Article
Biochemistry & Molecular Biology
Bjarte Aarmo Lund, Bjorn Olav Brandsdal
Summary: A new method was developed to efficiently determine the temperature dependence of enzyme catalysis, requiring less sample, labor, and time. The method was validated with Bacillus pumilus LipA enzyme and three different enzymes, effectively differentiating between enzyme types at various temperatures.
Article
Chemistry, Analytical
A. Eswari, S. Saravanakumar
Summary: The study discusses a mathematical model of an immobilized enzyme system in a micro-disk biosensor, based on Michaelis-Menten kinetics. The analytical expressions for substrate and hydrogen peroxide concentrations and electrode current were obtained using a hyperbolic function method. The proposed model's efficiency was confirmed through comparison with established methods and numerical results provided by MATLAB.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2021)
Article
Biology
Sylwester M. Kloska, Krzysztof Palczynski, Tomasz Marciniak, Tomasz Talaska, Marissa Miller, Beata J. Wysocki, Paul Davis, Tadeusz A. Wysocki
Summary: This paper presents a fi-oxidation model of fatty acids based on queueing theory, which uses Michaelis-Menten enzyme kinetics and literature data to optimize the parameters for the pathway reactions. The model enables real-time tracking of changes in the concentrations of metabolites with different carbon chain lengths, and can also predict the changes caused by system disturbance. It has been validated against experimental data and can be used to understand diseases that change fatty acid metabolism and determine the initial target of treatment.
COMPUTATIONAL BIOLOGY AND CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Yu Zhang, Ying Zhang, Miaojia Song, Evangelos Topakas, Qiang Yu, Zhenhong Yuan, Zhongming Wang, Ying Guo
Summary: Conversion of lignocellulose to sugar relies on costly cellulase and xylanase, therefore, improving enzyme utilization is crucial. Enzymatic kinetics can guide researchers to efficient enzyme utilization, with models based on second-order reactions being superior to first-order ones. Enzyme activity and sugar yield have a linear relationship, while higher enzyme loading leads to reduced activity retention.
PROCESS BIOCHEMISTRY
(2021)
Article
Food Science & Technology
Juan Blanco, Helena Martin, Carmen Marino, Araceli E. Rossignoli
Summary: The study investigated the depuration kinetics of okadaic acid in cockles and found that cockles depurated the toxin faster than most other bivalve species. Two-compartment models were needed to describe the depuration process effectively, and esters were depurated at a faster rate than the free form of the toxin.
Article
Chemistry, Physical
Ashutosh Kumar, R. Adhikari, Arti Dua
Summary: The hyperbolic dependence of catalytic rate on substrate concentration, as described by the Michaelis-Menten equation, has been rationalized through graph-theoretic analysis in various chemical and biological contexts. However, experiments have shown that molecular noise can lead to deviations from classical results and unexpected effects such as molecular memory. The study proposes new statistical measures to differentiate between transient and steady-states, providing insight into the non-classical regimes of catalysis at the molecular level.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Rumasha N. T. Kankanamage, Ben K. Ahiadu, Jie He, James F. Rusling
Summary: Enzymes serve as effective catalysts in organic syntheses, offering high selectivity that is often not achievable with chemical catalysts. Biocatalysis with iron heme enzymes in thin films has demonstrated improved stability and efficiency. Utilizing polylysine-crosslinked horseradish peroxidase (HRP) coatings on magnetic beads, selective synthesis of single nitro-phenol products was achieved for a series of para-substituted phenols. This approach shows promise as a valuable tool for biocatalytic chemical synthesis, with significantly improved turnover numbers at elevated temperatures.
Article
Multidisciplinary Sciences
Maryam Khan, Zubair Ahmad, Farhad Ali, Naveed Khan, Ilyas Khan, Kottakkaran Sooppy Nisar
Summary: This research focuses on the modelling and dynamics of enzyme processes based on chemical kinetics. A two-step reversible reaction of substrate-enzyme is investigated and transformed into a fractional-order model using the Atangana-Baleanu operator and Mittag-Leffler kernel. The numerical results obtained through the Atangana-Toufik method show the dynamics of the reaction against different reaction rates.
Article
Engineering, Chemical
Blaine F. Severin, Thomas D. Hayes
Summary: Volt-Amp profiles are used to describe electrodialysis dynamics. The Michaelis-Menten function is suitable for saturated chemical reactions in the process. Experimental results show that reactions in the electrodialysis process are interdependent.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Biology
Dimitrios Ritis, Georgios C. Boulougouris
Summary: In recent decades, understanding of the biochemical processes supporting various biological systems has increased significantly, leading to reverse engineering of certain complex life processes. One prominent example is the design of modern computers to mimic neuron activity, as part of efforts to bring advances in computation and electronics back to biology. By presenting a set of requirements for designing biochemical analogs of modern electronics and implementing it through numerical simulations and a Python library, the study aims to bridge the gap between combinatorial and sequential logic in the modern theory of automata.
COMPUTERS IN BIOLOGY AND MEDICINE
(2021)
Article
Microbiology
Karim Fahmy
Summary: Quantitative analysis of cell replication explores the relationship between metabolism and growth by proposing a growth model with enthalpy as a variable. Isothermal microcalorimetry traces show consistent patterns in the enthalpy domain, which align with a Langmuir adsorption reaction model. The proposed formalism accurately captures the lifespan of cultured microorganisms from exponential growth to metabolic decline.
Article
Chemistry, Analytical
Shengmei Tai, Zhijuan Qian, Hongxin Ren, Alberta Osei Barimah, Chifang Peng, Xinlin Wei
Summary: A colorimetric detection method for Glyp was developed using beta-CD@DNA-CuNCs enzyme mimics, showing high sensitivity and selectivity. The method established by detecting the changes of absorption signal at 652 nm provides a potential approach for monitoring Glyp residue in food.
ANALYTICA CHIMICA ACTA
(2022)
Article
Biochemistry & Molecular Biology
Florian Labourel, Etienne Rajon
Summary: Enzyme efficiency is influenced by competition for resources and undergoes directional selection up to a certain point before evolving near-neutrality. Evolutionary outcomes for enzymes vary due to differences in the evolutionary context encountered by each enzyme, with drift and effective population size playing important roles. Joint evolution of enzyme concentration and efficiency does not lead to extensive variance in outcomes, suggesting that other factors such as the kinetics of nutrient transporters, tolerance to high concentrations of metabolites, and reversibility of reactions are also significant.
MOLECULAR BIOLOGY AND EVOLUTION
(2021)
Article
Chemistry, Multidisciplinary
Chathuri J. Kombala, Sanjaya D. Lokugama, Aikaterini Kotrotsou, Tianzhe Li, Alyssa C. Pollard, Mark D. Pagel
Summary: A newly developed CEST agent can simultaneously measure pH and evaluate protease activity, with the ability to determine pH values through selective saturation signals and ratio analysis.
Article
Nanoscience & Nanotechnology
Rong Liu, Dajiao Cheng, Quan Zhou, Fushuang Niu, Ke Hu
Summary: Synthetic nanomaterials known as nanozymes can catalyze biological transformations, and photonanozymes utilize light for spatial and temporal control. A gold nanocluster modified with glutathione serves as a photonanozyme, catalyzing the reduction of nitrobenzene under light and showing potential as a biocompatible catalyst in mammalian cells. This study reinvents gold nanoclusters as photonanozymes, mimicking natural nitroreductases for potential prodrug activation.
ACS APPLIED NANO MATERIALS
(2021)
Article
Entomology
Ananias Pascoal, Emerson Dechechi Chambo, Leticia M. Estevinho
Summary: This study evaluated the botanical origin and physicochemical parameters of bee pollen samples harvested in different regions of northeast Portugal, and studied their antioxidant potential. The results showed differences in botanical origin and physicochemical parameters between samples from different locations.
JOURNAL OF APICULTURAL RESEARCH
(2023)
Article
Biochemistry & Molecular Biology
Antonia Goncalves, Fernando Rocha, Berta N. Estevinho
Summary: This study proposed the co-encapsulation of retinoic acid (RA), curcumin, and/or resveratrol into microparticles made of alginic acid sodium and a blend of ethyl cellulose + polyethylene glycol (EC + PEG) for protection and co-delivery of these bioactive compounds. The aim was to harness the combined therapeutic potential of these molecules for the treatment of acute promyelocytic leukemia (APL) using spray-dried microparticles. The encapsulation efficiency and release profile of the co-encapsulated bioactive compounds were influenced by the encapsulating agents used in the micro-particles formulations.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2023)
Article
Polymer Science
Silvia Castro Coelho, Fernando Rocha, Berta Nogueiro Estevinho
Summary: In this study, two approaches were developed to encapsulate vitamin B9 and microstructures were fabricated to improve stability and antioxidant capacity. The results showed that specific encapsulation structures can be used to enhance the antioxidant activity of vitamin B9 in food and nutraceutical fields.
Article
Food Science & Technology
Antonia Goncalves, Fernando Rocha, Berta N. Estevinho
Summary: Microparticles based on ethyl cellulose were prepared using the spray-drying process for the encapsulation of retinoic acid. The results showed that these microparticles had a suitable controlled delivery system and exhibited good encapsulation efficiency and release rate.
Review
Chemistry, Medicinal
Antonia Goncalves, Fernando Rocha, Berta N. Estevinho
Summary: Acute promyelocytic leukemia (APL) is a type of leukemia characterized by genetic abnormalities and the accumulation of abnormal promyelocytes. All-trans retinoic acid (all-trans RA) has dramatically improved the treatment of APL by promoting the differentiation of leukemic cells. Encapsulation technology using microparticle formulations obtained by spray-drying is being explored as an innovative strategy to improve the oral administration of all-trans RA. The goal is to develop a controlled delivery system that can provide a slow release of the drug in the intestines.
Review
Biochemistry & Molecular Biology
Silvia Castro Coelho, Berta Nogueiro Estevinho
Summary: Plant extracts, particularly polyphenols, are important sources of antioxidants. However, their application is limited by factors such as environmental instability, poor bioavailability, and activity loss. Electrohydrodynamic processes offer a promising solution by creating microstructures that can encapsulate active compounds and control their release. These electrospun/electrosprayed structures have advantages like high surface-area-to-volume ratio, porosity, excellent materials handling, and scalable production, making them suitable for various fields, including the food industry. This review provides an overview of electrohydrodynamic processes, key studies, and their applications.
Article
Biochemistry & Molecular Biology
Ana F. Couto, Maena Favretto, Raphael Paquis, Berta N. Estevinho
Summary: EGCG and vitamin B12, known for their antioxidant and anti-inflammatory characteristics, are prone to degradation during industrial processes. This study aims to microencapsulate EGCG and vitamin B12 using an electrospinning technique to protect them from external factors. The results showed that high encapsulation efficiencies were achieved, especially with 1% w/w of active substance and 30% w/v of zein.
Article
Thermodynamics
Pedro Velho, Berta N. Estevinho, Eugeinia A. Macedo
Summary: The thermophysical properties of binary mixtures containing water, ethanol, or propan-1-ol and cholinium l-alaninate ([Ch][Ala]), a type of choline amino acid ionic liquid (CAAIL), were studied. The influences of ionic liquid mole fraction and temperature on the properties were investigated, and excess volumes were calculated. The temperature effects on the density, dynamic viscosity, and refractive index of the synthesized [Ch][Ala] were also evaluated.
JOURNAL OF CHEMICAL AND ENGINEERING DATA
(2023)
Article
Biotechnology & Applied Microbiology
Silvia Castro Coelho, Audrey Giron, Fernando Rocha, Berta Nogueiro Estevinho
Summary: This study focuses on the encapsulation of B-complex vitamins using an electrohydrodynamic technique and zein as the wall material. The encapsulated vitamins showed enhanced antioxidant activity and similar release profiles. The microstructures produced were spherical and had high encapsulation efficiency. The study suggests that these encapsulation microsystems are suitable for protecting sensitive bioactive ingredients.
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Filipa Teixeira, Ana Margarida Silva, Stefania Sut, Stefano Dall'Acqua, Cristina Delerue-Matos, Berta Estevinho, Paulo C. Costa, Francisca Rodrigues
Summary: The aim of this study was to produce polymeric particles of Actinidia arguta leaves extract by spray-drying to improve the condition of oral mucositis. The results showed that the extract microparticles had good antioxidant and antiradical activities, and no adverse effects on oral cells, highlighting their potential applications in the pharmaceutical and nutraceutical industries.
Review
Materials Science, Multidisciplinary
Anabela Veiga, Sara Madureira, Joao B. Costa, Filipa Castro, Fernando Rocha, Ana L. Oliveira
Summary: Hydroxyapatite (HAp) based biomaterials have been widely used in biomedical applications, but manufacturing reproducible materials and process scalability are still challenges. Recent efforts have focused on enhancing HAp systems through combination with other materials, growth factors, and cells. 3D printing technology allows for the production of complex structures with high resolution and on-demand production, but limitations associated with HAp characteristics need to be overcome. Continuous production can achieve high volume manufacturing of HAp with uniform properties for 3D printing.
MATERIALS ADVANCES
(2023)
Review
Materials Science, Paper & Wood
Faezeh Fathi, Samad N. Ebrahimi, Fernando Rocha, Berta N. Estevinho
Summary: Medicinal plants have been important in healthcare and culture, and their bioactive compounds can offer potential health benefits. However, their poor bioavailability can be improved through encapsulation, which enhances their functionality and reduces dosage.
CELLULOSE CHEMISTRY AND TECHNOLOGY
(2022)
Article
Pharmacology & Pharmacy
Faezeh Fathi, Samad N. Ebrahimi, David M. Pereira, Berta N. Estevinho, Fernando Rocha
Summary: Encapsulation by spray drying is a promising technique that can protect phenolic compounds and improve their bioavailability and release time. Gum Arabic and pectin have different release times, and the best kinetic model is the Korsmeyer model.
PHARMACEUTICAL SCIENCES
(2022)