Banca de DEFESA: MARILIA ALMEIDA DOS SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MARILIA ALMEIDA DOS SANTOS
DATE: 27/07/2026
TIME: 09:00
LOCAL: Sala de aula do PPGCAP, Prédio A, UFAPE.
TITLE:

Production and biochemical characterization of phytase from *Mucor lusitanicus* URM 7853 and its potential applicability in diets for aquatic organisms

KEY WORDS:

Aquaculture; Enzymatic bioavailability; Phosphorus; Solid-State Fermentation.

PAGES: 100
BIG AREA: Ciências Agrárias
AREA: Zootecnia
SUBÁREA: Nutrição e Alimentação Animal
SPECIALTY: Avaliação de Alimentos para Animais
SUMMARY:

The increasing use of plant-based ingredients in aquaculture feeds highlights the importance of
phytases due to their ability to hydrolyze phytate, thereby increasing phosphorus
bioavailability, reducing the need for inorganic phosphorus supplementation, and minimizing
environmental impacts. This dissertation was structured into two studies: a scientometric survey
on the use of phytases in diets for fish and shrimp, and the production and biochemical
characterization of a fungal phytase obtained from Mucor isolates. In the first study, a
scientometric analysis of the literature indexed in the Web of Science database was conducted
using the descriptors phytase AND fish and phytase AND shrimp, covering the period from 2014
to 2024. A total of 187 documents were analyzed using bibliometric techniques with the aid of
the VOSviewer and Bibliometrix software packages. The results demonstrated the growth of
scientific production on the use of phytases in aquaculture, highlighting Pakistan as the leading
contributor to research in the field and the journals Aquaculture and Aquaculture Nutrition as
the main publication outlets. Furthermore, the principal scientific collaboration networks,
keywords, and research trends were identified, revealing the limited representation of studies
focused on shrimp farming. In the second study, a phytase produced by Mucor lusitanicus URM
7853 was produced and biochemically characterized through solid-state fermentation using
wheat bran as the substrate. Enzyme production was optimized using a full 23 factorial design,
evaluating the effects of glucose concentration, moisture content, and substrate mass.
Subsequently, the optimum pH and temperature, thermal stability, kinetic parameters, and the
influence of metal ions on enzyme activity were determined. The phytase exhibited optimum
activity at pH 5.0 and 40 °C. Thermal stability was evaluated between 50 and 80 °C, with the
longest half-life observed at 50 °C (990.21 minutes), indicating potential application during
feed-drying processes under controlled temperatures. The kinetic parameters were Km of 24.16
mM and Vmax of 83.33 mM/min, and enzyme activity was enhanced in the presence of Ca2+ and
Fe2+ ions. It is concluded that the scientometric survey demonstrates the expansion of scientific
interest in the use of phytases in aquaculture and highlights the need for further studies,
particularly in shrimp farming. Furthermore, the phytase produced by M. lusitanicus URM 7853
exhibited promising biochemical characteristics, indicating potential for future applications in
the nutrition of aquatic organisms and contributing to the development of more sustainable
strategies for aquaculture.

 

COMMITTEE MEMBERS:
Presidente - ***.665.454-** - RODRIGO LIRA DE OLIVEIRA - UFAPE
Externo ao Programa - ***.960.754-** - JOSÉ ERICK GALINDO GOMES - UFRPE
Externa à Instituição - TATIANA SOUZA PORTO - UFRPE