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1.
Int J Mol Sci ; 25(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38732010

RESUMO

L-asparaginase is an essential drug used to treat acute lymphoid leukemia (ALL), a cancer of high prevalence in children. Several adverse reactions associated with L-asparaginase have been observed, mainly caused by immunogenicity and allergenicity. Some strategies have been adopted, such as searching for new microorganisms that produce the enzyme and applying protein engineering. Therefore, this work aimed to elucidate the molecular structure and predict the immunogenic profile of L-asparaginase from Penicillium cerradense, recently revealed as a new fungus of the genus Penicillium and producer of the enzyme, as a motivation to search for alternatives to bacterial L-asparaginase. In the evolutionary relationship, L-asparaginase from P. cerradense closely matches Aspergillus species. Using in silico tools, we characterized the enzyme as a protein fragment of 378 amino acids (39 kDa), including a signal peptide containing 17 amino acids, and the isoelectric point at 5.13. The oligomeric state was predicted to be a homotetramer. Also, this L-asparaginase presented a similar immunogenicity response (T- and B-cell epitopes) compared to Escherichia coli and Dickeya chrysanthemi enzymes. These results suggest a potentially useful L-asparaginase, with insights that can drive strategies to improve enzyme production.


Assuntos
Asparaginase , Simulação por Computador , Penicillium , Asparaginase/química , Asparaginase/imunologia , Asparaginase/metabolismo , Penicillium/imunologia , Penicillium/enzimologia , Sequência de Aminoácidos , Proteínas Fúngicas/química , Proteínas Fúngicas/imunologia , Proteínas Fúngicas/metabolismo , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito B/química , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/química , Humanos , Aspergillus/imunologia , Aspergillus/enzimologia , Escherichia coli/genética , Dickeya chrysanthemi/enzimologia , Dickeya chrysanthemi/imunologia , Modelos Moleculares
2.
Bol. latinoam. Caribe plantas med. aromát ; 21(2): 156-175, mar. 2022. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1393371

RESUMO

The purpose of this systematic review was to identify the available literature on the essential oil from species of genus Cordia. This study followed the Preferred Reporting Items for Systematic Reviews. The search was conducted on four databases: LILACS, PubMed, Science Direct, and Scopus until June 5th, 2020, with no time or language restrictions. Sixty out of the 1,333 initially gathered studies fit the inclusion criteria after the selection process. Nine species of Cordia were reported in the selected studies, out of which 79% of the evaluated studies reported essential oil from Cordia curassavica. The essential oil extraction methods identified were hydrodistillation and steam distillation. As for biological application, antimicrobial, anti-inflammatory, larvicidal and antioxidant activities were the most reported. The main compounds reported for essential oil were ß-caryophyllene, α-humulene, α-pinene, bicyclogermacrene, and sabinene. The information reported in this systematic review can contribute scientifically to the recognition of the importance of the genus Cordia.


El propósito de esta revisión sistemática fue identificar la literatura disponible sobre el aceite esencial de especies del género Cordia. Este estudio siguió los elementos de informe preferidos para revisiones sistemáticas. La búsqueda se realizó en cuatro bases de datos: LILACS, PubMed, Science Direct y Scopus hasta el 5 de junio de 2020, sin restricciones de tiempo ni de idioma. Sesenta de los 1.333 estudios reunidos inicialmente cumplieron los criterios de inclusión después del proceso de selección. Se informaron nueve especies de Cordia en los estudios seleccionados, de los cuales el 79% de los estudios evaluados informaron aceite esencial de Cordia curassavica. Los métodos de extracción de aceite esencial identificados fueron la hidrodestilación y la destilación al vapor. En cuanto a la aplicación biológica, las actividades antimicrobianas, antiinflamatorias, larvicidas y antioxidantes fueron las más reportadas. Los principales compuestos reportados para el aceite esencial fueron ß-cariofileno, α-humuleno, α-pineno, biciclogermacreno y sabineno. La información reportada en esta revisión sistemática puede contribuir científicamente al reconocimiento de la importancia del género Cordia.


Assuntos
Óleos Voláteis/química , Cordia/química , Sesquiterpenos/análise , Destilação , Monoterpenos/análise
3.
Bol. latinoam. Caribe plantas med. aromát ; 20(4): 427-442, jul. 2021. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1369497

RESUMO

The objective of this study was to evaluate biological and phytochemical properties of the aqueous extract from the leaves of Miconia chamissois Naudin (AEMC). Phytochemical properties were assessed by analyzing the chromatographic profile and the polyphenol content of AEMC. Biological properties evaluation was conducted based on cytotoxicity assay and by evaluating the antioxidant, antimicrobial, and enzymatic inhibition activities. Results indicated the presence of phytochemicals in AEMC such as flavonoids and polyphenols, including rutin, isoquercitrin and vitexin derivatives. AEMC showed antioxidant activity, which may be attributed to the high polyphenolic content. Moreover, AEMC demonstrated in vitro enzyme inhibition activity against tyrosinase and alpha-amylase, as well as showed low cytotoxicity. On the other hand, AEMC exhibited weak antimicrobial activity against S. aureusand C. albicans. Thus, AEMC is a promising alternative in search of potential drugs for the treatment of diseases induced by oxidative stress and inflammation, conditions due to hyperpigmentation processes, such as melisma, as well as for diabetes.


El objetivo de este estudio fue detectar las propiedades biológicas y fitoquímicos del extracto acuoso de las hojas de Miconia chamissois Naudin (AEMC). Las propiedades fitoquímicas se evaluaron analizando el perfil cromatográfico y el contenido de polifenoles de AEMC. La evaluación de las propiedades biológicas se realizó en base al ensayo de citotoxicidad y evaluando las actividades de inhibición antioxidante, antimicrobiana y enzimática. Los resultados indicaron la presencia de fitoquímicos en AEMC, como flavonoides y polifenoles, que incluyen derivados de rutina, isoquercitrina y vitexina. AEMC mostró una actividad antioxidante considerable, que puede atribuirse al alto contenido polifenólico. Además, AEMC exhibió actividad de inhibición enzimática in vitro contra tirosinasa y alfa-amilasa, así como mostró baja citotoxicidad. Por otro lado, AEMC demostró actividad antimicrobiana débil contra S. aureusy C. albicans. Por lo tanto, AEMC es una alternativa prometedora en busca de posibles drogas para el tratamiento de enfermedades inducidas por el estrés oxidativo y la inflamación, afecciones debidas a procesos de hiperpigmentación, como el melasma, así como para la diabetes.


Assuntos
Extratos Vegetais/farmacologia , Extratos Vegetais/química , Melastomataceae/química , Flavonoides/análise , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Monofenol Mono-Oxigenase/antagonistas & inibidores , alfa-Amilases/antagonistas & inibidores , Polifenóis/análise , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia
4.
Enzyme Res ; 2018: 6597017, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29850226

RESUMO

Enzymatic hydrolysis is an important but expensive step in the process to obtain enzyme derived products. Thus, the production of efficient enzymes is of great interest for this biotechnological application. The production of xylanase by Aspergillus foetidus in soybean residues was optimized using 2 × 23 factorial designs. The experimental data was fitted into a polynomial model for xylanase activity. Statistical analyses of the results showed that variables pH and the interaction of pH and temperature had influenced the production of xylanase, with the best xylanase production level (13.98 U/mL) occurring at fermentation for 168 hours, pH 7.0, 28°C, and 120 rpm.

5.
Food Chem Toxicol ; 109(Pt 2): 962-969, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28288931

RESUMO

Type 2 diabetes plays a major role in public health, affecting about 400 million adults. One of the used strategies to control type 2 diabetes is the inhibition of α-amylase activity to reduce post-prandial blood glucose levels. Therefore, in past decades, the search of new α-amylase inhibitors has led to the evaluation of natural products as a source of these compounds. Pouteria torta (Sapotaceae) is widespread in Brazil and bears edible fruits. Epicarp and pulp crude extracts of fresh fruits were studied for in vitro α-amylase inhibition activity. The pulp did not present activity while epicarp, usually considered as waste, showed a high α-amylase inhibitory capacity when compared with acarbose and Triticum aestivum. Therefore, an assay-guided fractionation study of epicarp crude extract was performed. Fraction VI shows very high inhibitory activity with IC50 of 9 µg/mL. However, subsequent fractionation led to lower inhibition potential (IC50 of 22.1 µg/mL). The qualitative characterization of fraction VI were performed by chromatographic and spectrometric analysis and showed the presence of epicatechin, catechin, sucrose, glucose, and fructose. Total phenolic and flavonoid contents and antioxidant capacity were also assessed and there seemed to be no correlation between phenolic or flavonoids-rich fractions and antioxidant capacity or α-amylase inhibitory activity.


Assuntos
Diabetes Mellitus Tipo 2/enzimologia , Inibidores Enzimáticos/química , Extratos Vegetais/química , Pouteria/química , alfa-Amilases/antagonistas & inibidores , Antioxidantes/química , Brasil , Inibidores Enzimáticos/isolamento & purificação , Frutas , Humanos , Cinética , Extratos Vegetais/isolamento & purificação , alfa-Amilases/metabolismo
6.
Braz J Microbiol ; 46(2): 337-46, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26273247

RESUMO

Proteases hydrolyze the peptide bonds of proteins into peptides and amino acids, being found in all living organisms, and are essential for cell growth and differentiation. Proteolytic enzymes have potential application in a wide number of industrial processes such as food, laundry detergent and pharmaceutical. Proteases from microbial sources have dominated applications in industrial sectors. Fungal proteases are used for hydrolyzing protein and other components of soy beans and wheat in soy sauce production. Proteases can be produced in large quantities in a short time by established methods of fermentation. The parameters such as variation in C/N ratio, presence of some sugars, besides several other physical factors are important in the development of fermentation process. Proteases of fungal origin can be produced cost effectively, have an advantage faster production, the ease with which the enzymes can be modified and mycelium can be easily removed by filtration. The production of proteases has been carried out using submerged fermentation, but conditions in solid state fermentation lead to several potential advantages for the production of fungal enzymes. This review focuses on the production of fungal proteases, their distribution, structural-functional aspects, physical and chemical parameters, and the use of these enzymes in industrial applications.


Assuntos
Biotecnologia/métodos , Fungos/enzimologia , Peptídeo Hidrolases/isolamento & purificação , Peptídeo Hidrolases/metabolismo
7.
ScientificWorldJournal ; 2014: 439461, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25379532

RESUMO

This study aims at determining the Minimum Inhibitory Concentration with Escherichia coli ATCC 25922 and cytotoxicity to L929 cells (ATCC CCL-1) of the waste generated by doxycycline degradation by the Fenton process. This process has shown promise in this treatment thanks mainly to the fact that the waste did not show any relevant inhibitory effect on the test organism and no cytotoxicity to L-929 cells, thus demonstrating that the antibiotic properties were inactivated.


Assuntos
Antibacterianos/química , Doxiciclina/química , Peróxido de Hidrogênio/química , Ferro/química , Poluentes Químicos da Água/química , Animais , Antibacterianos/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Doxiciclina/toxicidade , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fibroblastos/efeitos dos fármacos , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/toxicidade
8.
Braz J Microbiol ; 41(4): 850-61, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24031565

RESUMO

Amylases are one of the main enzymes used in industry. Such enzymes hydrolyze the starch molecules into polymers composed of glucose units. Amylases have potential application in a wide number of industrial processes such as food, fermentation and pharmaceutical industries. α-Amylases can be obtained from plants, animals and microorganisms. However, enzymes from fungal and bacterial sources have dominated applications in industrial sectors. The production of α-amylase is essential for conversion of starches into oligosaccharides. Starch is an important constituent of the human diet and is a major storage product of many economically important crops such as wheat, rice, maize, tapioca, and potato. Starch-converting enzymes are used in the production of maltodextrin, modified starches, or glucose and fructose syrups. A large number of microbial α-amylases has applications in different industrial sectors such as food, textile, paper and detergent industries. The production of α-amylases has generally been carried out using submerged fermentation, but solid state fermentation systems appear as a promising technology. The properties of each α-amylase such as thermostability, pH profile, pH stability, and Ca-independency are important in the development of fermentation process. This review focuses on the production of bacterial and fungal α-amylases, their distribution, structural-functional aspects, physical and chemical parameters, and the use of these enzymes in industrial applications.

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