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1.
Int J Biol Macromol ; 231: 123060, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36632961

RESUMO

This study aimed to prepare micro/nanocrystalline cellulose-loaded naringin (NAR) tablets and evaluate their neuro-protective/therapeutic potentials in Alzheimer's disease (AD) model. Micro/nanocellulose was prepared from different agro-wastes, and the different cellulose preparations were then used to formulate eight oral tablets of naringin micro/nanoparticles by direct compression. AD-like symptoms were induced in adult male Sprague Dawley rats by co-administration of 150 mg/kg AlCl3 and 300 mg/kg D-galactose (oral administration/one week), and NAR tablets were assessed for neuroprotective/therapeutic potentials in terms of behavioral changes, levels of neurodegenerative and inflammatory markers, brain redox status, neurotransmitter tones, and cortex/hippocampus histopathological alterations. NAR treatments have significantly reversed the neurotoxic effect of AlCl3 as demonstrated by improved spatial and cognitive memory functions and promoted antioxidant defense mechanisms in treated AD animals. Also, the neurodegeneration was markedly restrained as reflected by marked histopathological enhancement, and prevention/amelioration of neuropsychiatric disorders, besides the restorative effect on dysregulated neurotransmitters tone. Both NAR tablet forms showed an overall higher ameliorative effect compared to the DPZ reference drug. The formulated tablets represent promising neuroprotective/therapeutic agents for Alzheimer's disease.


Assuntos
Doença de Alzheimer , Fármacos Neuroprotetores , Ratos , Animais , Masculino , Doença de Alzheimer/tratamento farmacológico , Cloreto de Alumínio , Ratos Sprague-Dawley , Fármacos Neuroprotetores/farmacologia , Hipocampo , Comprimidos/uso terapêutico , Modelos Animais de Doenças
2.
Int J Biol Macromol ; 142: 564-573, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31747565

RESUMO

Peptic ulcer is one of the worldwide diseases where 10% of adults are affected by peptic ulcers at least once in their lifetime. The goal of this study was to evaluate the effect of levan in treating peptic ulcer. The bacterial honey isolates called Bacillus sp. levan was utilized. Levan was chemically characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), 1H and 13C NMR analysis. Levan was used to treat gastric ulcers induced in rats by oral administration of 5 mL/kg ethanol. Microscopic examination of stomach sections indicated that treatment with 200 mg/kg levan effectively healed the ulcers. Levan had no antimicrobial activity against a common cause of ulcers such as Helicobacter pylori bacteria. Rather, we proposed that the high adhesion (manifested as a protective coating) and prebiotic activity of levan may account for the observed beneficial effects. The immunohistochemical examination showed that levan led to a noticeable Bacillus sp. levan reduction in NF-κB in the upper gastric mucosa. The results concluded that the role of levan was more protective rather than preventive and suggested that levan could play a fundamental role in solving the peptic ulcer problems.


Assuntos
Bacillus/química , Frutanos/isolamento & purificação , Frutanos/farmacologia , Mel/microbiologia , Úlcera Péptica/tratamento farmacológico , Animais , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Adesão Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Frutanos/uso terapêutico , Masculino , Úlcera Péptica/metabolismo , Ratos , Ratos Sprague-Dawley
3.
J Basic Microbiol ; 59(10): 1004-1015, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31407369

RESUMO

Screening of 18 bacterial honey isolates revealed that all the isolates were levansucrase producers. The most potent isolate that achieved the highest activity (45.66 U/ml) was identified as Bacillus subtilis NRC based on morphological examination and 16S rRNA. The results recorded the necessity of starch (5 g/L), baker's yeast (12.5 g/L), and AlCl3 (5 mM) in improvement of the enzyme productivity. The Bacillus subtilis levansucrase was eluted as a single protein in one purification step. The enzyme molecular weight was (14 kDa). It showed its optimum activity at 45°C and could retain 60% of its activity after incubation at 50°C for 2 h. Its optimum activity was obtained at pH 8.2 and the enzyme showed great pH stability in both acidic and alkaline ranges. Unlike, most levansucrases all tested metals had an adverse effect in enzyme activity. The enzyme had antioxidant activities and were characterized as spherical micro- and nanoparticles by transmission electron microscopy. The effect of growth conditions and medium composition in levan structure and its fibrinolytic activity was evaluated.


Assuntos
Bacillus subtilis/metabolismo , Frutanos/metabolismo , Hexosiltransferases/química , Hexosiltransferases/metabolismo , Aminoácidos , Antioxidantes/metabolismo , Bacillus subtilis/citologia , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Carboidratos , Meios de Cultura , Estabilidade Enzimática , Fibrinolíticos/metabolismo , Hexosiltransferases/isolamento & purificação , Hexosiltransferases/ultraestrutura , Mel/microbiologia , Concentração de Íons de Hidrogênio , Peso Molecular , RNA Ribossômico 16S/genética , Sais/metabolismo , Temperatura
4.
J Biosci Bioeng ; 127(6): 655-662, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30795878

RESUMO

This study focused on kinetics of levan yield by Bacillus subtilis M, in a 150 L stirred tank bioreactor under controlled pH conditions. The optimized production medium was composed of (g/L): commercial sucrose 100.0, yeast extract 2.0, K2HPO4 3.0 and MgSO4⋅7H2O 0.2; an increase in both carbohydrates consumption and cell growth depended on increasing the size of the stirred tank bioreactor from 16 L to 150 L. The highest levansucrase production (63.4 U/mL) and levan yield of 47 g/L was obtained after 24 h. Also, the specific levan yield (Yp/x) which reflects the cell productivity increased with the size increase of the stirred tank bioreactor and reached its maximum value of about 29.4 g/g cells. These results suggested that B. subtilis M could play an important role in levan yield on a large scale in the future. Chemical modifications of B. subtilis M crude levan (CL) into sulfated (SL), phosphorylated (PL), and carboxymethylated levans (CML) were done. The difference in CL structure and its derivatives was detected by FT-IR transmission spectrum. The cytotoxicity of CL and its derivatives were evaluated by HepGII, Mcf-7 and CaCo-2. In general most tested levans forms had no significant cytotoxicity effect. In fact, the carboxymethylated and phosphrylated forms had a lower anti-cancer effect than CL. On the other hand, SL had the highest cytotoxicity showing SL had a significant anti-cancer effect. The results of cytotoxicity and cell viability were statistically analyzed using three-way ANOVA.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Bacillus subtilis/metabolismo , Frutanos/química , Frutanos/farmacologia , Antineoplásicos/metabolismo , Reatores Biológicos , Biotecnologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Frutanos/biossíntese , Humanos
5.
Carbohydr Polym ; 96(1): 332-41, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23688489

RESUMO

Bacillus subtilis NRC1aza produced levansucrase under solid state fermentation using starch as support. A sequential optimization strategy, based on statistical experimental designs is employed to enhance enzyme productivity. First, a 2-level Plackett-Burman design was applied for bioprocess parameters screen that significantly increase levansucrase production. Second optimization step was performed using fractional factorial design in order to optimize the amounts of highest positive variables that had significant effect on levansucrase productivity. Maximal enzyme productivity of 170 U/gds was achieved in presence of glucose, yeast extract, and pH 8. In vitro, experiments confirmed that LevCR and LevQT had an antitumor activity against different animal and human cancer cell lines by demonstrating inhibitory effects on growth of Ehrlich ascites carcinoma cell line, human MCF-7 breast and liver HepG2 cancer cell lines, in particular LevQT was found to be efficacious compared to anticancer drug, cisplatin. Result focused in LevCR as strong fibrinolytic agent.


Assuntos
Bacillus subtilis/enzimologia , Hexosiltransferases/metabolismo , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Carcinoma de Ehrlich/tratamento farmacológico , Feminino , Fermentação , Frutanos/farmacologia , Frutanos/uso terapêutico , Células Hep G2 , Hexosiltransferases/farmacologia , Hexosiltransferases/uso terapêutico , Humanos , Células MCF-7 , Camundongos
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