Effect of marine extracts on the microbial pathogens causing flacherie in the mulberry silkworm, Bombyx mori L

ABSTRACT

Objective: Silkworms are invertebrate animals that are killed by bacteria pathogenic against humans, such as Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa and Vibrio cholera. Biochemical characterization of the microbes in the haemolymph of diseased silkworm collected during the survey indicated the presence of Bacillus sp., Streptococcus sp., Staphylococcus sp. and Pseudomonas sp. in the culture. Methods: Studies were carried out in vitro to assess the efficacy of some marine extracts for the containment of these microbes through turbidimetry analysis and zone of inhibition test. Results: The observations made during this study revealed that the ethyl acetate crude extracts of two marine samples are Auroraglobostellata and Spirostella inconstans var. moendrina Dendy effective against these microbes causing flacherie diseases in silkworm. The comparison of their effects indicated that ethyl acetate extracts were generally more effective Extensive studies using these extracts on the growth and cocoon production of the mulberry silkworm, Bombyx mori L. are likely to throw much light on the possibility of using such extracts as a prophylactic measure during silkworm rearing to improve silk production. Conclusions: Also, the results indicate that maybe plays a possible role in the contamination of humans and animals, in particular silkworms, while marine extracts showed a potential to control the contamination caused by bacterial diseases.