To document the safety of pachybasin, a secondary metabolite of Trichoderma harzianum, for use as a bioagricultural agent, it was subjected to general toxicological testing in mice and developmental toxicity in zebrafish. With either 5 or 20 mg kg-1 pachybasin i.p. injection, mice behavioral responses such as motor coordination, spontaneous locomotor activity, or nociceptive pain were not influenced. In long-term effect (daily injection for 14 days), the physiological, hematological, liver, and kidney functions were not altered either. Evidence for the developmental toxicity of pachybasin (10-100 μM) in 72-h exposure period was shown in zebrafish larvae, based on developmental retardation, impairment of chorion, and increase of mortality. In summary, there are no significant general toxicities presented in the pachybasin-treated adult male mice. However, the embryo-toxicity in aquatic biota should be taken into consideration during bioagricultural agent application.
Keywords: Trichoderma harzianum; developmental toxicity; general toxicity; pachybasin.