scholarly journals Application of the Biolog® Identification System for Aflatoxin-Producing Fungi Associated with Maize (Zea mays L.) Contamination in Romania

2020 ◽  
Vol 77 (2) ◽  
pp. 42
Author(s):  
Irina SMEU ◽  
Elena Mirela CUCU ◽  
Alina Alexandra DOBRE ◽  
Hellene CASIAN
Keyword(s):  
Zea Mays L ◽  
Rhizopus Oryzae ◽  
Health Concern ◽  
Enzyme Linked Immunosorbent Assay ◽  
Identification System ◽  
The European Union ◽  
Total Aflatoxin ◽  
Microbial Identification ◽  
European Regulations ◽  
Low Levels

Cereals are very susceptible to fungal attacks. Fungi have a unique biochemical pathway to assimilate a vast array of available substrates and produce toxic secondary metabolites, such as mycotoxins, which represent a clear public health concern. In this context, a maize survey was conducted in order to assess the diversity of mycotoxin-producing fungi. Low levels of total aflatoxins, acceptable by the European Union, were detected in maize samples. A semi-automated Biolog® Microbial Identification System was used for the identification of the fungal strains. Enzyme-linked immunosorbent assay (ELISA) was used for the quantification of total aflatoxins. The results indicated that Fusarium udum and Rhizopus oryzae were the prevalent fungi for the assessed maize samples, while both control and treated samples showed low levels of total aflatoxins, which did not exceed 1.5 μg kg-1. The registered total aflatoxin concentrations were consistent with the European regulations.

scholarly journals Validation of HPLC and Enzyme-Linked Immunosorbent Assay (ELISA) Techniques for Detection and Quantification of Aflatoxins in Different Food Samples

Foods ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 661 ◽  
Author(s):  
Sharaf S. Omar ◽  
Moawiya A. Haddad ◽  
Salvatore Parisi
Keyword(s):  
European Union ◽  
Limit Of Detection ◽  
Food Samples ◽  
Enzyme Linked Immunosorbent Assay ◽  
Human Consumption ◽  
The European Union ◽  
Total Aflatoxin ◽  
Limit Of Quantification ◽  
Coffee Beans ◽  
Almost All

Background: In Jordan as in other worldwide countries, mycotoxins are considered a serious national problem in food supplies. As a result, almost all nations are setting and adopting different regulations targeting the control of mycotoxins levels in the domestic food supply, including the problem of reliable sampling and analysis methods. Objective: It is necessary to improve and give evidence of analytical abilities of laboratories within Jordan and developing countries enabling them to monitor mycotoxins effectively in food to overcome non-tariff obstacles. Methods: We analyzed 40 samples from wheat, corn, dried fig and dried coffee beans for total aflatoxin content using High Pressure Liquid Chromatography (HPLC) and Enzyme Linked Immunesorbent Assay (ELISA) methods. Results: 40% of samples from wheat, 60% from corn, 30% from dried fig, and 50% from dried coffee beans were found positive when speaking of total aflatoxins, with average values between 1.14 and 4.12 μg/kg. Obtained results allow considering all tested food samples as fit for human consumption if compared with the labeled regulatory limit of allowed aflatoxins in the European Union. In detail, the limit of detection and the limit of quantification for methods used in this study were significantly lower than the maximum limits established by the European Union. Highlights: The procedure used in this study is suitable for detection of mycotoxins at very low concentration.

scholarly journals Natural Outbreak of a Bacterial Fruit Rot of Cantaloupe in Georgia Caused by Acidovorax avenae subsp. citrulli

Plant Disease ◽  
2000 ◽  
Vol 84 (3) ◽  
pp. 372-372 ◽  
Author(s):  
R. R. Walcott ◽  
D. B. Langston ◽  
F. H. Sanders ◽  
R. D. Gitaitis ◽  
J. T. Flanders
Keyword(s):  
Tween 80 ◽  
Soft Rot ◽  
Fatty Acid Analysis ◽  
Fruit Rot ◽  
Enzyme Linked Immunosorbent Assay ◽  
Identification System ◽  
Microbial Identification ◽  
Leaf Tissues ◽  
Different Sources ◽  
Natural Outbreak

In April and July 1999, cantaloupe plants (Cucumis melo) from commercial greenhouses and fields in Grady, Colquitt, Mitchell, and Tift counties, GA, exhibited severe foliar necrosis and a fruit rot. Foliar symptoms were V-shaped, necrotic lesions occurring at the margin of the leaf and extending inward toward the midrib. Symptoms on the fruit surface were observed after net development and occurred randomly as round, necrotic, sunken spots or cracks a few millimeters in diameter. A soft rot originating from lesions on the surface of the fruit expanded into the flesh. Approximately 5% of the fruits were affected. Bacteria recovered from cantaloupe fruit and leaf tissues produced nonfluorescent, smooth, off-white colonies on King's medium B. Characteristic of Acidovorax avenae subsp. citrulli, the bacteria produced pits in carboxymethyl cellulose media (WFB 44), and reduced Tween 80 to give a visible precipitate on WFB 68 media (1). Based on fatty acid analysis, all strains were identified as A. avenae subsp. citrulli by Microbial Identification System software, version 3.6 (MIDI, Newark, DE), and similarity indices of 0.06, 0.79, 0.21, and 0.43 were recorded for strains recovered form Grady, Tift, Colquitt, and Mitchell counties, respectively. Using specific oligonucleotide primers (WFB 1/2) (2), PCR conducted on DNA from each strain yielded a 390-bp DNA fragment, confirming similarity to A. avenae subsp. citrulli. Indirect enzyme-linked immunosorbent assay with genus-specific antibodies also verified that the bacteria were Acidovorax spp. Pathogenicity of the A. avenae subsp. citrulli strains was confirmed by inoculating and observing symptom development on 2-week-old watermelon seedlings. Although all strains were identified and confirmed as A. avenae subsp. citrulli, restriction fragment length polymorphism data indicated that the Tift County strain was distinguishable from the others, suggesting that inoculum for these outbreaks may have originated from at least two different sources. References: (1) R. D. Gitaitis. 1993. Development of a seedborne assay for watermelon fruit botch. Pages 9–18 in: Proc. 1st Int. Seed Testing Assoc. Plant Dis. Commit., Ottawa, Canada. (2) R. R. Walcott and R. D. Gitaitis. (Abstr.) Phytopathology 88(suppl.):S92, 1998.

scholarly journals Detection of Aflatoxin in Poultry Feed and Feed Materials through Immuno Based Assay from Different Poultry Farms and Feed Factories in Bangladesh

2019 ◽  
Vol 35 (1) ◽  
pp. 75-78 ◽  
Author(s):  
Mahbuba Akter Lubna ◽  
Mita Debnath ◽  
Farzana Hossaini
Keyword(s):  
Health Risk ◽  
Positive Result ◽  
Mean Value ◽  
Aflatoxin Contamination ◽  
Control Measures ◽  
Poultry Feed ◽  
Enzyme Linked Immunosorbent Assay ◽  
Total Aflatoxin ◽  
Poultry Farms ◽  
Aflatoxin Concentration

Current study investigated the occurrence of aflatoxin contamination in poultry feed and feed materials in different poultry farms and feed factories in Bangladesh. A total of 100 samples of finished feed and raw feed materials were collected and tested through direct competitive Enzyme-Linked Immunosorbent Assay (ELISA) for total aflatoxin detection. Overall, 97% samples (n=97/100) in our study, were found positive for aflatoxin contamination. Among finished feed categories, layer grower feed contained highest level of aflatoxin with a mean value of 21.64 ppb whereas layer feed was less susceptible for aflatoxin contamination (mean value 9.49 ppb). Between raw feed materials, maize samples were highly contaminated (n=15/15, 100%) with aflatoxin while 86.67% soybean samples showed positive result. Twenty one percent (21%) of the samples in our study contained aflatoxin concentration more than the acceptable limit employed by USFDA and many other countries which might pose severe health risk to poultry and human consumer. Proper surveillance and immediate control measures should be taken to ensure safe poultry feed and feed materials. Bangladesh J Microbiol, Volume 35 Number 1 June 2018, pp 75-78

scholarly journals Bioanalytical screening of low levels of dioxins and dioxin-like PCBs in pig meat (pork) for checking compliance with EU maximum and action levels using highly sensitive “third generation” recombinant H4L7.5c2 rat hepatoma cells

2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Johannes Haedrich ◽  
Claudia Stumpf ◽  
Michael S. Denison
Keyword(s):  
European Union ◽  
Hepatoma Cell ◽  
Animal Origin ◽  
The European Union ◽  
Highly Sensitive ◽  
Commission Regulation ◽  
Pig Meat ◽  
Low Levels ◽  
Action Levels ◽  
Rat Hepatoma

Abstract Background Low maximum and action levels set by the European Union for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in pig meat (pork) have led to a demand for reliable and cost-effective bioanalytical screening methods implemented upstream of gas chromatography/high-resolution mass spectrometry confirmatory technology, that can detect low levels of contamination in EU-regulated foods with quick turn-around times. Results Based on the Chemically Activated LUciferase gene eXpression (CALUX) bioassay, extraction and clean-up steps were optimized for recovery and reproducibility within working ranges significantly lower than in current bioassays. A highly sensitive “3rd generation” recombinant rat hepatoma cell line (H4L7.5c2) containing 20 dioxin responsive elements was exposed to pork sample extracts, and their PCDD/Fs and DL-PCBs levels were evaluated by measuring luciferase activity. The method was validated according to the provisions of Commission Regulation (EU) 2017/644 of 5 April 2017 with spiking experiments performed selectively for PCDD/Fs and DL-PCBs and individual calibration for PCDD/Fs, DL-PCBs and the calculated sum of PCDD/Fs and DL-PCBs. The resulting performance parameters met all legal specifications as confirmed by re-calibration using authentic samples. Cut-off concentrations for assessing compliance with low maximum levels and action levels set for PCDD/Fs and DL-PCBs within a range of 0.50–1.25 pg WHO-TEQ/g fat were derived, ensuring low rates of false-compliant results (ß-error < 1%) and keeping the rate of false-noncompliant results well under control (α-error < 12%). Conclusions We present a fast and efficient bioanalytical routine method validated according to the European Union’s legal requirements on the basis of authentic samples, allowing the analyst to reliably identify pork samples and any other EU-regulated foods of animal origin suspected to be noncompliant with a high level of performance and turn-around times of 52 h. This was facilitated in particular by a quick and efficient extraction step followed by selective clean-up, use of a highly sensitive “3rd generation” H4L7.5c2 recombinant rat hepatoma cell CALUX bioassay, and optimized assay performance with improved calibrator precision and reduced lack-of-fit errors. New restrictions are proposed for the calibrator bias and the unspecific background contribution to reportable results. The procedure can utilize comparably small sample amounts and allows an annual throughput of 840–1000 samples per lab technician. The described bioanalytical method contributes to the European Commission's objective of generating accurate and reproducible analytical results according to Commission Regulation (EU) 2017/644 across the European Union.

scholarly journals Seroprevalence of Toxoplasma gondii and associated risk factors in domestic pigs raised from Cuba

2021 ◽  
Author(s):  
Julio César Castillo-Cuenca ◽  
Álvaro Martínez-Moreno ◽  
José Manuel Diaz-Cao ◽  
Angel Entrena-García ◽  
Jorge Fraga ◽  
...  
Keyword(s):  
Risk Factors ◽  
Toxoplasma Gondii ◽  
Meat Products ◽  
Control Measures ◽  
Health Concern ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Cross Sectional ◽  
Weaning Pigs ◽  
Associated Risk Factors

AbstractA cross-sectional study was carried out to determine the seroprevalence of Toxoplasma gondii and associated risk factors in pigs in the largest pork-producing region in Cuba. Serum samples from 420 pigs, including 210 sows and 210 post-weaning pigs, were tested for antibodies against T. gondii using a commercial indirect enzyme-linked immunosorbent assay. Anti-T. gondii antibodies were detected in 56 animals (13.3%, 95% CI: 10.1–16.6). A generalized estimating equations model revealed that the risk factors associated with higher seropositivity in pigs were altitude (higher in farm’s location < 250 m above sea level (masl) versus ≥ 250 masl) and age (higher in sows compared to post-weaning pigs). The results indicated that this protozoan parasite is widely distributed on pig farms in the study area, which is a public health concern since the consumption of raw or undercooked pork meat products containing tissue cysts is considered one of the main routes of T. gondii transmission worldwide. Control measures should be implemented to reduce the risk of exposure to T. gondii in pigs in Cuba.

scholarly journals Identification of Three Strains of Mycobacterium Species Isolated from Clinical Samples Using Fatty Acid Methyl Ester Profiling

2003 ◽  
Vol 31 (2) ◽  
pp. 133-140 ◽  
Author(s):  
A Ozbek ◽  
O Aktas
Keyword(s):  
Fatty Acid ◽  
Methyl Esters ◽  
Acid Methyl Ester ◽  
Cellular Fatty Acid ◽  
Clinical Samples ◽  
Identification System ◽  
Cyclopropane Fatty Acid ◽  
Mycobacterium Species ◽  
Microbial Identification ◽  
Acid Methyl

The cellular fatty acid profiles of 67 strains belonging to three different species of the genus Mycobacterium were determined by gas chromatography of the fatty acid methyl esters, using the MIDI Sherlock® Microbial Identification System (MIS). The species M. tuberculosis, M. xenopi and M. avium complex were clearly distinguishable and could be identified based on the presence and concentrations of 12 fatty acids: 14:0, 15:0, 16:1ω7c, 16:1ω6c, 16:0, 17:0, 18:2ω6,9c, 18:1ω9c, 18:0, 10Me-18:0 tuberculostearic acid, alcohol and cyclopropane. Fatty acid analysis showed that there is great homogeneity within and heterogeneity between Mycobacterium species. Thus the MIS is an accurate, efficient and relatively rapid method for the identification of mycobacteria.

Occurrence of Ochratoxin A Contamination and Detection of Ochratoxigenic Aspergillus Species in Retail Samples of Dried Fruits and Nuts

2015 ◽  
Vol 78 (4) ◽  
pp. 836-842 ◽  
Author(s):  
JEFFREY D. PALUMBO ◽  
TERESA L. O'KEEFFE ◽  
YVONNE S. HO ◽  
CARLO J. SANTILLAN
Keyword(s):  
European Union ◽  
Ochratoxin A ◽  
The United States ◽  
Aspergillus Species ◽  
The European Union ◽  
Dried Fruits ◽  
Tree Nuts ◽  
Low Levels ◽  
Contamination Levels ◽  
Potential Contaminant

Ochratoxin A (OTA) is a mycotoxin produced by several species of Aspergillus and Penicillium and is a potential contaminant of a wide variety of food products. To determine the incidence of OTA contamination in dried fruits and tree nuts, retail packaged and bulk raisins, dates, figs, prunes, almonds, pistachios, and walnuts were collected from small and large supermarkets in seven areas of the United States between 2012 and 2014. Of the 665 samples analyzed, OTA was detected in 48 raisin samples, 4 fig samples, 4 pistachio samples, and 1 date sample. OTA contamination levels ranged from 0.28 to 15.34 ng/g in dried fruits and 1.87 to 890 ng/g in pistachios; two raisin samples and one pistachio sample exceeded the European Union regulatory limit of 10 ng/g. PCR detection of potential OTA-producing Aspergillus species revealed the presence of A. niger, A. welwitschiae, and A. carbonarius in 20, 7, and 7 of the 57 OTA-contaminated samples, respectively. However, OTA-producing A. carbonarius was isolated from only one raisin sample, and no other OTA-producing Aspergillus species were found. These results suggest that raisins are more frequently contaminated with low levels of OTA than are other dried fruits and nuts and that Aspergillus species are the likely source of that contamination.

scholarly journals Development and evaluation of an in-house ELISA to detect hepatitis B virus surface antigen in resource-limited settings

2014 ◽  
Vol 39 (2) ◽  
pp. 65-68 ◽  
Author(s):  
K Fatema ◽  
S Tabassum ◽  
A Nessa ◽  
M Jahan
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Surface Antigen ◽  
Hbv Infection ◽  
Health Concern ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Surface ◽  
B Virus ◽  
Commercial Kits ◽  
Checkerboard Titration

Hepatitis B virus (HBV) infection is of global public health concern. Among various serological tests used for the diagnosis and screening of HBV infection, the enzyme-linked immunosorbent assay (ELISA) to detect hepatitis B surface antigen (HbsAg) is most widely used. The present study was designed to develop and standardize a cost effective in-house ELISA for the detection of HbsAg and compare its performance with two established commercial kits. The concentrations of coating antibody, conjugates and sera were fixed by checkerboard titration. Using known HBsAg positive and negative sera, four different concentrations (1, 0.5, 0.25 and 0.125 ?g/well) of coating anti-HBs were applied. Similarly, serial dilutions of patients’ sera (1 in 2, 1 in 3, 1 in 5 and 1 in 9) and conjugates (1 in 2, 1 in 3, 1 in 5, 1 in 9 and 1 in 17) were evaluated by checkerboard titration. The optimal concentration of coating antibody was determined at 0.25 ?g/well and 1 in 9 dilution for both conjugates and sera. The performance comparison of our in-house ELISA showed excellent correlation with two commercial kits (Pearson 0.957, P=0.001 for monoclonal antibody coated kit and Pearson 0.929, P=0.000 for polyclonal antibody coated kit) when OD values were compared. All commercial kit proven positive samples was positive while all negative samples were negative with the in-house ELISA resulting in 100% sensitivity and specificity. The results of our study demonstrated that our inhouse ELISA for detection of HBsAg was equally as sensitive and specific as two well-known commercial kits. Thus, this system may be a useful tool for diagnostic and screening purposes, as well as outbreak investigations. DOI: http://dx.doi.org/10.3329/bmrcb.v39i2.19644 Bangladesh Med Res Counc Bull 2013; 39: 65-68

The first study on the bacterial flora of the european spruce bark beetle, Dendroctonus micans (Coleoptera: Scolytidae)

Biologia ◽  
2006 ◽  
Vol 61 (6) ◽  
Author(s):  
Hüseyin Yilmax ◽  
Kazım Sezen ◽  
Hatice Kati ◽  
Zihni Demirbağ
Keyword(s):  
Bark Beetle ◽  
Micrococcus Luteus ◽  
Bacterial Flora ◽  
Biochemical Properties ◽  
Identification System ◽  
Dendroctonus Micans ◽  
Microbial Identification ◽  
Spruce Bark Beetle ◽  
Spruce Bark ◽  
European Spruce Bark Beetle

AbstractThe European spruce bark beetle, Dendroctonus micans Kugelann (Coleoptera, Scolytidae), is one of the most serious pests of oriental spruce (Picea orientalis L.) in Turkey. In this study, we investigated bacterial flora of D. micans collected from different populations of the forests of Eastern Black Sea Region of Turkey from 2002 to 2004. Seven different bacteria were isolated from healthy, diseased and dead specimens based on the color of colony and morphology. According to morphological, physiological and biochemical properties, metobolic enyzme profile by BIOLOG microtiter plate system, and total cellular fatty acid profile by Microbial Identification System (MIS), isolates were identified as Micrococcus luteus, Bacillus thuringiensis subsp. morrisoni, Serratia grimesii, Enterobacter cloaceae, Enterobacter intermedius, Streptococcus sp. and Pseudomonas putida. This is the first study on the bacterial flora of D. micans.

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