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1.
Molecules ; 29(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38611905

RESUMO

The uses of natural compounds, such as essential oils (EOs), are limited due to their instability to light, oxygen and temperature, factors that affect their application. Therefore, improving stability becomes necessary. The objective of this study was to prepare inclusion complexes of Litsea cubeba essential oil (LCEO) with ß-cyclodextrin (ß-CD) using physical mixing (PM), kneading (KN) and co-precipitation (CP) methods and to evaluate the efficiency of the complexes and their physicochemical properties using ATR-FTIR, FT-Raman, DSC and TG. The study also assessed cytotoxicity against human colorectal and cervical cancer cells and antifungal activity against Aspergillus flavus and Fusarium verticillioides. The complexation efficiency results presented significant evidence of LCEO:ß-CD inclusion complex formation, with KN (83%) and CP (73%) being the best methods used in this study. All tested LCEO:ß-CD inclusion complexes exhibited toxicity to HT-29 cells. Although the cytotoxic effect was less pronounced in HeLa tumor cells, LCEO-KN was more active against Hela than non-tumor cells. LCEO-KN and LCEO-CP inclusion complexes were efficient against both toxigenic fungi, A. flavus and F. verticillioides. Therefore, the molecular inclusion of LCEO into ß-CD was successful, as well as the preliminary biological results, evidencing that the ß-CD inclusion process may be a viable alternative to facilitate and increase future applications of this EO as therapeutic medication, food additive and natural antifungal agent.


Assuntos
Litsea , Neoplasias do Colo do Útero , Humanos , Feminino , Antifúngicos/farmacologia , Aspergillus flavus , Aditivos Alimentares
2.
J Food Sci Technol ; 60(1): 361-371, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36618036

RESUMO

The Juçara fruit (Euterpe edulis Martius) has been progressively standing out for presenting significant biological and nutritional activity. Its functional characteristics are related to its high content of anthocyanins, which, when isolated, are highly unstable, limiting their applications. The present research proposed to obtain an anthocyanin-rich extract from the juçara pulp, microencapsulate it with the maltodextrin and beta-cyclodextrin (beta-CD) matrices and evaluate the stability of the microencapsulated anthocyanins against light, pH, and milk development fermented. The use of encapsulating agents brought the anthocyanins significant thermal and light stability, in addition to intensifying their colors in a broader pH range. The FTIR-ATR techniques and the thermal analyzes of DSC and TGA showed that there was no molecular inclusion between the anthocyanins in the extract and beta-CD, but there was a physical interaction with the maltodextrin. In the development of fermented milk, the use of maltodextrin showed better product color stability. Therefore, anthocyanin microencapsulation processes can contribute to the development of innovative, more stable, and effective commercial food products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05623-w.

3.
Bioprocess Biosyst Eng ; 42(4): 621-629, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30604010

RESUMO

Bacillusfirmus strain 37 produces the cyclomaltodextrin glucanotransferase (CGTase) enzyme and CGTase produces cyclodextrins (CDs) through a starch cyclization reaction. The strategy for the cloning and expression of recombinant CGTase is a potentially viable alternative for the economically viable production of CGTase for use in industrial processes. The present study used Bacillus subtilis WB800 as a bacterial expression host for the production of recombinant CGTase cloned from the CGTase gene of B. firmus strain 37. The CGTase gene was cloned in TOPO-TA® plasmid, which was transformed in Escherichia coli DH5α. The subcloning was carried out with pWB980 plasmid and transformation in B. subtilis WB800. The 2xYT medium was the most suitable for the production of recombinant CGTase. The enzymatic activity of the crude extract of the recombinant CGTase of B. subtilis WB800 was 1.33 µmol ß-CD/min/mL, or 7.4 times greater than the enzymatic activity of the crude extract of CGTase obtained from the wild strain. Following purification, the recombinant CGTase exhibited an enzymatic activity of 157.78 µmol ß-CD/min/mL, while the activity of the CGTase from the wild strain was 9.54 µmol ß-CD/min/mL. When optimal CDs production conditions for the CGTase from B. firmus strain 37 were used, it was observed that the catalytic properties of the CGTase enzymes were equivalent. The strategy for the cloning and expression of CGTase in B. subtilis WB800 was efficient, with the production of greater quantities of CGTase than with the wild strain, offering essential data for the large-scale production of the recombinant enzyme.


Assuntos
Bacillus firmus , Bacillus subtilis , Proteínas de Bactérias , Clonagem Molecular , Glucosiltransferases , Análise de Sequência de DNA , Bacillus firmus/enzimologia , Bacillus firmus/genética , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Expressão Gênica , Glucosiltransferases/biossíntese , Glucosiltransferases/química , Glucosiltransferases/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
4.
Bioprocess Biosyst Eng ; 40(9): 1305-1316, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28567526

RESUMO

A new mathematical model was developed for the kinetics of α-, ß- and γ-cyclodextrin production, expanding an existing model that only included the production of ß- and γ-cyclodextrins, because a detailed kinetic modelling of the reactions involved allows the manipulation of the process yields. The kinetic behaviour of the commercial enzyme Toruzyme® was studied with maltodextrin as substrate at different concentrations and for CGTase from Bacillus firmus strain 37 at a concentration of 100 g L-1. The mathematical model showed a proper fit to the experimental data, within the 24-h period studied, confirming that the considered hypotheses represent the kinetic behaviour of the enzymes in the reaction medium. The kinetic parameters generated by the model allowed reproducing previous observed qualitative tendencies as it can be seen that changing experimental conditions in the reaction process such as enzyme and substrate concentrations results in large changes in the enzyme kinetics and using high substrate concentrations does not guarantee the highest conversion rates due to enzyme inhibition and reverse reactions. In addition, this new mathematical model complements previous qualitative observations enabling the manipulation of the direct and reverse reactions catalysed by the enzyme by adjusting the reaction conditions, to target quantitative results of increased productivity and better efficiency in the production of a desired cyclodextrin.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/química , Glucosiltransferases/química , Modelos Químicos , Polissacarídeos/química , Cinética
5.
J Sci Food Agric ; 96(7): 2410-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26219432

RESUMO

BACKGROUND: Agrobacterium sp. IFO 13140 cells were immobilized on a loofa sponge and used to produce curdlan over five successive cycles. The interaction between microbial cells and the loofa sponge as well as the produced curdlan were characterized by Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectrometry. The purity of the curdlan was also evaluated. The storage stability of the immobilized cells was assessed and the produced curdlan was used in a functional yogurt formulation. RESULTS: The average curdlan production by immobilized cells was 17.84 g L(-1) . The presence of the microorganism in the sponge was confirmed and did not cause alterations in the matrix, and the chemical structure of the curdlan was the same as that of commercial curdlan. The purity of both was similar. The immobilized cells remained active after 300 days of storage at -18 °C. The use of the produced curdlan in a functional yogurt resulted in a product with lower syneresis. CONCLUSION: A large number of cells physically adhered to the surface of loofa sponge fibers, and its use as an immobilization matrix to produce curdlan was effective. The use of the produced curdlan in yogurt allowed the development of a more stable product. © 2015 Society of Chemical Industry.


Assuntos
Agrobacterium/metabolismo , Manipulação de Alimentos/métodos , Luffa/química , Iogurte , beta-Glucanas/metabolismo , Agrobacterium/química , Biopolímeros , Células Imobilizadas , beta-Glucanas/química
6.
Bioprocess Biosyst Eng ; 38(6): 1055-63, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25561345

RESUMO

Cyclodextrin glycosyltransferase (CGTase) catalyzes starch conversion into cyclic or linear oligosaccharides, important industrial products for the complexation of non-polar substances. In this work, conditions to increase CGTase production from Bacillus circulans strain DF 9R were optimized by two systems. On one hand, free cells were grown in batch fermentation experiments to optimize aeration and pH. The highest activity (1.47 ± 0.21 U ml(-1)) was achieved after 48 h of growth, aeration of 1.5 vvm and pH regulated to 7.6. On the other hand, bacterial cells were immobilized on loofa and synthetic sponge, and used for CGTase production in a semi-continuous process. An initial biomass of 30 mg of lyophilized cells and an immobilization time of 24 h with loofa or synthetic sponge were enough to achieve increased production of CGTase: 0.91 ± 0.10 and 0.95 ± 0.11 U ml(-1), respectively. Sponges with immobilized bacteria were reused in 12 successive cycles. Besides, in our conditions, CGTase was not adsorbed onto the supports used for immobilization, which ensured the total recovery of the enzyme from the culture medium. The two CGTase production processes studied showed similar productivity and could be potentially scaled up.


Assuntos
Bacillus/enzimologia , Fermentação , Glucosiltransferases/biossíntese , Animais , Biomassa , Reatores Biológicos , Concentração de Íons de Hidrogênio , Poríferos
7.
Bioprocess Biosyst Eng ; 38(7): 1291-301, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25656697

RESUMO

This study aimed to improve the yield of cyclodextrins (CDs) production in repetitive batches. An innovative ultrafiltration system was used to remove the inhibitory products that accumulated in the medium and to recover the enzyme. The assays were performed with the CGTase from Bacillus firmus strain 37 in purified, semi-purified, and crude extract forms. Maltodextrin (10% w/v) and corn starch (5% w/v) were used as substrates. After eight repetitive 24-h batches, the yield of ß-CD obtained with the purified enzyme and the corn starch substrate was 0.54 mmol/L/h, which was 36% greater than that observed with the 10% maltodextrin substrate. The crude CGTase extract with the corn starch substrate showed a productivity of 0.38 mmol/L/h, which was 29% lower than using the purified enzyme and the corn starch substrate but 7% higher than using the purified enzyme and the maltodextrin substrate. The crude extract, assayed with the corn starch substrate in the presence of 10% ethanol reached 0.43 mmol/L/h productivity, which was 12% higher compared to the assay without ethanol. The semi-purified enzyme was assayed with the corn starch substrate in the presence of 10% ethanol for eight batches lasting 12 h and an excellent selectivity for the ß-CD was obtained, reaching a mean percentage of 96.0%. Therefore, this ultrafiltration system enabled several batches of CD production, with efficient removal of products inhibitory to the CGTase and recovery of the enzyme. The possibility of industrial application of this system is promising.


Assuntos
Bacillus/enzimologia , Ciclodextrinas/biossíntese , Glucosiltransferases/metabolismo , Ultrafiltração/instrumentação , Especificidade por Substrato
8.
Int J Food Sci Nutr ; 66(3): 275-81, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25666418

RESUMO

Gluten-free breads are an alternative for celiacs but are characterized by deficient sensory qualities compared with traditional breads. This work aimed to incorporate a commercial CGTase enzyme and the CGTase produced by Bacillus firmus strain 37 in the production of these breads to overcome these drawbacks. The flours employed were corn and pinion flours, which had the best CD production by CGTase, and exhibited good antioxidant activity, respectively. Rice flour was used as a control. The addition of the CGTase enzyme increased the specific volume and improved the texture of the breads. In the sensory analyses, the best score given by non-celiacs was for bread with pinion and rice flours and CGTase from B. firmus strain 37, while celiacs awarded the best score to the bread with rice flour only and same enzyme. The results demonstrate an improvement in the sensory and technological characteristics of gluten-free breads using the CGTase enzyme.


Assuntos
Pão/análise , Ciclodextrinas , Dieta Livre de Glúten , Farinha/análise , Glucosiltransferases , Traqueófitas , Zea mays , Antioxidantes/farmacologia , Bacillus/metabolismo , Doença Celíaca/dietoterapia , Ciclodextrinas/metabolismo , Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Glucosiltransferases/metabolismo , Glutens/efeitos adversos , Humanos , Oryza , Sementes , Paladar
9.
Molecules ; 20(5): 7957-73, 2015 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-25946555

RESUMO

Curdlan production by Agrobacterium sp. IFO13140 immobilized on loofa sponge, alginate and loofa sponge with alginate was investigated. There was no statistically-significant difference in curdlan production when the microorganism was immobilized in different matrices. The loofa sponge was chosen because of its practical application and economy and because it provides a high stability through its continued use. The best conditions for immobilization on loofa sponge were 50 mg of cell, 200 rpm and 72 h of incubation, which provided a curdlan production 1.50-times higher than that obtained by free cells. The higher volumetric productivity was achieved by immobilized cells (0.09 g/L/h) at 150 rpm. The operating stability was evaluated, and until the fourth cycle, immobilized cells retained 87.40% of the production of the first cycle. The immobilized cells remained active after 300 days of storage at 4 °C. The results of this study demonstrate success in immobilizing cells for curdlan biosynthesis, making the process potentially suitable for industrial scale-up. Additional studies may show a possible contribution to the reduction of operating costs.


Assuntos
Agrobacterium/metabolismo , Células Imobilizadas/metabolismo , Luffa/metabolismo , Luffa/microbiologia , Poríferos/metabolismo , beta-Glucanas/metabolismo , Animais , Temperatura
10.
Food Technol Biotechnol ; 53(4): 385-396, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27904373

RESUMO

Anthocyanins extracted from the pulp of the fruit of juçara palm (Euterpe edulis Mart.) were microencapsulated with maltodextrin in order to stabilise them. Photoacoustic spectroscopy was used to investigate the photostability of the microencapsulated samples. Complementary differential scanning calorimetry and scanning electron microscopy measurements were also performed. Lyophilised extract had 14 340.2 mg/L of total anthocyanins, and the microencapsulation efficiency of 93.6%. Temperature analysis showed that maltodextrin conferred protection up to 70 °C for 120 min. Scanning electron microscopy showed that the microencapsulated particles had a flake-like morphology with a smooth surface, characteristic of lyophilisation processes. In addition, when added to yogurt, a red colourant was predominant in the samples at pH from 1.5 up to 5.0. Thermal analysis showed a weak interaction between the sample and the encapsulating agent, and photoacoustic data indicated the photostability of the matrix when exposed to light. Yogurts containing microencapsulated anthocyanins showed a more intense pink colour than yogurts treated with pure dye, and sensory analysis demonstrated that they can have good acceptance on the market. Microencapsulation enabled the innovative application of anthocyanins from juçara palm fruit, and complementary techniques allied to the photoacoustic spectroscopy were effective tools for its evaluation.

11.
World J Microbiol Biotechnol ; 30(12): 3229-44, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25267474

RESUMO

Lentinus edodes CCB-42 was immobilized in loofa sponges and applied to the biosorption of the synthetic dyes congo red, bordeaux red and methyl violet. Live immobilized microorganisms achieved average decolorations of congo red, bordeaux red and methyl violet of 97.8, 99.7 and 90.6 %, respectively. The loofa sponge was the support and the coadjuvant promoting dye adsorption. The biosorption conditions were optimized for each dye, yielding 30 °C, pH 5.0 and a 12 h reaction time for congo red; 25 °C, pH 3.0 and 36 h for bordeaux red; and 25 °C, pH 8.0 and 24 h for methyl violet. Operational stability was evaluated over five consecutive cycles, with both bordeaux red and congo red exhibiting decolorations above 90 %, while the decoloration of methyl violet decreased after the third cycle. In the sixth month of storage, congo red, bordeaux red and methyl violet had decolorations of 93.1, 79.4 and 73.8 %, respectively. Biosorption process best fit the pseudo-second-order kinetic and Freundlich isotherm models. Maximum biosorption capacity of heat-treated L. edodes immobilized in loofa sponge was determined as 143.678, 500.00 and 381.679 mg/g for congo red, bordeaux red and methyl violet, respectively. Treatment with immobilized L. edodes reduced the phytotoxicity of the medium containing dyes. FT-Raman experiments suggested the occurrence of interactions between loofa sponge fibers, L. edodes and dye. L. edodes CCB-42 immobilized in loofa sponges represents a promising new mode of treatment of industrial effluents.


Assuntos
Células Imobilizadas/metabolismo , Corantes/metabolismo , Luffa/microbiologia , Cogumelos Shiitake/metabolismo , Concentração de Íons de Hidrogênio , Temperatura , Fatores de Tempo
12.
Curr Drug Deliv ; 20(10): 1533-1546, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36263476

RESUMO

BACKGROUND: Nystatin (Nys) is a fungicidal drug commonly prescribed for candidiasis disease in several administration routes. However, Nys is a class IV drug, according to the Biopharmaceutical Classification System, that possesses limited bioavailability and is used for local activity. OBJECTIVE: This study developed and characterized nystatin:ß-cyclodextrin (Nys:ßCD) inclusion complexes and evaluated their activity against Candida spp. METHODS: Complexes were characterized by physicochemical techniques and drug dissolution profiles. The susceptibility of C. albicans, C. krusei, C. parapsilosis, C. glabrata, C. guilliermondii, C. tropicalis, and C. auris was assessed using the broth microdilution method. The applicability of Nys:ßCD inclusion complex was evaluated by incorporating it into a temporary soft material for denture stomatitis treatment. RESULTS: Nys was better complexed in a 1:1 molar ratio by freeze-drying and spray-drying methods. The inclusion complexes show bi-exponential release, an initial burst release followed by a sustained manner, presenting higher dissolution efficiency than raw Nys. The 1:1 freeze-drying Nys:ßCD complex presents antifungal activity against all evaluated Candida strains, showing the maintenance of the drug effectiveness. The inclusion complex incorporated into a tissue conditioner material for denture stomatitis treatment effectively inhibited more than 90% of C. albicans biofilm growth during 7 and 14 days, in a half dose compared to raw Nys. CONCLUSION: This work represents a significant contribution to treating a wide variety of diseases caused by the Candida species, optimizing the drug bioavailability and compliance to the treatment due to improved drug solubility, dissolution, and sustained delivery.


Assuntos
Antifúngicos , Estomatite sob Prótese , Antifúngicos/farmacologia , Nistatina/farmacologia , Candida , Estomatite sob Prótese/tratamento farmacológico , Estomatite sob Prótese/microbiologia , Testes de Sensibilidade Microbiana , Candida albicans , Candida parapsilosis
13.
Ther Deliv ; 14(4): 295-309, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37401351

RESUMO

Aim: This study aimed to develop, characterize and analyze the antifungal activity of chlorhexidine:ß-cyclodextrin inclusion complexes (Chx:ßCD). Materials & methods: Chx:ßCD were characterized by physicochemical techniques and the susceptibility of nine Candida strains was assessed. The inhibition of Candida albicans biofilm growth was evaluated in a denture material modified with the incorporation of Chx:ßCD. Results: Chx was better complexed in 1:2 molar ratio by freeze-drying. Chx:ßCD presented antifungal activity against all Candida strains. When incorporated into the denture material, Chx:ßCD showed better antifungal activity, as it required about 7.5% of Chx concentration compared with the raw Chx for 14 days. Conclusion: The improved characteristics of Chx:ßCD can result in new formulations to treat oral candidiasis and denture stomatitis.


Many people who wear dentures can get a fungal infection called denture stomatitis. Treating this infection is hard because it often comes back. There are many reasons why it can come back, like not following instructions, taking the wrong amount of medicine or having a bad reaction to the drugs. Using old and poorly fitting dentures and the difficulty to maintain the medicine in the right place can also make it harder to get better. One idea to make treatment easier is to add stronger drugs with fewer side effects to the material used to make dentures. That way, patients would only need to wear dentures with the right amount of medicine for a certain time to treat the infection.


Assuntos
Clorexidina , beta-Ciclodextrinas , Clorexidina/farmacologia , Antifúngicos/farmacologia , Candida albicans , beta-Ciclodextrinas/farmacologia , beta-Ciclodextrinas/química
14.
ScientificWorldJournal ; 2012: 495970, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22623901

RESUMO

While many natural and synthetic compounds exhibit auxin-like activity in bioassays, indole-3-acetic acid (IAA) is recognized as the key auxin in most plants. IAA has been implicated in almost all aspects of plant growth and development and a large array of bacteria have been reported to enhance plant growth. Cells of Klebsiella oxytoca isolated from the rhizosphere of Aspidosperma polyneuron and immobilized by adsorption on different inorganic matrices were used for IAA production. The matrices were prepared by the sol-gel method and the silica-titanium was the most suitable matrix for effective immobilization. In operational stability assays, IAA production was maintained after four cycles of production, obtaining 42.80 ± 2.03 µg mL(-1) of IAA in the third cycle, which corresponds to a 54% increase in production in relation to the first cycle, whereas free cells began losing activity after the first cycle. After 90 days of storage at 4°C the immobilized cells showed the slight reduction of IAA production without significant loss of activity.


Assuntos
Ácidos Indolacéticos/metabolismo , Klebsiella oxytoca/metabolismo , Adsorção , Biomassa , Células Imobilizadas/metabolismo , Raízes de Plantas/microbiologia , Rizosfera , Dióxido de Silício , Titânio
15.
Int J Mol Sci ; 13(10): 13294-307, 2012 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-23202953

RESUMO

This study aimed to improve the production of ß-cyclodextrin (ß-CD) by microbial cells immobilized on synthetic or loofa sponges both with and without the use of alginate or chitosan. The most suitable matrix for the immobilization of Bacillus firmus strain 7B was synthetic sponge and for Bacillus sphaericus strain 41 was loofa sponge. After 330 days of storage, the ß-CD production by Bacillus firmus and Bacillus sphaericus remained at around 41% and 49%, respectively, of initial levels. After 24 days of immobilization on loofa sponge, Bacillus sphaericus strain 41 achieved an improved operational stability, reaching 86.6 mM ß-CD after 20 days of production, compared to only 32.8 mM of ß-CD produced by free Bacillus sphaericus strain 41 cells. The expected increase in ß-CD production by immobilized cells of Bacillus firmus strain 7B on synthetic sponge for 4 days was not statistically different to that for cells immobilized for 24 days. The application of this process on an industrial scale using loofa sponge, an inexpensive and renewable matrix, will allow the stable production of ß-CD.


Assuntos
Bacillus/metabolismo , Ciclodextrinas/metabolismo , Luffa/química , Técnicas de Cultura Celular por Lotes , Células Imobilizadas/metabolismo , beta-Ciclodextrinas/metabolismo
16.
Molecules ; 17(8): 9476-88, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22874792

RESUMO

The preservation of Bacillus firmus strain 37 cells by lyophilization was evaluated and response surface methodology (RSM) was used to optimize the ß-cyclodextrin (ß-CD) production by cells immobilized on loofa sponge. Interactions were studied with the variables temperature, pH and dextrin concentration using a central composite design (CCD). Immobilization time influence on ß-CD production was also investigated. B. firmus strain 37 cells remained viable after one year of storage, showing that the lyophilization is a suitable method for preservation of the microorganism. From the three-dimensional diagrams and contour plots, the best conditions for ß-CD production were determined: temperature 60 °C, pH 8, and 18% dextrin. Considering that the amount of dextrin was high, a new assay was carried out, in which dextrin concentrations of 10, 15, and 18% were tested and the temperature of 60 °C and pH 8 were maintained. The results achieved showed very small differences and therefore, for economic reasons, the use of 10% dextrin is suggested. Increasing the immobilization time of cells immobilized on synthetic sponge the ß-CD production decreased and did not change for cells immobilized on loofa sponge. The results of this research are important for microorganism preservation and essential in the optimization of the biosynthesis of CD.


Assuntos
Bacillus/metabolismo , Frutas/química , Luffa/química , Preservação Biológica , beta-Ciclodextrinas/metabolismo , Bacillus/citologia , Aderência Bacteriana , Células Imobilizadas , Gráficos por Computador , Dextrinas/química , Liofilização , Frutas/microbiologia , Concentração de Íons de Hidrogênio , Luffa/microbiologia , Viabilidade Microbiana , Modelos Biológicos
17.
Biomolecules ; 12(3)2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35327575

RESUMO

Fish bones are a natural calcium phosphate (CaP) sources used in biomaterials production for bone regeneration. CaP scaffolds can be enriched with other substances with biological activity to improve bone repair. This study aimed to evaluate the physicochemical properties and bone regeneration potential of biphasic calcium phosphate (BCP) scaffolds impregnated with free curcumin (BCP-CL) or complexed with ß-cyclodextrin (BCP-CD) compared to BCP scaffolds. Rietveld's refinement showed that BCP is composed of 57.2% of HAp and 42.8% of ß-TCP and the molar ratio of Ca/P corresponds to 1.59. The scaffolds presented porosity (macro and microporosity) of 57.21%. Apatite formation occurred on the BCP, BCP-CL, and BCP-CD surface, in vitro, in SBF. Micro-Raman technique showed a reduction in the dissolution rate of ß-TCP in the curcumin-impregnated scaffolds over time, and in vivo studies on critical-size defects, in rat calvaria, had no additional regenerative effect of BCP-CL and BCP-CD scaffolds, compared to BCP scaffolds. Despite this, the study showed that curcumin impregnation in BCP scaffolds prolongs the release of the ß-TCP phase, the BCP- phase with the higher osteoinductive potential, representing an advantage in tissue engineering.


Assuntos
Curcumina , beta-Ciclodextrinas , Animais , Regeneração Óssea , Curcumina/farmacologia , Hidroxiapatitas , Ratos , Alicerces Teciduais/química , beta-Ciclodextrinas/farmacologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-32684097

RESUMO

There is an increasing demand for fungi control in grains, especially toxigenic. Also, there is growing concern on the use of synthetic fungicides; thus alternatives are needed. The aim of this study was to evaluate the antifungal and antimycotoxigenic action of essential oils (EOs) from Zingiber officinale, Cinnamomum zeylanicum and Cymbopogon martinii against Fusarium verticillioides, a spoilage and toxigenic fungus. Essential oils were first chemically characterised by gas chromatography coupled to mass spectrometry, and their antioxidant potential was measured by the DPPH, ABTS and FRAP methods. Minimum inhibitory concentration (MIC) and disc diffusion were used to assess antifungal activity. Scanning electron microscopy was used to evaluate morphological changes in the fungus. Antimycotoxigenic activity of the EOs against the production of fumonisin B1 and B2 by F. verticillioides was evaluated using ultra-high-performance liquid chromatography system. Z. officinale, C. zeylanicum and C. martinii EOs were predominantly composed by zingiberene and geranial; eugenol; and geraniol, respectively. All the EOs had high antioxidant power, especially that from C. zeylanicum. The MICs were 250, 500 and 2,000 µg mL-1 for C. zeylanicum, C. martinii and Z. officinale EOs, respectively. Mycelial reduction of F. verticillioides was observed when EOs were used, and the lowest activity was detected in the Z. officinale EO. Overall, the tested EOs promoted structural damage to the fungal cell wall, decreased conidia size and mycelial reduction. Antimycotoxigenic evaluation of the EOs evidenced a significant reduction (p < .05) in the production of fumonisins B1 and B2 with all the EOs evaluated in the study. These results suggest that especially C. zeylanicum and C. martinii EOs are highly useful for controlling F. verticillioides and fumonisins production.


Assuntos
Antifúngicos/farmacologia , Fumonisinas/antagonistas & inibidores , Fusarium/efeitos dos fármacos , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Cinnamomum zeylanicum/química , Cymbopogon/química , Zingiber officinale/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
19.
J Pharm Pharmacol ; 70(2): 178-190, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29072315

RESUMO

OBJECTIVES: The phytohormone methyl jasmonate (MeJA) has been identified as a vital cell regulator in plants. This substance is analogous to eicosanoids and similar to that of anti-inflammatory prostaglandins. In animals and in animal cells, it displayed an efficient neuroprotective, anti-inflammatory and antioxidant action; while in tumoral strains, it demonstrates a potentially highly attractive mechanism of apoptosis induction through various cellular and molecular mechanisms. The aim of the present review was to explore two new hypotheses that explain the action of MeJA, a lipid phytohormone and its potentially anti-apoptotic mechanism for use as a therapeutic target for future treatment of Inflammatory bowel diseases (IBDs). KEY FINDINGS: Methyl jasmonate is a new candidate for the treatment of IBDs, modulating the expression of the major classes of caspase-type protease families that selectively act on the extrinsic and intrinsic pathways of the apoptotic process. Its action is based on the reduction of the expression in tumour necrosis factor tissue levels and the modulating action of reactive oxygen species production, acting only on the destruction of cells that express the diseased phenotype, and preserving cells that are not transformed. CONCLUSIONS: Methyl jasmonate may represent an alternative for the transduction processes of important signals in the cellular renewal of the intestinal mucosa.


Assuntos
Acetatos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Ciclopentanos/uso terapêutico , Fármacos Gastrointestinais/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mucosa Intestinal/efeitos dos fármacos , Oxilipinas/uso terapêutico , Reguladores de Crescimento de Plantas , Acetatos/efeitos adversos , Animais , Anti-Inflamatórios/efeitos adversos , Apoptose/efeitos dos fármacos , Ciclopentanos/efeitos adversos , Fármacos Gastrointestinais/efeitos adversos , Humanos , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Oxilipinas/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
20.
Carbohydr Polym ; 192: 19-27, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29691012

RESUMO

The study comparatively evaluated diverse strategic models of cyclodextrin (CD) production by the CGTase of Bacillus firmus strain 37: continuous production and repetitive batches in ultrafiltration systems; immobilization of CGTase on curdlan and vegetable sponge natural supports; the use of the glycyrrhizin complexing agent to modulate CGTase selectivity in favor of γ-CD production. All strategies had in common the possibility of separation of CGTase from its inhibitory products and its reuse. In the continuous production model, at 48 h of assay, the highest productivity and selectivity for ß-CD were obtained, 1.47 mmol/L/h and 92.8%, respectively. Glycyrrhizin was able to modulate the production of γ-CD with selectivity of 61.2% for 30-h batches. The comparative evaluation of the different strategic models for obtaining CDs showed particularities that should be considered, and most of the models studied returned satisfactory yields as well as excellent selectivity.


Assuntos
Ciclodextrinas/química , Ciclodextrinas/isolamento & purificação , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Glucosiltransferases/química , Glucosiltransferases/metabolismo , Ultrafiltração/métodos , Bacillus/enzimologia , Compostos Férricos , Fosfatos , Especificidade por Substrato
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