A mycotoxicological survey on soil-borne Emericella collected from 369 soil samples from 10 areas in Brazil, Colombia, Paraguay and Venezuela, was carried out. Emericella spp. were isolated by using soil-plate method on Czapek's agar, incubating the plates at 37°C for 14 days. A higher occurrence of Emericella spp. was generally demonstrated in the soil samples of grassland and wasteland, which were collected from Botucatu in Brazil, Cartagena in Colombia, and Coro and Merida in Venezuela. The Emericella isolates were identified with E. acristata, E. dentata, E. echinulata, E. nidulans var. lata, E. nidulans var. nidulans, E. quadrilineata and E. rugulosa. For the 61 isolates assigned to 6 species and one variety of Emericella, the ability to produce sterigmatocystin (STG) and its related metabolites, such as norsolorinic acid and versicolorins, was examined on rice cultures at 25°C for 21 days. Moldy rice was extracted with ethyl acetate, and STG and its related metabolites in the extracts were confirmed by thin-layer chromatography. As the results, the following STG producers were found: E. acristata, E. dentata, E. echinulata, E. nidulans var. lata, E. nidulans var. nidulans, E. quadrilineata and E. rugulosa. The production of norsolorinic acid and versicolorin B and/or C was confirmed on the following species: E. acristata, E. dentata, E. nidulans var. lata, E. nidulans var. nidulans, E. quadrilineata and E. rugulosa. The norsolorinic acid production of Emericella spp. has been demonstrated for the first time.
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