Potencial estabilizante de éster de sacarose em suco de graviola (Annona muricata, L.)

Esteres de sacarose são compostos com propriedades tensoativas (biosurfactantes), isto é, capazes de reduzir a tensão superficial e promover a emulsificação de líquidos imiscíveis. Como todas as emulsões, o suco de graviola não é fisicamente estável e é propenso a uma separação de fases. O objetivo do presente trabalho foi avaliar a aplicação do éster de sacarose na estabilização de emulsões de suco de graviola. O éster de sacarose foi adicionado às amostras de suco de graviola nas proporções de 1:10, 1:50 e 1:100 (éster de sacarose:suco de graviola) e caracterizado de acordo com a tensão superficial, índice de emulsificação, potencial zeta e análise microscópica. A análise microscópica apresentou maior aglomerado de glóbulos na amostra B (1:10, éster de sacarose:suco de graviola, p/v). Os resultados das demais análises indicaram que a amostra C (1:50, éster de sacarose:suco de graviola, p/v) apresentou a melhor estabilidade, com uma tensão superficial de 35 N/m e um índice de emulsificação de 50.4 % durante 24 horas de experimento

Biosurfactant Production by Pseudomonas aeruginosa and Burkholderia gladioli Isolated from Mangrove Sediments Using Alternative Substrates

Biosurfactants are surface-active agents produced by a variety of microorganisms. To make biosurfactant production economically feasible, several alternative carbon sources have been proposed. This study describes biosurfactant production by strains of Pseudomonas aeruginosa and Burkholderia gladioli isolated from mangrove sediments in Northeastern Brazil and cultured in mineral media enriched with waste cooking oil. The biosurfactants were tested for drop collapse, emulsion formation and stability and surface tension. P. aeruginosa performed better both at lowering the surface tension (from 69 to 28 mN/m) and at forming stable emulsions (approximately 80%) at 48 hours of culture. The strains tested in this study were found to be efficient biosurfactant producers when cultured on substrates enriched with vegetable oil. DOI: http://dx.doi.org/10.17807/orbital.v8i5.77

Enzymatic synthesis of sugar esters and their potential as surface-active stabilizers of coconut milk emulsions

Sugar esters are compounds with surfactant properties (biosurfactants), i.e., capable of reducing the surface tension and promote the emulsification of immiscible liquids. On the other hand, as with all emulsions, coconut milk is not physically stable and is prone to phase separation. Therefore, the aim of this work was to evaluate the synthesis of fructose, sucrose and lactose esters from the corresponding sugars using Candida antarctica type B lipase immobilized in two different supports, namely acrylic resin and chitosan, and evaluate its application in the stabilization of coconut milk emulsions. The enzyme immobilized on chitosan showed the highest yield of lactose ester production (84.1%). Additionally, the production of fructose ester was found to be higher for the enzyme immobilized on the acrylic resin support (74.3%) as compared with the one immobilized on chitosan (70.1%). The same trend was observed for the sucrose ester, although with lower percentage yields. Sugar esters were then added to samples of fresh coconut milk and characterized according to their surface tension, emulsification index and particle size distribution. Although the microscopic analysis showed similar results for all sugar esters, results indicated lactose ester as the best biosurfactant, with a surface tension of 38.0 N/m and an emulsification index of 54.1%, when used in a ratio of 1:10 (biosurfactant: coconut milk, v/v) for 48 hour experiments.The authors acknowledge the AlBan Programme (European Union Programme of High Level Scholarships for Latin America) for financial support of N. Lopes through the research grant E07D401544BR. Furthermore, the authors acknowledge the Chemical Engineering Department e Federal University of Ceara (Campus of Pici - Brazil) and Biotechnology Laboratory - Federal University of Ceara for enabling the use of their laboratory facilities

Cladosporium tenuissimum URM 7803: a promising new β-galactosidase producer

The Cladosporium genus, defined by Link in 1816, is one of the largest and most heterogeneous Hyphomycetes genus. It comprises more than 189 species still rarely explored biotechnologically. One of the most studied microbial enzymes, -galactosidase is a glycoside hydrolase enzyme that catalyzes the hydrolysis of -galactosides into monosaccharides through the breaking of a glycosidic bond. Recently, new studies comprising new microbial sources of -galactosidase, presenting biotechnologically interesting characteristics, have been encouraged. In this context, the present study evaluated the production of -galactosidase by a new isolate of Cladosporium tenuissimum. A C. tenuissimum inoculum was prepared adding 107 spore/mL in sterile saline solution 0.85% (w/v) NaCl containing 0.01% (w/v) Tween 80 and added to fermentation medium for enzyme production. The fermentation medium, composed of (% w/v): lactose (2), peptone (0.4), yeast extract (0.4) and salts (KH2PO4 (0.2), Na2HPO4.12H2O (0.8) and MgSO4.7H2O (0.025), pH 6.5, was maintained at 28° C and 180 rpm for 13 days. One sample (50 mL erlenmeyer) was removed every 24 hours and -galactosidase activity was evaluated using ONPG (ortho-Nitrophenyl--galactoside) method. The results showed maximum -galactosidase production by C. tenuissimum URM 7803 on thirteenth day, displayed enzymatic activity of 462.13 U/mL. The C. tenuissimum URM 7803 isolate proved to be a powerful new -galactosidase producer with potential application for food processing.info:eu-repo/semantics/publishedVersio

Biosurfactant Production by Pseudomonas aeruginosa and Burkholderia gladioli Isolated from Mangrove Sediments Using Alternative Substrates

Biosurfactants are surface-active agents produced by a variety of microorganisms. To make biosurfactant production economically feasible, several alternative carbon sources have been proposed. This study describes biosurfactant production by strains of Pseudomonas aeruginosa and Burkholderia gladioli isolated from mangrove sediments in Northeastern Brazil and cultured in mineral media enriched with waste cooking oil. The biosurfactants were tested for drop collapse, emulsion formation and stability and surface tension. P. aeruginosa performed better both at lowering the surface tension (from 69 to 28 mN/m) and at forming stable emulsions (approximately 80%) at 48 hours of culture. The strains tested in this study were found to be efficient biosurfactant producers when cultured on substrates enriched with vegetable oil. DOI: http://dx.doi.org/10.17807/orbital.v8i5.77

Identifying adolescents at risk for depression: a prediction score performance in cohorts based in three different continents:A Prediction Score Performance in Cohorts Based in 3 Different Continents

OBJECTIVE: Prediction models have become frequent in the medical literature, but most published studies are conducted in a single setting. Heterogeneity between development and validation samples has been posited as a major obstacle for the generalization of models. We aimed to develop a multivariable prognostic model using sociodemographic variables easily obtainable from adolescents at age 15 to predict a depressive disorder diagnosis at age 18 and to evaluate its generalizability in 2 samples from diverse socioeconomic and cultural settings. METHOD: Data from the 1993 Pelotas Birth Cohort were used to develop the prediction model, and its generalizability was evaluated in 2 representative cohort studies: the Environmental Risk (E-Risk) Longitudinal Twin Study and the Dunedin Multidisciplinary Health and Development Study. RESULTS: At age 15, 2,192 adolescents with no evidence of current or previous depression were included (44.6% male). The apparent C-statistic of the models derived in Pelotas ranged from 0.76 to 0.79, and the model obtained from a penalized logistic regression was selected for subsequent external evaluation. Major discrepancies between the samples were identified, impacting the external prognostic performance of the model (Dunedin and E-Risk C-statistics of 0.63 and 0.59, respectively). The implementation of recommended strategies to account for this heterogeneity among samples improved the model’s calibration in both samples. CONCLUSION: An adolescent depression risk score comprising easily obtainable predictors was developed with good prognostic performance in a Brazilian sample. Heterogeneity among settings was not trivial, but strategies to deal with sample diversity were identified as pivotal for providing better risk stratification across samples. Future efforts should focus on developing better methodological approaches for incorporating heterogeneity in prognostic research

Nascidos vivos com fenda palatina e labial: estudo epidemiológico

Introduction: Cleft lip and palate is a congenital malformation resulting from the inadequate fusion of bony structures during embryonic development. The etiology is multifactorial, involving genetic and environmental factors. Methodology: This study constitutes a descriptive epidemiological analysis focusing on the investigation of cases of live births with cleft lip and palate in Brazil. Data collection will be conducted through the Live Birth Information System (SINASC) during the period from 2017 to 2021. Results: The gender distribution of live births with cleft lip and palate indicates a male predominance in the sample, representing approximately 58.49% (n=4,390) of the total. Meanwhile, the percentage of female individuals is approximately 41.01% (n=3,078). The category "Unknown" has a very small representation, accounting for only 0.51% (n=38) of the sample. Conclusion: It is observed that live births with cleft lip and palate should not be overlooked. There is a significant number of cases each year, necessitating further related studies to provide solutions in society that directly benefit those affected.Introdução: A fenda labial e palatina é uma malformação congênita resultante da não fusão das estruturas ósseas adequadas durante o desenvolvimento embrionário. A etiologia é multifatorial, envolvendo fatores genéticos e ambientais. Metodologia: Este estudo constitui uma análise epidemiológica descritiva com enfoque na investigação dos casos de nascidos vivos com fenda labial e palatina no Brasil. A coleta de dados será realizada por meio do Sistema de Informações sobre Nascidos Vivos (SINASC) durante o período de 2017 a 2021. Resultado: A distribuição de gênero dos nascidos vivos com fenda labial e palatina indica que há uma maioria masculina na amostra, representando cerca de 58,49%  (n= 4.390) do total. Enquanto isso, a porcentagem de pessoas do sexo feminino é de aproximadamente 41,01% (n = 3.078) A categoria "Ignorado" tem uma representação muito pequena, com apenas 0,51% (n = 38) da amostra. Conclusão: Observa-se que os nascidos vivos com fenda labial e palatina não devem ser negligenciados. Há uma quantidade significativa de nascidos por ano, sendo indispensável mais estudos relacionados, a fim de trazer soluções na sociedade que beneficiem diretamente os acometidos

Physical activity levels during COVID-19 pandemic and its associated factors in patients with Chagas disease

BackgroundA better understanding of the consequences of the Coronavirus Disease 2019 (COVID-19) pandemic on lifestyle of patients with Chagas disease (ChD) is of paramount importance to facilitate the implementation of intervention strategies tailored to this specific population.ObjectiveThe present study aimed to evaluate the level of physical activity (PA) in Chagas disease (ChD) patients during the Coronavirus Disease 2019 (COVID-19) pandemic and its main associated factors.MethodsThis is a cross-sectional study with 187 patients of both sexes, aged ≥18 years, followed in a national infectious disease center (Rio de Janeiro, Brazil). The level of PA was determined by the International Physical Activity Questionnaire short version and expressed in terms of total volume of physical activity (PA) (MET-minutes per week). Individuals were classified as physically active following the 2020 World Health Organization PA guideline. The exposure variables were age, sex, race, marital status, schooling, income per capita, number of rooms per domicile, number of residents per domicile, body mass index, clinical form of ChD, COVID-19 antibodies, comorbidities, self-reported anxiety, self-reported depression, self-reported fear, and self-reported sadness. The association between the exposure variables with total PA (as a continuous variable) was determined using univariate and multivariate linear regression models.ResultsMean age was 61.1 ± 11.6 years. Most (62%) were women and self-declared their race as mixed (50.8%). The percentage of physically active individuals according to was 52%. The variables independently associated with total PA levels were non-white race (Exp β = 1.39; 95% CI 1.02 to 1.90), dyslipidemia (Exp β = 0.73; 95% CI 0.56 to 0.95) and self-reported depression during quarantine (Exp β = 0.71; 95% CI 0.52 to 0.96).ConclusionNon-white race was positively associated with total levels of PA, while dyslipidemia, and self-reported depression during quarantine were negatively associated with total levels of PA. The identification of associated factors can facilitate the development of tailored strategies to increase PA levels ChD patients