Chlorine dioxide against bacteria and yeasts from the alcoholic fermentation

The ethanol production in Brazil is carried out by fed-batch or continuous process with cell recycle, in such way that bacterial contaminants are also recycled and may be troublesome due to the substrate competition. Addition of sulphuric acid when inoculum cells are washed can control the bacterial growth or alternatively biocides are used. This work aimed to verify the effect of chlorine dioxide, a well-known biocide for bacterial decontamination of water and equipments, against contaminant bacteria ( Bacillus subtilis, Lactobacillus plantarum, Lactobacillus fermentum and Leuconostoc mesenteroides) from alcoholic fermentation, through the method of minimum inhibitory concentration ( MIC), as well as its effect on the industrial yeast inoculum. Lower MIC was found for B. subtilis ( 10 ppm) and Leuconostoc mesenteroides ( 50 ppm) than for Lactobacillus fermentum ( 75 ppm) and Lactobacillus plantarum ( 125 ppm). Additionally, these concentrations of chlorine dioxide had similar effects on bacteria as 3 ppm of Kamoran (R) ( recommended dosage for fermentation tanks), exception for B. subtilis, which could not be controlled at this Kamoran (R) dosage. The growth of industrial yeasts was affected when the concentration of chlorine dioxide was higher than 50 ppm, but the effect was slightly dependent on the type of yeast strain. Smooth yeast colonies ( dispersed cells) seemed to be more sensitive than wrinkled yeast colonies ( clustered cells/pseudohyphal growth), both isolated from an alcohol-producing unit during the 2006/2007 sugar cane harvest. The main advantage in the usage of chlorine dioxide that it can replace antibiotics, avoiding the selection of resistant populations of microorganisms.

Anticoccidial effects of coumestans from Eclipta alba for sustainable control of Eimeria tenella parasitosis in poultry production

The aim of this study was to evaluate the anticoccidial efficacy of a product containing coumestans from Eclipta alba. Experimental conditions were set up as to reproduce the environment conditions for husbandry adopted in commercial broiler farms. Broilers were raised in broiler chicken shed provided with feeders, drinkers, illumination and temperature control systems and floor covering to afford an adequate nourishing environment. Male Cobb broilers (240) were assigned to four experimental groups being each experimental group set apart in rice straw-covered shed isolated with wire mesh. One-day-old broilers were reared in a coccidian-free environment with ad libitum supply of filtered water and freely available standard feed, from the 1st to the 35th day of life. The T1 group received standard feed (negative control); T2 was treated with standard feed supplemented with 66 ppm of salinomycin (positive control); groups T3 and T4 had standard feed supplemented with the ethyl acetate fraction from methanolic extract of E. alba aerial parts, which contains the coumestans WL and DWL (120 and 180 ppm, respectively). The chicken broilers were individually infected with 2 x 104 oocysts of Eimeria tenella when they were 14 days old and were monitored weekly to evaluate zootechnical parameters such as weight gain and food conversion ratio. Counting of coccidial oocyst in chiken feces was assessed from random samples, from the 21st to 28th days of life, which corresponded to 7-14 days after the infection. Five chickens selected at random from each experimental group were subsequently euthanized at 21, 28 or 35 days of life to determine the lesion score in the cecal region and to excise a cecum portion for histopathological evaluation. The group treated with coumestans from E. alba presented an average weight gain and food conversion ratio higher than the negative control group and similar to the mean value of the positive control group. Coumestan-treated groups showed a significant decrease in the oocyst counting since the 21th day of life and displayed a reduced number of macroscopic lesions. Histopathological evaluations of cecum fragments showed that both treatments induced the migration of defense cells at the site of infection. A severe destruction of the cecal lining was found in the intestinal tract of broilers fed with a coumestans dose of 180 ppm. Overall, our results validate the use of a phytotherapy containing E. alba coumestans at a dose of 120 ppm as a therapeutic or prophylactic agent against avian coccidiosis. (C) 2010 Elsevier B.V. All rights reserved.

Ileal and caecal microbial populations in broilers given specific essential oil blends and probiotics in two consecutive grow-outs

Specific essential oil (EO) blends and probiotics used as feed additives have been shown to promote healthy digestive microbials resulting in improved poultry production. Two consecutive experiments were conducted with broilers fed corn-soybean meal diets to determine comparative effects of feed additives on ileal and caecal microbial populations (MP). Ross 708 broilers were placed in 84 pens with previously used litter and treatments maintained in the same pens for both experiments. Eight treatment groups were fed diets containing: Bacitracin methylene disalicylate (BMD) as positive control (PC); no additives as negative control (NC); three probiotics: BC-30; BioPlus 2B (B2B); and Calsporin; and the essential oil blends Crina Poultry Plus (CPP) at 300 or 150 ppm in the first experiment; and CPP at 300 ppm and Crina Poultry AF at 100 ppm in experiment 2. Starter and grower diets contained the ionophore (Coban). Ileal and caecal samples were collected at 43 days of age from male broilers. The DNA of microbial populations was isolated from digesta samples and analysed by denaturing gradient gel electrophoresis to generate percentage similarity coefficients (%SC) from band pattern dendrograms. Differences were observed in ileal and caecal populations depending on treatment, respectively, and especially between experiments. Broilers fed diets with probiotics had very similar MP. The EO CPP at 300 ppm resulted in ilea! MP similar to those observed in chickens fed probiotics. We concluded that antibiotic treatment affected ileal, but no caecal MP. More pronounced changes in ileal and caecal MP were seen in broilers at 43 days of age following probiotic and essential oil treatments.

Performance of Layers Submitted to Different Forced Molting Methods and Different Temperatures

This study was carried out to evaluate the performance and egg quality of laying hens, in their second laying cycle submitted to different forced-molting methods and three environmental temperatures. Six hundred layers were distributed in a completely randomized experimental design with 15 treatments with five replicates of eight birds each, according to 5x3 factorial arrangement (molting methods vs. temperatures). The following forced-molting methods were applied: 90%, 70%, 50% dietary alfalfa inclusion, addition of 2,800 ppm zinc, and feed fasting. Temperatures were: 20 degrees C, 27 degrees C and 35 degrees C. At the end of each period of the second laying cycle, bird performance and egg quality were evaluated. Data were submitted to analysis of variance and means were compared by orthogonal and polynomial contrasts. The highest alfalfa inclusion level (90% alfalfa and 10% basal diet) proved to be efficient as compared to the other methods, independently of temperature.

Optical chemical sensors using polythiophene derivatives as active layer for detection of volatile organic compounds

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Foraminiferal ecological zonation along a Brazilian mangrove transect: Diversity, morphotypes and the influence of subaerial exposure time.

Two foraminiferal associations comprising only arenaceous species define two distinct environments in a 340 m-long mangrove transect at Cardoso Island, Trapande Bay (Cananeia-Iguape estuarine system, SP, Brazil). The "lower muddy flat" (LMF), from the outer mangrove fringe inwards towards land (100 m), is positioned in the lower plain between 0.04 and 0.23 m above the mean sea level (msl), and remains subaerially exposed between 48.5 and 65.6% of the time. This environment is characterized by higher foraminiferal diversity and evenness (McIntosh's D = 0.54 [plus or minus] 0.21 and Pielou's E = 0.68 [plus or minus] 0.25, respectively) and is dominated by Arenoparrella mexicana and Trochammina inflata, and to a lesser extent by Ammotium directum and Textularia earlandi. The mangrove plant of this segment is a Rhizophoretum with average height of 8.4 [plus or minus] 1.2 m. The sediment is characterized by higher concentration of organic matter (93.5 [plus or minus] 32.3 g dm-3) and metals (e.g. V = 53.4 [plus or minus] 21.8 ppm and Zn = 46.4 [plus or minus] 21.3 ppm). The "upper sandy flat" (USF), 240 m wide along the transect, is positioned in the upper plain between 0.28 and 0.89 m above the msl, and remains subaerially exposed between 69.7 and 98.5% of the time. This environment is characterized by a lower diversity and evenness (D = 0.33 [plus or minus] 0.17 and E = 0.49 [plus or minus] 0.20, respectively). The association is dominated by species T. inflata and Miliammina fusca. The Rhizophoretum exhibits a lower average height of 3.6 [plus or minus] 0.6 m. The sediment is poorer in organic matter (39.3 [plus or minus] 15.0 g dm-3) and metals (e.g. V = 13.0 [plus or minus] 6.8 ppm and Zn = 6.9 [plus or minus] 3.7 ppm). Whereas "elongate" tests (uniserial, biserial and planospiral followed by a uniserial portion) are restricted to the LMF, "spiraled" species dominate the USF. Subaerial exposure time seems to exert a primary influence on species distribution, in addition to salinity and sediment type. Species may be adapted to different exposure times, a factor dependent on their position on the intertidal zone and the tidal regime, which should be taken into account in relative sea level reconstructions based on intertidal foraminifera. These patterns have important implications for studies investigating the ecology and paleoecology of foraminifera and subtle fluctuations in relative sea level during the Quaternary.

Europium(III) Concentration Effect on the Spectroscopic and Photoluminescent Properties of BaMoO4:Eu

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Use of Natural Products for Post-Harvest Preservation of 'Vega' Cut Roses

Use of natural products as floral preservatives has helped to reduce the indiscriminate use of chemical products in flower preservation. In this study, we tested the ability of certain natural products to maintain the quality and to increase the commercial durability of 'Vega' cut roses. We employed a randomized factorial design with six post-harvest treatments and four evaluation dates. The following treatments were tested: 1) distilled water; 2) methyl jasmonate (350 mu M) applied in a four-hour pulse; 3) methyl jasmonate (500 mu M) spraying; 4) mint oil (100 ppm); 5) ginger oil (100 ppm); and 6) propolis (0.05%) as a maintenance solution. Flowers were kept at 20+/-2 degrees C and 67+/-3% RH. Physiological and qualitative evaluations were conducted. Natural products had a beneficial effect on the shelf life of the flowers. However, for all evaluated parameters, the methyl jasmonate spray was the most efficient treatment to maintain floral quality, resulting in less fresh-mass loss and a lower flower respiratory rate. Methyl jasmonate spray also improved the maintenance of coloration, relative water content and concentration of reducing sugars, thus extending the shelf life of roses.

Photoluminescence property of Ba(Zr0.25Ti0.75)O-3 powders prepared by solid state reaction and polymeric precursor method

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effect of saliva substitutes in combination with fluorides on remineralization of subsurface dentin lesions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Reply to Comment on 'Pb1-xCaxTiO3 solid solution (x=0.0, 0.25, 0.50, and 0.75): A theoretical and experimental approach'

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Linamarin - The toxic compound of cassava

Cassava is a widely grown root crop which accumulates two cyanogenic glucosides, linamarin and lotaustralin. Linamarin accounts for more than 80% of the cassava cyanogenic glucosides. It is a β-glucoside of acetone cyanohydrin and ethyl-methyl-ketone-cyanohydrin. Linamarin β-linkage can only be broken under high pressure, high temperature and use of mineral acids, while its enzymatic break occurs easily. Linamarase, an endogenous cassava enzyme, can break this β-linkage. The enzymatic reaction occurs under optimum conditions at 25°C, at pH 5.5 to 6.0. Linamarin is present in all parts of the cassava plant, being more concentrated on the root and leaves. If the enzyme and substrate are joined, a good detoxification can occur. All the cassava plant species are known to contain cyanide. Toxicity caused by free cyanide (CN-) has already been reported, while toxicity caused by glucoside has not. The lethal dose of CN- is 1 mg/kg of live weight; hence, cassava root classification into toxic and non-toxic depending on the amount of cyanide in the root. Should the cyanide content be high enough to exceed such a dose, the root is regarded as toxic. Values from 15 to 400 ppm (mg CN-/kg of fresh weight) of hydrocyanic acid in cassava roots have been mentioned in the literature. However, more frequent values in the interval 30 to 150 ppm have been observed. Processed cassava food consumed in Brazil is safe in regard to cyanide toxicity.

Acute, subchronic and chronic 2,4-dichlorophenoxyacetic acid (2,4-D) intoxication in rats

The acute, subchronic and chronic toxicities of 2,4- dichlorophenoxyacetic acid (2,4-D) were studied in rats. Animals were exposed acutely (600 mg/kg), subchronically (200 ppm for 30 d) and chronically (200 ppm for 180 d) to 2,4-D by the oral route. Clinical, laboratory and histopathological methods were used as indicators of toxicity. After acute exposure, the herbicide decreased locomotor activity and induced ataxia, sedation, muscular weakness (mainly of the hind quarters) and gasping for breath; increased aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (AP), amylase activities and creatinine levels; decreased total protein (TP) and glucose levels; and increased hematocrit values. Subchronic and chronic 2,4-D exposures did not induce overt clinical signs or symptoms of intoxication. However, subchronic herbicide exposure increased AST activity and albumin and hematocrit values, and chronic exposure increased AST, AP and LDH activities, decreased amylase and glucose levels, but did not change hematocrit values. Chromatographic analysis of the serum of chronically exposed rats showed the presence of the herbicide; the amount found (3.76 ± 1.16 mg/ml) suggested the absence of 2,4-D accumulation within the body. Although macroscopic or histopathological lesions were not observed in acutely, subchronically or chronically 2,4-D exposed rats, the laboratory data obtained suggest tissue injuries after dosing, since the results are considered early indicators of primarily hepatic and muscle tissue damage.

Determination and persistence of methiocarb in artichokes

A simple and rapid method for the determination of methiocarb in artichokes by high-performance liquid chromatography with UV detection is described. No derivatization is needed and the limit of determination (0.01 ppm) is analogous to that of fluorometric detection. The results of trials carried out with granular and liquid formulations of this active ingredient are also reported. Immediately after treatment with the liquid formulation methiocarb residues averaged 1.47 ppm, while after treatment with the granular formulation residues were considered fortuitous. The decay rate of methiocarb residues in artichokes shows that the decrease and eventual disappearance of this active ingredient can chiefly be ascribed to the dilution effect due to head growth.

Substituição do farelo de soja pelo de guandu na alimentação de frangos de corte

The objective of this work was to evaluate the nutritive value of pigeon pea meal (PPM) with methionine substituting soybean meal (SM) in diets for 1-28 day-old broiler chicks. The experimental design was that of random blocks, in a 3 × 3 factorial scheme with three substitution levels - 15,30 and 45% - and three methionine supplementation levels in relation to the requirements, that is: 100, 66 and 33%, with four repetitions. It was found that PPM treated for 20 minutes at 100°C substituted up to 30% of the SM, even without methionine supplementation, in relation to liveweight (p<0.01), to food conversion and to the efficiency of utilization of metabolizable energy and to protein (p<0.05). At the 66% level of methionine supplementation, the same results as for these parameters were obtained at all of the levels of substitution of SM by PPM. The 30% or 45% substitution of SM protein by that of PPM affected (p<0.01) the efficiency of methionine utilization. The sulphur amino acid utilization efficiency was affected (p<0.01) beginning at 66% methionine supplementation in the diets.