Banca de QUALIFICAÇÃO: THAYNÁ MOURA DOS SANTOS.

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : THAYNÁ MOURA DOS SANTOS.
DATE: 29/07/2022
TIME: 14:00
LOCAL: Online - Google Meet
TITLE:

PROSPECTION OF LACTIC BACTERIA ISOLATED FROM THE INTESTINE OF Colossoma macropomum FOR USE AS PROBIOTICS IN INCREASE IN FISH PRODUCTION

KEY WORDS:

Tambaqui, probiotic, aquaculture, immunity, resistance.

PAGES: 25
BIG AREA: Ciências Biológicas
AREA: Microbiologia
SUBÁREA: Microbiologia Aplicada
SPECIALTY: Microbiologia Industrial e de Fermentação
SUMMARY:

The intensification of aquaculture production systems often leads to an increase in the incidence and severity of infectious and parasitic diseases. Conventionally, the control of fish diseases has as main focus the use of chemical compounds and antibiotics, causing impacts on animal and public health. Probiotics are widely studied as an alternative to the use of these compounds and were defined by the World Health Organization as live microorganisms capable of causing beneficial effects to the health of the host. Thus, this project aims to investigate the feasibility and efficacy of supplementation with strains of lactic acid bacteria isolated from the intestinal microbiota of healthy tambaqui, on the pathophysiological and zootechnical responses of this same challenged species Aeromonas hydrophila. For that, 10 tambaquis were acquired from local fishermen, coming from the Amazon River, in Santarém-Pa. The animals were euthanized by deepening the anesthetic plane and the gastrointestinal tract was removed for seeding in a Petri dish, containing TSA and MRS media plus Aniline Blue dye. The culture occurred from the direct seeding of stomach and intestinal contents and the mix (Intestine + feces). A total of 115 bacterial strains were isolated, which underwent characterization analyzes to investigate the viability and probiotic potential in vitro. Initially, Catalase and Gram stain tests were performed, with 66 positive isolates for lactic acid bacteria. Subsequently, the hemolytic activity of positive bacilli with negative catalase was evaluated, in which 5 did not present hemolysis, which were selected for the other analyzes (I3, I10, F4, M13, M14). For probiotic characterization of the bacteria, the viability and growth of lactic acid bacteria were verified at different pH (2.0; 3.0; 4.0; 5.0; 6.0; 7.0; 8.0; 9.0) for 12 hours, as well as tests for bile resistance, antagonist activity, auto and coaggregation, biofilm formation, antibiogram, hydrophobicity and lyophilization. For molecular identification of the studied species, PCR was performed using three primers: Lac 1 and 2, for Lactobacillus sp., Bac and 16S for Bacillus sp. and their products were separated in gel electrophoresis. Subsequent to the in vitro analyses, the in vivo pathogenicity test was performed, in which 0.5 mL of the isolates were inoculated into the coelomic cavity in 30 juvenile tambaquis, divided into 6 groups. The results obtained in the tests have shown that the isolates, belonging to the Lactobacillus genus, have characteristics of potential probiotics. Prospecting their technological and functional potential is extremely important for sustainable aquaculture production.

BANKING MEMBERS:
Presidente - 2383549 - GUSTAVO DA SILVA CLAUDIANO
Interna - 1636625 - MICHELLE MIDORI SENA FUGIMURA
Externo à Instituição - PAULO FERNANDES MARCUSSO