Survey Of Aflatoxins In Tomato Products [aflatoxinas Em Produtos De Tomate]

Tomatoes are highly susceptible to fungi contamination in the field, during transportation, processing, and storage. Aspergillus flavus and Aspergillus parasiticus have been isolated from tomatoes and tomato products, and both fungi species can produce aflatoxin, mycotoxin with hepatotoxic, carcinogenic, teratogenic, and mutagenic effects on all animal species tested so far. In order to verify a possible aflatoxin contamination of tomato products commercialized in Brazil, 63 samples of tomato products (pulp, paste, purée, ketchup, dehydrated tomatoes, and dried tomatoes preserved in oil) produced in 5 Brazilian states and 1 imported sample (ketchup), totalizing 29 brands, were analyzed by thin layer chromatography. The analytical method showed an average recovery of 86% for all aflatoxins at two spiking levels. The limits of detection for the aflatoxins B1, B2, G1, and G2 varied with the type of the product ranging from 2 to 7 μg/kg. Aflatoxins were not detected in any evaluated sample indicating that they did not pose a risk to human health since there was no invasion of raw materials by toxigenic fungi or no conditions for toxin production.292431434(1998) Official Methods of Analysis. Method 970.44. 16 ed, , ASSOCIATION OF OFFICIAL ANALYTICAL CHEMISTS - AOAC, Gaithersburg, EUAAyres, J.C., Kraft, A.A., Pierce, L.C., Delaying spoilage of tomatoes (1964) Food Technology, 18 (8), pp. 100-103A agricultura brasileira em números (2005) Estatística - Anuário, , http://www.agricultura.gov.br/portal/page?_pageid=33,2789141&_dad=po rtal&_schema=PORTAL, BRASIL. Ministério da Agricultura, Pecuária e Abastecimento, In:, Disponível em:, Acesso em: 6 de Outubro de 2007Busby Jr,, W.F., Wogan, G.N., Aflatoxins (1981) Mycotoxins and N-nitroso compounds: Environmental risks, pp. 3-28. , In: SHANK, R. C. (Ed.)., E.U.A: CRC PressEhrlich, K.C., Aflatoxin-producing Aspergillus species from Thailand (2007) International Journal of Food Microbiology, 114 (2), pp. 153-159Frisvad, J.C., Skouboe, P., Samson, R.A., Taxonomic comparison of three different groups of aflatoxin producers and a new efficient producer of aflatoxin B-1, sterigmatocystin and 3-O-methylsterigmatocystin, Aspergillus rambellii sp nov (2005) Systematic and Applied Microbiology, 28 (5), pp. 442-453Gelosa, L., La ricerca delle mico'tossine in un laboratorio di sanità pubblica (1983) Industrie Alimentari, 22 (3), pp. 175-178Gourama, H., Bullerman, L.B., Aspergillus flavus and Aspergillus parasiticus: Aflatoxigenic fungi of concern in foods and feeds: A review (1995) Journal of Food Protection, 58 (12), pp. 1395-1404Gourama, H., Inhibition of growth and mycotoxin production of penicillium by Lactobacillus species (1997) LWT - Food Science and Technology, 3, pp. 279-283. , v.3Harwig, J., Toxins of molds from decaying tomato fruit (1979) Applied and Environmental Microbiology, 38 (2), pp. 267-274Hua, S.S.T., Grosjean, O.K., Baker, J.L., Inhibition of aflatoxin biosynthesis by phenolic compounds (1999) Letters in Applied Microbiology, 29 (5), pp. 289-291Ito, Y., Aspergillus pseudotamarii, a new aflatoxin producing species in Aspergillus section Flavi (2001) Mycological Research, 105 (2), pp. 233-239Kawashima, L.M., Soares, L.M.V., Massaguer, P.R., The development of an analytical method for two mycotoxins, patulin and verruculogen, and survey of their presence in commercial tomato pulp (2002) Brazilian Journal of Microbiology, 33 (3), pp. 269-273Kenjo, T., Fungal population and distribution of aflatoxigenic fungi in commercial almond powder products (2007) Journal of the Food Hygienics Society of Japan, 48 (4), pp. 90-96Kheiralla, Z.H., Hassanin, N.I., Amra, H., Effect of incubation- time, temperature and substrate on growth and aflatoxin production (1992) International Biodeterioration and Biodegradation, 30 (1), pp. 17-27Lucisano, A., Campanini, M., Casolari, A., Contributo allo studio ambientali che condizionano la produzione di aflatossine negli alimenti (1972) Industria Conserve, 47 (1), pp. 27-31Mallozzi, M.A.B., Effect of flavonoids on Aspergillus flavus growth and aflatoxin production (1996) Revista de Microbiologia, 27 (2), pp. 161-165Marasas, W.F.O., Nelson, P.E., (1987) Mycotoxicology., , 1 ed, E.U.A.: The Pennsylvania State University PressMartínez-Valverde, I., Phenolic compounds, lycopene and antioxidant activity in commercial varieties of tomato (Lycopersicum esculentum) (2002) Journal of the Science of Food Agriculture, 82 (4), pp. 323-330Mislivec, P.B., Molds and tenuazonic acid in fresh tomatoes used for catsup production (1987) Journal of Food Protection, 50 (1), pp. 38-41Motta, S., Soares, L.M.V., Survey of Brazilian tomato products for alternariol, alternariol monomethyl ether, tenuazonic acid, and cyclopiazonic acid (2001) Food Additives and Contaminants, 18 (7), pp. 630-634Muhammad, S., Shehu, K., Amusa, N.A., Survey of the market diseases and aflatoxin contamination of tomato (Lycopersicon esculentum MILL) fruits in Sokoto, northwestern Nigeria (2004) Nutrition and Food Science, 34 (2), pp. 72-76Mutti, P., Dellapina, G., Spotti, E., Produzione, stabilità, diffusione, screening di aflatossine in derivati del pomodoro (1992) Industria Conserve, 67 (1), pp. 39-41Northolt, M.D., Vanegmond, H.P., Paulsch, W.E., Differences between Aspergillus-flavus strains in growth and aflatoxin-b1 production in relation to water activity and temperature (1977) Journal of Food Protection, 40 (11), pp. 778-781Obeta, J.A.N., Ugwuanyi, J.O., Heat-resistant fungi in Nigerian heat-processed fruit juices (1995) International Journal of Food Science and Technology, 30 (5), pp. 587-590Oladiran, A.O., Iwu, L.N., Studies on the fungi associated with tomato fruit rots and effects of environment on storage (1993) Mycopathologia, 121 (3), pp. 157-161Pearson, R.C., Hall, D.H., Factors affecting the occurrence and severity of blackmold of ripe tomato fruit caused by Alternaria alternata (1975) Phytopathology, 65 (12), p. 1359Peterson, S.W., Aspergillus bombycis, a new aflatoxigenic species and genetic variation in its sibling species, A-nomius (2001) Mycologia, 93 (4), pp. 689-703Pitt, J.I., Miscamble, B.F., Water relations of Aspergillus flavus and closely related species (1995) Journal of Food Protection, 58 (1), pp. 86-90Ramakrishna, N., Lacey, J., Smith, J.E., Aspergillus flavus colonization and aflatoxin B-1 formation in barley grain during interaction with other fungi (1996) Mycopathologia, 136 (1), pp. 53-63Scott, P.M., Kanhere, S.R., Liquid chromatographic of tenuazonic acids in tomato paste (1980) Journal of the Association of Official Analytical Chemists, 63 (3), pp. 612-621Soares, L.M.V., Rodriguez-Amaya, D.B., Survey of aflatoxins, ochratoxin A, zearalenone, and sterigmatocystin in some Brazilian foods, utilizing a multi-toxin thin layer chromatographic method (1989) Journal of the Association of Official Analytical Chemists, 72 (1), pp. 22-26Stack, M.E., Liquid-chromatographic determination of tenuazonic acid and alternariol methyl ether in tomatoes and tomato products (1985) Journal of the Association of Official Analytical Chemists, 68 (4), pp. 640-642Trucksess, M.W., Stoloff, L., Mislivec, P.B., Effect of temperature, water activity and other toxigenic mold species on growth of aspergillus-flavus and aflatoxin production on corn, pinto beans and soybeans (1988) Journal of Food Protection, 51 (5), pp. 361-36

Bacterial strains from floodplain soils perform different plant-growth promoting processes and enhance cowpea growth

ABSTRACT Certain nodulating nitrogen-fixing bacteria in legumes and other nodule endophytes perform different plant-growth promoting processes. The objective of this study was to evaluate 26 bacterial strains isolated from cowpea nodules grown in floodplain soils in the Brazilian savannas, regarding performance of plant-growth promoting processes and ability to enhance cowpea growth. We also identified these strains by 16S rRNA sequencing. The following processes were evaluated: free-living biological nitrogen fixation (BNF), solubilization of calcium, aluminum and iron phosphates and production of indole-3-acetic acid (IAA). The abilities to nodulate and promote cowpea growth were evaluated in Leonard jars. Partial sequencing of the 16S rRNA gene identified 60 % of the strains as belonging to genus Paenibacillus. The following four genera were also identified: Bacillus, Bradyrhizobium, Enterobacter and Pseudomonas. None of the strains fixed N2 free-living. Among the strains, 80 % solubilized Ca phosphate and one solubilized Al phosphate and none solubilized Fe phosphate. The highest IAA concentrations (52.37, 51.52 and 51.00 μg mL−1) were obtained in the 79 medium with tryptophan by Enterobacter strains UFPI B5-7A, UFPI B5-4 and UFPI B5-6, respectively. Only eight strains nodulated cowpea, however, all increased production of total dry matter. The fact that the strains evaluated perform different biological processes to promote plant growth indicates that these strains have potential use in agricultural crops to increase production and environmental sustainability

Estirpes de Bradyrhizobium em simbiose com guandu-anão em casa de vegetação e no campo

O objetivo deste trabalho foi avaliar a eficiência simbiótica de estirpes de bactérias fixadoras de nitrogênio do gênero Bradyrhizobium com guandu-anão. Os experimentos foram conduzidos em vasos de Leonard, em vasos com solo e em campo. Foram testadas 11 estirpes em vasos de Leonard, e as que apresentaram maior eficiência em promover o crescimento do guandu-anão foram avaliadas em vasos com solo (Latossolo Vermelho-Amarelo e Cambissolo) e em campo (Latossolo Vermelho-Amarelo). Em todos os experimentos, os tratamentos foram comparados a dois controles positivos (estirpes aprovadas como inoculantes para as cultivares de guandu-anão BR 2003 e BR 2801) e a duas testemunhas sem inoculação, uma com alta concentração de N mineral, e a outra, a depender do experimento, sem N mineral (solo) ou com baixa concentração de N (vasos de Leonard). Algumas estirpes proporcionaram crescimento vegetal semelhante ou superior às estirpes-referência e às testemunhas em vaso de Leonard. Em vasos com solo, o tipo de solo influenciou os tratamentos. No campo, não houve diferença entre os tratamentos, e as estirpes nativas promoveram bom crescimento. O guandu-anão é capaz de estabelecer associação simbiótica com bactérias fixadoras de N2, e a estirpe UFLA 03-320 apresenta potencial para ser recomendada para a cultura junto com a estirpe BR 2801

Cowpea symbiotic efficiency, pH and aluminum tolerance in nitrogen-fixing bacteria

Cowpea (Vigna unguiculata) cultivation in northern and northeastern Brazil provides an excellent source of nutrients and carbohydrates for the poor and underprivileged. Production surplus leads to its consumption in other regions of Brazil and also as an export commodity. Its capacity to establish relationships with atmospheric nitrogen-fixing bacteria is crucial to the reduction of production costs and the environmental impact of nitrogen fertilizers. This study assessed the symbiotic efficiency of new strains of symbiotic nitrogen-fixing bacteria with cowpea and their tolerance to pH and aluminum. Twenty-seven strains of bacteria from different soils were evaluated under axenic conditions. These strains were compared to the following inoculant strains: INPA03-11B, UFLA03-84 and BR3267 and two controls that were not inoculated (with and without mineral nitrogen). Six strains and the three strains approved as inoculants were selected to increase the dry weight production of the aerial part (DWAP) and were tested in pots with soil that had a high-density of nitrogen-fixing native rhizobia. In this experiment, three strains (UFLA03-164, UFLA03-153, and UFLA03-154) yielded higher DWAP values. These strains grow at pH levels of 5.0, 6.0, 6.8 and at high aluminum concentration levels, reaching 10(9) CFU mL-1. In particular UFLA03-84, UFLA03-153, and UFLA03-164 tolerate up to 20 mmol c dm-3 of Al+3. Inoculation with rhizobial strains, that had been carefully selected according to their ability to nodulate and fix N2, combined with their ability to compete in soils that are acidic and contain high levels of Al, is a cheaper and more sustainable alternative that can be made available to farmers than mineral fertilizers

Mycotoxins And Fungi In Wheat Harvested During 1990 In Test Plots In The State Of São Paulo, Brazil

Wheat from two cultivars with contrasting characteristics were harvested in ten experimental plots located in wheat producing areas of the State of São Paulo, Brazil. The samples (10 of each cultivar) were analyzed by a gaschromatographic method for deoxynivalenol (DON), nivalenol (NIV), diacetoxyscirpenol (DAS), toxins T-2 (T-2) and HT-2, T-2 tetraol, T-2 triol, and by a thin-layer chromatographic method for zearalenone (ZEN), aflatoxins B1, B2, G1, G2, ochratoxin A and sterigmatocystin. No mycotoxins were detected in 13 samples. DON was found in four samples (0.47-0.59 μg/g), NIV in three samples (0.16-0.40 μg/g), T-2 in two samples (0.40, 0.80 μg/g), DAS in one sample (0.60 μg/g), and ZEN in three samples (0.04-0.21 μg/g). The wheat samples were also examined for the incidence of fungi. Alternaria, Drechslera, Epicoccum and Cladosporium were the prevailing genera. Among the Fusarium spp., F. semitectum was present in 19 samples and F. moniliforme in 18 samples. No F. graminearum was isolated in the samples. © 1995 Kluwer Academic Publishers.131318519