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1.
Curr Issues Mol Biol ; 45(9): 7617-7629, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37754263

RESUMO

Toxicological studies on medicinal plants are essential to ensure their safety and effectiveness in treating various diseases. Despite the species Chrysobalanus icaco L. being popularly used in the treatment of several diseases due to the pharmacological properties of its bioactive compounds, there are few studies in the literature regarding its toxicity regarding reproduction. Therefore, the purpose of this study was to assess the potential embryotoxic and teratogenic effects of the aqueous extract of C. icaco leaves (AECi) on Wistar rats. Animals were given AECi at doses of 100, 200, and 400 mg/kg during the pre-implantation and organogenesis periods. Data were analyzed using ANOVA followed by Tukey's test and Kruskal-Wallis. Pregnant rats treated during the pre-implantation period showed no signs of reproductive toxicity. Rats that received AECi at 100, 200, and 400 mg/kg during organogenesis did not exhibit any signs of maternal systemic toxicity or significant differences in gestational and embryotoxic parameters. Some skeletal changes were observed in the treated groups. Therefore, it can be suggested that AECi at doses of 100, 200, and 400 mg/kg is safe for treated animals and does not induce reproductive toxicity under the experimental conditions applied, but it also caused low systemic toxicity.

2.
An Acad Bras Cienc ; 94(1): e20200940, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35170628

RESUMO

Antioxidants present in many fruit residues can play an essential role in the prevention of diseases. The aim of this study was to determine nutritional and mineral composition, fatty acids profile, anti-nutrients, bioactive compounds, antioxidant activity and technological properties of flour from residues generated by umbu fruit processing. Nutritional composition showed high levels of dietary fiber, especially insoluble fiber (56.67%). The flour can be classified as a good source of calcium, phosphorus and magnesium, and an excellent source of iron, zinc and copper. Palmitic and stearic saturated fatty acids and oleic and linoleic unsaturated fatty acids were identified. No potentially toxic substances were detected. Significant values of ascorbic acid (44.78 mg/100g), carotenoids (463.73 µg/100g) and flavonoids (37.85 mg QE/100g) were found, as well as very high levels of phenolic compounds (20357.26 mg GAE/100g). Strong antioxidant activity was detected in the flour by three methods (ABTS, DPPH and FRAP) demonstrating a linear positive correlation between phenolic content and antioxidant activity. The flour showed high absorption of water, oil, emulsifying capacity and emulsion stability presenting a great potential for use in foods, especially meat, bakery and dairy products. These results indicate promising prospects to full use of umbu as a functional ingredient.


Assuntos
Anacardiaceae , Farinha , Antioxidantes , Flavonoides , Farinha/análise , Frutas
3.
Prep Biochem Biotechnol ; 50(7): 655-663, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32068481

RESUMO

The partitioning and purification of lectins from the crude extract of Cratylia mollis seeds (Cramoll 1,4) was investigated in aqueous two-phase systems (ATPS). A factorial design model (24) was used to evaluate the influence of polyethylene glycol (PEG) molar mass (1500-8000 g/mol), PEG concentration (12.5-17.5% w/w), phosphate (10-15% w/w) concentration, and pH (6-8) on the differential partitioning, purification factor, and yield of the lectin. Polymer and salt concentration were the most important variables affecting partition of lectin and used to find optimum purification factor by experimental Box-Behnken design together with the response surface methodology (RSM). ATPS showed best conditions composed by 13.9% PEG1500, 15.3% phosphate buffer at pH 6, which ensured purification factor of 4.70. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a single band of protein with 26.1 kDa. Furthermore, results demonstrated a thermostable lectin presenting activity until 60 °C and lost hemagglutinating activity at 80 °C. According to the obtained data it can be inferred that the ATPS optimization using RSM approach can be applied for recovery and purification of lectins.


Assuntos
Lectinas/química , Lectinas/isolamento & purificação , Phaseolus/química , Extratos Vegetais/química , Eletroforese em Gel de Poliacrilamida , Hemaglutininas/química , Concentração de Íons de Hidrogênio , Fosfatos/química , Polietilenoglicóis/química , Proteínas/química , Sementes/química , Espectrofotometria , Propriedades de Superfície , Temperatura
4.
J Food Sci Technol ; 54(5): 1304-1311, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28416881

RESUMO

The aim of this research was to evaluate the efficiency of liquid smoking and chitosan coating on the shelf life of Nile tilapia (Oreochromis niloticus) fillets. Fillets without liquid smoked and chitosan coating (control), liquid smoked fillets (LS), and liquid smoked and chitosan coated fillets (LSCh) were stored at 4 ± 1 °C for 30 days. The physicochemical (pH, moisture content, water activity-aw, color, texture, total volatile bases nitrogen-TVB-N and thiobarbituric acid reactive substances-TBARS) and microbiological analyses (mesophilic and psychrotrophic counts) and the electrophoresis profile of samples were carried out. Physicochemical parameters, such as TVB-N and TBARS, were reduced in the tilapia fillets with liquid smoking. The presence of the coating of chitosan was effective for the control of the microorganisms during storage. This work showed that the addition of a chitosan coating in liquid-smoked fillets further enhanced the effect of preservation.

5.
J Clin Microbiol ; 50(6): 1912-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22495562

RESUMO

Skin biopsy samples from 145 relapse leprosy cases and from five different regions in Brazil were submitted for sequence analysis of part of the genes associated with Mycobacterium leprae drug resistance. Single nucleotide polymorphisms (SNPs) in these genes were observed in M. leprae from 4 out of 92 cases with positive amplification (4.3%) and included a case with a mutation in rpoB only, another sample with SNPs in both folP1 and rpoB, and two cases showing mutations in folP1, rpoB, and gyrA, suggesting the existence of multidrug resistance (MDR). The nature of the mutations was as reported in earlier studies, being CCC to CGC in codon 55 in folP (Pro to Arg), while in the case of rpoB, all mutations occurred at codon 531, with two being a transition of TCG to ATG (Ser to Met), one TCG to TTC (Ser to Phe), and one TCG to TTG (Ser to Leu). The two cases with mutations in gyrA changed from GCA to GTA (Ala to Val) in codon 91. The median time from cure to relapse diagnosis was 9.45 years but was significantly shorter in patients with mutations (3.26 years; P = 0.0038). More than 70% of the relapses were multibacillary, including three of the mutation-carrying cases; one MDR relapse patient was paucibacillary.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Hanseníase/epidemiologia , Hanseníase/microbiologia , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Brasil/epidemiologia , DNA Bacteriano/química , DNA Bacteriano/genética , Feminino , Genes Bacterianos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Mutação Puntual , Polimorfismo de Nucleotídeo Único , Prevalência , Estudos Prospectivos , Recidiva , Análise de Sequência de DNA , Pele/microbiologia , Adulto Jovem
6.
Biotechnol Rep (Amst) ; 26: e00471, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32509541

RESUMO

This work describes the successful extraction of Aspergillus niger phytase from a crude extract (CE) obtained from solid-state fermentation by reversed micelle system using anionic surfactant sodium bis (2-ethylhexyl) sulfosuccinate (AOT) in isooctane achieved in two simple steps: forward and backward extractions. The effects of potassium chloride (KCl) concentration, pH of the aqueous solution, and AOT concentration that affect the system were examined. The best result for the forward extraction was obtained with the CE solution at pH 4.0, 50 mM KCl, and 100 mM AOT, while for the backward extraction the best result was achieved with a stripping aqueous solution at pH 5.5 containing 200 mM KCl, achieving a purification factor of 4.03, 1.15 times higher than that reported for the conventional purification process. Phytase purity was demonstrated by SDS-PAGE (89 kDa) and its activity by zymogram, confirming the efficiency of the process with low time consumption (∼40 min).

7.
Food Sci Technol Int ; 25(4): 318-326, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30646759

RESUMO

Microalgae are considered one of the most promising raw materials for the development of high value products for pharmaceuticals, nutraceuticals, and cosmetic industries, as well as being potential sources of protein, vitamins, and minerals for human consumption. Hence, the present research focuses extraction of antioxidant and antimicrobial compounds from Scenedesmus subspicatus using solvents of different polarities. Different solvents such as ethanol, methanol, butanol, acetone, dimethyl sulfoxide, and water were used to extract compounds from the green microalgae S. subspicatus and then they were examined for phytochemical screening, antioxidant activity, and antimicrobial properties. In vitro free radical quenching and total antioxidant activity of extracts were investigated with 1,1-diphenyl-2-picryl hydrazyl and compared with catequin and gallic acid as positive controls. The antimicrobial activity was evaluated in gram-negative and gram-positive bacteria. Aqueous extracts and dimethyl sulfoxide presented better performance in phytochemical analysis. This result showed consistency in the sequential tests. The antioxidant activity was also better using the two solvents cited above. The extracts acetone, water, and dimethyl sulfoxide showed ability to inhibit the growth of Bacillus subtilis. However, only dimethyl sulfoxide inhibited the growth of Klebsiella pneumoniae and Escherichia coli. Use of the aqueous extract, proven its effectiveness, is an economic protocol and avoids the use of toxic substances.


Assuntos
Antibacterianos/análise , Antioxidantes/análise , Microalgas/química , Extratos Vegetais/química , Scenedesmus/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Brasil , Ácido Gálico/análise , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/análise , Extratos Vegetais/farmacologia , Solventes , Taninos/análise
8.
Food Funct ; 9(4): 2456-2468, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29632933

RESUMO

Here we have proposed to evaluate potential replacers of fat in sponge cake formulations. Our investigation consisted initially of monitoring the physical-chemical changes in sponge cake batters caused by gradually replacing the vegetable fat/margarine of a control sample (standard sponge cake recipe) with galactomannan extracted from the seeds of Cassia grandis. Several samples were prepared where a 100% concentration of vegetable fat was substituted with galactomannan in different concentrations. We then compared both microscopic and macroscopic characteristics of pure fat cake batter formulations and formulations with controlled fat/galactomannan mixtures. At this first stage, rheometry and optical microscopy were employed to characterize the rheological features and air bubble distribution in the batters. In the second stage, the effects of fat substitution with galactomannan, now for the final baked cakes, were also monitored. Scanning electron microscopy (SEM) and standard sensorial tests were performed in order to correlate the final color, texture, and taste characteristics of the final sponge cake and those characteristics obtained initially for the batter. According to the statistical analysis of the data, a 75% fat replacement with galactomannan at only 1.0% concentration was achieved, while successfully maintaining surface microstructure, sensory acceptance, and rheological behavior similar to the original formulation containing only fat. Regarding vegetable fat substitution with galactomannan, our results allow us to conclude that rheometry and bubble distribution tests on the initial batters are useful indicators of the final cake quality.


Assuntos
Pão/análise , Cassia/química , Substitutos da Gordura/química , Mananas/química , Extratos Vegetais/química , Adolescente , Adulto , Culinária , Feminino , Farinha/análise , Galactose/análogos & derivados , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Reologia , Paladar , Viscosidade , Adulto Jovem
9.
Int J Biol Macromol ; 75: 402-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25668321

RESUMO

Apuleia leiocarpa is a tree found in Caatinga that has great value in the timber industry. Lectins are carbohydrate-binding proteins with several biotechnological applications. This study shows the isolation, characterization, and antibacterial activity of A. leiocarpa seed lectin (ApulSL). The lectin was chromatographically isolated from a crude extract (in 150 mM NaCl) by using a chitin column. ApulSL adsorbed to the matrix and was eluted using 1.0 M acetic acid. Native ApulSL was characterized as a 55.8-kDa acidic protein. SDS-PAGE showed three polypeptide bands, whereas two-dimensional electrophoresis revealed four spots. The peptides detected by MALDI TOF/TOF did not show sufficient homology (<30%) with the database proteins. Circular dichroism spectroscopy suggested a disordered conformational structure, and fluorescence spectrum showed the presence of tyrosine residues in the hydrophobic core. The hemagglutinating activity of ApulSL was present even after heating to 100 °C, was Mn(2+)-dependent, and inhibited by N-acetylglucosamine, D(-)-arabinose, and azocasein. ApulSL demonstrated bacteriostatic and bactericide effects on gram-positive and gram-negative species, being more effective against three varieties of Xanthomonas campestris (MIC ranging from 11.2 to 22.5 µg/mL and MBC of 22.5 µg/mL). The results of this study reinforce the importance of biochemical prospecting of Caatinga by revealing the antibacterial potential of ApulSL.


Assuntos
Antibacterianos/farmacologia , Fabaceae/química , Lectinas de Plantas/isolamento & purificação , Lectinas de Plantas/farmacologia , Sementes/química , Animais , Antibacterianos/química , Bactérias/efeitos dos fármacos , Cromatografia em Gel , Eletroforese em Gel Bidimensional , Hemaglutinação/efeitos dos fármacos , Hemaglutininas/química , Humanos , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Peptídeos/química , Lectinas de Plantas/química , Coelhos
10.
Adv Rheumatol ; 59: 52, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1088611

RESUMO

Abstract Introduction: Antiphospholipid antibodies (aPL) are described in individuals with leprosy without the clinical features of antiphospholipid antibody syndrome (APS), a condition involving thromboembolic phenomena. We have described the persistence of these antibodies for over 5 years in patients with leprosy after specific treatment. Objectives: To determine whether epidemiological, clinical and immunological factors played a role in the longterm persistence of aPL antibodies in leprosy patients after multidrug therapy (MDT) had finished. Methods: The study sample consisted of 38 patients with a diagnosis of leprosy being followed up at the Dermatology and Venereology Outpatient Department at the Alfredo da Matta Foundation (FUAM) in Manaus, AM. ELISA was used to detect anticardiolipin (aCL) and anti-β2 glycoprotein I (anti-β2GPI) antibodies. Patients were reassessed on average of 5 years after specific treatment for the disease (MDT) had been completed. Results: Persistence of aPL antibodies among the 38 leprosy patients was 84% (32/38), and all had the IgM isotype. Mean age was 48.1 ± 15.9 years, and 23 (72.0%) were male. The lepromatous form (LL) of leprosy was the most common (n = 16, 50%). Reactional episodes were observed in three patients (9.4%). Eighteen (47.37%) were still taking medication (prednisone and/or thalidomide). Mean IgM levels were 64 U/mL for aCL and 62 U/mL for anti-β2GPI. In the multivariate binary logistic regression the following variables showed a significant association: age (p = 0.045, OR = 0.91 and CI 95% 0.82-0.98), LL clinical presention (p = 0.034; OR = 0.02 and CI 95% = 0.0-0.76) and bacterial index (p = 0.044; OR = 2.74 and CI 95% = 1.03-7.33). We did not find association between prednisone or thalidomide doses and positivity for aPL (p = 0.504 and p = 0.670, respectively). No differences in the variables vascular thrombosis, pregnancy morbidity, diabetes, smoking and alcoholism were found between aPL-positive and aPL-negative patients. Conclusion: Persistence of positivity for aPL antibodies was influenced by age, clinical presentation and bacterial index. However, further studies are needed to elucidate the reason for this persistence, the role played by aPL antibodies in the disease and the B cell lineages responsible for generation of these antibodies.


Assuntos
Humanos , Hanseníase/patologia , Ensaio de Imunoadsorção Enzimática/instrumentação , Anticorpos Antifosfolipídeos/análise , Anticorpos Anticardiolipina/análise , Quimioterapia Combinada/efeitos adversos , beta 2-Glicoproteína I/análise
11.
Nat Prod Res ; 28(16): 1297-301, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24670137

RESUMO

Although it is one of the most threatened areas in the Earth, there are few studies on the biotechnological potential of the Caatinga. This work evaluated 36 extracts from 27 Caatinga plants for lectin and trypsin inhibitor activities. The presence of lectin was detected in 77.7% of samples by haemagglutinating assay. The highest values of specific haemagglutinating activity were found in extracts of leaves from Mimosa lewesii, Bauhinia acuruana and Manilkara rufula and in branches from Myracrodruon urundeuva. Trypsin inhibitor activity was detected in 63.9% of the tested extracts, strong inhibitory effect (>70%) being found in 11 samples. This work demonstrates that Caatinga is a potential source of bioactive plant proteins that can be isolated and studied for several applications. The biochemical prospecting of Caatinga is essential for collection of bioactive principles so as to add conservation value to the region.


Assuntos
Lectinas/isolamento & purificação , Lectinas/farmacologia , Plantas Medicinais/química , Inibidores da Tripsina/isolamento & purificação , Inibidores da Tripsina/farmacologia , Bauhinia/química , Lectinas/química , Manilkara/química , Medicina Tradicional , Mimosa/química , Estrutura Molecular , Extratos Vegetais/farmacologia , Folhas de Planta , Inibidores da Tripsina/química
12.
Plant Sci ; 183: 20-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22195573

RESUMO

Hemagglutinating activity has been associated to presence of lectin, carbohydrate-binding proteins. In this work Crataeva tapia bark lectin (CrataBL) was purified in milligram quantities (28 mg per g of bark) by ion exchange chromatography. The lectin was thermo-stable, ion-independent and N-terminal sequence analysis demonstrated similarity with miraculin and miraculin-like proteins (plant defensive proteins). Glycosylated nature of CrataBL was revealed using glycoprotein staining (periodic acid-Schiff's reagent), positive for polypeptides of apparent molecular masses 21 and 40 kDa on SDS-PAGE. Gel diffusion assay showed that glucose/mannose isolectins from Cratylia mollis recognized CrataBL glycan moiety. CrataBL hemagglutinating activity was inhibited by glycoproteins and CrataBL immobilized on cyanogen bromide-activated sepharose 4B (1 mL) bound 0.54 mg of glycoprotein (casein, fetuin and ovalbumin) per cycle. CrataBL was an insecticide agent against Nasutitermes corniger workers (termite that attack woods) with LC50 of 0.475 mg mL⁻¹ for 6 days.


Assuntos
Capparaceae/química , Inseticidas/química , Casca de Planta/química , Extratos Vegetais/química , Lectinas de Plantas/química , Animais , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Hemaglutinação , Inseticidas/isolamento & purificação , Isópteros , Extratos Vegetais/isolamento & purificação , Lectinas de Plantas/isolamento & purificação
14.
Braz. j. microbiol ; 33(4): 347-351, Oct.-Dec. 2002. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-342099

RESUMO

Protoplasts of the wild type Streptomyces clavuligerus NRRL 3585 (ATCC 27064) were formed from spores cultures obtained in the lag, exponential and stationary growth phases by using 0.5 percent glycine in the culture medium. The protoplasts were obtained by treatment of the cells with lysozyme (Ec û3.2.1.17) 40,000 U (1mg/ml), in an osmotic solution for 90 min at 28oC. The frequency of regenerated protoplasts in the lag phase was 1.7x103 CFU/ml (28,97 percent), in the beginning of the exponential phase 0.4x102 CFU/ml (31.67 percent), in the exponential growth phase 2.5x103 CFU/ml (46.30 percent) and 1.0x105 CFU/ml in stationary phase (48.45 percent). Antibiotic production and activity of regenerated protoplasts were observed in all phases, except in the lag phase. The protoplast formation and regeneration techniques resulted in a new isolate strain of Streptomyces clavuligerus that produced approximately 2.5 fold more clavulanic acid.


Assuntos
Ácido Clavulânico/análise , Ácido Clavulânico/isolamento & purificação , Técnicas In Vitro , Protoplastos , Streptomyces , Meios de Cultura , Métodos
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