Ação in vitro de diferentes apresentações do ozônio na inativação do Pythium insidiosum equino

• Ano de defesa: 2020
• Autor(a) principal: Costa, Guilherme Barbosa da
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade de Franca; Brasil; Pós-Graduação; Programa de Mestrado em Ciência Animal; UNIFRAN
• Palavras-chave em Português: Equinos - Pitiose; Água; Cavalo; Gás; Óleo de girassol; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA
• Link de acesso: https://repositorio.cruzeirodosul.edu.br/handle/123456789/1164

The low effectiveness of current treatments makes pythiosis a chronic infection with a high recurrence in both humans and horses. However, ozone (O3) has been shown to be highly effective in inactivating various microorganisms. Thus, the present study aimed to characterize the in vitro antimicrobial effect of different O3 presentations against P. insidiosum cultures isolated from horses. In Experiment 1, fragments of P.insidiosum were treated with water enriched with O3, ozonized oils with different peroxide index or gas mixture O2-O3 (72 μgO3 mL-1). In Experiment 2, one or three treatments with O2-O3 gas mixture (72 μgO3 mL-1) were performed. In Experiment 3, the cultures were exposed to the O2-O3 gas mixture (72 μgO3 mL-1) for 05, 15 or 30 minutes. In Experiment 4, treatments were carried out with different concentrations of gas mixture O2-O3: 32, 52 or 72 μgO3 mL-1. The fragments were kept on Sabouraud dextrose agar (ASD) together with the vehicle used in each experiment and incubated for 14 days at 35 ° C. The growth zone was digitally measured during the first 14 days after treatment. Samples that did not grow over the first 14 days after treatment were cultured to assess the germicidal / germ mystatic action of the respective treatment. In Experiment 1, ozonized sunflower oil with a high peroxide index was the only presentation with germicidal action against the pathogen. The fragments submitted to the other treatments showed similar growth rates (P> 0.1) to the control groups. In Experiment 2, treatment for three consecutive days with an O2-O3 mixture was effective in inhibiting P. insidiosum. In Experiment 3, a negative effect of the exposure time on the growth rate of the cultures was detected (P <0.05). In Experiment 4, all treatments showed a germicidal effect regardless of O3 concentration. It is concluded that exposure to O3 gas, with multiple treatments, time between 15 to 30 minutes and concentrations between 32 to 72 μgO3 mL-1 and treatment with ozonized sunflower oil with a high peroxide index> 600 mEq kg-1 have an action germicidal against P.insidiosum isolated from equine. Keywords: gás; horse; pythiosis; sunflower oil; water.