In Vitro Effects of tyrosinase on the Egg and Adult Worm of .

Background: Several species of streptomycetes, saprophytic bacteria found widely distributed in soil, water and plants, produce bioactive compounds such as intra and extracellular hydrolases including lytic enzymes which reflecting on their importance in the biological control of insects and parasites. This study assessed the in vitro effects of tyrosinase, produced from spp. isolated from Egyptian soil, on animal-parasitic nematode , in terms of egg development and adult worm's cuticular structure, and as an alternative strategy to alleviate this infection.

Methods: This study was conducted at the National Research Centre, Egypt in 2018. Five different concentrations of tyrosinase, ranged from 1%-30% were tested against the development of eggs. The concentration induced the highest inhibitory activity was tested against adult cuticle, which is essential for the protective and nutritive functions. The results were compared with those observed in the egg development and worm cuticle following incubation in protease (as a reference enzyme).

Results: Compared to protease, higher inhibitory activity on egg development and extreme cuticular alterations of the treated adult worms had been observed following 24 h exposure to tyrosinase. Once the cuticle had been damaged, the enzyme would be able to penetrate deeper into the internal tissues of the nematode and caused more widespread disruption.

Conclusion: The current study could offer a promising bio-control agent, tyrosinase, against alternative to the more expensive synthetic anthelmintics.