Banca de DEFESA: TUANIA NATACHA LOPES SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : TUANIA NATACHA LOPES SILVA
DATE: 27/02/2023
TIME: 08:00
LOCAL: https://meet.google.com/pnb-mcer-ory
TITLE:

Method of lysis and inactivation of probiotic species, bioprocess of production and microcapsule development

KEY WORDS:

lactic acid bacteria, probiotics, lysis, inactivation, antimicrobial, encapsulation, bioprocess.

PAGES: 155
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUMMARY:

Disturbances in the skin microbiota are related to infections and inflammation that cause diseases such a acne and others. Alternatives for treatment are probiotic strains. Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. The application of lysed and inactivated in the cosmetic industry is a trend. As long as the beneficial effects are maintained, they have advantages such as transportation, shelf life, risk of translocation and consumer infection. The aim of this study was to evaluate the antimicrobial activity of cell-free, lysed and inactivated supernatant, viability, sublethal damage, influence of the culture medium on different methods, optimize biomass production and microencapsulation of lactic acid bacteria (LAB) isolates. Cell-free supernatants from the fifteen LAB strains did not inhibit the growth of Corynebacterium xerosys ATCC 373 and Pseudomonas aeruginosa ATCC 15442. The only methods capable of completely inactivating all strains were thermal methods. Viability and sublethal damage was dependent on the strain, culture medium and lysis or inactivation method. The lysis and inactivation methods did not maintain antimicrobial activity against Cutibacterium acnes ATCC 6919. The SEM of the strains in whey showed organic matter surrounding the cells. The technique of emulsification / internal gelation with 5% sodium alginate provided encapsulation of 61.94% without lyophilization and 37.83% with lyophilization, without gastrointestinal survival. Physical-chemical characteristics were analyzed by FTIR and optical microscope. The microcapsule lost anti-acne activity. DE4 strain optimization was carried out by enriching the whey, using the fractional factorial design (DFF) and a central composite rotational design (DCCR), outlined by the Minitab program18. The bioprocess achieved a high level of cell growth, reaching values greater than 10¹⁵ CFU mL-1. We conclude that LAB in its lysed or inactivated and encapsulated forms did not maintain promising anti-acne activity. The optimization of probiotic strain production makes it increasingly possible to scale up the bioprocess.

BANKING MEMBERS:
Presidente - 1675931 - PAULO AFONSO GRANJEIRO
Externo ao Programa - 1748672 - ENIO NAZARE DE OLIVEIRA JUNIOR
Externa à Instituição - MARIA ESPERANZA CORTES SEGURA
Externo à Instituição - FLAVIANO DOS SANTOS MARTINS
Externo à Instituição - KENNIO FERREIRA PAIM - UFTM