66ª Reunião Anual da SBPC

Resumo aceito para apresentação na 66ª Reunião Anual da SBPC pela(o): SBPC - SOCIEDADE BRASILEIRA PARA O PROGRESSO DA CIÊNCIA

C. Ciências Biológicas - 3. Bioquímica - 1. Bioquímica

MICROBICIDAL ACTIVITY OF TOAD CRUDE VENOM FROM Rhinella marina (ANURA: BUFONIDAE)

Tiago Bispo Rego - Centro de Estudos de Biomoléculas Aplicadas a Saúde-CEBio/Fiocruz/RO-UNIR. Cleópatra Alves da Silva Caldeira - Centro de Estudos de Biomoléculas Aplicadas a Saúde-CEBio/Fiocruz/RO-UNIR. Diana da Silva Butzke - Centro de Estudos de Biomoléculas Aplicadas a Saúde-CEBio/Fiocruz/RO-UNIR. Najla Benevides Matos - Centro de Pesquisa em Medicina Tropical de Rondônia-CEPEM, Porto Velho-RO. Leonardo de Azevedo Calderon - Orientador–CEBio/Fiocruz/RO-UNIR.

INTRODUÇÃO:

The skin of amphibians is a complex organ with morphological, biochemical and physiological characteristics that is involved in various important processes for the survival of these animals, such as respiration, excretion, water regulation, climate control, reproduction, camouflage, antimicrobial activity and antifungal functions. Anura bufonidae present one pair of agglomerated glands at the post-orbital region on either side of the body, named paratoid macroglands. This structure is responsible for the secretion, production and storage of venom, which contains steroids, biogenic amines, proteins and peptides. It is known that these compounds, which protect frogs’ skin against bacterial, fungal and protozoan growth and participate in an efficient defense system against attack by predators, are considered the largest natural deposit of bioactive compounds in the animal kingdom.

OBJETIVO DO TRABALHO:

The objective was to verify the microbicidal activity of Rhinella marina crude venom.

MÉTODOS:

The bactericidal activity was defined as the Minimum Inhibitory Concentration (MIC). The MIC was determined by microdilution susceptibility testing Staphylococcus aureus (ATCC 29213) were grown in Luria Bertani broth (LB) for 24 hours with an absorbance turbidity equivalent to 1.5x106 colony forming units (CFU)/mL. The crude venom of Rhinella marina was added to the bacterial suspension (1.5x106 CFU/mL) of the strains at concentrations of 10, 25, 50 and 100 mg/µL in 96 well microplates for 24 hours at 37°C. For the negative control, we used the LB broth, the positive control was performed with the bacterial suspension in LB broth, and the control Chloramphenicol was added to bacteria in a culture medium. Inhibition of bacterial growth was determined by spectrophotometry at a wavelength of 630 nm, and then the obtained values were calculated with the software Prisma 5.0 (one-way ANOVA, p <0.05).

RESULTADOS E DISCUSSÃO:

The crude venom was tested and showed significant activity, exceeding 60% inhibition of Staphylococcus aureus proliferation. The concentrations tested (10, 25, 50 and 100 mg/µL), demonstrated 73.18%, 69.58%, 66.85%, 66.85% and 65.56% inhibition, respectively, so the venom has inhibitory activity in both strains.

CONCLUSÕES:

In this study it was concluded that Rhinella marina venom presents microbicidal activity.

Palavras-chave: Rhinella marina, Staphylococcus aureus, Microbicidal Activity.