35 resultados para alimentos funcionais


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The corn cob is an agricultural by-product still little used, this in part due to the low knowledge of the biotechnological potential of their molecules. Xylan from corn cobs (XSM) is a polysaccharide present in greater quantity in the structure of plant and its biotechnology potential is little known. This study aimed to the extraction, chemical characterization and evaluation of biological activities of xylan from corn cobs. To this end, corncobs were cleaned, cut, dried and crushed, resulting in flour. This was subjected to a methodology that combines the use of alkaline conditions with waves of ultrasound. After methanol precipitation, centrifugation and drying was obtained a yield of 40% (g/g flour). Chemical analysis indicated a high percentage of polysaccharides in the sample (60%) and low contamination by protein (0.4%) and phenolic compounds (> 0.01%). Analysis of monosaccharide composition indicated the presence of xylose:glucose:arabinose:galactose:mannose:glucuronic acid in a molar ratio 50:20:15:10:2.5:2.5. The presence of xylan in the sample was confirmed by nuclear magnetic resonance (¹H and ¹³C) and infrared spectroscopy (IR). Tests were conducted to evaluate the antioxidant potential of XSM. This showed a total antioxidant capacity of 48.45 EAA/g sample. However, did not show scavenging activity of superoxide and hydroxyl radical and also reducing power. But, showing a high capacity chelating iron ions with 70% with about 2 mg/mL. The ability to XSM to influence cell proliferation in culture was also evaluated. This polymer did not influence the proliferation of normal fibroblast cells (3T3), however, decreased the rate of proliferation of tumor cells (HeLa) in a dose-dependent, reaching an inhibition of about 50% with a concentration around 2 mg/mL. Analyzing proteins related to cell death, by immunoblotting, XSM increases the amount of Bax, Bcl-2 decrease, increase cytochrome c and AIF, and reduce pro-caspase-3, indicating the induction of cell death induced apoptosis dependent and independent of caspase. XSM did not show anticoagulant activity in the PT test. However, the test of activated partial thromboplastin time (aPTT), XSM increased clotting time at about 5 times with 600 μg of sample compared with the negative control. The presence of sulfate on the XSM was discarded by agarose gel electrophoresis and IR. After carboxyl-reduction of XSM the anticoagulant activity decreased dramatically. The data of this study demonstrate that XSM has potential as antioxidant, antiproliferative and anticoagulant compound. Future studies to characterize these activities of XSM will help to increase knowledge about this molecule extracted from corn and allow their use in functional foods, pharmaceuticals and chemical industries.

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The antioxidant activity of aqueous extracts of five edible tropical fruits (Spondias lutea, Hancornia speciosa, Spondias purpurea, Manilkara zapota and Averrhoa carambola) was investigated using different methods. The amount of phenolic compounds was determined by the Folin-Ciocalteu reagent. The M. zapota had Total Antioxidant Capacity (TAC) higher than the other fruits. Extracts showed neither reducing power nor iron chelation (between 0.01 and 2.0 mg/mL). H. speciosa exhibited the highest superoxide scavenging activity (80%, 0.5 mg/mL). However, at high concentrations (8.0 mg/mL) only A. carambola, S. purpurea and S. lutea scavenging 100% of radicals formed. M. zapota and S. purpurea had higher phenolic compound levels and greater OH radical scavenging activity (92 %, 2.0 mg/mL). Antiproliferative activity was assessed with 3T3 fibroblasts and cervical tumor cells (HeLa). The most potent extract was S. purpurea (0.5 mg/mL), which inhibited HeLa cell proliferation by 52%. The most fruits showed antioxidant and antiproliferative properties, characterizing them as functional foods.

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Tropical fruits have been extensively studied due to their functional potential attributed to the presence of natural bioactive compounds. The exotic fruit jambolan (Syzygium cumini) has been reported for its appreciable amount of phenolic compounds, especially anthocyanins and antioxidant capacity. Nevertheless, there are hardly any derived jambolan products in the Brazilian market. In addition to that, considerable volumes of fruit are lost due to their high perishability. Dried fruits have become an important fruit market segment due to its weight and volume reduction and decreased transportation and storage costs. Thus, this study evaluated the jambolan pulp submitted to spouted bed drying (JLJ) and lyophilization (JLI), besides assessing the drying impact on the final product. In order to achieve this, the process performance was calculated and compared, as well the physicochemical and bioactive characteristics (moisture, water activity (aw), solubility, hygroscopicity, density, color, structure through images obtained by scanning electron microscopy (SEM), concentration of bioactive (total phenolic compounds (TPC), anthocyanins, proanthocyanidins and ascorbic acid) and antioxidant activity. The results showed drying efficiency higher than 60% for both products and that JLJ group showed higher moisture and water activity when compared to the JLI group (p<0.05). The two types of drying were able to produce stable final product in the microbiological point of view, given that both showed aw < 0.6. The final products exhibited high solubility (73.7 to 81.6%) and low hygroscopicity (9.8 to 11.6%), desirable characteristics for dehydrated foods. Despite the losses caused by drying, the dried jambolan pulp by both methods showed high TPC (468.6 to 534.0 mg GAE/100g dm), anthocyanins (from 491.9 to 673.4 mg. eq. cyanidin-3-glicoside/100g dm), proanthocyanidins (66.9 to 76.6 mg QTE/g dm) and ascorbic acid (156.4 to 186.8 mg/100 g dm). Taken together, the results of this study reveal spouted dried and freeze dried jambolan pulp as bioactive-rich natural products with suitable physicochemical and functional characteristics to be used as food ingredients. The data also demonstrate the drying techniques as rational strategies for the exploitation of the exotic fruit jambolan

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The corn cob is an agricultural by-product still little used, this in part due to the low knowledge of the biotechnological potential of their molecules. Xylan from corn cobs (XSM) is a polysaccharide present in greater quantity in the structure of plant and its biotechnology potential is little known. This study aimed to the extraction, chemical characterization and evaluation of biological activities of xylan from corn cobs. To this end, corncobs were cleaned, cut, dried and crushed, resulting in flour. This was subjected to a methodology that combines the use of alkaline conditions with waves of ultrasound. After methanol precipitation, centrifugation and drying was obtained a yield of 40% (g/g flour). Chemical analysis indicated a high percentage of polysaccharides in the sample (60%) and low contamination by protein (0.4%) and phenolic compounds (> 0.01%). Analysis of monosaccharide composition indicated the presence of xylose:glucose:arabinose:galactose:mannose:glucuronic acid in a molar ratio 50:20:15:10:2.5:2.5. The presence of xylan in the sample was confirmed by nuclear magnetic resonance (¹H and ¹³C) and infrared spectroscopy (IR). Tests were conducted to evaluate the antioxidant potential of XSM. This showed a total antioxidant capacity of 48.45 EAA/g sample. However, did not show scavenging activity of superoxide and hydroxyl radical and also reducing power. But, showing a high capacity chelating iron ions with 70% with about 2 mg/mL. The ability to XSM to influence cell proliferation in culture was also evaluated. This polymer did not influence the proliferation of normal fibroblast cells (3T3), however, decreased the rate of proliferation of tumor cells (HeLa) in a dose-dependent, reaching an inhibition of about 50% with a concentration around 2 mg/mL. Analyzing proteins related to cell death, by immunoblotting, XSM increases the amount of Bax, Bcl-2 decrease, increase cytochrome c and AIF, and reduce pro-caspase-3, indicating the induction of cell death induced apoptosis dependent and independent of caspase. XSM did not show anticoagulant activity in the PT test. However, the test of activated partial thromboplastin time (aPTT), XSM increased clotting time at about 5 times with 600 μg of sample compared with the negative control. The presence of sulfate on the XSM was discarded by agarose gel electrophoresis and IR. After carboxyl-reduction of XSM the anticoagulant activity decreased dramatically. The data of this study demonstrate that XSM has potential as antioxidant, antiproliferative and anticoagulant compound. Future studies to characterize these activities of XSM will help to increase knowledge about this molecule extracted from corn and allow their use in functional foods, pharmaceuticals and chemical industries.

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Camu-camu (Myrciaria dubia H.B.K. (McVaugh)) is a native Amazon fruit, recognized worldwide as one of the main natural sources of ascorbic acid. Due to its great acidity, this fruit is generally consumed after processing into juice or as ingredient in food preparations. As a co-product of the camu-camu processing, a significant amount of agroindustrial residue is generated. Despite the studies showing the bioactive value and biological potential of the fruit, few studies have approached the possible processing techniques, transformation and preservation of camu-camu fruits and its agroindustrial pomace. Therefore, the present work has the objective of evaluating two different drying processes applied to camu-camu pomace (peel and seeds with residual pulp), freeze drying and hot air drying, in order to obtain a functional fruit product. This thesis was divided into three stages: the first one shows the studies related to the freeze drying and hot air drying, where we demonstrated the impact of the selected drying techniques on the bioactive components of camu-camu, taking the fresh pomace as the control group. Among the investigated conditions, the groups obtained at 50ºC and 4 m/s (SC50) and 80ºC and 6 m/s (SC80) were selected as for further studies, based on their ascorbic acid final content and Folin-Ciocalteau reducing capacity. In addition to SC50 and SC80, the fresh pomace (RF) and freeze dried (RL) samples were also evaluated in these further stages of the research. Overall, the results show higher bioactive concentration in the RF samples, followed by RL, SC50 and SC80. On the second step of the research, the antioxidant, antimicrobial and antienzymatic activities were evaluated and the same tendency was observed. It was also reported, for the first time in the literature, the presence of syringic acid in dried camu-camu pomace. In the third and final stage of the research, it was investigated the effect of dried camu-camu on aging and neuroprotective disorders, using the in vivo model C.elegans. It was observed that camu-camu extracts were able to modulate important signaling genes relevant to thermal and oxidative stresses (p < 0.05). The polar acid, polar basic and polar neutral fractions obtained from the low molecular extracts of SC50 were able to extend the lifespan of wild type N2 C. elegans in 20% and 13% (p < 0.001). Results also showed that the paralysis induced by the β1-42 amyloid was significantly (p < 0.0001) retarded in CL4176 worms. Similarly, the camu-camu extracts attenuated the dopaminergic induction associated to Parkinson’s disease. Finally, a global analysis of the data presented here reveal that the camu-camu pomace, a co-product obtained from the industrial processing of a native Brazilian fruit, is a relevant natural source of health relevant compounds. This thesis, shows for the first time, the multifunctionality of camu-camu pomace, a natural resource still underexploited for scientific, commercial and technological purposes.

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This thesis aimed to evaluate the implementation of the Food Acquisition Program(PAA) through CONAB RN in the period of 2003-2010 with the perception of all agents involved in the implementation of the government program.For the methodological trajectory it was adopted a descriptive bibliographical and documentary approach with triangular qualitative and quantitative, also called evaluative research.The theoretical model was supported by the authors Draibe (2001), Aguilar and Ander-Egg (1994) and Silva(2001), among others, that focused on family farming and evaluation of implementation of public policy having as a category of analysis the size implementation of policy and the latter divided into 10 theoretical dimensions.The universe consisted of three groups: the first were the managers and technicians from CONAB(RN and Brasilia), totaling 15 subjects. The second group was of associations/cooperatives that participated in the programin 2010, totaling a sample in each access of 15 representatives. The third group of subjects totaled with 309 representatives of governmental and non-governmental organizations that received donations of food for the same period. Semi-structured interviews and forms were adopted as instruments of data collection.The data were processed qualitatively by the analysis of content (interviews and documents) and quantitatively by means of statistical tests that allowed inferences and adoption of frequencies. Among the key find ingests that the program is not standing as a structure supported by planning. The interests of the performers do not necessarily converge with the objectives of the Food Acquisition Program (PAA). A shockof goals was identified (within the same program) when comparingthe financial agent (Ministry of Rural Development and of Social Development and Fight Against Hunger Ministry r) and the executor, CONAB/RN. Within the assessed dimensions, the most fragileis the sub-managerial decision-making and Organizational Environment and internal assessment, still deserves attention the sizeof logistical and operational Subsystem, as this also proved weak.The focusin the quest toexpand thequantificationof the resultsof theFood Acquisition Program (PAA)by CONAB/RN does forget a quality management focused on what really should be:the compliance with the institutional objectives of the government program.Finally, the perspective for the traded implementation should be re-examined because excessive discretion by managers along with technical staff has characterized there al role of the Food Acquisition Program (PAA) as public policy. We conclude that the implementation model, which apparently aggregates values to the benefitted citizens, has weakened the context of work on family farms having the management model of the implementation process be reviewed by the Federal Government and point too ther paths, which have as a guide line the emancipation and developmentof the field or in the field andat the same time enables the reduction of nutritional deficiency of beneficiaries in a balanced and coherent way

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Neste estudo, foram examinadas as relações existentes entre a motivação e a satisfação do trabalhador no espaço laboral. O estudo empírico foi conduzido em uma única etapa, por meio da qual buscou-se conhecer as dimensões latentes identificadas e, a partir das dimensões validadas, buscou-se estabelecer relações com características motivacionais, como antecedentes, e satisfação pelo trabalho realizado, como conseqüência do atendimento das necessidades manifestadas pelo trabalhador. Foram entrevistados 38 (trinta e oito) funcionários da empresa Água Mineral Cristalina, incluindo-se os que ocupam cargos de chefia. Como instrumento de coleta de dados, foi utilizada parte do complexo da Auditoria do Sistema Humano ASH, criado por Quijano (1999), que se trata de um modelo de pesquisa na área de Psicologia Social, incluindo a Administração de Recursos Humanos, que analisa os processos psicológicos e psicossociais nas organizações. Para esta pesquisa, foram utilizados dois formulários sugeridos pelo autor citado, (anexos 01 e 02). O primeiro denomina-se condições para a motivação , com 15 (quinze) questões do tipo likert. O segundo, "trabalho bem feito e satisfação de necessidades", tem 22 (vinte e duas) questões, também do tipo likert. O instrumento foi respondido por colaboradores, independente da posição hierárquica, em aproximadamente 10 (dez) a 15 (quinze) minutos. A aplicação foi realizada diretamente pelo pesquisador nas unidades de produção e de administração da empresa. Por meio de modelagem de equações estruturais, foi estabelecido um modelo de relações causais entre as dimensões latentes relacionadas à motivação e o desempenho do empregado quando tem satisfeitas as suas necessidades. Quanto ao tratamento dos dados, este ocorreu de forma quantitativa. Quanto à análise, aconteceu após os dados terem sido tratados. Nesta pesquisa, os dados foram analisados por meio de estatísticas descritivas, atualizando-se os recursos de softwares específicos como Statistic ou SPSS Statistic Package for Social Sciences. Usou-se a técnica de Análise de Regressão, na qual foi utilizado o método STEPWISE que inclui na equação de explicação de uma variável dependente somente aquelas que auxiliam ou incrementam sua explicação. Como variáveis dependentes, foram utilizadas as variáveis do formulário "trabalho bem feito e satisfação de necessidades" e como variável independe as variáveis do questionário "condições para motivação". Sob o ponto de vista prático, este estudo mostrou que um determinado conjunto de características motivacionais influi positivamente na satisfação do trabalhador, que poderá realizar um trabalho bem feito; do lado teórico, a pesquisa verificou explicitamente a hipótese de que os aspectos motivacionais contribuem para que o empregado, sentindo-se satisfeito, desempenhe melhor as atribuições que lhe são conferidas

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In Brazil school food is constitutionally guaranteed to public school students at the preschool and elementary level. This food must be nutritious, hygienic and sanitary. The aim of the present study was to assess the hygienic/sanitary conditions of food and table utensil handlers in municipal public schools in Natal, Brazil. In total, 27 public schools were assessed, using a checklist and microbiological analysis of the hands and table utensils. For the microbiological analyses of the hands, coliforms were analyzed at 45ºC and for the utensils aerobic mesophilic bacteria, using methods recognized by AOAC, 2002 and APHA, 1992, respectively. Most of the schools studied did not exhibit good food and utensil handling practice procedures in any of the variables analyzed. It was shown that 74.1% of the handlers received no periodic training, 51.9% did not undergo annual health examinations and 100% did not practice proper hand hygiene, which reflected significantly (p < 0.05) in hand contamination, where fecal coliforms were detected on 55.6% of the hands analyzed. With respect to the utensils, it was found that 100% of the schools studied did not follow correct hygiene practices and most were classified as very bad ; that is, aerobic mesophilic bacteria values above the limits established by PAHO (Pan American Health Organization), with schools in the north and south districts recording the highest percentages. The results show that the hygienic-sanitary conditions of the food and utensil handlers in the schools studied were inadequate, demonstrating the need for implanting good handling practices aimed at protecting the health of children that take part in the program and offering safer foods. Researchers from the areas of food microbiology, nutrition, public health and statistics participated in this study, a decisive factor for characterizing it as multidisciplinary

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Introduction: Chagas Disease is a serious public health problem, with 5 million infected individuals in Brazil. Of these, approximately 30% develop chronic Chagas cardiomyopathy (CCC), where the main symptoms are fatigue and dyspnea. Objective: To correlate maximal exercise capacity with pulmonary function, inspiratory muscle strength and quality of life in patients with CCC. Methodology: Twelve individuals suffering from CCC were evaluated (7 men), with a mean age of 54.91± 8.60 years and the following inclusion criteria: functional class II and III according to the New York Heart Association (NYHA); left ventricle ejection fraction below 45%; clinical stability (> 3 months); symptom duration > 1 year, body mass index (BMI) < 35Kg/m2 and non-smokers or ex-smokers with a history of smoking <10 packs/day. All subjects were submitted to spirometry, manometer testing, maximal cardiopulmonary exercise testing (CPX) and a quality of life questionnaire (Minnesota). Results: A negative correlation was observed between VO2máx and MLHFQ scores (r=-0.626; p=0.03) and a positive association with MIP (r=0.713; p=0.009). Positive correlations were also recorded between MIP and spirometric variables [FEV1(r=0.825;p=0.001 ), FVC(r=0.66;p=0.01 and FEF25-75%(r=0.639;p=0.02)]. Conclusion: The present study demonstrated that in patients with CCC: VO2MAX is directly related to inspiratory muscle strength and quality of life, while deteriorating lung function is directly associated with respiratory muscle weakness

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There is no data about cardiac measurements em Brazilians obtained by CMR. This a muldisciplinary study with the objective of obtaining measurements of the left ventricle (LV) and right ventricle (RV) diastolic diameter (Dd), systolic diameter (Ds), diastolic volume (Dv), systolic volume (Sv), ejection fraction (EF) and myocardial mass in Brazilians. One hundred and seven (54 men and 53 women, mean age of 43.4 ± 13.1 years) asymptomatic individuals without heart disease were submitted to cardiac magnetic resonance (cMR) studies using steady state free precession technique. The means and standard deviations of the parameters of the LV and RV were respectively: LVDD = 4,8 ± 0,5 cm; LVSD = 3,0±0,6 cm; LVDV = 128,4±29,6 ml; LVSV = 45,2±16,6 ml; LVEF = 65,5±6,3%; LV mass = 95,2±30,8.1 g; RVDD = 3,9±1,3 cm; RVSD = 2,5±0,5 cm; RVDV = 126,5±30,7 ml; RVSV = 53.6±18,4 ml; RVEF = 58.3±8,0.0% and RV mass = 26,1±6,1 g. The masses and volumes were significantly higher in men, except for the LVSV. The RV EF was significantly higher in women. There was inverse correlation between RV systolic volume and with age, being more significant in men. This study describes for the first time benchmarks for cardiac measurements obtained by CMR among asymptomatic Brazilians individuals without heart disease and demonstrated differences according to sex and age

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The Nile tilapia, Oreochromis niloticus, is an important omnivorous fish in the reservoirs of the semi-arid region of Brazil. Throughout its growth tilapia s feeding behavior changes from a visual predator of zooplankton to a filter-feeder, collecting suspended particulate matter, including planktonic organisms, through pumping. This feature results in different impacts of tilapia on plankton community as the fish grows. Aiming to quantify the functional response of different sizes of Nile tilapia on zooplankton experiments in microcosms scale in the laboratory and in mesocosm scale in the field were carried out. The data were fitted to four different models of functional response. The best fits were obtained for nonlinear models in laboratory experiments. While the experiments in mesocosms were the best settings for responses of type I (juvenile and adult tilapia) and type III (fry). The Manly's alpha index was used to evaluate the feeding selectivity of tilapia on the three main groups of the zooplankton in the experiments in mesocosms. The results show that: (i) rotifers were the preferred prey of fingerlings,(ii) copepods were rejected by fry and juvenile tilapia and (iii) adult fish fed non-selectively on copepods, cladocerans and rotifers. The functional response models obtained in this research can be applied to population models and help in modeling the dynamics of interactions between Nile tilapia and the planktonic communities in the reservoirs of the semi-arid

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High levels of local, regional, and global extinctions has progressively simplified communities in terms of both species and ecosystem functioning. Theoretical models demonstrated that the degree of functional redundancy determines the rates of functional group loss in response to species extinctions. Here, we improve the theoretical predictions by incorporating in the model interactions between species and between functional groups. In this study, we tested the effect of different scenarios of interspecific interactions and effects between functional groups on the resistance to loss of community functional groups. Virtual communities have been built with different distribution patterns of species in functional groups, both with high and low evenness. A matrix A was created to represent the net effect of interspecific interactions among all species, representing nesting patterns, modularity, sensitive species, and dominant species. Moreover, a second matrix B was created to represent the interactions between functional groups, also exhibiting different patterns. The extinction probability of each species was calculated based on community species richness and by the intensity of the interspecific interactions that act upon it and group to which it belongs. In the model, successive extinctions decrease the community species richness, the degree of functional redundancy and, consequently, the number of functional groups that remain in the system. For each scenario of functional redundancy, A, and B, we ran 1000 simulations to generate an average functional extinction curve. Different model assumptions were able to generate remarkable variation on functional extinction curves. More extreme variations occurred when the matrix A and B caused a higher heterogeneity in the species extinction probability. Scenarios with sensitive species, positive or negative, showed a greater variation than the scenarios with dominant species. Nested interactions showed greater variation than scenarios where the interactions were in modules. Communities with maximal functional evenness can only be destabilized by the interactions between species and functional groups. In contrast, communities with low functional evenness can have its resistance either increased or decreased by the interactions. The concentration of positive interactions in low redundancy groups or negative interactions in high redundancy groups was able to decrease the functional extinction rates. In contrast, the concentration of negative interactions in low redundancy groups or positive interactions in high redundancy groups was able to increase the functional extinction rates. This model shows results that are relevant for species priorization in ecosystem conservation and restoration

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This study aimed to analyze the percentage of compliance, related to the requirements of Practice, achieved by 23 supermarkets in neighborhood after the deployment of Food Insurance Program. For its development research methodology adopted was the application start and end of a check-list (tool-specific SBP) in 23 supermarkets, target of this study. After the deployment of PAS was made a comparative study where it was possible to see that these companies need to improve conditions related to food safety, because according to the study, none of the 23 supermarkets evaluated met the criteria recommended by the SBP to 100% of compliance for the items critical of the check-list. Only 04 of the 23 supermarkets were in the range of 80 to 90% of the overall percentage of compliance, representing only 17.3% of the sample. Most of the sample submitted in a regular situation, according to the methodology of Cardoso (2001). Of the 23 supermarkets studied, 03 supermarkets were classified as poor (13.04%), 13 as scheduled (56.52%) as good and 07 (30.43%). You can see improvements in a small part of the sample, but the decline in the percentage of compliance of 02 companies after working for the implementation of the program, showing lack of responsibility and commitment of companies which should have as its top priority to food safety that market

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The thesis argues the importance of the logistic management for the performance of the companies and for the foreign trade. The study is endorsed in construction of one analyses that brings in its essential the underlyng elements for the understanding of the subject. The analyse made from the data of an exporters company of Rio Grande of the Norte, with performance in the branch of candies, allowed to evaluate an efficient of the logistic management, that involving operacional and financial questions, is unavoidable for reduction of costs of the companies and has significant impact is its profitability