70 research outputs found
Enriching nutritive value of cassava root by yeast fermentation
Cassava (Manihot esculenta) is extensively cultivated throughout the tropics and subtropics regions due to its ability to grow in diverse soil conditions and minimal management. Experiments were made to study the cassava root fermentation by yeasts in order to enhance the nutritive value of their products (fresh pulp and chips). Both cassava chip (CC) and fresh cassava root pulp (FCR) samples were fermented by Saccharomyces cerevisiae in solid-liquid media fermentation conditions during 132 hours and dried at 30ºC. Products were analyzed for proximate composition, mineral composition, essential aminoacids and antinutrient content. There were increases (p A mandioca (Manihot esculenta) é extensivamente cultivada nas regiões tropical e subtropical devido à sua habilidade de crescer em diveresas condições de clima e manejo. Experimentos foram efetuados para estudar o aumento do valor nutritivo de subprodutos derivados de raízes de mandioca (polpa fresca e raspas) por processos de fermentação. Amostras de raspas (RM) e de polpa fresca (PF) foram fermentadas por Saccharomyces cerevisiae, em condições de meio sólido-líquido durante 132 horas e secas a 30ºC. Foram avaliados a composição aproximada, composição mineral, aminoácidos essenciais e conteúdo de antinutrientes dos produtos obtidos. Houve aumentos (p < 0.01) em proteínas (30,4% em RM e 13,5% in PF) e conteúdo de gorduras (5,8% em RM e 3,0% in PF). Os subprodutos de mandioca fermentados por S. cerevisiae apresentaram baixos conteúdos de ácido hidrocianídrico (RM, 0,5 mg kg-1 e PF 47,3 mg kg-1). Houve aumento considerável de lisina nas raspas fermentadas (RMF). Valores aceitáveis de cor, textura e aroma das raspas de mandioca enriquecidas formam obtidos após 132 de bioprocessamento. Sugere-se que a RMF pode ser nutricionalmente melhorada para alimentação animal pelo uso de S. cerevisiae
Diving into the vertical dimension of elasmobranch movement ecology
Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements
Inorganic UV filters
Nowadays, concern over skin cancer has been growing more and more, especially in tropical countries where the incidence of UVA/B radiation is higher. The correct use of sunscreen is the most efficient way to prevent the development of this disease. The ingredients of sunscreen can be organic and/or inorganic sun filters. Inorganic filters present some advantages over organic filters, such as photostability, non-irritability and broad spectrum protection. Nevertheless, inorganic filters have a whitening effect in sunscreen formulations owing to the high refractive index, decreasing their esthetic appeal. Many techniques have been developed to overcome this problem and among them, the use of nanotechnology stands out. The estimated amount of nanomaterial in use must increase from 2000 tons in 2004 to a projected 58000 tons in 2020. In this context, this article aims to analyze critically both the different features of the production of inorganic filters (synthesis routes proposed in recent years) and the permeability, the safety and other characteristics of the new generation of inorganic filters
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