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Aflatoxin Contamination (aflatoxin + contamination)
Selected AbstractsDETERMINATION OF AFLATOXIN CONTAMINATION IN OLIVES BY IMMUNOAFFINITY COLUMN USING HIGH-PERFORMANCE LIQUID CHROMATOGRAPHYJOURNAL OF FOOD QUALITY, Issue 2 2006CAVIT BIRCAN ABSTRACT Eighty-two whole black olive samples gathered from six different olive oil processing facilities were surveyed to determine levels of aflatoxins using immunoaffinity column extraction and reversed-phase high-performance liquid chromatography. Two different analytical procedures adopted for the analysis of aflatoxins were investigated for their suitability by spiking the blank olive samples with five different known levels of aflatoxins to determine which one had higher recovery rates. Although some of the olive samples had been exposed to adverse conditions, such as rain and high temperatures, none were found to contain aflatoxins at the determined detection limit. Although the samples were kept in high relative humidity (75%) and high temperature (30C) for 3 months and were tested at 1-month intervals, no aflatoxins were detected. In addition, the olives were inoculated on a potato dextrose agar medium and incubated for 7 days at 25C to characterize the microflora. Because there is no evidence of aflatoxins in fresh whole olives, the next step of processing the contaminated olives into olive oils and testing them for the aflatoxins was not pursued. [source] Essential Oil of,Aegle marmelos,as a Safe Plant-Based Antimicrobial Against Postharvest Microbial Infestations and Aflatoxin Contamination of Food CommoditiesJOURNAL OF FOOD SCIENCE, Issue 6 2009Priyanka Singh ABSTRACT:, The essential oil of,Aegle marmelos,L. Correa (Rutaceae) showed strong fungitoxicity against some storage fungi-causing contamination of foodstuffs. The oil also showed efficacy as aflatoxin suppressor at 500 ,L/L as it completely arrested the aflatoxin B1 production by the toxigenic strains (Navjot 4NSt and Saktiman 3NSt) of,Aspergillus flavus,Link. Keeping in view the side effects of synthetic fungicides,,A. marmelos,oil may be recommended as an antimicrobial of plant origin to enhance the shelf life of stored food commodities by controlling the fungal growth as well as aflatoxin secretion. This is the 1st report on aflatoxin B1 inhibitory nature of this oil.,A. marmelos,oil may be recommended as a novel plant-based antimicrobial in food protection over synthetic preservatives, most of which are reported to incite environmental problems because of their nonbiodegradable nature and side effects on mammals. The LD50 of,Aegle,oil was found to be 23659.93 mg/kg body weight in mice (Mus musculus,L.) when administered for acute oral toxicity showing nonmammalian toxicity of the oil. GC-MS analysis of the oil found DL-Limonene to be major component. [source] Drought Stress and Preharvest Aflatoxin Contamination in Agricultural Commodity: Genetics, Genomics and ProteomicsJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 10 2008Baozhu Guo Abstract Throughout the world, aflatoxin contamination is considered one of the most serious food safety issues concerning health. Chronic problems with preharvest aflatoxin contamination occur in the southern US, and are particularly troublesome in corn, peanut, cottonseed, and tree nuts. Drought stress is a major factor to contribute to preharvest aflatoxin contamination. Recent studies have demonstrated higher concentration of defense or stress-related proteins in corn kernels of resistant genotypes compared with susceptible genotypes, suggesting that preharvest field condition (drought or not drought) influences gene expression differently in different genotypes resulting in different levels of "end products": PR(pathogenesis-related) proteins in the mature kernels. Because of the complexity of Aspergillus -plant interactions, better understanding of the mechanisms of genetic resistance will be needed using genomics and proteomics for crop improvement. Genetic improvement of crop resistance to drought stress is one component and will provide a good perspective on the efficacy of control strategy. Proteomic comparisons of corn kernel proteins between resistant or susceptible genotypes to Aspergillus flavus infection have identified stress-related proteins along with antifungal proteins as associated with kernel resistance. Gene expression studies in developing corn kernels are in agreement with the proteomic studies that defense-related genes could be upregulated or downregulated by abiotic stresses. [source] Aflatoxin contamination of consumer milk caused by contaminated rice by-products in compound cattle feedJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2009Erik Nordkvist Abstract BACKGROUND: Elevated levels of aflatoxin M1 were observed in routine checks of consumer milk in southern Sweden in early 2006. A trace-back study revealed contaminated milk from several farms, and a total of 68 farms were banned from delivering milk to dairies for shorter or longer periods. The maximum level of aflatoxin M1 in a single sample from an individual farm was 257 ng kg,1 fresh milk. RESULTS: Aflatoxin analyses of commercial compound feed revealed that the contamination originated from the ingredient rice feed meal, a by-product from the preparation of Basmati rice for human consumption. Up to 56 µg kg,1 of aflatoxin B1 was found in rice feed meal at one feed mill. CONCLUSION: The present example shows that an aflatoxin-contaminated minor feed ingredient included at less than 10% (w/w) of compound cattle feed can significantly contaminate the milk produced. This emphasises the need for effective monitoring of the feed chain of food-producing animals in order to prevent food contamination. Copyright © 2008 Society of Chemical Industry [source] The determination of aflatoxins in spices by immunoaffinity column extraction using HPLCINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2005Cavit Bircan Summary Seventy-five samples of different spices marketed in Turkey were purchased from bazaars, herbal shops and supermarkets. Equal amounts of paprika, chilli, black peppers and cumin were purchased and used to test and compare the amount of aflatoxin contamination. Two different analytical methods were examined for their efficacy by adding a known amount of aflatoxin to the blank samples of paprika. Twenty-seven paprika, all the chilli powder and four ground black pepper samples were contaminated with aflatoxin B1 in the range of 0.5,116.4, 1.6,80.4 and 0.3,1.2 ,g kg,1 respectively. Twenty-three (30%) paprika and chilli powder samples were above the regulatory limits used in the European Union. No aflatoxin contamination was detected in the cumin samples at a detection limit of 0.2 ,g kg,1. [source] The use of powder and essential oil of Cymbopogon citratus against mould deterioration and aflatoxin contamination of ,egusi' melon seedsJOURNAL OF BASIC MICROBIOLOGY, Issue 1 2005S. A. Bankole Dr. Experiments were carried out to determine the potential of using the powder and essential oil from dried ground leaves of Cymbopogon citratus (lemon grass) to control storage deterioration and aflatoxin contamination of melon seeds. Four mould species: Aspergillus flavus, A. niger, A. tamarii and Penicillium citrinum were inoculated in the form of conidia suspension (approx. 106 conidia per ml) unto shelled melon seeds. The powdered dry leaves and essential oil from lemon grass were mixed with the inoculated seeds at levels ranging from 1,10 g/100 g seeds and 0.1 to 1.0 ml/100 g seeds respectively. The ground leaves significantly reduced the extent of deterioration in melon seeds inoculated with different fungi compared to the untreated inoculated seeds. The essential oil at 0.1 and 0.25 ml/100 g seeds and ground leaves at 10 g/100 g seeds significantly reduced deterioration and aflatoxin production in shelled melon seeds inoculated with toxigenic A. flavus. At higher dosages (0.5 and 1.0 ml/100 g seeds), the essential oil completely prevented aflatoxin production. After 6 months in farmers' stores, unshelled melon seeds treated with 0.5 ml/ 100 g seeds of essential oil and 10 g/100 g seeds of powdered leaves of C. citratus had significantly lower proportion of visibly diseased seeds and Aspergillus spp. infestation levels and significantly higher seed germination compared to the untreated seeds. The oil content, free fatty acid and peroxide values in seeds protected with essential oil after 6 months did not significantly differ from the values in seeds before storage. The efficacy of the essential oil in preserving the quality of melon seeds in stores was statistically at par with that of fungicide (iprodione) treatment. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Drought Stress and Preharvest Aflatoxin Contamination in Agricultural Commodity: Genetics, Genomics and ProteomicsJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 10 2008Baozhu Guo Abstract Throughout the world, aflatoxin contamination is considered one of the most serious food safety issues concerning health. Chronic problems with preharvest aflatoxin contamination occur in the southern US, and are particularly troublesome in corn, peanut, cottonseed, and tree nuts. Drought stress is a major factor to contribute to preharvest aflatoxin contamination. Recent studies have demonstrated higher concentration of defense or stress-related proteins in corn kernels of resistant genotypes compared with susceptible genotypes, suggesting that preharvest field condition (drought or not drought) influences gene expression differently in different genotypes resulting in different levels of "end products": PR(pathogenesis-related) proteins in the mature kernels. Because of the complexity of Aspergillus -plant interactions, better understanding of the mechanisms of genetic resistance will be needed using genomics and proteomics for crop improvement. Genetic improvement of crop resistance to drought stress is one component and will provide a good perspective on the efficacy of control strategy. Proteomic comparisons of corn kernel proteins between resistant or susceptible genotypes to Aspergillus flavus infection have identified stress-related proteins along with antifungal proteins as associated with kernel resistance. Gene expression studies in developing corn kernels are in agreement with the proteomic studies that defense-related genes could be upregulated or downregulated by abiotic stresses. [source] AFLP Analysis of Trichoderma spp. from India Compared with Sequence and Morphological-based DiagnosticsJOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2005H. K. Buhariwalla Abstract Trichoderma species offer considerable potential for controlling aflatoxin contamination in groundnut and other crops. Initial classification of 48 Trichoderma isolates, derived from four different groundnut cultivation sites in India was based on alignment of 28S rDNA sequences to GenBank sequences of ex-type strains. This was found to be substantially more reliable than our routine morphological characterization, but did not provide a comprehensive diagnostic solution, as unique single nucleotide polymorphism (SNP) haplotypes could not be identified for all species. However, all the Trichoderma isolates could be readily distinguished by amplified fragment length polymorphism (AFLP) analysis, based on six primer pair combinations, which generated 234 polymorphic bands. In addition, individual AFLP bands were identified which differentiate closely related species. Similarly, AFLP bands were identified that correlated with different types of antagonism to Aspergillus flavus. The implications of these results for the development of simple polymerase chain reaction (PCR)-based diagnostic assays for antagonistic isolates of Trichoderma is discussed. [source] The effect of delayed harvest on moisture content, insect damage, moulds and aflatoxin contamination of maize in Mayuge district of UgandaJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2005Archileo N Kaaya Abstract Field drying is a traditional practice carried out by farmers in Uganda and it is one of those practices reported to affect the postharvest quality of maize. A study was therefore conducted to establish the effects of delayed harvest on moisture content, insect damage, moulds and aflatoxin contamination of maize in Mayuge district. Sixteen farmers were selected from Bayitambogwe sub-county, eight from each of the villages of Bugodi and Musita. Maize was sampled from each farmer's field in 2003B and 2004A seasons at harvest stages of physiological maturity and after delayed harvest for 1, 2, 3 and 4 weeks. Each sample was analysed for mould incidence, moisture content, insect damage and aflatoxin contamination. In each season, mould incidence, insect damage and aflatoxin levels significantly (P < 0.05) increased with delayed time of harvest. Moisture content reduced with delayed harvest time but the maize did not dry to the required safe storage moisture content of ,15%. Seasonal effects were only significant for moisture content: the 2003B crop had consistently lower moisture content than 2004A crop. These results indicate that, for improved harvest quality of maize, farmers should harvest no later than 3 weeks after maize has attained physiological maturity. Copyright © 2005 Society of Chemical Industry [source] | |||||||||||||