Mushrooms to live or die: toxicity of some Basidiomycota using Artemia franciscana.

Consumption of wild mushrooms has increased in recent years; however, not all of them are edible and there is no precise information on those that may cause poisoning. Therefore, studies to obtain data about their toxicity are needed. For this purpose, we used the brine shrimp Artemia franciscana, a crustacean employed in toxicity tests and with wide application in the toxin detection, including mycotoxins. Mushrooms were collected in the state of Jalisco, Mexico, with which aqueous extracts were prepared. Dilutions of the stock solution of each extract were made to final concentrations of 50, 100, 250, 500, and 1000 µg/mL. Potassium dichromate (PD) was used as positive control and artificial seawater as negative control. The median lethal dose (LD50) of extracts on nauplii of A. franciscana was calculated. The aqueous extracts obtained from Amanita amerivirosa, A. muscaria, Chlorophyllum molybdites, and Leucopaxillus amarus showed a LD50 < 70 µg/mL, similar to PD (LD50 = 37 µg/mL). This is the first indication of the probable toxicity of Leucopaxillus amarus in humans. Cantharellus cibarius and Scleroderma texense caused the lower toxicity to the nauplii. The brine shrimp bioassay was effective in evaluating the toxicity of Basidiomycota. Scleroderma texense has been reported to be toxic, but it was not for this crustacean nauplii, and probably not to humans either, as recent literature has reported.

[Macroscopic fungi from Sierra de Quila, Jalisco, Mexico: diversity and fungal similarity]. / Hongos macroscópicos de la Sierra de Quila, Jalisco, México: diversidad y similitud fungística.

Diversity and similarity of macrofungi of Sierra de Quila, Jalisco, México were analized in three different kinds of vegetation. Fungal diversity in the area is high. The pine-oak and cloud forests, were more diverse in their community structure than the oak forest. Similarity among the three kinds of vegetation was low, there are few species share among them; pine-oak and cloud forests show higher affinity than oak forests. This pattern of similarity is a general condition for others regions with environmental conditions similar to Sierra de Quila.