Utilização de matérias primas vegetais para aplicabilidade como inibidores de corrosão

In the search for products that act as corrosion inhibitors and do not cause environmental, impact the use of plant extracts as corrosion inhibitors is becoming a promising alternative. In this work the efficiency of polar extracts (ethanol extracts) obtained from the plants Anacardium occidentale Linn (AO) and Phyllantus amarus Schum. & Thonn (PA) as corrosion inhibitors were evaluated in different concentrations. For that AO and PA extracts were solubilized in the microemulsion systems (SME) containing saponified coconut oil as surfactant (SME -OCS and SME-OCS-1) in saline (NaCl 3,5 %) solution, which was also used as electrolyte. Both SME-OCS and SME-OCS-1 were characterized by surface tension and viscosity methods showing a Newtonian fluid behavior. The SME-OCS and SME-OCS-1 systems satisfactorily solubilized the polar extracts AO and PA with measurements carried out by ultraviolet spectroscopy. The measurements of corrosion inhibition efficiencies were performed by the electrochemical linear polarization resistance (LPR) technique as well as weight loss, on the surface of AISI 1020 carbon steel. The maximum corrosion inhibition efficiencies were determined by extrapolation of Tafel plots, showing the following values: 95,6 % for the system SME-OCS-AO, 98,9 % for the system SME-OCS-AO-1 and 93,4 % for the system SME-OCS-PA

Avaliação da atividade antimalárica de extratos obtidos de algas marinhas no litoral do Rio Grande do Norte

Malaria is a major parasitic disease worldwide, accounting for about 500 million cases and causing 2 million to 3 million deaths annually. Four species are responsible for transmitting this disease to humans: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae and Plasmodium ovale. The parasite resistance to antimalarial drugs and the usual limitations of the vector control implications are contributing to the spread of the disease. The most of significant advances in the search for new antimalarial drugs is based on natural components, the main ones being currently used antimalarial drugs derived from plants. Research on natural products of marine origin (particularly algae) show that some species possess antiplasmodial activity. Knowing that the coast of Rio Grande do Norte is home to several species of algae, the present study was to evaluate, for the first time, the antimalarial activity of ethanolic extracts of seaweed Spatoglossum schroederi, Gracilaria birdiae and Udotea flabellum against Plasmodium falciparum 3D7 strain tests and in vitro using the murine model (Plasmodium berghei) for evaluation in vivo. These species were ground, macerated with ethanol for 24 hours and the extracts concentrated in rotaevaporador (45 ° C ± 5 ° C). For in vitro tests, the extracts were diluted and tested at concentrations between 100 and 1.56 μg/ml (seven concentrations in triplicate), in order to obtain IC50 of each extract. The cytotoxicity tests with macrophages and BGM were performed using the MTT colorimetric assay. BGM macrophages and cells were distributed in 96 wells per plate (1x 105 to macrophages and 1x104 cells per well for BGM) and incubated for 24h at 37 ° C. The ethanol extracts were diluted and tested at concentrations of 100 to 1,56 μg/ml (seven concentrations in triplicate). After periods of 24 hours of incubation with the extracts, 100 μg of MTT was added to each well, and 3 hours elapsed, the supernatant was removed and added 200 μl of DMSO in each well. The absorbance of each well was obtained by reading on a spectrophotometer at 570 nm filter. To evaluate the acute toxicity in vivo, Swiss mice received a single dose (oral) 2000 mg/kg/animal of each extract tested. The parameters of acute toxicity were observed for 8 days. For in vivo tests, Swiss mice were inoculated with 1x105 erythrocytes infected with P. berghei. The treatment was given first to fourth day after infection with 0.2 ml of the extracts in doses of 1000 and 500 mg//g animal. The negative control group received 0.2 ml of 2% Tween-20, whereas the positive control group received sub-dose of chloroquine (5 mg/kg/animal). The assessment of antimalarial activity was done by suppressing suppressing the parasitemia at 5 and 7 days after infection. The growth inhibition of parasites was determined relative to negative control (% inhibition = parasitaemia in control - parasitemia in sample / parasitemia control x 100), the mortality of animals was monitored daily for 30 days The results showed that algae Spatoglossum schroederi and Udotea flabellum showed antimalarial activity in vitro, with reduced parasitemia of 70.54% and 54, respectively. The extracts of the three algae tested showed moderate to high cytotoxicity. Algae S. schroederi and U. flabellum were active against P. berghei only at doses of 500 mg / kg with reduction ranging from 54.58 to 52.65% for the fifth day and from 32.24 to 47.34% for the seventh day, respectively. No toxicity was observed in vivo at the dose tested, over the 8 days of observation. Although preliminary data, the bioactive components in those possible seaweed may be promising for the development of new anti-malarial drugs

Avaliação de um método de cromatografia em fase gasosa head space e estudo da estabilidade do etanol em amostras de sangue

The ethanol is the most overused psychoactive drug over the world; this fact makes it one of the main substances required in toxicological exams nowadays. The development of an analytical method, adaptation or implementation of a method known, involves a process of validation that estimates its efficiency in the laboratory routine and credibility of the method. The stability is defined as the ability of the sample of material to keep the initial value of a quantitative measure for a defined period within specific limits when stored under defined conditions. This study aimed to evaluate the method of Gas chromatography and study the stability of ethanol in blood samples, considering the variables time and temperature of storage, and the presence of preservative and, with that check if the conditions of conservation and storage used in this study maintain the quality of the sample and preserve the originally amount of analyte present. Blood samples were collected from 10 volunteers to evaluate the method and to study the stability of ethanol. For the evaluation of the method, part of the samples was added to known concentrations of ethanol. In the study of stability, the other side of the pool of blood was placed in two containers: one containing the preservative sodium fluoride 1% and the anticoagulant heparin and the other only heparin, was added ethanol at a concentration of 0.6 g/L, fractionated in two bottles, one being stored at 4ºC (refrigerator) and another at -20ºC (freezer), the tests were performed on the same day (time zero) and after 1, 3, 7, 14, 30 and 60 days of storage. The assessment found the difference in results during storage in relation to time zero. It used the technique of headspace associated with gas chromatography with the FID and capillary column with stationary phase of polyethylene. The best analysis of chromatographic conditions were: temperature of 50ºC (column), 150ºC (jet) and 250ºC (detector), with retention time for ethanol from 9.107 ± 0.026 and the tercbutanol (internal standard) of 8.170 ± 0.081 minutes, the ethanol being separated properly from acetaldehyde, acetone, methanol and 2-propanol, which are potential interfering in the determination of ethanol. The technique showed linearity in the concentration range of 0.01 and 3.2 g/L (0.8051 x + y = 0.6196; r2 = 0.999). The calibration curve showed the following equation of the line: y = x 0.7542 + 0.6545, with a linear correlation coefficient equal to 0.996. The average recovery was 100.2%, the coefficients of variation of accuracy and inter intra test showed values of up to 7.3%, the limit of detection and quantification was 0.01 g/L and showed coefficient of variation within the allowed. The analytical method evaluated in this study proved to be fast, efficient and practical, given the objective of this work satisfactorily. The study of stability has less than 20% difference in the response obtained under the conditions of storage and stipulated period, compared with the response obtained at time zero and at the significance level of 5%, no statistical difference in the concentration of ethanol was observed between analysis. The results reinforce the reliability of the method of gas chromatography and blood samples in search of ethanol, either in the toxicological, forensic, social or clinic

Alcoolemia em vítimas fatais de acidentes de trânsito no Rio Grande do Norte empregando cromatografia em fase gasosa - head space

Alcohol is one of the few psychotropic drugs that their consumption has admitted legally and sometimes encouraged by the society. Studies show alcohol as the highest consumption of drugs among young people and society in general, probably because of its availability and easy access. The abuse causes public health problems, which was closely related to the violence, socioeconomic problems and the high number of automobile accidents. Transit is one of the main sectors affected by the effects of alcohol, observing a high incidence in the studies. About half of automobile accidents occurs after the consumption of alcoholic beverage, and the vast majority of cases related to high concentrations of alcohol in the bloodstream. The relationship of drunk with traffic accidents is in fact evident everywhere in the world, including Brazil, where studies have shown a high relationship between alcohol consumption and traffic accidents. This study determined the alcohol in fatal victims of traffic accidents in the state of Rio Grande do Norte and established the profile of this population compared with those found in Brazil and other countries. Samples of blood of ethanol added to fulfillment of the standardization of chromatographic conditions and procedures for the analysis, being employed in the determination of alcohol in blood samples of 277 victims of traffic accidents, collected at the Institute of Scientific Technical Police of Rio Grande do North (ITEP) in the year 2007. The blood alcohol level was determined in these samples correlated with the sex, age and marital status of the victim and the location, day of week and month when the accident occurred, is doing a statistical analysis and outlining a profile of the victims of an accident at transit in the state of Rio Grande do Norte. The parameters of standardization studied ensured the quality of the analytical method and, consequently, to obtain reliable laboratory results. Being given the best temperature for injector (150 ºC), detector (250 ºC) and column (50 ºC) with a flow of gas in the column of 2mL/minutos and analysis of time of 12 minutes. The method was linear in the range of 0.01 to 3.2 g / L (r2 = 0.9989) with average recovery of 100.2% and precision with coefficient of variation less than 15%. The analysis carried out on victims of fatal road traffic accidents, ethanol detected in the blood in 66.43% of the victims and these, 96% showed concentration ≥ 0.2 g / L, 87.73% of victims were male, while 12.27% female. The younger age group (1535 years) was the most involved (52,35%) and most single (55.60%). The accidents occurred with greater prevalence in the day on Monday (27%) followed by Sunday (24,19%) and Saturday (15,52%) and it was found that the prevalence of injuries varied between the different months of the year, and in February (14.4%) and April (10.47%) the months that had a higher number of accidents, however this oscillation showed no statistically significant difference. Also no significant difference was observed between the tracks of concentration found in men and women. The standardized method showed to be efficient, given satisfactorily to the goals of this work, and the high levels of alcohol found in victims of fatal road traffic accidents are consistent with several studies of literature, and the profile of the victim also supported by presenting in its most young adults, male and single

Fermentação alcoólica utilizando líquido da casca de coco verde como fonte de nutrientes

The liquid of the rind of green coconut (LCCV), an effluent stream from the industrial processing of green coconut rind, is rich in sugars and is a suitable feedstock for fermentation. The first step of this study was to evaluate the potential of natural fermentation of LCCV. As the literature did not provide any information about LCCV and due to the difficulty of working with such an organic effluent, the second step was to characterize the LCCV and to develop a synthetic medium to explore its potential as a bioprocess diluent. The third step was to evaluate the influence of initial condensed and hydrolysable tannins on alcoholic fermentation. The last step of this work was divided into several stages: in particular to evaluate (1) the influence of the inoculum, temperature and agitation on the fermentation process, (2) the carbon source and the use of LCCV as diluent, (3) the differences between natural and synthetic fermentation of LCCV, in order to determine the best process conditions. Characterization of LCCV included analyses of the physico-chemical properties as well as the content of DQO, DBO and series of solids. Fermentation was carried out in bench-scale bioreactors using Saccharomyces cerevisiae as inoculum, at a working volume of 5L and using 0.30% of soy oil as antifoam. During fermentations, the effects of different initial sugars concentrations (10 - 20%), yeast concentrations (5 and 7.5%), temperatures (30 - 50°C) and agitation rates (400 and 500 rpm) on pH/sugars profiles and ethanol production were evaluated. The characterization of LCCV demonstrated the complexity and variability of the liquid. The best conditions for ethanol conversion were (1) media containing 15% of sugar; (2) 7.5% yeast inoculum; (3) temperature set point of 40°C and (4) an agitation rate of 500 rpm, which resulted in an ethanol conversion rate of 98% after 6 hours of process. A statistical comparison of results from natural and synthetic fermentation of LCCV showed that both processes are similar

Tratamento de materiais contaminados com bifenilas policloradas (PCBS) via extração convencional e fluído supercrítico

The decontamination of the materials has been subject of some studies. One of the factors that it increases the pollution is the lack of responsibility in the discarding of toxic trash, as for example the presence of PCB (Polychlorinated Biphenyls) in the environment. In the Brazilian regulations, the material contaminated with PCB in concentrations higher than 50 ppm must be stored in special places or destroyed, usually by incineration in plasma furnace with dual steps. Due to high cost of the procedure, new methodologies of PCBs removal has been studied. The objective of this study was to develop an experimental methodology and analytical methodology for quantification of removal of PCBs through out the processes of extractions using supercritical fluid and Soxhlet method, also technical efficiency of the two processes of extraction, in the treatment of contaminated materials with PCBs. The materials studied were soils and wood, both were simulated contamination with concentration of 6.000, 33.000 and 60.000 mg of PCB/ kg of materials. Soxhlet extractions were performed using 100 ml of hexane, and temperature of 180 ºC. Extractions by fluid supercritical were performed at conditions of 200 bar, 70°C, and supercritical CO2 flow-rate of 3 g/min for 1-3 hours. The extracts obtained were quantified using Gas chromatography-mass spectrometry (GC/MS). The conventional extractions were made according to factorial experimental planning technique 22, with aim of study the influence of two variables of process extraction for the Soxhlet method: contaminant concentration and extraction time for obtain a maximum removal of PCB in the materials. The extractions for Soxhlet method were efficient for extraction of PCBs in soil and wood in both solvent studied (hexane and ethanol). In the experimental extraction in soils, the better efficient of removal of PCBs using ethanol as solvent was 81.3% than 95% for the extraction using hexane as solvent, for equal time of extraction. The results of the extraction with wood showed statistically it that there is not difference between the extractions in both solvent studied. The supercritical fluid extraction in the conditions studied showed better efficiency in the extraction of PCBs in the wood matrix than in soil, for two hours extractions the obtain percentual of 43.9 ± 0.5 % for the total of PCBs extracted in the soils against 95.1 ± 0,5% for the total of PCBs extracted in the wood. The results demonstrated that the extractions were satisfactory for both technical studied

Formação de particulas submicrometricas de pmma por cristalização termica de solução polimérica

Polymer particles in the nanometer range are of fundamental interest today, especially when used as carrier systems in the controlled release of drugs, cosmetics and nutraceuticals, as well as in coating materials with magnetic properties. The main objective of the present study concerns the production of submicron particles of poly (methyl methacrylate) (PMMA) by crystallization of a polymer solution by thermally controlled cooling. In this work, PMMA solutions in ethanol and 1-propanol were prepared at different concentrations (1% to 5% by weight) and crystallized at different cooling rates (0.2 to 0.8 ° C / min) controlled linearly. Analysis of particle size distribution (DLS / CILAS) and scanning electron microscopy (SEM) were performed in order to evaluate the morphological characteristics of the produced particles. The results demonstrated that it is possible to obtain submicron polymer perfectly spherical particles using the technique discussed in this study. It was also observed that, depending on the cooling rate and the concentration of the polymer solution, it is possible to achieve high yield in the formation of submicron particles. In addition, preliminary tests were performed in order to verify the ability of this technique to form particulated carrier material with magnetic properties. The results showed that the developed technique can be an interesting alternative to obtain polymer particles with magnetic properties

Produção de bioetanol a partir de pedúnculo de caju (Anacardium occidentale L.) por fermentação submersa

Recently, global demand for ethanol fuel has expanded very rapidly, and this should further increase in the near future, almost all ethanol fuel is produced by fermentation of sucrose or glucose in Brazil and produced by corn in the USA, but these raw materials will not be enough to satisfy international demand. The aim of this work was studied the ethanol production from cashew apple juice. A commercial strain of Saccharomyces cerevisiae was used for the production of ethanol by fermentation of cashew apple juice. Growth kinetics and ethanol productivity were calculated for batch fermentation with different initial sugar (glucose + fructose) concentration (from 24.4 to 103.1 g.L-1). Maximal ethanol, cell and glycerol concentrations (44.4 g.L-1, 17.17 g.L-1, 6.4 g.L-1, respectively) were obtained when 103.1 g.L-1 of initial sugar concentration were used, respectively. Ethanol yield (YP/S) was calculated as 0.49 g (g glucose + fructose)-1. Pretreatment of cashew apple bagasse (CAB) with dilute sulfuric acid was investigated and evaluated some factors such as sulfuric acid concentration, solid concentration and time of pretreatment at 121°C. The maximum glucose yield (162.9 mg/gCAB) was obtained by the hydrolysis with H2SO4 0.6 mol.L-1 at 121°C for 15 min. Hydrolysate, containing 16 ± 2.0 g.L-1 of glucose, was used as fermentation medium for ethanol production by S. cerevisiae and obtained a ethanol concentration of 10.0 g.L-1 after 4 with a yield and productivity of 0.48 g (g glucose)-1 and 1.43 g.L-1.h-1, respectively. The enzymatic hydrolysis of cashew apple bagasse treated with diluted acid (CAB-H) and alkali (CAB-OH) was studied and to evaluate its fermentation to ethanol using S. cerevisiae. Glucose conversion of 82 ± 2 mg per g CAB-H and 730 ± 20 mg per g CAB-OH was obtained when was used 2% (w/v) of solid and loading enzymatic of 30 FPU/g bagasse at 45 °C. Ethanol concentration and productivity was achieved of 20.0 ± 0.2 g.L-1 and 3.33 g.L-1.h-1, respectively when using CAB-OH hydrolyzate (initial glucose concentration of 52.4 g.L-1). For CAB-H hydrolyzate (initial glucose concentration of 17.4 g.L-1), ethanol concentration and productivity was 8.2 ± 0.1 g.L-1 and 2.7 g.L-1.h-1, respectively. Hydrolyzates fermentation resulted in an ethanol yield of 0.38 g/g glucose and 0.47 g/g glucose, with pretreated CABOH and CAB-H, respectively. The potential of cashew apple bagasse as a source of sugars for ethanol production by Kluyveromyces marxianus CE025 was evaluated too in this work. First, the yeast CE025 was preliminary cultivated in a synthetic medium containing glucose and xylose. Results showed that it was able to produce ethanol and xylitol at pH 4.5. Next, cashew apple bagasse hydrolysate (CABH) was prepared by a diluted sulfuric acid pre-treatment. The fermentation of CABH was conducted at pH 4.5 in a batch-reactor, and only ethanol was produced by K. marxianus CE025. The influence of the temperature in the kinetic parameters was evaluated and best results of ethanol production (12.36 ± 0.06 g.L-1) was achieved at 30 ºC, which is also the optimum temperature for the formation of biomass and the ethanol with a volumetric production rate of 0.25 ± 0.01 g.L-1.h-1 and an ethanol yield of 0.42 ± 0.01 g/g glucose. The results of this study point out the potential of the cashew apple bagasse hydrolysate as a new source of sugars to produce ethanol by S. cerevisiae and K. marxianus CE025. With these results, conclude that the use of cashew apple juice and cashew apple bagasse as substrate for ethanol production will bring economic benefits to the process, because it is a low cost substrate and also solve a disposal problem, adding value to the chain and cashew nut production

Álcool e comportamento: efeitos na aprendizagem e memória

Excessive alcohol consumption is responsible for many harmful effects on individuals and society. Despite years of research, the mechanisms by which alcohol affects neurological functions and the exact causes of cognitive impairment related to long-term use are unknown. In this sense, this master study proposed to observe how different doses of alcohol affect the addiction response and the learning ability of two fish species: Betta splendens and Danio rerio, the latter a commonly model due to organizational and functional characteristics shared with mammals. For this, different concentrations of ethanol (0%, 0.1%, 0.25%, 1% and 1.5%) were used in acute, chronic and withdrawal treatments. We tested the fish in three experimental protocols: 1) alcohol addiction potential using conditioned place preference, 2) associative conditioning using light as unconditioned stimulus and food as conditioned stimulus and 3) spatial learning using a maze without cues. For the alcohol addiction potential, preference between two different places in a shuttle box was tested before and after alcohol exposure (chronic and acute). In this test, the animals intoxicated by 0.1% did not change behavior, while animals receiving 1% and 1.5% alcohol changed the initial preference to the side where they received alcohol For the associative conditioning, the results show that the groups undergoing low dose (0.1%), both in chronic and withdrawal treatment, learned the task faster than control; groups under 0.25 and 1% alcohol withdrawal learned the task after control; groups chronically intoxicated with these doses did not learn the task. For the spatial learning test, fish submitted to acute and chronic treatments decreased the time to exit the maze; there were significant differences in the animal s performance in a dose-dependent pattern. This difference was not observed for the withdrawal treatment. Given these results, we conclude that the effects of alcohol on learning are dependent on the dosage. Furthermore, low doses of alcohol seem to maximize animal performance on learning tasks and do not alter their seeking behavior, while higher doses induced addition and hinder learning

Análises bromatológicas e fitoquímicas de frutos de Licania tomentosa (Benth) FRITSCH

This study conducted chemical analyzes of the fruits of Licania tomentosa Benth belonging to the Chrysobalanaceae family, order and superorder Rosiflorae Rosales. Samples were collected in February 2011 in the city of Natal - RN. The fruits were separated into peel, pulp and seed, and the samples were analyzed on moisture and ash by thermogravimetric methods, reducing and total sugars, lipids by Soxhlet extraction, minerals by ICP / OES and other analyzes by physical measurements of the fruit. The fruits for the analysis of determination of flavonoids and phenolic compounds were dried at 40 ° C and ground. For the analyzes to determine the content of phenolics and flavonols was used spectroscopy in the visible region, and also performed the characterization of ethanol extracts by high performance liquid chromatography and test for antioxidant activity hydroethanolic extracts. The results obtained are about 83.9% of the fruits have a length between 4.0 to 6.0 cm with respect to the diameter of the fruit about 97.4% of the fruits have a diameter between 2.0 - 4, 0 cm, mean weight of 36.14 g (7.86), the bark showed 60.5 (1.5)% relative humidity, the flesh 72.3 (0.9) and 44.4 seeds (0.4 )%, the bark showed 0.22 (0.00)% ash, the pulp 1.41 (0.01)% and the seed 1.18 (0.01)%, the bark showed 3.73 (0, 09) mg lipids / 100 g sample of the pulp 0.40 (0.04) and the seed 0.05 (0.00). With respect to reducing sugars and total gave the results, 16.23 (0.23) g/100g and 20.70 (0.24) g/100g. The fruit is presented with a good source of nutrients especially carbohydrates and lipids. The analysis for determining the antioxidant activity tests were performed reducing power and antioxidant capacity, the antioxidant capacity of hydroethanolic extracts of peel and pulp showed similar results, with higher concentrations however hydroethanolic bark extract. Regarding the content of phenolics and flavonoids hidroetanílico bark extract showed higher concentration values. The characterization of the extracts by high performance liquid chromatography identified the following compounds by retention time indicated by the race of the standards: galic acid, kaempferol and kaempferol derivatives. Considering the results of the fruit Licania tomentosa Benth may be an alternative food by analysis of their nutritional content and has substances with antioxidant action