Banca de DEFESA: THAÍS DE SOUZA SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : THAÍS DE SOUZA SANTOS
DATA : 22/09/2021
HORA: 09:00
LOCAL: Faculdade de Farmácia
TÍTULO:

Alternative biosynthesis of xanthan gum in petroleum industry wastewater and cassava waste: production and characterization

PALAVRAS-CHAVES:

Xanthan; viscosity; waste; Xanthomonas axonopodis pv manihotis.

PÁGINAS: 72
GRANDE ÁREA: Ciências Agrárias
ÁREA: Ciência e Tecnologia de Alimentos
SUBÁREA: Ciência de Alimentos
ESPECIALIDADE: Química, Física, Fisico-Química e Bioquímica dos Alim. e das Mat-Primas Alimentares
RESUMO:

Xanthan gum is a microbial exopolysaccharide that has wide industrial application due to desirable properties such as high viscosity, water solubility, emulsion stabilization and gel formation. In recent years, studies have sought to evaluate the production of xanthan gum from the use of different agro-industrial residues, in order to reduce costs and add value to the products. Thus, this work aimed to evaluate the production of xanthan gum in wastewater from the petrochemical industry supplemented with cassava processing waste, as well as to characterize the biopolymers obtained. Initially, the physicochemical and metal composition of wastewater from the petrochemical industry (produced water) and the proximate composition (moisture, protein, lipids, carbohydrates and ash) of the cassava processing waste were evaluated. The production was carried out in a shaker at 180 rpm, 30 °C, during 72-96h of fermentation, with 50 mL of produced water and cassava residue (2% m/v) being incorporated into the fermentation medium. The gums obtained were characterized for rheology (apparent viscosity), emulsification index, infrared spectroscopy (FTIR) and thermal stability (TGA/dTGA). The maximum production was obtained in 72 hours of fermentation (6.80 g L^-1), the results show that there was no significant difference between the evaluated times (p ≤ 0.05). The viscosities obtained for the gums were 11.07 and 10.11 mPa⋅s, (72 and 96h respectively) at 25°C and 25s^-1 and as the shear rate increased (1000s^-1), the values of viscosity reduced (2.44 and 2.30 mPa⋅s for 72 and 96h respectively), confirming its pseudoplastic characteristic. The emulsification index for the gums of both times was equal to or greater than 50%, being considered a good emulsifying agent. The FTIR results showed that the gums obtained at different times of fermentation showed a similar spectral behavior. The samples showed four thermal events characteristic of xanthan gum and good thermal stability when compared to commercial gum. Given this, the results show the possibility of producing xanathan gum, amid produced water and cassava residue.

MEMBROS DA BANCA:
Presidente - 4725209 - CAROLINA OLIVEIRA DE SOUZA
Externo à Instituição - DENILSON DE JESUS ASSIS - UNIFACS
Externa à Instituição - GLEICE VALERIA PACHECO GOMES - IFBA