Kinetic enzymatic determination of glycerol in wine and beer using a sequential injection system with spectrophotometric detection

A sequential injection system for the automatic determination of glycerol in wine and beer was developed. The method is based on the rate of formation of NADH from the reaction of glycerol and NAD+ catalyzed by the enzyme glycerol dehydrogenase in solution. The determination of glycerol was performed between 0.3 and 3.0 mmol L(-1) (0.028 and 0.276 g L(-1)), and good repeatability was attained (rsd < 3.6%, n = 5) for all samples tested. The determination rate was 54 h(-1), the reagent consumption was only 0.75 micromol of NAD+ and 5.4 ng of enzyme per assay, and the waste production was 2.12 mL per assay. Results obtained for samples were in agreement with those obtained with the batch enzymatic method.     

Contents of carboxylic acids and two phenolics and antioxidant activity of dried portuguese wild edible mushrooms

The organic acids and phenolics compositions of nine wild edible mushrooms species (Suillus bellini, Tricholomopsis rutilans, Hygrophorus agathosmus, Amanita rubescens, Russula cyanoxantha, Boletus edulis, Tricholoma equestre, Suillus luteus, and Suillus granulatus) were determined by HPLC-UV and HPLC-DAD, respectively. The antioxidant potential of these species was also assessed by using the DPPH* scavenging assay. The results showed that all of the species presented a profile composed of at least five organic acids: oxalic, citric, malic, quinic, and fumaric acids. In a general way, the pair of malic plus quinic acids were the major compounds. Only very small amounts of two phenolic compounds were found in some of the analyzed species: p-hydroxybenzoic acid (in A. rubescens, R. cyanoxantha, and T. equestre) and quercetin (in S. luteus and S. granulatus). All of the species exhibited a concentration-dependent scavenging ability against DPPH*. T. rutilans revealed the highest antioxidant capacity.     

Modeling the Potential Geographic Distribution of Black Pepper（Piper nigrum）in Asia Using GIS Tools

Known as the "king of spices",black pepper (Piper nigrum),a perennial crop of the tropics,is economically the most important and the most widely used spice crop in the world.To understand its suitable ...     

Characterization of extraintestinal Escherichia coli isolated from a peacock (Pavo cristatus) with colisepticemia

Extraintestinal infections by avian pathogenic strains of Escherichia coli (APEC) are commonly reported in poultry, but there is little information on infections by APEC in other bird species. Here we report on the characterization of extraintestinal E. coli isolated from a domesticated peacock, from the south of Brazil, that died of colisepticemia. Necropsy examination revealed congested liver, hypertrophied kidneys, peritonitis, severe typhlitis suggestive of coligranuloma, pneumonia, and airsacculitis--typical signs of colisepticemia. The isolates from lungs, kidney, heart, intestine, liver, and bone marrow all harbored the same virulence-associated factors (iucD, colV, iss, mat, fimC, ompA, traT crl, csgA vgrG, and hcp), yielded the same band pattern in amplified ribosomal DNA restriction analysis, and were allocated to the Escherichia coli Reference Collection group B1. The isolates were resistant to bacitracin, trimethoprim, and tetracycline, but displayed slight differences in their resistance to other antimicrobials. The isolates also differed in their virulence in 1-day-old chickens, but none displayed high virulence in vivo. We conclude that the peacock died of colisepticemia after it was infected with an extraintestinal E. coli strain of low virulence that nevertheless harbored virulence factors generally associated with APEC. This study represents the first characterization of an APEC isolated from a nonpoultry bird species.     

The thermostable β-1,3-1,4-glucanase from Clostridium thermocellum improves the nutritive value of highly viscous barley-based diets for broilers

1. Microbial β-1,3-1,4-glucanases improve the nutritive value of barley-based diets for poultry by effectively decreasing the degree of polymerisation of the anti-nutritive soluble β-glucans. Glycoside hydrolases (GHs) acting on recalcitrant polysaccharides display a modular architecture comprising a catalytic domain linked to one or more non-catalytic Carbohydrate-Binding Modules (CBMs).

2. GHs and CBMs have been classified in different families based on primary structure similarity (see CAZy webpage at http://www.cazy.org). The role of CBMs is to anchor the appended GHs into their target substrates, therefore eliciting the efficient hydrolysis of structural carbohydrates.

3. Here we describe the biochemical properties of the family 16 GH from Clostridium thermocellum, termed CtGlc16A. CtGlc16A is a thermostable enzyme that specifically acts on β-1,3-1,4-glucans with a remarkable catalytic activity (38000?U/mg protein).

4. CtGlc16A, individually or fused to the family 11 β-glucan-binding domain of cellulase CtLic26A-Cel5E of C. thermocellum, was used to supplement a highly viscous barley-based diet for broilers.

5. The data showed that birds fed on diets supplemented with the recombinant enzymes displayed an improved performance when compared with birds given diets not supplemented with exogenous enzymes. However, inclusion of the non-catalytic CBMs had no influence on the capacity of CtGlc16A to reduce the anti-nutritive effects of soluble β-1,3-1,4-glucans.

6. The data suggest that at elevated dosage rates, CBMs might be unable to potentiate the catalytic activity of appended catalytic domains; this effect may only be revealed when feed enzymes are incorporated at low levels.     

Effect of organic acids and mannanoligosaccharide on excretion of Salmonella typhimurium in experimentally infected growing pigs

The effect of organic acids and mannanoligosaccharide addition to the diet was assessed in pigs orally inoculated with Salmonella typhimurium. Forty-six growers were distributed among four treatments: Basal Diet (BD); BD+encapsulated organic acids; BD+free organic acids; BD+mannanoligosaccharide. Seroconversion was monitored, and feces and tissue samples were tested for Salmonella isolation. No treatment prevented the carrier state, but a tendency of lower fecal excretion was observed in the group treated with mannanoligosaccharide.     

Influence of different supplements and sugarcane (Saccharum officinarum L.) cultivars on intake, digestible variables and methane production of dairy heifers under tropical conditions

The sulphur hexafluoride (SF(6)) gas tracer method was used to measure methane (CH(4)) production of crossbred (3/4 Holstein x Zebu) dairy heifers fed two types of sugarcane (Saccharum officinarum L.; cultivar IAC-862480 (CC1) or cultivar IAC-873184 (CC2)) and supplemented with urea or concentrate. The study was performed at Embrapa Southeast Cattle, S?o Carlos, SP, Brazil, using a completely randomised design. Differences between treatments were significant for digestibility of dry matter, organic matter and energy. When animals were supplemented with urea differences between sugarcane cultivars did occur for NDF consumption, but not for daily methane production. This suggest that variation in chemical composition of sugarcane did not affect bovine ruminal CH(4) emissions. Concentrate inclusion in animal diet increased digestible organic matter intake, improving the nutrient intake by animals, but did not reduce CH(4) production expressed as a percentage of gross energy intake.     

Resonance of scantlings indicates the stiffness even of small specimens of Eucalyptus from plantations

The aim of this study was to establish the relationship between the stiffness of scantlings, approaching structural size materials, and small specimens of 6-year-old Eucalyptus urophylla?×?grandis wood using a resonance technique. The correlation between the elastic modulus (E) of the scantlings in longitudinal vibration and small specimens in flexural vibration was r?=?75 when comparing the scantling values with the averaged values of the specimens per scantling. However, when the E of each single specimen was compared with its respective scantling, the coefficient of correlation decreased to r?=?0.64 in the longitudinal tests and r?=?0.61 in the flexural tests. A roughly linear correlation (r?=?0.59) between specific modulus and loss tangent was obtained for the small specimens of Eucalyptus. In short, the resonance technique rapidly provided a large, accurate data set of mechanical wood properties as required for high-throughput phenotyping in recent genetic studies.     

Use of a Real Time PCR for detecting subspecies of Babesia canis

This paper reports the development and use of a Real Time PCR for detection of Babesia canis canis, B. canis rossi, and B. canis vogeli in endemic areas of Brazil. The sequences of the internal transcribed spacer (ITS) of several organisms were aligned and five primers and four probes were designed for amplification of a fragment (around 125 bp) which differentiates subspecies of B. canis. Blood samples collected from dogs living in farms in three distinct rural regions within the State of Minas Gerais (Lavras, Belo Horizonte and Nanuque) were tested. Blood samples had been collected during a dry season (Lavras, n=100; Belo Horizonte, n=50; Nanuque, n=102); the dogs were re-sampled in the subsequent rainy season (Lavras, n=71; Belo Horizonte, n=29; Nanuque, n=66). From each sample, DNA was extracted and Giemsa stained smears were microscopically examined for direct detection of Babesia parasites. B. canis vogeli was the only subspecies found, with an overall prevalence of 9.9% during the dry season and 10.8% during the rainy season. Dogs living in Nanuque and Belo Horizonte showed significantly higher prevalence rates than those living in Lavras (13.7%, 12.0% and 5.0%, respectively). The Real Time PCR developed proved to be appropriate to detect B. canis subspecies in endemic areas.