Banca de QUALIFICAÇÃO: ISABELA NATÁLIA DA SILVA FERREIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : ISABELA NATÁLIA DA SILVA FERREIRA
DATE: 27/07/2022
TIME: 09:00
LOCAL: google meet
TITLE:

BIOSURFACTANT PRODUCTION BY Stenotrophomonas maltophilia UCP 1601 USING RENEWABLE SUBSTRATES AS A

PROMISING STRATEGY FOR APPLICATION IN THE RECOVERY OF SOIL CONTAMINATED BY PESTICIDES.

KEY WORDS:

Agriculture. Circular bioeconomy. Agro-industrial waste. Environmental recovery. Tensoactive.

PAGES: 120
BIG AREA: Outra
AREA: Multidisciplinar
SUBÁREA: Biotecnologia
SUMMARY:

The growing population generated a very high agricultural demand for inputs that, naturally, did not keep up with the food demand, mainly due to pests and weeds. Thus, chemical fertilizers have been used inordinately, causing damage to crop, considering that due to the excess 30 to 50% of these substances are applied to the soil, causing destruction of the soil structure, polluting groundwater, and food. These products are known as pesticides, or agrochemicals and are highly toxic. Biosurfactants are biomolecules of high technological interest, whose main feature is the reduction of surface tension, which consists of the force of attraction existing in molecules on the surface of liquids. This biomolecule has an amphipathic characteristic, that is, it has a polar (hydrophilic) and apolar (hydrophobic) character, which allows the solubilization of fluids with different degrees of polarity (water/oil). These abilities guarantee the application of biosurfactants as biodegradation agents and environmental recovery, due to the damage caused by pesticides. In this context, studies are being carried out aiming at an environmentally and economically sustainable alternative, through a biosurfactant produced by Stenotrophomonas maltophilia UCP 1601, with the objective of recovering soils impacted using pesticides. The biomolecule was produced in submerged fermentation, using different renewable substrates such as carbon and nitrogen sources, in addition to the use of two statistical tools, the Plakket-Burman experimental design and complete 24 factorial design, aiming to optimize the production of the biosurfactant. A partial characterization was performed through surface tension, emulsification index, determination of CMC, ionic charge and FITR (Fourier transform infrared spectroscopy). In addition, the biosurfactant was tested under different conditions of temperature, pH and salinity, in order to assess the stability of the biomolecule. The results obtained were very promising. The surface tension of the biosurfactant produced with corn steep liquor and glycerol was 27 mN/m, yield 12.6 g/L, and anionic character. The critical micellar concentration-CMC was 70% using the cell-free metabolic fluid. The biosurfactant was able to emulsify 56% of the burned engine oil. The biomolecule showed excellent thermal, ionic and saline stability. The results obtained were very promising. The surface tension of the
biosurfactant produced with corn steep liquor and glycerol was 27 mN/m, yield 12.6 g/L, and anionic character. The critical micellar concentration-CMC was 70% using the cell-free metabolic fluid. The biosurfactant was able to emulsify 56% of the burned engine oil. The biomolecule showed excellent thermal, ionic and saline stability. All determinations carried out confirm the generation of a new stable and efficient bioproduct under extreme conditions, corroborating the use of the circular bioeconomy in the reuse of agro-industrial residues. The programmed steps in the continuity of the research consist of evaluating the toxicity and phytotoxicity of the biosurfactant produced; to evaluate the potential for the biodegradation of the soil and food contaminant glyphosate pesticide; to evaluate the potential of the biosurfactant in the phytoprotection of agriculture; to evaluate the inducing action on seed germination by the biosurfactant produced, as well as to study other applicability related to the high potential of the biosurfactant, in the generation of copyright reservation.

BANKING MEMBERS:
Interna - 2066204 - RAQUEL PEDROSA BEZERRA
Externo ao Programa - 1646614 - MARCOS ANTONIO BARBOSA DE LIMA
Externa à Instituição - JUANIZE MATIAS DA SILVA BATISTA