Banca de DEFESA: BIANCA BOMFIM ANDRADE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : BIANCA BOMFIM ANDRADE
DATA : 25/02/2021
HORA: 10:00
LOCAL: pela plataforma digital Conferência Web
TÍTULO:

BIOMASS PRODUCTION AND CHARACTERIZATION OF MICROALGAE OBTAINED DURING CULTIVATION WITH RE-USED MEDIUM

PALAVRAS-CHAVES:

MICROALGAE, BIOPROCESS, RE-USED MEDIUM, ELECTROFLOCCULATION

PÁGINAS: 60
GRANDE ÁREA: Outra
ÁREA: Multidisciplinar
RESUMO:

Microalgae are microscopic, prokaryotic or eukaryotic, single-celled and photosynthetic organisms found in marine, freshwater and terrestrial environments. Its rapid growth, diversity of metabolites, ability to adapt to adverse conditions and composition with large amounts of proteins, carbohydrates, pigments, lipids and other biomolecules are responsible for its great biotechnological importance. One of the alternatives for reducing the cost of producing microalgae biomass is the reuse of the culture medium, which consists of the separation of microalgal biomass and the consequent inoculation of the residual medium, which can be supplemented or not with nutrients. Once cultivated, the biomass produced needs to be separated from the culture medium in order to be used in different industrial processes. It is estimated that the cost of separation can reach 20–30% of its total production cost. Electroflocculation is a method of separating biomass that is ecologically correct, inexpensive and energy efficient and consists of the use of two metallic electrodes (an anode and a cathode) that release ions that neutralize the charge of the microalgal cells and allows the formation of cell flakes, resulting in the separation of biomass. Thus, the development of technologies for the production and separation of microalgal biomass that allow cost reduction, without compromising the efficiency and quality of the process, is of great importance for the establishment of biomolecules obtained from microalgae on the world market. Therefore, this work aims to verify the effect of the reuse of medium during the cultivation of marine and freshwater algae, as well as the electrofloculation test as a method for separating the biomass from marine microalgae. For this, the microalgae Dunaliella salina and Ankistrodesmus falcatus were grown in an Erlenmeyer type photobioreactor (1 L) in Conway and LC-Oligo media, respectively. D. salina was submitted to 3 different culture conditions: standard medium, medium supplemented with nitrogen and medium supplemented with phosphorus. At the end of each cycle, the residual medium was reused, receiving a new inoculum of D. salina. The parameters of maximum production, maximum growth rate and maximum productivity were analyzed. There was a reduction in biomass production, maximum growth and productivity during cultivation in the non-supplemented medium and supplemented with phosphorus after 3 cycles. In the medium supplemented with Nitrogen there was a significant increase in the production of biomass in the media reused in comparison to the Control culture. The highest biomass production was obtained in the 1st cycle in a reused medium (1,122 g L-1 ). The 4th cultivation cycle promoted greater biomass production than the 3rd cycle (0.908 g L-1 and 0.854 g L-1 , respectively). The maximum productivity increased significantly during the cultivation cycles in reused medium, with the highest productivity obtained in the 4th cycle (0.201 g L-1 d -1 ). Cell death was observed during cultivation of A. falcatus in reused medium. In addition, an electroflocculation device for a tubular photobioreactor was developed, consisting of two parallel aluminum electrodes and an electrical source with voltage adjustment (12V–24V) for separating microalgae biomass, which resulted in the filing of a model patent used together to the National Institute of Industrial Property.

MEMBROS DA BANCA:
Externo(a) à Instituição - EDSON DE JESUS MARQUES - UNEB
Presidente - 1674313 - SUZANA TELLES DA CUNHA LIMA
Externo(a) à Instituição - TAIARA AGUIAR CAIRES