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1.
An Acad Bras Cienc ; 95(suppl 1): e20220552, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37585969

RESUMEN

A fibrinolytic enzyme from the microalga Dunaliella tertiolecta was produced under mixotrophic conditions using different corn steep liquor (CSL) concentrations ( 0 ≤ CLS ≤ 0.75%), purified using a combination of salting out and ion-exchange chromatography, and then biochemical characterized. Cultivation of this microalga using 0.5% CSL led to the highest maximum cell concentration (1.960±0.010 mg L-1) and cell productivity (0.140g L-1 day-1), besides a high fibrinolytic activity of the extract obtained by the homogenization method (102 ±1 U mL-1). The enzyme extracted from the microalgal biomass was 5-fold purified with a 20% yield and was found to have a specific activity of 670 U mg-1. The enzyme, whose molecular weight determined by fibrin zymography was 10 kDa, was shown to be stable at pH 3.0-9.0 and up to 70°C with optimal pH and temperature values of 8.0 and 50°C, respectively. When compared to other fibrinolytic enzymes, this protease stood out for its high fibrinolytic activity, which was enhanced by Fe2+, inhibited by Zn2+, Cu2+, Mg2+, and Ca2+, and strongly inhibited by phenylmethylsulfonyl fluoride, suggesting that it belongs to the serine metalloprotease family. Moreover, thanks to its thermal stability, the enzyme may be easily preserved and activated under high-temperature conditions.


Asunto(s)
Microalgas , Zea mays , Análisis Costo-Beneficio , Fibrina , Concentración de Iones de Hidrógeno , Temperatura
2.
An Acad Bras Cienc ; 94(4): e20201914, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36102391

RESUMEN

Fibrinolytic enzymes are considered promising alternative in the treatment of cardiovascular diseases by preventing fibrin clots. A protease from Mucor subtilissimus UCP 1262 was obtained by solid state fermentation and purified by ion exchange chromatography. The purified extract was administered at an acute dose of 2000 mg/mL to evaluate its toxic effects to the lungs of mice. After 14 days of treatment, a histomorphometric study was performed by the type 1 and 2 pneumocyte count and the evaluation of the lung area. As result, the experimental group showed a significant decrease of type 2 pneumocyte and although a decrease in the alveolar area was observed in relation to the control group, no significant pulmonary toxicity, emphysema, and fibrosis characteristics were detected. The in vitro tests suggest possible clinical applications for the enzyme.


Asunto(s)
Pulmón , Péptido Hidrolasas , Animales , Ratones , Péptido Hidrolasas/química
3.
An Acad Bras Cienc ; 94(4): e20201438, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35830020

RESUMEN

This work aimed to compare the production of collagenolytic proteases produced by M. subtilissimus UCP1262 in submerged fermentation (SF) and solid-state fermentation (SSF) as well as extracting in aqueous two-phase system (ATPS). Collagenolytic protease production was performed in using MS-2 culture medium (SF) and soybean bran as substrate (SSF). Subsequently, the fermented liquid from both fermentations were used for the extraction of enzyme by ATPS, it was verified the influence of different variables from a factorial design 23. In SSF the highest protease and collagenolytic activities were achieved with 362.66 U/mL and 179.81 U/mL, respectively. When compared with SF (26.33 and 18.70 U/mL) higher values were obtained in the activities. The protease partitioning from SF and SSF in ATPS showed a similar profile showing higher affinity for the polymer rich phase. The highest value for the response variable purification factor (3.49) was obtained in the system using SSF. Thus, SSF shows promise as a bioprocess for extracellular production of collagenolytic proteases, using of soybean bran as substrate had used sustainable raw material, aiming application this possible enzyme in the treatment of burns and postoperative scarring.


Asunto(s)
Mucor , Péptido Hidrolasas , Fermentación , Glycine max , Temperatura
4.
An Acad Bras Cienc ; 93(suppl 4): e20210335, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34909841

RESUMEN

Fibrinolytic proteases are a promising alternative in the pharmaceutical industry, they are used in the treatment of cardiovascular diseases, especially thrombosis. Microorganisms are the most interesting source of fibrinolytic proteases. The aim of this study was the production of fibrinolytic protease from Streptomyces parvulus DPUA 1573, the recovery of the protease by aqueous two-phase system and partial biochemical characterization of the enzyme. The aqueous two-phase system was performed according to a 24-full factorial design using polyethylene glycol molar mass, polyethylene glycol concentration, citrate concentration and pH as independent variables. It was analyzed the effect of different ions, surfactants, inhibitors, pH and temperature on enzyme activity. The best conditions for purifying the enzyme were 17.5% polyethylene glycol 8,000, 15% Phosphate and pH 8.0, it was obtained a partition coefficient of 7.33, a yield of 57.49% and a purification factor of 2.10-fold. There was an increase in enzyme activity in the presence of Fe2+ and a decrease in the presence of $\beta$-Mercaptoethanol, phenylmethylsulfonyl fluoride and Iodoacetic acid. The optimum pH was 7.0 and the optimum temperature was 40 ºC. The purified protease exhibited a molecular mass of 41 kDa. The fibrinolytic protease from Streptomyces parvulus proved to be a viable option for the development of a possible drug with fibrinolytic action.


Asunto(s)
Péptido Hidrolasas , Streptomyces , Concentración de Iones de Hidrógeno , Fosfatos , Polietilenglicoles , Temperatura
5.
An Acad Bras Cienc ; 93(suppl 3): e20200867, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34586176

RESUMEN

Solid state fermentation is a promising technology largely used in biotechnology process and is a suitable strategy for producing low-cost enzymatic products. At the present study, a novel enzyme obtained through solid state fermentation using Aspergillus sydowii was herein purified and characterized. The fermentations used coffee ground residue as substrate and the crude enzyme was submitted through further purification steps of: acetonic precipitation, DEAE-Sephadex and Superdex G-75 column. Both crude and purified enzymes were submitted to biochemical characterization of their thermostability, optimal temperature and pH, effects of inhibitors and metal ions. A purified protease was obtained with yield of 5.9-fold and 53% recovery, with maximal proteolytic activity of 352.0 U/mL. SDS-PAGE revealed a band of protein at 47.0 kDa. The enzyme activity was abolished in the presence of phenyl-methyl sulfonyl fluoride and partially inhibited against Triton X-100 (78.0%). The optimal activity was found in pH 8.0 at 45°C of temperature. Besides, the enzyme showed stability between 35°C and 50°C. It was possible to determine appropriate conditions to the obtainment of thermostable proteases with biotechnological interest associated with a method that concomitantly shows excellent production levels and recovery waste raw material in a very profitable process.


Asunto(s)
Café , Péptido Hidrolasas , Aspergillus , Fermentación , Concentración de Iones de Hidrógeno , Peso Molecular , Temperatura
6.
Bioelectromagnetics ; 41(2): 113-120, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31872912

RESUMEN

Ultrasound has been applied for varied purposes as it provides additional mechanical energy to a system, and is still profitable and straightforward, which are advantages for industrial applications. In this work, ultrasonic treatments were applied to purified collagenase fractions from a fermented extract by Aspergillus terreus UCP 1276 aiming to evaluate the potential effect on collagen hydrolysis. The physical agent was evaluated as an inductor of collagen degradation and consequently as a producer of peptides with anticoagulant activity. The sodium dodecyl sulphate-polyacrylamide gel electrophoresis analyses were also carried out to compare the hydrolysis techniques. The ultrasound (40 kHz, 47.4 W/L) processing was conducted under the same conditions of pH and temperature at different times. The ultrasound-assisted reaction was accelerated in relation to conventional processing. Collagenolytic activity was enhanced and tested in the presence of phenylmethanesulfonyl fluoride inhibitor. Underexposure, the activity was enhanced, reaching more than 72.0% of improvement in relation to the non-exposed enzyme. A period of 30 min of incubation under ultrasound exposure was enough to efficiently produce peptides with biological activity, including anticoagulation and effect on prothrombin time at about 60%. The results indicate that low-frequency ultrasound is an enzymatic inducer with likely commercial applicability accelerating the enzymatic reaction. Bioelectromagnetics. 2020;41:113-120. © 2019 Bioelectromagnetics Society.


Asunto(s)
Anticoagulantes/farmacología , Aspergillus/enzimología , Colágeno/química , Colagenasas/metabolismo , Péptidos/química , Anticoagulantes/química , Catálisis , Colágeno/metabolismo , Colagenasas/química , Colagenasas/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Fermentación , Humanos , Hidrólisis , Péptidos/farmacología , Fluoruro de Fenilmetilsulfonilo/química , Fluoruro de Fenilmetilsulfonilo/farmacología , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , Hidrolisados de Proteína/química , Ultrasonido/métodos
7.
Appl Biochem Biotechnol ; 183(3): 765-777, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28349375

RESUMEN

In this work, chitosan-based films containing gelatin and chondroitin-4-sulfate (C4S) with and without ZnO particles were produced and tested in vitro to investigate their potential wound healing properties. Chitosans were produced from shrimp-head processing waste by alkaline deacetylation of chitin to obtain chitosans differing in molecular weight and degree of deacetylation (80 ± 0.5%). The film-forming solutions (chitosan, C4S and gelatin) and ZnO suspension showed no toxicity towards fibroblasts or keratinocytes. Chitosan was able to agglutinate red blood cells, and film-forming solutions induced no hemolysis. Film components were released into solution when incubated in PBS as demonstrated by protein and sugar determination. These data suggest that a stable, chitosan-based film with low toxicity and an ability to release components would be able to establish a biocompatible microenvironment for cell growth. Chitosan-based films significantly increased the percentage of wound healing (wound contraction from 65 to 86%) in skin with full-thickness excision when compared with control (51%), after 6 days. Moreover, histological analysis showed increased granulation tissue in chitosan and chitosan/gelatin/C4S/ZnO films. Chitosan-based biopolymer composites could be used for improved biomedical applications such as wound dressings, giving them enhanced properties.


Asunto(s)
Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Quitosano/química , Sulfatos de Condroitina/química , Gelatina/química , Cicatrización de Heridas/efectos de los fármacos , Óxido de Zinc/química , Células 3T3 , Animales , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Humanos , Masculino , Ratones , Ratas , Ratas Wistar , Staphylococcus aureus/efectos de los fármacos , Porcinos
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