Foundation and Perspectives of the Use of Plant Extracts as Performance Enhancers in Broilers

Feed is responsible for about 70% of broilers production costs, leading to an increasing number of studies on alternative dietary products that benefit bird performance and lower production costs. Since the 1950s, antimicrobial additives are the most frequently used performance enhancers in animal production and their positive results are observed even in high-challenge conditions. Since the 1990s, due to the ban of the use of some antibiotics as growth promoters and the growing trend of the public to consume natural products, plant extracts have been researched as alternatives to antibiotic growth promoters. The first study that evaluated the antibacterial activities of plant extracts was carried out in 1881; however, they started to be used as flavor enhancers only during the next decades. With the emergence of antibiotics in the 1950s, the use of plant extracts as antimicrobial agents almost disappeared. There are several studies in literature assessing the use of plant extracts, individually or in combination, as antimicrobials, antioxidants, or digestibility enhancers in animal feeds. Research results on the factors affecting their action, such as plant variety, harvest time, processing, extraction, as well as the technology employed to manufacture the commercial product and dietary inclusion levels show controversial results, warranting the need of further research and standardization for the effective use of plant extracts as performance enhancers, when added to animal feeds. This article aims at presenting plant extracts as alternatives to antibiotics, explaining their main modes of action as performance enhancers in broiler production.

Sensory evaluation of precooked chicken meat with mate (Ilex paraguariensis) added as antioxidant

Dried mate leaves or aqueous extract of dried mate leaves added to chicken meat balls prior to cooking for antioxidant protection was found not to affect taste or smell of the product significantly for addition corresponding to 0.050% of dried mate leaves, while 0.10% changed the smell but not the taste and more significantly for dried leaves. Addition of aqueous mate extract corresponding to 0.050% of mate is recommended as an alternative to more strongly flavoured herbs for oxidative protection of meat products.

A conserved dibasic site is essential for correct processing of the peptide hormone AtRALF1 in Arabidopsis thaliana

Prohormone proteins in animals and yeast are typically processed at dibasic sites by convertases. Propeptide hormones are also found in plants but little is known about processing. We show for the first time that a dibasic site upstream of a plant peptide hormone, AtRALF1, is essential for processing. Overexpression of preproAtRALF1 causes semidwarfism whereas overexpression of preproAtRALF1(R69A), the propeptide with a mutation in the dibasic site, shows a normal phenotype. RALF1(R69A) plants accumulate only the mutated proprotein and not the processed peptide. In vitro processing using microsomal fractions suggests that processing is carried out by a kexin-like convertase. (C) 2008 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.

Mate (Ilex paraguariensis) as a source of water extractable antioxidant for use in chicken meat

Aqueous extract of mate, made from dried leaves of Ilex paraguariensis, St. Hilaire, was shown to be effective during chilled storage for up to 10 days in protecting lipids and vitamin E against oxidation in pre-cooked meat balls made from chicken breast added 0.5% salt and packed in atmospheric air. Extracts made with water, methanol, ethanol or 70% aqueous acetone were evaluated by comparing (1) total phenolic content, (2) radical scavenging capacity, (3) effect on lipid oxidation in a food emulsion model, and in liposomes. Based on the three-step evaluation, aqueous mate extract was preferred for food use. Dried leaves were further compared to dried rosemary leaves in chicken meat balls, and mate (0.05 and 0.10%) found to yield equal or better protection than rosemary at the same concentration against formation of secondary lipid oxidation products.

High prevalence, low counts and uncommon serotypes of Listeria monocytogenes in linguica, a Brazilian fresh pork sausage

Linguica is a highly popular and appreciated pork product in Brazil, frequently consumed undercooked. Aiming at collection of data for a future risk assessment, this study evaluated the prevalence and counts of Listeria monocytogenes in linguica samples collected at retail level in Sao Paulo, SP, Brazil. ISO methods were used for detection and enumeration of the pathogen (11290-1 and 11290-2, respectively). Isolates were submitted to Simplex-PCR for hlyA gene and those with biochemical features of L. monocytogenes and hlyA positive were serotyped using a Multiplex PCR. Ninety percent of the samples were positive for Listeria spp., and L monocytogenes was detected in 42% of the samples, with counts below 10(2) CFU/g in all samples. A prevalence of uncommon serotypes 4a and 4c was observed. (C) 2009 Elsevier Ltd. All rights reserved.

Determination of volatiles produced during radiation processing in Laurus cinnamomum

In order to protect food from pathogenic microorganisms as well as increase its shelf-life, while keeping sensorial properties (e.g., odor and taste), which are important properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. Possible changes in the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties, in order to allow better application of the irradiation technology. The aim of the present study was to analyze volatile formation on cinnamon (Laurus cinnamomum) samples after gamma irradiation. These samples were irradiated into plastic packages using a (60)Co facility. Radiation doses applied were 0, 5, 10, 15, 20 and 25 kGy. For the analysis of the samples, solid-phase microextraction (SPME) was applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation showed the highest decrease in volatile compounds. For L. cinnamomum, the irradiation decreased volatile compounds by nearly 56% and 89.5%, respectively, comparing to volatile from a sample which had not been previously irradiated. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.

Listeria monocytogenes in two different poultry facilities: Manual and automatic evisceration

Listeriosis is a serious foodborne disease caused by Listeria monocytogenes, a pathogen often found in food processing plants. Poultry meat and its derivatives may harbor L. monocytogenes even if good manufacturing practices are implanted in abattoirs. Little information exists in Brazil on the frequency of L. monocytogenes contamination, even though the country is considered the top poultry meat exporter in the world. This study attempted to compare 2 exporters poultry facilities following same the standards but differing only in manual (plant M) or automatic (plant A) evisceration. Eight hundred fifty-one samples from food, food contact and non-food contact surfaces, water, and workers` hands were collected from cage to finished products over a 1-yr period. In plant A, 20.1% of the samples were positive for L. monocytogenes, whereas in plant M, 16.4% was found. The greatest incidence of contamination with the pathogen in plant A was found in non- food contact surfaces (27.3%), while in plant M, it was found in products (19.4%). The most prevalent serovars were 1/2a or 3a (plant M) and 4b, 4d, or 4e (plant A). Despite having proper hygiene and good manufacturing practices, controlling the entry and persistence of L. monocytogenes in processing facilities remains a formidable task.

Processing optimization of probiotic yogurt containing glucose oxidase using response surface methodology

Exposure to oxygen may induce a lack of functionality of probiotic dairy foods because the anaerobic metabolism of probiotic bacteria compromises during storage the maintenance of their viability to provide benefits to consumer health. Glucose oxidase can constitute a potential alternative to increase the survival of probiotic bacteria in yogurt because it consumes the oxygen permeating to the inside of the pot during storage, thus making it possible to avoid the use of chemical additives. This research aimed to optimize the processing of probiotic yogurt supplemented with glucose oxidase using response surface methodology and to determine the levels of glucose and glucose oxidase that minimize the concentration of dissolved oxygen and maximize the Bifidobacterium longum count by the desirability function. Response surface methodology mathematical models adequately described the process, with adjusted determination coefficients of 83% for the oxygen and 94% for the B. longum. Linear and quadratic effects of the glucose oxidase were reported for the oxygen model, whereas for the B. longum count model an influence of the glucose oxidase at the linear level was observed followed by the quadratic influence of glucose and quadratic effect of glucose oxidase. The desirability function indicated that 62.32 ppm of glucose oxidase and 4.35 ppm of glucose was the best combination of these components for optimization of probiotic yogurt processing. An additional validation experiment was performed and results showed acceptable error between the predicted and experimental results.

Antimicrobial compounds produced by Lactobacillus sakei subsp sakei 2a, a bacteriocinogenic strain isolated from a Brazilian meat product

Bacteriocins produced by lactic acid bacteria are gaining increased importance due to their activity against undesirable microorganisms in foods. In this study, a concentrated acid extract of a culture of Lactobacillus sakei subsp. sakei 2a, a bacteriocinogenic strain isolated from a Brazilian pork product, was purified by cation exchange and reversed-phase chromatographic methods. The amino acid sequences of the active antimicrobial compounds determined by Edman degradation were compared to known protein sequences using the BLAST-P software. Three different antimicrobial compounds were obtained, P1, P2 and P3, and mass spectrometry indicated molecular masses of 4.4, 6.8 and 9.5 kDa, respectively. P1 corresponds to classical sakacin P, P2 is identical to the 30S ribosomal protein S21 of L. sakei subsp. sakei 23 K, and P3 is identical to a histone-like DNA-binding protein HV produced by L. sakei subsp. sakei 23 K. Total genomic DNA was extracted and used as target DNA for PCR amplification of the genes sak, lis and his involved in the synthesis of P1, P2 and P3. The fragments were cloned in pET28b expression vector and the resulting plasmids transformed in E. coli KRX competent cells. The transformants were active against Listeria monocytogenes, indicating that the activity of the classical sakacin P produced by L. sakei 2a can be complemented by other antimicrobial proteins.

Auditory processing disorder in perisylvian syndrome

We hypothesized that the processing of auditory information by the perisylvian polymicrogyric cortex may be different from the normal cortex. To characterize the auditory processing in bilateral perisylvian syndrome, we examined ten patients with perisylvian polymicrogyria (Group 1) and seven control children (Group 11). Group I was composed by four children with bilateral perisylvian polymicrogyria and six children with bilateral posterior perisylvian polymicrogyria. The evaluation included neurological and neuroimaging investigation, intellectual quotient and audiological assessment (audiometry and behavior auditory tests). The results revealed a statistically significant difference between the groups in the behavioral auditory tests, Such as, digits dichotic test, nonverbal dichotic test (specifically in right attention), and random gap detection/random gap detection expanded tests. Our data showed abnormalities in the auditory processing of children with perisylvian polymicrogyria, suggesting that perisylvian polymicrogyric cortex is functionally abnormal. We also found a correlation between the severity of our auditory findings and the extent of the cortical abnormality. (C) 2009 Elsevier B.V. All rights reserved.

OCCURRENCE AND ANTIBIOTIC SENSIBILITY PROFILE OF Salmonella spp. ISOLATED FROM PORK MEAT CUTS COMMERCIALIZED IN THE OPEN MARKETS IN PELOTAS, RS (BRAZIL)

The objective of the present study was to evaluate the occurrence of Salmonella spp. in 15 samples of pork meat cuts (T-bone, shank, sausage and ribs) commercialized in open markets of Pelotas (RS, Brazil) and verify the prevalent serovars, and test the isolates profile of sensitivity to several antibiotics of importance in medicine (nalidixic acid, ampicillin, aztreonam, kanamycin, carbenicillin, cephalothin, cefoxitin, ceftriaxone, ciprofloxacin, chloramphenicol, gentamicin, sulfonamide, tetracycline and trimetoprina). Twelve samples (80%) were contaminated by Salmonella enterica, serovars Infantis, Derby, Panama and Typhimurium. All isolates were susceptible to trimetoprin, aztreonam, ciprofloxacin, ceftriaxone and cefoxitin. For the other antibiotics, the pattern of sensitivity varied as serovar. In addition, 39.1% of isolates showed up to be multiresistant.

Electrospray MS-based characterization of beta-carbolines - mutagenic constituents of thermally processed meat

The beta-carbolines 1-methyl-9H-pyrido [3,4-b]indole and 9H-pyrido[3,4b]indole have been implicated as having causative roles in a number of human diseases, such as Parkinson`s disease and cancer. As they can be formed during the heating of protein-rich food, a number of analytical methodologies have been proposed for their detection and quantification in foodstuff For this purpose, LC-MS and LC-MS/MS have emerged as the most specific analytical methods, and the quantification is based on the occurrence of unusual ions, such as [M+H-(H(center dot))](+) and [M + H-2H](+). In this study, we have investigated the formation of these ions by accurate-mass electrospray MS/MS and demonstrated that these ions are formed from gas-phase ion-molecule reactions between water vapor present in the collision cell and the protonated molecule of 1-methyl-9H-pyrido [3,4-b]indole and 9H-pyrido[3,4b]indole. Although this reaction has been previously described for heterocyclic amine ions, it has been overlooked in the most of recent LC-MS and LC-MS/MS studies, and no complete data of the fragmentation are reported. Our results demonstrate that additional attention should be given with respect to eliminating water vapor residues in the mass spectrometer when analysis of beta-carbolines is performed, as this residue may affect the reliability in the results of quantification.

Processing of Rosmarinus officinalis Linne extract on spray and spouted bed dryers

This article presents an investigation of the potential of spray and spouted bed technology for the production of dried extracts of Rosmarinus officinalis Linne, popularly known as rosemary. The extractive solution was characterized by loss on drying, extractable matter and total phenolic and flavonoid compounds (chemical markers). The product was characterized by determination of loss on drying, size distribution, morphology, flow properties and thermal degradation and thermal behavior. The spray and spouted bed dryer performance were assessed through estimation of thermal efficiency, product accumulation and product recovery. The parameters studied were the inlet temperature of the spouting gas (80 and 150 degrees C) and the feed mass flow rate of concentrated extract relative to the evaporation capacity of the dryer, W-s/W-max (15 to 75%). The atomizing air flow rate was maintained at 20 l/min with a pressure of 196.1 kPa. The spouting gas flow rate used in the drying runs was 40% higher than the gas flow under the condition of minimum spouting. The spray drying gas flow rate was fixed at 0.0118 kg/s. Under the conditions studied, performance in the spray and spouted bed drying of rosemary extract was poor, causing high degradation of the marker compounds (mainly the phenolic compounds). Thus, process improvements are required before use on an industrial scale.

Trypanosoma cruzi: evaluation of (-)-cubebin derivatives activity in the messenger RNAs processing

No fully effective treatment has been developed since the discovery of Chagas` disease. Since drug-resistant Trypanosoma cruzi strains are occurring and the current therapy is effective in the acute phase but with various adverse side effects, more studies are needed to characterize the susceptibility of T. cruzi to new drugs. Pre-mRNA maturation in trypanosomatids occurs through a process called trans-splicing, which is unusual RNA processing reaction, and it implies the processing of polycistronic transcription units into individual mRNAs; a short transcript spliced leader (SL RNA) is trans-spliced to the acceptor pre-mRNA, giving origin to the mature mRNA. Cubebin derivatives seem to provide treatments with less collateral effects than benznidazole and showed similar or better trypanocidal activities than benznidazole. Therefore, the cubebin derivatives ((-)-6,6`-dinitrohinokinin (DNH) and (-)-hinokinin (HQ)) interference in the mRNA processing was evaluated using T. cruzi permeable cells (Y and BOL (Bolivia) strains) following by RNase protection reaction. These substances seem to intervene in any step of the RNA transcription, promoting alterations in the RNA synthesis, even though the RNA processing mechanism still occurs. Furthermore, HQ presented better activity against the parasites than DNH, meaning that BOL strain seems to be more resistant than Y.

Fermentative production of hydrogen from cassava processing wastewater by Clostridium acetobutylicum

This work reports on the effect of initial substrate concentration on COD consumption, pH, and H(2) production during cassava processing wastewater fermentation by Clostridium acetobutylicum ATCC 824. Five initial COD wastewater concentrations, namely 5.0, 7.5, 10.7, 15.0, and 30.0 g/L, were used. The results showed that higher substrate concentrations (30.0 and 15.0 COD/L) led to lower H(2) yield as well as less efficient substrate conversion into H(2). On the other hand, initial COD concentrations of 10.7, 7.5 and 5 g/L furnished 1.34, 1.2 and 2.41 mol H(2)/mol glucose, with efficiency of glucose conversion into H(2) of 34, 30, and 60% (mol/mol), respectively. These results demonstrate that cassava processing wastewater, a highly polluting effluent, can be successfully employed as substrate for H(2) production by C acetobutylicum at lower COD concentrations. (C) 2011 Elsevier Ltd. All rights reserved.