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Extração e prospecção de metabólitos secundários de folhas de Annona glabra L. e análise de atividade sobre o crescimento de coleóptilos de trigo e de microorganismos
(Universidade Federal de São Carlos, 2013-06-20) Matsumoto, Reginaldo Sadao; Lima, Maria Inês Salgueiro; https://lattes.cnpq.br/2171993314203162; https://lattes.cnpq.br/9384309905070395
The record of Annonaceae substances increases every year, as well as the isolation of bioactive compounds in this family. Currently there is a growing demand in the discovery of natural substances less toxic than synthetic products that are herbicides, algaecides and bactericides. For this reason bio-prospection, identification and production of secondary metabolites has become increasingly important. Numerous studies on the chemical composition of Annona glabra L. were made using their seeds, fruits, stems and fewer leaves. However, the major activities studied are related to the inhibition of tumor cells. One of the major difficulties of conducting phytochemical studies is to obtain sufficient amounts of purified product for the biological testing and its economic exploitation through the subsequent synthesis of these substances. Besides the amount of substance isolated is also important to reduce costs related to such a process. The present study was designed from the preliminary results on the allelopathic effects of extracts of Annona glabra on seed germination and also due to the need for optimization of extraction of bioactive substances for use as algaecides and fungicides. Two procedures were assistants to extraction (ultrasound-assisted extraction (UAE) and microwave assisted extraction (MAE)) in bio-directed activity assays on wheat-etiolated coleoptiles. After the optimization process, an extraction mass (UAE) was performed to isolate and identify the major substances: (1) (-)-Kaur-16-en-19-oic acid, (2) β- sitosterol, (3) Stigmasterol, (4) ent-19-methoxy-19-oxokauran-17-oic acid, (5) 16α- hydro-19-acetoxy-ent-kauran-17-oic acid (annoglabasin B), (8) Asimicin and minor substances (6) ent-17-hydroxykaur-15-en-19-oic acid e (7) ent-15β,16β-epoxy-17- hydroxy-kauran-19-oic acid. Wherein the substance 5 was highly inhibitory against coleoptiles followed by the substances 4 and 8. The acetonic extract showed growth retardation of Selenastrum capricornutum in concentrations of 125-175 mgL-1 and fully inhibitory above 200 mgL-1 and IC50, at 96h, was 145 mgL-1. The oomycete Pythium aphanidermatum was inhibited at concentrations above 125 μg.disc-1. These results highlight the importance of bioprospecting of substances of this species and opening up opportunities for future commercial uses.
Produção de etanol a partir de xilose com glicose isomerase e Saccharomyces cerevisiae coimobilizadas em gel de alginato
(Universidade Federal de São Carlos, 2013-06-20) Aquino, Patrícia Marina de; Giordano, Raquel de Lima Camargo; https://lattes.cnpq.br/6003805840377188
In this work, it was studied the simultaneous isomerization and fermentation of xylose to ethanol (SIF) using xylose isomerase (XI) and S. cerevisiae co-immobilized in calcium alginate gel. XI was immobilized on chitosan gel activated with glutaraldehyde (IXI-Ch). The influence of the concentration of enzyme/yeast in the reactor, the pH, temperature and yeast strain on yield and selectivity in ethanol was studied. The concentrations of enzyme and yeast in the reactor were varied by changing the mass of IXI-Ch and yeast per gram of alginate solution, maintaining fixed the ratios of biocatalyst weight: volume of medium in the reactor (1:1). The SIFs were carried out in batch with xylose (65g.L-1), antibiotics and other salts. The first experiment, with 16% Itaiquara® yeast and 5% enzyme biocatalyst (% wenzyme or yeast/wbiocatalyst) showed that pH drop occurred during the test, preventing full conversion of xylose, due to reduced enzyme activity. calcium carbonate (0.5-1.0%) was then included in the biocatalyst, which maintained the pH between 5,2 to 5,6, allowing complete conversion of the sugar at all concentrations tested (%Yeast -Enzyme in biocatalyst): 5-20, 17-5, and 10 yeast (Itaiquara ®) with 5, 10 and 20-. The maximum ethanol productivity, 2,44 ± 0,26g.L-1.h- 1 was obtained for the highest cell concentration and the highest selectivity ethanol/xylitol, 2,57 ± 0.4 and 2,42 ± 0,01 for the highest enzyme concentrations (10 and 20% with 10% yeast). These results indicated that the highest concentration of xylulose favored more selectivity to ethanol. Fermentation was then performed using no enzyme in biocatalyst with a prior isomerized syrup concentrated in xylulose containing 58g.L-1 xylulose and 9g.L-1 xylose and another with xylose only. At first, xylulose was completely assimilated in 5 hours, xylose was barely consumed in both assays, and ethanol selectivity was lower than that obtained in the SIF tests. Xylitol show thus to be produced mainly from xylulose and selectivity contrary to expectations did not directly increase with increasing xylulose concentration, indicating that the formation of ethanol/xylitol depends not only on external xylulose, and it is probably finely regulated in yeast. The concentrations of enzyme and yeast 20 and 10% (equivalent to 100gderived.L-1 reactor and 50gwd.L-1 reactor) were selected as the best, which were used to study the influence of pH and temperature, and also different strains. The increase of initial pH from 5.6 to 6.5 did not improve the productivity, yield, neither selectivity in ethanol. Temperatures tested for Itaiquara ® were 32, 35 and 37 ° C, and for industrial strains CAT-1 and BG-1: 32, 37 and 40 ° C. Viability remained above 90% for all assays at 24 hours. All three strains showed increased selectivity in ethanol with temperature reduction, obtaining the maximum selectivity for industrial strains (3,06 ± 0,24 - CAT-1 and 3,19 ± 0,11 BG-1) with yield and productivity equal or greater than those obtained in higher temperatures. At 32 ° C and pH 5.6, Itaiquara ® showed lower conversion time, but lower selectivity, while the BG-1, demonstrated the highest selectivity, but low conversion and productivity. The strain CAT-1 combines high productivity, 2,17 ± 0,17 g.L-1.h-1, and selectivity, 3,06 ± 0,24, with 90% conversion in 9 hours, 32 ° C, which is apparently the best performance among the tested yeasts. The results were very promising, indicating the technical feasibility of producing ethanol from xylose with the biocatalyst developed.
O desenvolvimento da viticultura irrigada na região de Juazeiro - BA e Petrolina - PE: o trabalho na contramão do discurso dominante
(Universidade Federal de São Carlos, 2013-06-20) Leite, Ângelo Antônio Macêdo; Alves, Francisco José da Costa; https://lattes.cnpq.br/9183120186518337; https://lattes.cnpq.br/2885580573978250
This work aims to explain the dynamic of the production of fruit in the São Francisco Valley, mainly through the analysis of the working process. Basically, the appreciation and the accumulation of capitals rise from the economic underdevelopment and subordination of the farm workers. Some authors explain the development of fruit and grape production in this region by the local presence of natural characteristics and by its localization. This thesis goes further, and tries to demonstrate how there is a process of modernization of the agriculture in this region, turning subsistence products producer farm workers labour force into free labour force, which to reproduce itself generation after generation, is sold, and, through the sell of labour force, increases the capital value. In the last years, the agriculture production of the region of Juazeiro and Petrolina turned from a subsistence production (typical of the semiarido region) into an entrepreneurial activity, oriented to external high added value markets, based on a complex and advanced productive process and an irrigation system using São Francisco river s water. Some authors explain this new economic dynamics by the rational use of natural and structural resources and undervalue the analysis of man work, that is the core of the analysis, as we consider, the sole work aggregates value to the materials. This search was performed through a qualitative investigation. We interviewed several social actors: land owners, agricultural production managers, consultants and, mainly, land workers. Through their answers we tried to capture the essence of the production dynamics, of their lifestyle and work conditions. The search revealed the dynamic of irrigated fruit production, mainly grapefruit for exportation, is very similar to the industrial one, which aims to control the yield of the workers and the production of capital through the use of new technologies. The development of capitalistic grape fruit production in the region has grown mainly because of the occurrence of six linked processes, besides the others factors presented by other authors: 1- Direct intervention of the State through the development of policies, valorising capitalistic agri-business; 2- Expulsion of small farmers, who produced at subsistence level close to or into the irrigated region; 3- concentration of latifundia in irrigated regions and in close areas; 4- availability and use of local labour force, cheap and subordinate to the capital; 5- use of modern technologies, which enabled the production of grapes varieties to be exported to great food distribution chains; 6- industrial-style oriented management, stimulating the acceleration of working rhythm and the competition among workers.
Dimensões exclusoras e transformadoras no processo de trabalho dos profissionais de saúde de Unidades de Saúde da Família no apoio ao aleitamento materno exclusivo
(Universidade Federal de São Carlos, 2013-06-20) Targino, Daniela Aparecida Salgado; Fabbro, Márcia Regina Cangiani; https://lattes.cnpq.br/6978014098495031; https://lattes.cnpq.br/7089471643751585
The Estratégia de Saúde da Família (ESF) (In English: The Family Health Strategy) is presented as a substitutive model to health care, according to the principles of the Sistema Único de Saúde (In English: the Unified Health System). It is a strategy that provides a comprehensive care to family, not only for intense situations but also for chronic deseases, with the objective of promoting and keeping health. Therefore, although the ESF is, in effect, a viable tool for the support and promotion of the Aleitamento Materno Exclusivo (AME) (In English: Exclusive Maternal Breastfeeding) health professionals should be willing to assume a dialogical approach with users that shares scientific knowledge and experiences. Therefore, the promotion and support of AME is the focus of this study, with the ESF as a research field. The goal was to analyze the exclusionary and transformative components of the work process in the family health care teams to support exclusive maternal breastfeeding. The Theoretical Framework used was constituted by the Dialogic Learning and the Dialogic Feminism and the methodological framework by the Critical Communicative Methodology. This is a qualitative study, developed with the staff of five family health units in a town in Minas Gerais, in 2011 and 2012. Data were collected using the technique of Communicative focus groups, and analyzed according to the Critical Communicative Methodology, highlighting the transformative and the exclusionary aspects regarding the support that the ESF provides to the AME. Results allowed to conclude that, within the category "Personal Experiences with the Maternal Breastfeeding transformative elements are more present than the exclusionary ones, showing that when the time of breastfeeding is longer than six months, a greater certainty exists regarding the orientations for the promotion and support of the maternal breastfeeding. In the category of "Promoting and supporting maternal breastfeeding", exclusionary elements were more present, demonstrating that even though the ESF is a reference in the support the AME, it is still influenced by an instrumental rationality, that gives place to care practices of little success. This influence creates obstacles for dialogic educational practices to favor transformation. The dialogue between researcher and participants provided by the communicative focus group allowed consensus about the fact that the promotion and support of the AME should emerge from a transformation regarding the way health orientations are performed. Therefore, the assumption of an egalitarian dialogue; in which breastfeeding is recognized in the social and cultural contexts of those who live it, respecting their knowledge and experiences and looking for the transformation of these contexts; should be present.
Ação bioindicadora da entomofauna em canavial plantado entre aleias de essências florestais nativas
(Universidade Federal de São Carlos, 2013-06-20) Favetta, Marcela Marques da Silva; Margarido, Luiz Antonio Correia; https://lattes.cnpq.br/5685663057214334; FAVETTA, M. M. S.
The present work aims to study the acquisition of environmental information through the analysis of insect fauna in an agroforestry system consisting of alleys native trees planted between strips of different widths cultivated with cane sugar. These are important complementary information for the commercial deployment of large areas of this agroforestry system that seeks to mitigate the undesirable impacts caused by sugar cane monoculture. The option for this type of analysis is linked to the practical and low cost, using simple equipment, apply without interfering with routine activities of production or the development of culture. Another aspect is the possibility of obtaining information in the short term, considering the insects are sensitive to environmental stimuli, numerous and capable of producing several generations in a short period of time. Besides that respond quickly to disturbances in their habitat features and changes in structure and function of ecosystems. Catches of the specimens were held bimonthly and lines of trees, and the tracks in culture for three complete cycles of cane sugar. We analyzed the interactions of these populations in relation to climatic aspects and between different environments formed by sugar cane planted between three different species of native trees; guapuruvu, cedar and yellow ipe. Were captured 84,644 specimens, and their records used in ecological analyzes. The results showed that initially environments formed by different combinations of tree-cane behaved differently. During studies of these environments were coalescing gradually showing a tendency to operate in the future as a single community without major conflicts. This would be a desirable feature about the purpose of implementing such agroforestry system. The spatial distribution of insect fauna occurred randomly in all environments studied. Environmental analysis with relatively simple methodology has generated consistent information.