Banca de DEFESA: TAINÃ CRISIA DE SOUZA FONSECA
Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.STUDENT : TAINÃ CRISIA DE SOUZA FONSECA
DATE: 28/07/2022
TIME: 14:00
LOCAL: google meet
TITLE:
Production and characterization of biosurfactants isolated from Issatchenkia orientalis
UCP 1603 and Enterobacter clocae UCP 1597 with potential application in agricultureKEY WORDS:
Renewable substrates; Surfactants; Bioconversion; Seed germinatio
PAGES: 120
BIG AREA: Outra
AREA: Multidisciplinar
SUBÁREA: Biotecnologia
SUMMARY:
Biosurfactants are surface-active compounds, produced microbially and using renewable substrates, reducing surface and interfacial tension, offering several advantages over synthetic surfactants, such as low toxicity and high biodegradability, and they remain active at extreme pH, temperature and salinity. In this sense, investigations were carried out with the yeast c Issatchenkia orientalis UCP 1603 in the bioconversion of renewable residues (post-frying soybean oil, cassava wastewater and corn) in the production of biosurfactant, applying a Full Factorial Design 23, 10% inoculum, incubated at temperature of 28°C, under orbital agitation of 150rpm, for 72h. The results showed that test 4 (3.5% cornstarch, 6.5% residual soybean oil and 3.5% cassava) showed the greatest reduction in surface tension (29.9mN/m). From the selected condition, studies were carried out with the cultivation of I. orientalis UCP 1603 in Fernbach flasks containing (2 L) of the production medium and 10% of inoculum, incubated at 28°C, 150 rpm for 72 h. The fermentation showed a yield of 4.0242 of biosurfactant recovered by precipitating the cell-free metabolic liquid with 70% ethanol (2:1 v/v). The isolated biosurfactant presented surface tension of 28.7 mN/mm), critical micellar concentration-CMC of 800 mg/L, polypeptide nature, anionic character, high stability under extreme conditions (pH 4-10, salinity 5-25% and temperature 5-100°C) and no toxicity to cabbage (Brassica oleracea) and lettuce (Lactuca sativa) seeds. Other studies carried out with the biosurfactant isolated from I. orientalis UCP 1603 at a concentration of 10mg/200mL demonstrated its effect in inducing the germination of jucá (Libidibia ferrea) seeds, a plant native to Brazil, well adapted to the semiarid region that presents difficulties in the process of germination. The biosurfactant induced dormancy breaking with the germination of jucá seeds in 10 days, influencing the increase of the root and hypocotyl, demonstrating high biotechnological potential for agriculture. These results constitute a copyright reservation. Furthermore, the submerged fermentation with the bacterium Enterobacter clocae UCP 1597 using the alternative substrate post-frying soybean oil in saline, reduced the surface tension to 30.5 mN/m, interfacial 2.3 mN/m, biosurfactant yield extracted with ethyl acetate was 1.3g/L and CMC of the metabolic liquid was 70%. The biosurfactant showed no toxicity to cabbage seeds (Brassica oleracea). The stability in the range of pH 4-10 and extreme values of temperature and salinity, demonstrated an ionic, halotolerant and thermostable character. The investigations carried out showed the high biotechnological potential of Issatchenkia orientalis UCP 1603 and Enterobacter clocae UCP 1597, respectively, with promising and innovative results that contribute to the future of agrobiotechnology, in addition to demonstrating the need to use the circular bioeconomy in the conversion of agro-industrial waste .
BANKING MEMBERS:
Presidente - 002.501.554-00 - GALBA MARIA CAMPOS TAKAKI - UPE
Interna - 384972 - ANA LUCIA FIGUEIREDO PORTO
Externo ao Programa - 1646614 - MARCOS ANTONIO BARBOSA DE LIMA
Externa à Instituição - JULIANA MOURA DE LUNA - UNICAP
Externa à Instituição - ROSILEIDE FONTENELE DA SILVA ANDRADE