Standardization of the bioencapsulation of enrofloxacin and oxytetracycline in Artemia franciscana Kellogg, 1906

Abstract

Bioencapsulation of enrofloxacin and oxytetracycline into Artemia franciscana nauplii was standardized. Both antibacterials were delivered to the nauplii individually and the amounts used in the study were percentages of the lipid emulsion Rich® added as nutrition enrichment for the nauplii. The determination of the amounts of drug incorporated in A. franciscana nauplii was obtained using a bioassay radial diffusion method, standardized in the laboratory and using Escherichia coli as an indicator. The minimum time for full enrichment for both enrofloxacin and oxytetracycline bioencapsulation in A. franciscana nauplii was 4 h after the initial exposure of the nauplii to the antibiotics and this was established sampling nauplii at 1, 2, 3, 4, 8 and 24 h after adding the nauplii to the mix. These experiments were carried out twice and at 4 h, 1.10 and 1.13 ng of enrofloxacin per nauplius and 9.32 and 9.37 ng of oxytetracycline per nauplius were obtained. The optimum percentages of enrichment were 40% of enrofloxacin in relation to Rich® and 80% of oxytetracycline. The percentages tested were 10%, 20%, 30%, 40% for the enrofloxacin and 0%, 40%, 80%, and 160% for the oxytetracycline. The maximum time at which antibiotic was still detected in the Artemia after it had been introduced in seawater was 8 h for both antibacterial agents.