Banca de QUALIFICAÇÃO: FERNANDO ABREU OLIVEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : FERNANDO ABREU OLIVEIRA
DATE: 25/07/2022
TIME: 16:00
LOCAL: Google meet_ SALA VIRTUAL
TITLE:

Analysis of microcystins in water from the Tapajós River using the High Performance Liquid Chromatography method and detection in PAD

KEY WORDS:

Cyanotoxins, cyanobacterial blooms, HPLC, Validation.

PAGES: 62
BIG AREA: Ciências Biológicas
AREA: Microbiologia
SUBÁREA: Biologia e Fisiologia dos Microorganismos
SUMMARY:

Microcystins (MCs) are hepatotoxic heptopeptides of cyanobacteria and are potent inhibitors of protein phosphatase in eukaryotic cells. The raw water samples from the Tapajós River were collected near the riverside communities between the cities of Santarém and Itaituba in the lower Amazon region. MC-RR, MC-YR and MC-LR microcystins were extracted and purified by Solid Phase Extraction (SPE) and analyzed by High Performance Liquid Chromatography (HPLC) with photodiode array detection (PAD). The analysis was validated according to the criteria of Resolution Nº 166 of the National Health Surveillance Agency (ANVISA). The method proved to be linear with a coefficient of determination greater than 0.9950 in the working range of 0.2 to 1.0 µg/mL. We obtain accuracy values between 80.01 and 107.69%, relative standard deviation values of repeatability precision between 1.429 and 9.535%, detection limit values between 0.104 and 0.174 µg/mL and quantification limit between 0.167 and 0.205 µg /mL for the three MCs. A total of 38 samples of raw water were collected and subdivided into 38 samples of filtrate (extracellular) and 38 samples of biomass (intracellular). Of the total, 10 samples of filtrate and 5 samples of biomass were positive for MC, corresponding to 26.31% and 10.53%, respectively. The most predominant was MC-LR with a maximum of 2,204 µg/L in the community of Santarenzinho, in the ebb of the Tapajós River in September-21. The results show the importance of monitoring these toxins in the Tapajós River, because only through this knowledge it is possible to understand the impact of microcystins on the different uses of water for the communities involved.

BANKING MEMBERS:
Interno - 1770373 - PAULO SERGIO TAUBE JUNIOR
Externo ao Programa - 1544196 - DIEGO MAIA ZACARDI