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1.
3 Biotech ; 12(11): 285, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36276456

RESUMO

Immobilization is a key technology that improves the operational stability of enzymes. In this study, alginate-gelatin (Alg-Gel) hydrogel matrix was synthesized and used as immobilization support for Mucor racemosus lipase (Lip). Enzyme catalyzed ultrasound-assisted hydrolysis of olive oil was also investigated. Alg-Gel matrix exhibited high entrapment efficiency (94.5%) with a degradation rate of 42% after 30 days. The hydrolysis of olive oil using Alg-Gel-Lip increased significantly (P < 0.05) as compared to free Lip. Optimum pH and temperature were determined as pH 5.0 and 40 °C, respectively. The Vmax values for free and immobilized Lip were determined to be 5.5 mM and 5.8 mM oleic acid/min/ml, respectively, and the Km values were 2.2 and 2.58 mM/ml respectively. Thermal stability was highly improved for Alg-Gel-Lip (t1/2 650 min and Ed 87.96 kJ/mol) over free Lip (t1/2 150 min and Ed 23.36 kJ/mol). The enzymatic activity of Alg-Gel-Lip was preserved at 96% after four consecutive cycles and 90% of the initial activity after storage for 60 days at 4 °C. Alg-Gel-Lip catalyzed olive oil hydrolysis using ultrasound showed a significant (P < 0.05) increase in hydrolysis rate compared to free Lip (from 0.0 to 58.2%, within the first 2 h). In contrast to traditional methodology, using ultrasonic improved temperature-dependent enzymatic catalyzed reactions and delivered greater reaction yields. Results suggest that Alg-Gel-Lip biocatalyst has great industrial application potential, particularly for free fatty acid production. In addition, the combined use of enzyme and ultrasound has the potential of eco-friendly technology.

2.
3 Biotech ; 12(3): 73, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35211369

RESUMO

Hydrogel-based matrix prepared using biopolymers is a new frontier of emerging platforms for enzyme immobilization for biomedical applications. Catalase (CAT) delivery can be effective in inhibiting reactive oxygen species (ROS)-mediated prolongation of the wound healing process. In this study, to improve CAT stability for effective application, gelatin(Gel)-alginate (Alg) biocompatible hydrogel (Gel-Alg), as immobilization support, was prepared using calcium chloride as an ionic cross-linker. High entrapment efficiency of 92% was obtained with 2% Gel and 1.5% Alg. Hydrogel immobilized CAT (CAT-Gel-Alg) showed a wide range of pH from 4 to 9 and temperature stability between 20 to 60 °C, compared to free CAT. CAT-Gel-Alg kinetic parameters revealed an increased K m (24.15 mM) and a decreased V max (1.39 µmol H2O2/mg protein min) × 104. CAT-Gel-Alg retained 52% of its original activity after 20 consecutive catalytic runs and displayed improved thermal stability with a higher t 1/2 value (half-life of 100.43 vs. 46 min). In addition, 85% of the initial activity was maintained after 8 weeks' storage at 4 °C. At 24 h after thermal injury, a statistically significant difference in lesion sizes between the treated group and the control group was reported. Finally, our findings suggest that the superior CAT-Gel-Alg stability and reusability are resonant features for efficient biomedical applications, and ROS scavenging by CAT in the post-burn phase offers protection for local treatment of burned tissues with encouraging wound healing kinetics.

3.
J Microencapsul ; 38(6): 414-436, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34157915

RESUMO

The fast progress in nanomedicine and nanoparticles (NP) materials presents unconventional solutions which are expected to revolutionise health care with great potentials including, enhanced efficacy, bioavailability, drug targeting, and safety. This review provides a comprehensive update on widely used organic and inorganic NP with emphasis on the recent development, challenges and future prospective for bio applications where, further investigations into innovative synthesis methodologies, properties and applications of NP would possibly reveal new improved biomedical relevance. NP exhibits exceptional physical and chemical properties due to their high surface area to volume ratio and nanoscale size, which led to breakthroughs in therapeutic, diagnostic and screening techniques repeated line. Finally, an update of FDA-approved NP is explored where innovative design engineering allowed a paradigmatic shift in their market share. This review would serve as a discerning comprehensive source of information for learners who are seeking a cutting-edge review but have been astounded by the size of publications.


Assuntos
Nanomedicina , Nanopartículas , Sistemas de Liberação de Medicamentos
4.
J Med Biochem ; 38(4): 427-436, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31496906

RESUMO

BACKGROUND: Recent studies suggest asthma prevalence in polycystic ovary syndrome (PCOS) patients. This is the first study to explore asthma prevalence among Egyptian PCOS patients. It highlighted common findings in PCOS and asthma. It investigated whether these findings could serve as potential predictors of asthma. METHODS: A hundred PCOS patients, sixty asthmatic patients and thirty apparently healthy females of matched age were included. Body mass index (BMI), C-reactive protein (CRP), IL-6, IgE, 25 (OH) vitamin D, testosterone and lipid profile were measured. RESULTS: Both PCOS and asthmatics had significantly higher BMI, Total cholesterol (TC), LDL-C, IgE, CRP and IL-6 (P<0.001) and lower 25 (OH) vitamin D levels (P<0.001) compared to controls. Within the PCOS group, 47 patients developed asthma with a significant increase in BMI (P=0.003), CRP and IgE levels (P<0.001) compared to non-asthmatic PCOS. Both asthmatic PCOS and asthmatics expressed elevated BMI, IgE, IL-6 and CRP levels, but with no significant difference between them. Asthmatic PCOS showed significantly higher testosterone and dyslipidemia profile. Multivariate regression revealed that BMI and CRP could predict asthma development within PCOS (OR=1.104, C.I 1.004-1.2 and OR=1, C.I. 1-1.02), respectively. Receiver operating characteristic (ROC) curve showed that BMI and CRP at a cutoff value 28.5 kg/m2 and 117.6 nmol/L respectively could differentiate between asthmatic and non-asthmatic PCOS with sensitivity 63.8 % and specificity 62% for BMI, and sensitivity and specificity of 66% for CRP. CONCLUSIONS: This study shows that BMI and CRP are predictors of asthma development in Egyptian PCOS.

5.
Artif Cells Nanomed Biotechnol ; 47(1): 2361-2368, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31190563

RESUMO

Enzymes are powerful versatile biocatalysts, however, industrial application of enzymes is usually hampered by their susceptibility. Bio-inspired Eudragit-α-amylase conjugate (E-AC) was proposed as a biocatalyst for various pharmaceutical and industrial applications. In this study, α -Amylase (E.C. 3.2.1.1) was immobilized by covalent conjugation to Eudragit L-100 under mild conditions. The effect of polymer, carbodiimide and enzyme concentrations on optimization of (E-AC) was investigated. In addition, characterization of the free α -Amylase and E-AC with regard to pH, temperature, kinetic parameters, reusability and operational and storage conditions was carried out. Results showed a shift of the optimum pH of E-AC towards the alkaline side whereas, E-AC exhibited higher thermal stability at all tested temperatures. The kinetic parameters, Km values were 2.87 mg/ml and 3.15 mg/ml and Vmax values were 8.35 mg/ml/min and 8.98 mg/ml/min for free and E-AC, respectively. E-AC retained 85% of the initial activity after five consecutive amylolytic cycles, thus emphasizing its powerful potentials. Operational storage and thermal stability were highly improved as well for E-AC conjugate with an 11.6 stabilization factor in comparison to the free α-amylase. In this study, Eudragit L-100 polymer was successfully used as smart immobilization support to create a reversibly soluble-insoluble enzyme biocatalyst to enforce and extend biotechnological applications of α-amylase in the pharmaceutical industry.


Assuntos
Acrilatos/química , Biocatálise , Indústria Farmacêutica , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Polímeros/química , alfa-Amilases/química , alfa-Amilases/metabolismo , Animais , Custos e Análise de Custo , Indústria Farmacêutica/economia , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Temperatura
6.
Artif Cells Nanomed Biotechnol ; 46(sup1): 362-371, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29336165

RESUMO

One of the main challenges for successful pharmaceutical application of Catalase (CAT) is maintaining its stability. Physical immobilization of CAT through nano-encapsulation was proposed to resolve this challenge. CAT encapsulating niosomes (e-CAT) were prepared using Brij® 30, 52, 76, 92, and 97 in the presence of cholesterol (Ch) by thin film hydration method. Niosomes were characterized for encapsulation efficiency % (EE), size, poly-dispersity index (PI), and morphology. Kinetic parameters, pH optimum, thermal stability, and reusability of CAT were determined. The influence of optimized e-CAT dispersion onto thermally injured rat skin was evaluated. Results revealed that encapsulation enhanced CAT catalytic efficiency (Vmax/Km). Free CAT and e-CAT had pH optimum at 7.0. e-CAT exhibited improved thermal stability where it retained 50% residual activity at 60 °C. Free CAT lost its activity after three consecutive operational cycles; however, e-CAT retained 60% of its initial activity following 12 cycles. After 24 h of topical application on thermal injury, a significant difference in lesion size was observed with e-CAT compared with the control group. Based on these encouraging results, CAT immobilization demonstrated a promising novel delivery system that enhances its operational stability. In addition, nano-encapsulated CAT can be anticipated to be beneficial in skin oxidative injury.


Assuntos
Catalase/química , Catalase/farmacologia , Portadores de Fármacos/química , Nanoestruturas/química , Pele/efeitos dos fármacos , Pele/metabolismo , Animais , Cápsulas , Bovinos , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/farmacologia , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Lipossomos/química , Masculino , Oxirredução , Ratos , Ratos Wistar , Pele/lesões , Temperatura , Cicatrização/efeitos dos fármacos
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