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1.
J Vet Dent ; 41(3): 225-234, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37644824

RESUMO

Cleft palates are oral deformities that mostly affect puppies. They are frequently extensive and characterized by bone and palatal mucosa malformation. This deformity is a serious condition that may result in the death of the dog, therefore surgical treatment is recommended. Tissue bioengineering has emerged as a valuable option to treat cleft palates by applying acellular biological scaffolds as grafts. This case report proposed a new approach for surgical correction of canine cleft palate through a grafting technique using a decellularized scaffold. A decellularized portion of skin was implanted to correct a large cleft palate in a 3-month-old female Pug dog. The skin fragment was obtained from a dog cadaver and a decellularization protocol was performed. Under general anesthesia, a bilateral mucoperiosteal separation of the entire length of cleft margins was performed, and the scaffold was then positioned between the tissue and the bone palate. The interaction of the grafted scaffold with the oral mucosa and palatine layers resulted in total cleft closure, without postsurgical rejection or infection, indicating the applicability of this technique in dog's cleft palate correction. This is the first reported case demonstrating this new technique, which resulted in full cleft closure and healing.


Assuntos
Fissura Palatina , Doenças do Cão , Cães , Animais , Feminino , Fissura Palatina/cirurgia , Fissura Palatina/veterinária , Mucosa Bucal/cirurgia
2.
Enzyme Microb Technol ; 170: 110300, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37523882

RESUMO

This review emphasizes the crucial role of enzyme immobilization technology in advancing the production of two main biofuels, ethanol and biodiesel, with a specific focus on the Cross-linked Enzyme Aggregates (CLEAs) strategy. This method of immobilization has gained attention due to its simplicity and affordability, as it does not initially require a solid support. CLEAs synthesis protocol includes two steps: enzyme precipitation and cross-linking of aggregates using bifunctional agents. We conducted a thorough search for papers detailing the synthesis of CLEAs utilizing amylases, cellulases, and hemicellulases. These key enzymes are involved in breaking down starch or lignocellulosic materials to produce ethanol, both in first and second-generation processes. CLEAs of lipases were included as these enzymes play a crucial role in the enzymatic process of biodiesel production. However, when dealing with large or diverse substrates such as lignocellulosic materials for ethanol production and oils/fats for biodiesel production, the use of individual enzymes may not be the most efficient method. Instead, a system that utilizes a blend of enzymes may prove to be more effective. To innovate in the production of biofuels (ethanol and biodiesel), enzyme co-immobilization using different enzyme species to produce Combi-CLEAs is a promising trend.


Assuntos
Biocombustíveis , Enzimas Imobilizadas , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Tecnologia , Etanol , Reagentes de Ligações Cruzadas
3.
An Acad Bras Cienc ; 94(1): e20200752, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35043852

RESUMO

The use of ß-galactosidase in food products has been a major focus of the industry. Therefore, the development of efficient and inexpensive methodologies to purify it is essential. Thus, this study aimed to recover the enzyme ß-galactosidase (ß-gal) by ion-exchange chromatography in a fixed-bed column. Batch adsorption tests were performed using four types of adsorbents. The ß-gal adsorption capacity in batch mode using Streamline DEAE resin presented the best performance, with a retention capacity of 18.77 ± 0.14 U/g at pH 6.0. A 22 experimental design was applied to optimize the ß-gal recovery using an AKTA Start system, evaluating the ionic strength and the pH as process parameters. The results showed that ionic strength exerted a greater influence on fold purification (FP). The ß-gal fraction in elution using 0.1-0.4 M of NaCl showed a yield of 51.65 ± 0.17% and FP of 2.00 ± 0.43. Electrophoresis confirmed the ß-gal recovery, where an evident band with a molecular weight between 60 and 120 kDa was observed. These results point to the recovery of a stable ß-gal of K. lactis with potential industrial applications.


Assuntos
beta-Galactosidase , Cromatografia por Troca Iônica , Concentração de Íons de Hidrogênio , Kluyveromyces , Concentração Osmolar
4.
Prep Biochem Biotechnol ; 52(4): 443-451, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34370621

RESUMO

Chitooligosaccharides (COS) have a great potential to be used by pharmaceutical industry due to their many biological activities. The use of enzymes to produce them is very advantageous, however it still faces many challenges, such as discovering new strains capable to produce enzymes that are able to generate bioactive oligosaccharides. In the present study a purification protein protocol was performed to purify chitosanases produced by Bacillus toyonensis CCT 7899 for further chitosan hydrolysis. The produced chitooligosaccharides were characterized by mass spectroscopy (MS) and their antiedematogenic effect was investigated through carrageenan-induced paw edema model. The animals were treated previously to inflammation by intragastric route with COS at 30, 300 and 600 mg/kg. The purification protocol showed a good performance for the chitosanases purification using 0.20 M NaCl solution to elute it, with a 9.54-fold purification factor. The treatment with COS promoted a decrease of paw edema at all evaluated times and the AUC0-4h, proving that COS produced showed activity in acute inflammation like commercial anti-inflammatory Dexamethasone (corticosteroid). Therefore, the strategy used to purification was successfully applied and it was possible to generate bioactive oligosaccharides with potential pharmacological use.


Assuntos
Bacillus , Quitosana , Animais , Bacillus/metabolismo , Quitina/metabolismo , Quitosana/química , Edema/induzido quimicamente , Edema/tratamento farmacológico , Glicosídeo Hidrolases/metabolismo , Inflamação , Oligossacarídeos/metabolismo
5.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638973

RESUMO

The search for promising biomolecules such as chitooligosaccharides (COS) has increased due to the need for healing products that act efficiently, avoiding complications resulting from exacerbated inflammation. Therefore, this study aimed to produce COS in two stages of hydrolysis using chitosanases derived from Bacillus toyonensis. Additionally, this study aimed to structurally characterize the COS via mass spectrometry, to analyze their biocompatibility in acute toxicity models in vivo, to evaluate their healing action in a cell migration model in vitro, to analyze the anti-inflammatory activity in in vivo models of xylol-induced ear edema and zymosan-induced air pouch, and to assess the wound repair action in vivo. The structural characterization process pointed out the presence of hexamers. The in vitro and in vivo biocompatibility of COS was reaffirmed. The COS stimulated the fibroblast migration. In the in vivo inflammatory assays, COS showed an antiedematogenic response and significant reductions in leukocyte migration, cytokine release, and protein exudate. The COS healing effect in vivo was confirmed by the significant wound reduction after seven days of the experiment. These results indicated that the presence of hexamers influences the COS biological properties, which have potential uses in the pharmaceutical field due to their healing and anti-inflammatory action.


Assuntos
Anti-Inflamatórios/administração & dosagem , Materiais Biocompatíveis/administração & dosagem , Quitosana/administração & dosagem , Otopatias/tratamento farmacológico , Edema/tratamento farmacológico , Oligossacarídeos/administração & dosagem , Cicatrização/efeitos dos fármacos , Células 3T3 , Animais , Anti-Inflamatórios/química , Bacillus/enzimologia , Materiais Biocompatíveis/química , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Citocinas/metabolismo , Modelos Animais de Doenças , Otopatias/induzido quimicamente , Edema/induzido quimicamente , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Glicosídeo Hidrolases/química , Hidrólise , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligossacarídeos/química
6.
Prep Biochem Biotechnol ; 51(7): 714-722, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33287624

RESUMO

The present study aimed to evaluate the lactose hydrolysis conditions from "coalho" cheese whey using ß-galactosidase (ß-gal) produced by Kluyveromyces lactis immobilized with sodium alginate. Three sodium alginate-based immobilization systems were evaluated (0.5, 0.7, and 1% w/v) for maximizing the immobilization yield (Y), efficiency (EM), and recovered activity (ar). The lactose hydrolysis capacity of the immobilized form of ß-gal was determined, and simulated environments were used to assess the preservation of the immobilized enzyme in the gastrointestinal tract. The results showed that ß-gal immobilization with 1% (w/v) sodium alginate presented the best results (EM of 66%, Y of 41%, and ar of 65%). The immobilization system maintained the highest pH stability in the range between 5.0 and 7.0, with the highest relative activity obtained under pH 5 conditions. The temperature stability was also favored by immobilization at 50 °C for 30 min was obtained a relative activity of 180.0 ± 1.37%. In 6 h, the immobilized ß-gal was able to hydrolyze 46% of the initial lactose content. For the gastrointestinal simulations, around 40% of the activity was preserved after 2 h. Overall, the results described here are promising for the industrial applications of ß-galactosidase from K. lactis.


Assuntos
Alginatos/química , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Kluyveromyces/enzimologia , Lactose/química , beta-Galactosidase/química , Estabilidade Enzimática , Temperatura Alta , Concentração de Íons de Hidrogênio , Hidrólise
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