles to EG and sucrose before and after freezing of caprine early-staged follicles, we report the development of rapid- and slow-cooling protocols

The Balanced Scorecard - як основа прийняття управлінських рішень

Frozen-thawed ovarian cortical fragments (1 mm(3)) were autotransplanted to the uterus of completely ovariectomized goats. The grafts developed preovulatory follicles, accompanied by estrous behavior and a rise in plasma E(2) levels, demonstrating successful cryopreservation and transplantation

Genomic Surveillance of Yellow Fever Virus Epizootic in São Paulo, Brazil, 2016 – 2018

São Paulo, a densely inhabited state in southeast Brazil that contains the fourth most populated city in the world, recently experienced its largest yellow fever virus (YFV) outbreak in decades. YFV does not normally circulate extensively in São Paulo, so most people were unvaccinated when the outbreak began. Surveillance in non-human primates (NHPs) is important for determining the magnitude and geographic extent of an epizootic, thereby helping to evaluate the risk of YFV spillover to humans. Data from infected NHPs can give more accurate insights into YFV spread than when using data from human cases alone. To contextualise human cases, identify epizootic foci and uncover the rate and direction of YFV spread in São Paulo, we generated and analysed virus genomic data and epizootic case data from NHPs in São Paulo. We report the occurrence of three spatiotemporally distinct phases of the outbreak in São Paulo prior to February 2018. We generated 51 new virus genomes from YFV positive cases identified in 23 different municipalities in São Paulo, mostly sampled from NHPs between October 2016 and January 2018. Although we observe substantial heterogeneity in lineage dispersal velocities between phylogenetic branches, continuous phylogeographic analyses of generated YFV genomes suggest that YFV lineages spread in São Paulo at a mean rate of approximately 1km per day during all phases of the outbreak. Viral lineages from the first epizootic phase in northern São Paulo subsequently dispersed towards the south of the state to cause the second and third epizootic phases there. This alters our understanding of how YFV was introduced into the densely populated south of São Paulo state. Our results shed light on the sylvatic transmission of YFV in highly fragmented forested regions in São Paulo state and highlight the importance of continued surveillance of zoonotic pathogens in sentinel species

Impaired Performance of Broiler Chickens Fed Diets Naturally Contaminated with Moderate Levels of Deoxynivalenol

Mycotoxin exposure is common in the poultry industry. Deoxynivalenol (DON) is usually detected at levels below the maximum threshold (5000 ppb), but depending on diet and age, broiler performance can be affected. We evaluated the effects of 900 ppb and 2300 ppb DON on the performance, intestinal morphometry, and lesion scores of broiler chickens. One-day-old male Ross broilers (n = 736) were divided into 4 treatments with 8 replicates each, and a pen containing 23 birds was the experimental unit. The animals were fed diets naturally contaminated with two levels of DON: 900 (Low DON—LD) or 2300 (Moderate DON—MD) ppb, with or without activated charcoal, over 28 days. After this, all birds were fed a marginally DON-contaminated diet without charcoal. During the first 28 days, body weight gain (BWG) and feed conversion ratio (FCR) were significantly impaired when broilers were fed a MD diet without activated charcoal. Even after feeding a marginally contaminated diet from D28–35, birds previously fed the MD diet presented a significantly lower performance. The villus height:crypt depth (VH:CD) ratio was significantly higher in the ileum from 14-day-old broilers fed the MD when compared with the LD diet. At D28, the MD diet caused decreased villus height (VH) and increased crypt depth (CD), affecting VH:CD ratio in both intestinal segments, with higher levels in the jejunum from 28-day-old broilers fed a non-supplemented LD diet. Broiler production was negatively affected by DON, even at moderate levels (2300 ppb)

Analyzing the antibacterial effects of food ingredients : model experiments with allicin and garlic extracts on biofilm formation and viability of Staphylococcus epidermidis

To demonstrate different effects of garlic extracts and their main antibiotic substance allicin, as a template for investigations on the antibacterial activity of food ingredients. Staphylococcus epidermidis ATCC 12228 and the isogenic biofilm-forming strain ATCC 35984 were used to compare the activity of allicin against planktonic bacteria and bacterial biofilms. The minimal inhibitory concentration (MIC) and the minimum biofilm inhibitory concentration (MBIC) for pure allicin were identical and reached at a concentration of 12.5 μg/mL. MBICs for standardized garlic extracts were significantly lower, with 1.56 and 0.78 μg/mL allicin for garlic water and ethanol extract, respectively. Biofilm density was impaired significantly at a concentration of 0.78 μg/mL allicin. Viability staining followed by confocal laser scanning microscopy showed, however, a 100% bactericidal effect on biofilm-embedded bacteria at a concentration of 3.13 μg/mL allicin. qRT-PCR analysis provided no convincing evidence for specific effects of allicin on biofilm-associated genes. Extracts of fresh garlic are more potent inhibitors of Staphylococcus epidermidis biofilms than pure allicin, but allicin exerts a unique bactericidal effect on biofilm-embedded bacteria. The current experimental protocol has proven to be a valid approach to characterize the antimicrobial activity of traditional food ingredients

Cadmium Modulates Biofilm Formation by Staphylococcus epidermidis

The aim of the study was to evaluate the effect of cadmium exposure on Staphylococcus epidermidis (ATCC 35984) biofilm formation. Bacteria were cultured in the absence or presence of different concentrations (0-50 mu M) of cadmium. Biofilm formation and bacterial viability were assessed. Quantitative Real Time-PCR (qRT-PCR) was used to determine the mRNA expression of molecular markers of S. epidermidis biofilm formation and dispersion. S. epidermidis biofilm formation was stimulated (p <0.001) by 1.56 and 3.13 mu M cadmium. Confocal laser scanning microscopy (CLSM) analysis confirmed an increase in biofilm thickness (23 and 22 mu m, versus 17.8 mu m in the controls) after exposure to 1.56 or 3.13 mu M cadmium, respectively. qRT-PCR was performed showing the up-regulation of atlE, embp, aap, icaA and icaB after exposure to 3.13 mu M cadmium. Taken together, these findings show that cadmium at low, sub-toxic concentrations acts as inducer of S. epidermidis biofilm formation