Banca de DEFESA: ANA TERRA DE MEDEIROS FELIPE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ANA TERRA DE MEDEIROS FELIPE
DATE: 27/02/2025
TIME: 10:00
LOCAL: online meet.google.com/fgz-rbiy-dtt
TITLE:

Green macroalgae as sustainable resources: identification, characterization, exploration of bioactive potential and the development of cellulosic materials from Ulva sp. and Chaetomorpha sp. collected in Tibau do Sul, Northeast Brazil

KEY WORDS:

 Green algaes, antioxidant activity, antibacterial activity, cellulosic packaging, biodegradable. 

PAGES: 91
BIG AREA: Engenharias
AREA: Engenharia Química
SUBÁREA: Tecnologia Química
SPECIALTY: Alimentos
SUMMARY:

The growing demand for sustainable resources and the need to reduce environmental impact drive the search for new sources of renewable and versatile raw materials. In this context, marine macroalgae emerge as promising alternatives, offering applications ranging from the production of functional foods to the manufacture of packaging and biodegradable materials. This study investigated the biotechnological potential of the green macroalgae Ulva sp. and Chaetomorpha sp., collected in aquaculture ponds in the municipality of Tibau do Sul, Northeast Brazil, with emphasis on their physical-chemical, morphological characterization, bioactive, antioxidant, antibacterial properties and the use of fresh algae pulp as cellulosic materials. Physicochemical and phytochemical analysis revealed a profile rich in fibers, minerals and bioactive compounds, such as pigments, phenolic compounds and fatty acids, in the algal extracts. Methanolic extracts demonstrated greater efficiency in the extraction of bioactives and superior antioxidant activity compared to aqueous and ethanolic extracts, through a combined extraction between the ultrasound method followed by a solid-liquid extraction. The methanolic extracts of Ulva sp. presented total phenolic contents greater than 7 mg GAE/100 g of oven-dried powder, while the extraction of pigments, total chlorophylls and carotenoids, presented 73 mg/g and 17.75mg/g, respectively. The analysis of fatty acids in Ulva sp. detected essential compounds, such as palmitic acid and linoleic acid, highlighting the functional potential of these macroalgae. Antioxidant activity tests demonstrated the ability to capture free radicals using the DPPH and ABTS methods, with inhibition values of 20% in methanolic extracts, while assessments of the minimum inhibitory concentration indicated the effectiveness of methanolic and ethanolic extracts against Gram-positive and Gram-negative bacterias. Furthermore, among the polysaccharides extracted from both species studied, cellulose extracted from Chaetomorpha sp. presented an average yield of approximately 20%, twice as high as that extracted from Ulva sp., demonstrating the ability to form cellulosic material from Chaetomorpha sp. These cellulosic sheets exhibited promising characteristics, presenting an average thickness of 0.680 mm and a surface structure with the presence of long, well-organized fibers, reinforcing the potential of this biomass as a cellulosic material. The results of this study highlight the value of green macroalgae as a sustainable and environmentally responsible resource, and also highlights its relevance for the advancement of the blue bioeconomy, promoting the appreciation of local marine biodiversity and contributing to the development of more sustainable solutions in various industries, including food. , packaging, cosmetics and pharmaceuticals.

COMMITTEE MEMBERS:
Presidente - 1517220 - MARCIA REGINA DA SILVA PEDRINI
Interna - 1246737 - ROBERTA TARGINO HOSKIN
Externa à Instituição - EDILENE SOUZA DA SILVA - USP