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Sixteen corn samples, 10 of national white corn and 6 of “criollo” white were analyzed to determine the Fusaria species present on the kernels, especially those reported as ear and kernel rot inducers, mainly those mycotoxin producers. The identifi ed species, ordered in relation to the number of obtained isolates were F. oxysporum, F. subglutinans, F. moniliforme, F. graminearum, F. anthophilum, F. poae, F. tricinctum, F. sporotrichioides, and F. proliferatum. The species F. oxysporum, F. tricinctum, and F. anthophilum have not been reported causing ear or kernel rots. All of the others have been reported as ear and kernel rots inducers, as well as stalk rots. Besides, most of these species produce various mycotoxins, many of which are capable of causing health problems to humans and animals.

Once muestras de diferentes nombres comerciales de mazapán fueron analizados para establecer sus perfiles de mohos así como determinar la presencia de aflatoxinas. En ninguna de las muestras analizadas fueron determinadas aflatoxinas Las especies de mohos identificadas correspondieron a los géneros Aspergillus, Fusarium, Penicillium, Rhizopus y Absidia.

Se analizaron 133 muestras representativas del maíz almacenado y distribuido en el estado de Sonora en 1998 para determinar presencia de aflatoxinas. Todas las muestras fueron de maíz blanco nacional, obtenidas de diferentes almacenamientos o transportes. La mayor parte de las muestras pertenecían a la cosecha 97/98, pero hubo algunas de las cosechas 96/97 y 98/ 98. En una tercera parte de las muestras se determinaron aflatoxinas; sin embargo, los niveles de contaminación estuvieron muy por abajo de los aceptados para la comercialización del grano.

Bioactivity-directed fractionation of extracts from the fungus Phoma herbarum led to the isolation of two new phytotoxic nonenolides: (7S,8S,9R)-7,8-dihydroxy-9-propyl-5-nonen-9-olide (1) and (2R,7S,8S,9R)-2,7,8-trihydroxy-9-propyl-5-nonen-9-olide (2), which were named herbarumins I and II, respectively. The stereostructures were elucidated by spectroscopic methods and a combination of molecular modeling, NOESY and 1H–1H coupling constant data, which revealed that in CDCl3 solution, 1 exists in one preferred conformation, while 2 exhibits a conformational equilibrium. Compounds 1 and 2 caused significant inhibition of radicle growth of seedlings of Amaranthus hypochondriacus.