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Hovenia dulcis is a plant commonly used as a pharmaceutical supplement, having displayed important pharmacological properties such antigiardic, antineoplastic and hepatoprotective. The purpose of this work was investigate the cytotoxic, genotoxic and mutagenic potential from fractions of Hovenia dulcis ethanolic extract on Saccharomyces cerevisiae strains FF18733 (wild type) and CD138 (ogg1). Ethanolic extract from Hovenia dulcis leaves was fractioned using organic solvents according to increasing polarity: Hexane (1:1), dichlorometane (1:1), ethyl acetate (1:1) and butanol (1:1). Three experimental assays were performed, such as (i) inactivation of cultures; (ii) mutagenesis (canavanine resistance system) and (iii) loss of mitochondrial function (petites colonies). The findings shown a decrease in cell viability in FF18733 and CD138 strains; all fractions of the extract were mutagenic in CD138 strain; only ethyl acetate and butanol fractions increased the rate of petites colonies for CD138 strains. Ethyl acetate and n-butanol fractions induces mutagenicity, at the evaluated concentrations, in mitochondrial and genomic DNA in CD138 strain, mediated by oxidative lesions. In conclusion, it is possible to infer that the lesions caused by the extract fractions could be mediated by reactive oxygen species and might reach multiple molecular targets to cause cellular damage.

This study was conducted to evaluate the effect of addition of gallic acid as the single antioxidant to the base medium for in vitro culture of sheep secondary follicles and if the phosphatidylinositol 3-kinase (PI3K) pathway is involved in the action of gallic acid. Secondary follicles were isolated and cultured for 12 days in α-MEM supplemented with bovine serum albumin (BSA), insulin, glutamine, hypoxanthine, transferrin, selenium, and ascorbic acid (control medium: α-MEM+) or in α-MEM supplemented with BSA, insulin, glutamine, hypoxanthine and different concentrations of gallic acid (25, 50 or 100 μM), thus replacing transferrin, selenium and ascorbic acid in the medium. Follicle morphology, glutathione (GSH), and mitochondrial activity, and meiotic resumption were evaluated. Furthermore, inhibition of PI3K pathway was performed by pretreatment with LY294002. After 12 days of culture, the follicle survival in a medium containing 100 μM gallic acid was similar (P > 0.05) to α-MEM+ and greater (P

Ethanol production in Brazil has two major drawbacks, related to the maximum product concentration and control of the process temperature. During the fermentation, yeast metabolism completely ceases when the ethanol concentration reaches 95 g.L−1, while high temperatures increase both the risk of bacterial contamination and the sensitivity of the yeast to ethanol toxicity. In order to address these problems, extractive ethanol fermentation with carbon dioxide stripping offers a way to overcome the toxic effect of ethanol on yeast cell growth, while also avoiding increase of the broth temperature during the fermentation. Although ethanol removal by gas stripping has a positive effect on ethanol volumetric productivity, the application of this technique for economization of cooling water during the ethanol fermentation process requires a technical analysis. Therefore, in the present work, evaluation was made of heat removal from the culture broth during extractive fermentation with ethanol stripping by CO2. First, ethanol fermentations were carried out using a 10-L bench-scale bubble column bioreactor. The mass and energy balances were used to obtain kinetic parameters, with the heat generated during fermentation being close to theoretical values. Extractive batch fermentations were performed using two carbon dioxide specific flow rates (0.5 and 1.0 vvm), resulting in efficient removal of heat from the fermentation broth, as well as reducing cooling water consumption by up to 62.7%. These results were then validated in a pilot-scale (100-L) extractive fed-batch fermentation performed at 1.0 vvm, resulting in a 63.1% reduction of cooling water consumption. In an industrial distillery, this lower consumption of cooling water would allow substantial savings of chemicals needed for cooling water treatment, making the ethanol production process in Brazil more competitive in the near future.

The aim of the present work was to evaluate the ability of a portable near-infrared (NIR) spectrometer to detect adulteration in ground meat. NIR spectroscopy has been used in food science for 40 years. Miniaturization, however, is a recent approach that allows in situ analysis. In this study, samples of meat were adulterated in the range of 0–100 wt% in binary blends (chicken/beef; beef/pork; pork/chicken) and ternary blends (beef/chicken/pork). For the binary blends, values of R2c and R2p ranged from 0.78 to 0.99. Optimal results were achieved to predict the chicken content in beef blends (R2c = 0.98; R2p = 0.99; RMSEC = 4.5 wt%; RMSEP =3.5 wt%; LOD = 3.4 wt% and LOQ 11.2 wt%). For the ternary blends, the analytical performance was considered to be good only for the prediction of beef content, with the following values: R2c = 0.98, R2p = 0.93, RMSEC = 3.6 wt%, RMSEP =4.7 wt%, LOD =4.7 wt% and LOQ 15.7 wt%. Finally, in order to improve the analytical performance of the regression models developed thus far, the NIR spectra of the binary and ternary blends were grouped into a unique matrix. PLS and SVR regression models were constructed, and the SVR model resulted in performance parameters superior to the PLS. Nevertheless, the portable NIR spectrometer showed satisfactory performance for the quantification of beef in ground meat blends (chicken/beef, pork/beef, and chicken/beef/pork).

Despite being well established, a major limitation remains in ethanol fermentation processes: the presence of ethanol inhibits yeast activity, affecting the cell growth rate and, consequently, the ethanol production rate. For this reason, low ethanol concentrations of around 8–9% v/v are reached at the end of the fermentation, hence requiring the consumption of a significant amount of energy for recovery of the fermentation product, while generating large amounts of vinasse. This situation requires the use of large fermentation tanks in order to achieve satisfactory ethanol production. Additionally, due to the large amount of heat generated by the fermentation processes, the temperature control of industrial fermentation tanks is a great challenge in tropical regions such as Brazil. The goal of the present study was to analyze the influence of operating variables on the performance of ethanol stripping at bench and pilot scales, using carbon dioxide as the carrier gas, and to propose a model describing the changes in ethanol mass and solution temperature during the stripping process. Bench scale experiments were conducted using a 5-L bubble column filled with 10% v/v hydroalcoholic solution, and the pilot scale experiments were performed using a 95-L column filled with industrial fermented wine without yeast. A factorial design was applied to identify the most important operating variables for the following stripping performance parameters: entrainment factor, concentration factor, and temperature reduction factor. The results showed that both temperature and entrainment factor were positively influenced by initial solution temperature and specific CO2 flow rate, and negatively affected by height-to-diameter ratio. The temperature of the carbon dioxide did not affect either of these performance parameters. The simulation results revealed that the stripping model accurately described the decreases in ethanol mass and solution temperature during the stripping operation, with good agreement between the experimental and simulated data, and errors less than 5% in most cases.

The persistent organic pollutants (POPs), such as organochlorine pesticides and PCBs, are ordinarily monitored in the aquatic environment or in soil in the environmental quality monitoring programs in Sao Paulo, Brazil. One of the core matrices proposed in the POPs Global Monitoring Plan (GMP) from the Stockholm Convention list is the ambient air, which is not a usual matrix for POPs monitoring in the country. In this study POP levels were evaluated in the air samples from an urban site in Sao Paulo City over five years, starting in 2010 as a capacity building project for Latin America and the Caribbean region for POP monitoring in ambient air using passive samplers. Furthermore, after the end of the Project in 2012, the monitoring continued in the same sampling site as means to improving the analytical capacity building and contribute to the GMP data. The POPs monitored were 17 congeners of 2,3,7,8 chloro-substituted PCDDs and PCDFs, dioxin-like PCBs, indicator PCBs, organochlorine pesticides and toxaphene. The results show a slight decrease in PCDD/F, dl-PCBs and indicator PCBs levels along the five years. The organochlorine pesticide endosulfan was present at its highest concentration at the beginning of the monitoring period, but it was below detection level in the last year of the monitoring. Some other organochlorine pesticides were detected close to or below quantitation limits. The compounds identified were dieldrin, chlordane, α-HCH, γ-HCH, heptachlor, heptachlor epoxide, hexachlorobenzene and DDTs. Toxaphene congeners were not detected. These results have confirmed the efficacy of passive sampling for POP monitoring and the capacity building for POP analysis and monitoring was established. However more needs to be done, including expansion of sampling sites, new POPs and studies on sampling rates to be considered in calculating the concentration of POPs in ambient air using a passive sampler.

It was demonstrated that tin, as stannous chloride (SnCl(2)), can facilitate the neuromuscular transmission by accelerating the transmitter release from the nerve terminals in the mouse. When this salt is injected into laboratory animals, it can produce stimulation or depression of the central nervous system. Because calcium (Ca(2+)) influx into the cytoplasm is indispensable to release the transmitter, it would be possible that SnCl(2) increases the Ca(2+) influx at the nerve terminals but not by blocking the K(+) channels. SnCl(2) is known to inhibit the immune response in rodents and to induce tumor generation in thyroid gland. There is no general agreement regarding its genotoxicity and it was discussed that the effects of this salt might depend on the physicochemical conditions and the route of its administration. SnCl(2) has been used in many sectors of human interest, such as food industry and nuclear medicine. This salt is directly administered to human beings endovenously, when it is used as a reducing agent to prepare 99mTc-radiopharmaceuticals which are also used for cerebral studies. SnCl(2) is capable to promote the generation of reactive oxygen species (ROS) that are responsible for the oxidative stress. Oxidative stress has been related with aging and other neurological diseases. So, it is relevant to evaluate other biological effects of SnCl(2). We decided to study these effects using Escherichia coli mutant strains, deficient in DNA repair genes, and supercoiled plasmid DNA. We evaluated the influence of medicinal plants, metal chelating agents, and ROS scavengers against the SnCl(2) deleterious effects. Our results show that SnCl(2) produced lesions in vitro as well as in vivo. This inactivation may be due to the production of ROS. We observed that the genotoxic effect of SnCl(2) was partly inhibited or disappeared, when the treatments were done in the presence of medicinal plants, metal chelating agents, and ROS scavengers. In conclusion, these findings suggest that the SnCl(2) biological effects may be associated with the generation of ROS. Moreover, we can speculate that ROS could be associated with the detrimental effects in the brain due to exogenous or endogenous metals.

Cassia angustifolia Vahl. (senna) is commonly used in self-medication and is frequently used to treat intestine constipation. A previous study involving bacteria and plasmid DNA suggested the possible toxicity of the aqueous extract of senna (SAE). The aim of this study was to extend the knowledge concerning SAE genotoxicity mechanisms because of its widespread use and its risks to human health. We investigated the impact of SAE on nuclear DNA and on the stability of mitochondrial DNA in Saccharomyces cerevisiae (wt, ogg1, msh6, and ogg1msh6) strains, monitoring the formation of petite mutants. Our results demonstrated that SAE specifically increased Can(R) mutagenesis only in the msh6 mutant, supporting the view that SAE can induce misincorporation errors in DNA. We observed a significant increase in the frequency of petite colonies in all studied strains. Our data indicate that SAE has genotoxic activity towards both mitochondrial and nuclear DNA.

Papain, a phytotherapeutic agent, has been used in the treatment of eschars and as a debriding chemical agent to remove damaged or necrotic tissue of pressure ulcers and gangrene. Its benefits in these treatments are deemed effective, since more than 5000 patients, at the public university hospital at Rio de Janeiro, Brazil, have undergone papain treatment and presented satisfactory results. Despite its extensive use, there is little information about toxic and mutagenic properties of papain. This work evaluated the toxic and mutagenic potential of papain and its potential antioxidant activity against induced-H2O2oxidative stress inEscherichia colistrains. Cytotoxicity assay, Growth inhibition test, WP2-Mutoxitest and Plasmid-DNA treatment, and agarose gel electrophoresis were used to investigate if papain would present any toxic or mutagenic potential as well as if papain would display antioxidant properties. Papain exhibited negative results for all tests. This agent presented an activity protecting cells againstH2O2-induced mutagenesis.

It was recently discovered that exposure to small concentrations of the essential oils of sweet fennel (Foeniculum vulgare Mill) or pignut [Hyptis suaveolens (L.) Poit] can be used to control aphids. What is not known is whether these oils also influence honeybee behavior. Experiments using both harnessed and free-flying foragers at concentrations used to control aphids showed that bees readily associated the odors with a reward, discriminated between them, and were not repelled. Honeybees, however, would not consume the oils when mixed with sucrose to create an unconditioned stimulus. An experiment in which harnessed bees consumed various concentrations showed that concentrations greater than 50% were detrimental. The experiments reported here provide further evidence supporting the use of conditioning techniques to evaluate the use of essential oils on honey bee behavior.

Mesoporous SBA-15 impregnated with tetrapropylammonium hydroxide and sodium aluminate was crystallized in glycerol containing different amounts of water (0 – 40 weight %). Under these conditions crystallization in glycerol containing at least 30 weight % of water leads to ZSM-5 as discrete particles. No formation of ZSM-5 or ZSM-5 precursors was observed after secondary crystallization of SBA-15 in glycerol with water contents of 15 weight % or lower.

Micro/mesostructured ZSM-5/SBA-15 composites were prepared by secondary crystallisation of SBA-15 impregnated with a solution of tetrapropylammonium hydroxide and sodium aluminate. The samples were characterised by X-ray diffraction (XRD), nitrogen sorption, infrared spectroscopy (FTIR) and scanning electronic microscopy (SEM). XRD and nitrogen sorption confirmed the partial preservation of the mesoporous structure and the formation of ZSM-5. Formation of ZSM-5 structural units in still X-ray amorphous material was detected by FTIR, which further indicates the incorporation of aluminium into the ZSM-5 structure. However, SEM micrographs showed the mesoporous SBA-15 and the microporous ZSM-5 as segregate particles evidencing that direct transformation of the SBA-15 pore walls into microporous ZSM-15 is unlikely. An enhanced activity in the isomerization of m-xylene on the recrystallised samples was observed.

Stannous ion has been used in different sectors of human interest, such as in food industry and in health sciences. Much is known about stannous chloride (SnCl(2)) toxicity, although, there is no general agreement regarding its genotoxicity. Cymbopogon citratus, Maytenus ilicifolia and Baccharis genistelloides extracts have been used in popular medicine. We evaluated the influence of these crude extracts on the survival of the Escherichia coli wild type (AB 1157) strain submitted to SnCl(2) treatment. Reactive oxygen species (ROS) can be generated by a Fenton like reaction induced by SnCl(2). E. coli culture was treated simultaneously with SnCl(2) and a specific extract. Our results showed a reduction of the SnCl(2) effect on the survival of the cultures in presence of the crude extracts. The extract of M. ilicifolia showed the highest level of protection action against the SnCl(2) effect in comparison with the other extracts. This protector effect could due to the redox properties of these crude extracts. The compounds in the crude extracts could (i) chelate stannous ions, protecting them against the oxidation and avoiding the generation of ROS, (ii) be a scavenger of the ROS generated by the SnCl(2) oxidation and/or (iii) have oxidant compounds that could oxidise the stannous ions, abolishing or reducing the SnCl(2) effect.

The influence of drugs on the labeling of red blood cells and plasma proteins with 99mTc has been reported. Any drug, which alters the labeling of the tracer, could be expected to modify the disposition of the radiopharmaceuticals. Red blood cells (RBC) labeled with technetium-99m (99mTc) are used for several evaluations in nuclear medicine. We have evaluated the effect of Thuya occidentalis, Peumus boldus and Nicotiana tabacum (tobacco) extracts on the labeling of RBC and plasma and cellular proteins with 99mTc. Blood was incubated with the drugs. Stannous chloride (SnCl2) solutions and 99mTc were added. Plasma (P) and blood cells (BC) were separated. The percentage of radioactivity (%ATI) bound to P and BC was determined. The %ATI on the plasma and cellular proteins was also evaluated by precipitation of P and BC samples with trichloroacetic acid (TCA) and isolation of soluble (SF) and insoluble (IF) fractions. The analysis of the results shows that there is a decrease in %ATI (from 97.64 to 75.89 percent) in BC with Thuya occidentalis extract. The labeling of RBC and plasma proteins can be decreased in presence of tobacco. This can be due either a direct or indirect effect (reactive oxygen species) of tobacco. The analysis of radioactivity in samples of P and BC isolated from samples of whole blood treated with Peumus boldus showed a rapid uptake of the radioactivity by blood cells in the presence of the Peumus boldus, whereas there was a slight decrease in the amount of 99mTc radioactivity in the TCA-insoluble fraction of plasma. This study shows that extracts of some medicinal plants can affect the radiolabeling of red blood cells with 99mTc using an in vitro technique.

Peumus boldus extract has been used in popular medicine in the treatment of biliar litiase, hepatic insufficiency and liver congestion. Its effects are associated to the substance boldine that is present in its extract. In the present work, we evaluated the influence of boldine both in: (i) the structural conformation of a plasmid pUC 9.1 through gel electrophoresis analysis; and in (ii) the survival of the strain of Escherichia coli AB1157 submitted to reactive oxygen species (ROS), generated by a Fenton like reaction, induced by stannous chloride. Our results show a reduction of the lethal effect induced by stannous chloride on the survival of the E. coli culture in the presence of boldine. The supercoiled form of the plasmid is not modified by stannous chloride in the presence of boldine. We suggest that the protection induced by boldine could be explained by its anti-oxidant mechanism. In this way, the boldine could be reacting with stannous ions, protecting them against the oxidation and, consequently, avoiding the generation of ROS.

The effects of intraseptal injection of carbachol on natriuresis, kaliuresis and diuresis has been studied in conscious, unrestrained water-loaded male rats. Urinary sodium and potassium excretion increased following injections into the septal area. The intensity of the natriuresis and kaliuresis was dose-related. An antidiuretic effect was also observed. The Na + /K + ratio increased with increasing doses of carbachol, indicating that the rise in urinary sodium exceeded that of potassium. Systematic mapping of the septal area yielded about the same results for all sites, excepting a zone located in the anterior-dorsal part of the medial nucleus which appeared more sensitive. The natriuretic effect of intraseptal carbachol in adrenalectomized rats demonstrated the secondary role played by the adrenals. Contrariwise the decrease of the natriuretic effect observed either in hypophysectomized rats or in rats bearing a median eminence lesion receiving intraseptal carbachol showed the important participation of these structures in urinary Na + excretion. Adrenalectomy or median eminence lesions did not modify the kaliuretic response while hypophysectomy produced a transitory diminution. This fact favours the hypothesis of different mechanisms involved in Na + and K + excretion following intraseptal carbachol. These results leave open the question as to mechanism of action but suggest a possible role of the pituitary in mediating the responses. Also, the possibility of a role played by hemodynamic shifts is suggested.

The effect of intraseptal injection of carbachol and nicotine on urinary output of Na+ and K+ in untreated rats as well as in animals pretreated with locally injected atropine, hexamethonium, dibenamine and propranolol was studied in order to evaluate the relative role played by central muscarinic and nicotinic receptors in the regulation of salt and water renal excretion. The injection of 30-250 nmol of nicotine into the medial septal area caused a dose-dependent increase in Na+ and K+ urinary output whereas urine volume was little affected. The effect of 30 nmol of nicotine was blocked by pretreatment with 100 nmol of hexamethonium. In addition, pretreatment with 5 nmol of either hexamethonium or atropine partially antagonized the natriuretic and kaliuretic effect of 1 nmol of carbachol. Also the alpha-blocking agent, dibenamine (150 nmol) antagonized, while the beta-blocker, propranolol (100 nmol) significantly enhanced the effect of carbachol. Propranolol (100 nmol) alone caused a small, but significant increase in Na+ and K+ renal excretion. These results indicate that stimulation of both muscarinic and nicotinic receptors in the septal area, as caused by carbachol, elicits increased disposition of Na+ and K+ by the kidneys. Also, part of the effects of carbachol appear to be mediated by the release of endogenous catecholamines, acting on central alpha receptors to increase Na+ and K+ urinary excretion. On the other hand, simultaneous activation of beta-receptors by the released amines would partially inhibit this effect.

In this study, the participation of the adenylcyclase - cAMP system of the rat septal area in the mediation of the natriuretic, kaliuretic and diuretic effects of noradrenaline (NA) was investigated. The intraseptal injection of 20 nmol of NA caused a significant increase in the urinary excretion of Na+ and K+ as well as in the urinary volume during the 2 hr period following the intracerebral injection which was blocked by 40 nmol of phentolamine, locally injected, 30 min before the catecholamine. In contrast, pretreatment with propranolol (100 nmol) potentiated the effects of NA on salt and water renal excretion. The intraseptal injection of 3.12 to 50 nmol of dibutyryl cyclic adenosine monophosphate (db cAMP) caused dose-dependent increase in natriuresis and kaliuresis, but a decrease in urinary volume. Under the same experimental conditions, caffeine administration (6.25 to 100 nmol) also induced dose-dependent increases in Na+ and K+ urinary output. These results indicate that the saluretic effect of NA may be mediated by an alpha receptor-induced activation of the adenylcyclase - cAMP system in the septal area.

In order to evaluate the relative roles played by the central beta-receptors in the regulation of renal excretion of Na+, K+ and urine volume a study was carried out on the effect of intraseptal injections of isoproterenol on untreated rats and on rats pretreated with locally injected butoxamine and practolol. Injection of 20–160 nmol isoproterenol into the median septal area elicited a dose dependent decrease in Na+, K+ and urinary volume. Intraseptal injection of 40 nmol isoproterenol elicited a significant decrease in Na+ urinary excretion and in urinary volume during the 2 hr period immediately following injection. This effect was blocked by 160 nmol of locally injected butoxamine administered before isoproterenol. In contrast, pretreatment with practolol (160 nmol) did not alter the effect induced by isoproterenol. Pretreatment with these beta1 and beta2 antagonists did not abolish the effect of isoproterenol on K+ urinary excretion. The beta2 agonist agents, terbutaline and salbutamol, elicited a significant decrease in renal excretion of water and of the two salts. These results indicate that activation of beta2 receptors in the septal area elicits a decrease in Na+ and urinary volume excretion, while the same effect on K+ cannot be described as being due to type 2 beta-receptors.