Inhibitory effect of sodium metabisulphite and chlorine on growth of Aspergillus spp. and Penicillium spp. strains isolated from marine shrimp

The sodium metabisulphite (SMB) is used in shrimp farming to prevent melanosis and the 5.0 ppm chlorine (CL) concentration used in the shrimp processing is effi cient as a bactericide, but there is no evidence of the effectiveness of these chemical compounds as fungicides. Therefore, the aim of this study was to evaluate the in vitro effect of sodium metabisulphite (SMB) and chlorine (CL) on the growth of Aspergillus and Penicillium species isolated from marine shrimp in different stages of processing. The samples were collected from a frozen shrimp processing industry, located in Piauí State, Brazil. The total fungi and occurrence of Aspergillus and Penicillium species were evaluated. For in vitro sensibility test using the diffusion disk in agar method, fi ve concentrations of SMB (0%, 1%, 3%, 5% and 10%) and six of CL (0, 1, 2, 3, 4 and 5 μg mL-1) were used. The fungal counts in the different processing stages ranged from 1.74 to 3.38 CFU g-1. Twenty-nine Aspergillus strains were isolated, prevailing A. versicolor (59.3%) and twenty-two of Penicillium, prevailing P. citrinum (74%). One strain of A. fl avus was AFB1 producer. All the isolated strains of P. citrinum produced citrinin. All tested species were in vitro sensitive to 3% of SMB, except the A. fl avus. The 10% concentration of SMB inhibited the in vitro growth of all strains. The CL concentrations tested did not inhibit the studied species growth and SMB concentrations above 3.0% inhibited in vitro the growth of the tested strains. Key words: Aspergillus fl avus, Litopenaeus vannamei, Penicillium citrinum, shrimp culture, conservation. RESUMO O metabissulfi to de sódio (SMB) é usado na carcinicultura para evitar a melanose e a concentração de 5,0ppm de cloro (CL), utilizada no benefi ciamento do camarão, é efi ciente como bactericida, porém não há comprovação da efi cácia destes compostos químicos como fungicida. Desse modo, o objetivo deste estudo foi avaliar o efeito in vitro do metabissulfi to de sódio (SMB) e cloro (CL) sobre o crescimento de espécies de Aspergillus e Penicillium isolados de camarão marinho em diferentes estágios de processamento. As amostras foram coletadas de uma indústria de processamento de camarão congelado, localizada no Estado do Piauí, Brasil. Fungos totais e ocorrência das espécies de Aspergillus e Penicillium foram avaliados. Para o teste in vitro de sensibilidade pelo método disco-difusão em ágar, foram utilizadas cinco concentrações de SMB (0%, 1%, 3%, 5% e 10%) e seis de CL (0, 1, 2, 3, 4 e 5μg mL-1). As contagens fúngicas nos diferentes estágios de processamento variaram de 1,74 a 3,38UFC g-1. Foram isoladas 29 cepas de Aspergillus, prevalecendo o A. versicolor (59,3%) e 22 de Penicillium, prevalecendo o P. citrinum (74%). Uma cepa de A. fl avus era produtora de AFB1. Todas as cepas de P. citrinum isoladas produziram citrinina. Todas as espécies testadas foram sensíveis in vitro a 3% do SMB, com exceção do A. fl avus. A concentração de 10% do SMB inibiu in vitro o crescimento de todas as cepas. As concentrações de CL testadas não inibiram o crescimento das espécies isoladas e concentrações de SMB acima de 3,0% inibiram in vitro o crescimento das linhagens testadas. Palavras-chave: Aspergillus fl avus, Litopenaeus vannamei,Fil: Santos, Ygor Flavio de Moraes. Universidade Federal do Piauí. Centro de Ciências Agrárias; Brasil;Fil: Veloso, Átila Peeter Batista. Universidade Federal do Piauí. Centro de Ciências Agrárias; Brasil;Fil: Calvet, Rodrigo Maciel. Universidade Federal do Piauí. Centro de Ciências Agrárias; Brasil;Fil: Pereira, Maria Marlucia Gomes. Universidade Federal do Piauí. Centro de Ciências Agrárias; Brasil;Fil: Pereyra, Carina Maricel. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales; ArgentinaFil: Dalcero, Ana Maria. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Departamento de Microbiologia E Inmunologia; ArgentinaFil: Torres, Adriana Mabel. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Departamento de Microbiologia E Inmunologia. Cat.de Micología; ArgentinaFil: Muratori, Maria Christina Sanches. Universidade Federal do Piauí. Centro de Ciências Agrárias; Brasil

In vitro adsorption of ochratoxin A by probiotics used in aquaculture

Devido as constantes contaminações de rações comerciais pelas micotoxinas, o presente trabalho teve por objetivo avaliar in vitro a capacidade de dois produtos comerciais utilizados na aquicultura em adsorverem Ochratoxina A (OTA). Dois tipos de probióticos comerciais, compostos por Bacillus subtilis, Bifidobacterium bifidum, Enterococcus faecium e Lactobacillus acidophilus (Probiótico A) e, Saccharomyces cerevisiae provenientes de cervejaria (Probiótico B) foram utilizados no ensaio. Soluções em tampão fosfato salino (PBS), com pH de 1,5 e 7,5, foram elaborados para simular o pH do estômago e intestino de tilápias do Nilo (Oreochromis niloticus). As soluções de PBS foram testadas nas duas faixas de pH (1,5 e 7,5), com as concentrações dos produtos comerciais de 0%; 25%; 50%; 75% e 100%, para uma concentração de 1.000 ng.mL1 de OTA. As concentrações de OTA foram adicionadas em microtubos para que fosse determinado a capacidade de adsorção dos probióticos utilizados neste estudo. Na detecção e quantificação de OTA, utilizou-se a metodologia de Cromatografia Líquida de Alta Eficiência (CLAE). Os resultados finais mostraram que os probióticos A e B nas suas concentrações máximas foram capazes de adsorver OTA nas quantidades de 13,78 a 76,81 e 301,48 a 317,54 (ng.mL-1 ), respectivamente. Os dados mostraram que os dois tipos de probióticos são promissores para adsorverem OTA nas condições simuladas de pH gastrointestinal de tilápias do Nilo, sendo a maior eficiência verificada para o probiótico B.Given the constant contamination of animals by feed mycotoxins, this study aimed to evaluate in vitro the ability of commercial products used in aquaculture as adsorbents of ochratoxin A (OTA). Two comercial probiotics, composed of Bacillus subtilis, Bifidobacterium bifidum, Enterococcus faecium and Lactobacillus acidophilus (Probiotic A) and one made of dry yeast of Saccharomyces cerevisiae from a brewery (Probiotic B) were used in the assay. Phosphate buffered saline solutions (PBS) at pH 1.5 and 7.5 were formulated to simulate the pH of the stomach and intestine of Nile Tilapia (Oreochromis niloticus). The PBS solutions were tested at the two pH (1,5 and 7,5) with the probiotics concentrations of 0%; 25%; 50%; 75% and 100% for a OTA concentration of 1.000 ng.mL-1. The OTA concentrations were added in microtubes for evaluation of adsorption capacity of the probiotics. The OTA detection and quantification were performed by High Performance Liquid Chromatography (HPLC). The final results showed that the probiotics A and B in their maximum concentration were capable of adsorbing OTA in amounts from 13.78 to 76.81 and from 301.48 to 317.54 (ng.mL-1), respectively. The data showed that this two probiotics were very promissimg at adsorbing OTA under simulated gastrointestinal conditions of pH of tilapias, being more efficient the probiotic B.Fil: Escorcio, Raizza Eveline. Universidade Federal Do Piaui.; BrasilFil: Pereyra, Carina Maricel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; ArgentinaFil: Araújo Neves, Josyanne. Instituto Federal do Maranhão; BrasilFil: Calvet, Rodrigo Maciel. Instituto Federal do Maranhão; BrasilFil: Teixeira de Oliveira Santo, Juillet. Universidade Federal Do Piaui.; BrasilFil: Evangelista Lima, Cristiane. Universidade Federal Do Piaui.; BrasilFil: Carvalho Alves, Verbena. Agencia de Defensa Agropecuaria de Paraná; BrasilFil: Sanches Muratori, Maria Christina. Universidade Federal Do Piaui.; Brasi

In vitro evaluation of aflatoxin B1 adsorption by commercial products used in animal feed

: Objetivou‑se avaliar a capacidade de adsorção in vitro de aflatoxina B1 (AFB1 ) por produtos comerciais utilizados na ali‑ mentação animal. Muitas pesquisas estão sendo realizadas para a descontaminação de AFB1 em alimentos. Os produtos comerciais utilizados frequentemente na alimentação de peixes, disponíveis na forma de probióticos, são formados por cepas de bactérias e levedu‑ ras utilizadas na maioria dos ensaios de adsorção de micotoxinas. Foram utilizados três produtos comerciais: A, composto por Bacillus subtilis, Bifidobacterium bifidum, Enterococcus faecium e Lactobacillus acidophilus; B, por leveduras secas de Saccharomyces cerevisiae pro‑ venientes de cervejaria; e C, por Bacillus subtilis, Bacillus licheniformis e Bacillus pumilus. Cinco suspensões da dose máxima reco‑ mendada pelo fabricante de cada produto (0; 25; 50; 75 e 100%) foram testadas contra AFB1 (1000 ng.mL‑1)em microtubos para determinação da capacidade de adsorção. Para simular o pH do estômago e do intestino de tilápias do Nilo (Oreochromis niloticus) foram formuladas soluções tampão fosfato salino (PBS), com pH 1,5 e 7,5; respectivamente. Os microtubos foram introduzidos em uma centrífuga com agitação mecânica, a 37ºC por 1 h e depois centrifugados por 10 min a 14.000 rpm; os sobrenadantes foram quantificados por cromatografia líquida de alta eficiência. Os pro‑ dutos comerciais, nas concentrações máximas, foram capazes de adsorver AFB1 em quantidades de 45,01 a 129,59; 123,90 a 215,59 e 209,98 a 370,73 ng.mL‑1, respectivamente. Concluiu‑se que todos os produtos comerciais analisados adsorvem AFB1 em condições simuladas de pH gastrointestinal e são candidatos potenciais para adsorção de AFB1 para futuros ensaios in vivo.The aim of this study was to evaluate the aflatoxin B1 (AFB1 ) adsorption capacity, in vitro, by commercial products used in animal feed. Many studies are being conducted for the decontamination of aflatoxins in feed. The commercial products destined to fish feed that are available as probiotics and are formed by strains of bacteria and yeasts used in most mycotoxins adsorption assays. Three commercial products were studied: A, consisting of Bacillus subtilis, Bifidobacterium bifidum, Enterococcus faecium and Lactobacillus acidophilus; B, consisting of dry yeast of Saccharomyces cerevisiae from brewery; and C, consisting of Bacillus subtilis, Bacillus licheniformis and Bacillus pumilus. Five suspensions of the maximum dose recommended by the manufacturer of each product (0; 25; 50; 75 and 100%) were tested against AFB1 (1000 ng.mL‑1) in microtubes to determine the adsorption capacity. To simulate the pH of the stomach and intestine of the Nile tilapia (Oreochromis niloticus), phosphate buffered saline solutions (PBS) at pH 1.5 and 7.5, respectively, were formulated. Microtubes were introduced into a centrifuge with mechanical agitation at 37ºC for 1 h and then centrifuged for 10 min at 14.000 rpm; the supernatants were quantified by high‑performance liquid chromatography. The commercial products in the maximum concentration were capable of adsorbing AFB1 in amounts from 45.01 to 129.59; from 123.90 to 215.59; and from 209.98 to 370.73 (ng.mL‑1), respectively. It was concluded that all commercial products, which are added to animal feed, adsorbed AFB1 under simulated gastrointestinal pH conditions and are potential candidates for AFB1 adsorption for future in vivo studies.Fil: Escórcio Pinheiro, Raizza Eveline. Universidade Federal Do Piaui.; BrasilFil: Pereyra, Carina Maricel. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Araújo Neves, Josyanne. Universidade Federal Do Piaui.; BrasilFil: Calvet, Rodrigo Maciel. Universidade Federal Do Piaui.; BrasilFil: Teixeira de Oliveira Santos, Julliet. Universidade Federal Do Piaui.; BrasilFil: Lima, Cristiane Evangelista. Universidade Federal Do Piaui.; BrasilFil: Carvalho Alves, Verbena. Universidade Federal Do Piaui.; BrasilFil: Gomes Pereira, Maria Marlucia. Universidade Federal Do Piaui.; BrasilFil: Muratori, Maria Christina Sanches. Universidade Federal Do Piaui.; Brasi

Search for the standard model Higgs boson decaying to a bbˉb\bar{b} pair in events with no charged leptons and large missing transverse energy using the full CDF data set

We report on a search for the standard model Higgs boson produced in association with a vector boson in the full data set of proton-antiproton collisions at $\sqrt{s} = 1.96$ TeV recorded by the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.45 fb$^{-1}$. We consider events having no identified charged lepton, a transverse energy imbalance, and two or three jets, of which at least one is consistent with originating from the decay of a $b$ quark. We place 95% credibility level upper limits on the production cross section times standard model branching fraction for several mass hypotheses between 90 and $150 \mathrm{GeV}/c^2$. For a Higgs boson mass of $125 \mathrm{GeV}/c^2$, the observed (expected) limit is 6.7 (3.6) times the standard model prediction.Comment: Accepted by Phys. Rev. Let

Search for the standard model Higgs boson decaying to a bb pair in events with one charged lepton and large missing transverse energy using the full CDF data set

We present a search for the standard model Higgs boson produced in association with a W boson in sqrt(s) = 1.96 TeV p-pbar collision data collected with the CDF II detector at the Tevatron corresponding to an integrated luminosity of 9.45 fb-1. In events consistent with the decay of the Higgs boson to a bottom-quark pair and the W boson to an electron or muon and a neutrino, we set 95% credibility level upper limits on the WH production cross section times the H->bb branching ratio as a function of Higgs boson mass. At a Higgs boson mass of 125 GeV/c2 we observe (expect) a limit of 4.9 (2.8) times the standard model value.Comment: Submitted to Phys. Rev. Lett (v2 contains clarifications suggested by PRL

Search for the standard model Higgs boson decaying to a bb pair in events with two oppositely-charged leptons using the full CDF data set

We present a search for the standard model Higgs boson produced in association with a Z boson in data collected with the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.45/fb. In events consistent with the decay of the Higgs boson to a bottom-quark pair and the Z boson to electron or muon pairs, we set 95% credibility level upper limits on the ZH production cross section times the H -> bb branching ratio as a function of Higgs boson mass. At a Higgs boson mass of 125 GeV/c^2 we observe (expect) a limit of 7.1 (3.9) times the standard model value.Comment: To be submitted to Phys. Rev. Let

Combined Tevatron upper limit on gg->H->W+W- and constraints on the Higgs boson mass in fourth-generation fermion models

Report number: FERMILAB-PUB-10-125-EWe combine results from searches by the CDF and D0 collaborations for a standard model Higgs boson (H) in the process gg->H->W+W- in p=pbar collisions at the Fermilab Tevatron Collider at sqrt{s}=1.96 TeV. With 4.8 fb-1 of integrated luminosity analyzed at CDF and 5.4 fb-1 at D0, the 95% Confidence Level upper limit on \sigma(gg->H) x B(H->W+W-) is 1.75 pb at m_H=120 GeV, 0.38 pb at m_H=165 GeV, and 0.83 pb at m_H=200 GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, we exclude at the 95% Confidence Level a standard-model-like Higgs boson with a mass between 131 and 204 GeV.We combine results from searches by the CDF and D0 collaborations for a standard model Higgs boson (H) in the process gg→H→W+W- in pp̅ collisions at the Fermilab Tevatron Collider at √s=1.96  TeV. With 4.8  fb-1 of integrated luminosity analyzed at CDF and 5.4  fb-1 at D0, the 95% confidence level upper limit on σ(gg→H)×B(H→W+W-) is 1.75 pb at mH=120  GeV, 0.38 pb at mH=165  GeV, and 0.83 pb at mH=200  GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, we exclude at the 95% confidence level a standard-model-like Higgs boson with a mass between 131 and 204 GeV.Peer reviewe

Measurement of the difference of CP-violating asymmetries in D0 -> K+K- and D0 ->pi+pi- decays at CDF

We report a measurement of the difference (Delta Acp) between time-integrated CP--violating asymmetries in D0-> K+ K- and D0-> pi+pi- decays reconstructed in the full data set of proton-antiproton collisions collected by the Collider Detector at Fermilab, corresponding to 9.7 fb-1 of integrated luminosity. The strong decay D*+->D0 pi+ is used to identify the charm meson at production as D0 or anti-D0. We measure Delta Acp = [-0.62 +- 0.21 (stat) +- 0.10 (syst)] %, which differs from zero by 2.7 Gaussian standard deviations.This result supports similar evidence for CP violation in charm-quark decays obtained in proton-proton collisions.Comment: Phys. Rev. Lett. 109, 111801 (2012

Toxigenic mycobiota and mycotoxins in shrimp feed

The objective of this study was to identify the toxigenic mycobiota and the occurrence of aflatoxins in shrimp feed products intended for shrimp cultivated in the coastal area of the state of Piauí, Brazil, in three farms ("A", "B" and "C"). The toxigenic capacity of the fungal species isolated was tested for aflatoxins (AF) and ochratoxin A production. The fungal counts of shrimp feed were similar for the "A" and "B" farms at all cultivation phases, collection sites, in closed and opened packages (1.33 to 2.66CFU g-1 log10 -1). The lowest fungal counts were found in feed from "C" farm (0.65CFU g-1 log10 -1) from closed packages. Thirty-four strains of Aspergillus were detected with a greater prevalence of A. flavus. Two strains produced B1, B2, G1 and G2 aflatoxins at concentrations from 0.39 to 0.42ng g-1; 0.18 to 0.27ng g-1; 1.78ng g-1 and 0.09ng g-1 respectively and were classified as atypical A. flavus. Two strains of A. niger aggregate were OTA producers. Fifteen samples (13.88%) presented AFB1 contamination at levels ranging from 0.25ng to 360ng g-1. This study demonstrates the presence of toxigenic fungi in shrimp feed used at different phases of cultivation and farms. Atypical strains of A. flavus were isolated which produced AF B1, B2, G1 and G2 in shrimp feeds. Only AFB1 was detected in the analyzed fee