Acute toxicity of crude extracts of Aspergillus quadrilineatus isolated from acha (Digitaria exilis Stapf).

In a survey of fungi and mycotoxin conterminating acha (Digitaria exilis Stapf) in Plateau State of Nigeria, 96 fungal isolates were made. Screening of the fungi isolates for their mycotoxin-producing potentials showed that Aspergillus quadrilineatus (Thom and Raper) produced some of the most toxic mycotoxins. Two extracts of the Aspergillus quadrilineatus (the petroleum ether soluble extracts [PER] and the petroleum ether defatted crude extract [PEDCR]) were tested for acute toxicity in mice, chicks and cattle. The ip LD50 of PER in mice was 1148 mg/kg, and the oral LD50 of PEDCR was 566 mg/kg in mice and 556 mg/kg in chicks. The ip LD50 of PEDCR in mice was 21 mg/kg. The toxic signs of PER and PEDCR in mice and chicks included tachypnea, tachycardia, anorexia, somnolence, diarrhea, coma and death. The main postmortem findings were congestion of heart, liver, kidney and lungs and sloughing of the wall of stomach and hemorrhagic enteritis. The histopathologic findings in dead animals included edema and mild degeneration of the myocardium and necrosis of kidney tubular epithelial cells, hepatocytes and bronchioles. The only clinical observation in 1 calf orally dosed with a culture of Aspergillus quadrilineatus of maize was transient whole body tremors which occurred 1 h after dosing, tachycardia and profuse salivation. No significant histopathologic changes were found in the organs of the sacrificed calf.