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1.
J Sci Food Agric ; 102(2): 794-800, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34223648

RESUMO

BACKGROUND: Two edible coating (EC) emulsions based on potato starch (F6 and F10) alone or formulated with sodium benzoate (SB, 2% w/w) (F6/SB and F10/SB) were evaluated to maintain postharvest quality of cold-stored 'Fino' lemons and control sour rot on lemons artificially inoculated with Geotrichum citri-aurantii. Previous research showed the potential of these ECs to improve the storability of 'Orri' mandarins and reduce citrus green and blue molds caused by Penicillum digitatum and Penicillium italicum, respectively. RESULTS: The coatings F6/SB and F10/SB significantly reduced sour rot incidence and severity compared to uncoated control samples on lemons incubated at 28 °C for 4 and 7 days. The F6/SB coating reduced weight loss and gas exchange compared to uncoated fruit after 2 and 4 weeks of storage at 12 °C plus a shelf life of 1 week at 20 °C, without adversely affecting the lemon physicochemical quality. CONCLUSION: Overall, the F6/SB coating formulation, composed of pregelatinized potato starch, glyceryl monostearate, glycerol, emulsifiers and SB, with a total solid content of 5.5%, showed the best results in reducing citrus sour rot and maintaining the postharvest quality of cold-stored 'Fino' lemons. Therefore, it showed potential as a new cost-effective postharvest treatment suitable to be included in integrated disease management programs for citrus international markets with zero tolerance to chemical residues. © 2021 Society of Chemical Industry.


Assuntos
Citrus/microbiologia , Conservação de Alimentos/métodos , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Geotrichum/efeitos dos fármacos , Doenças das Plantas/microbiologia , Amido/química , Amido/farmacologia , Citrus/química , Composição de Medicamentos , Armazenamento de Alimentos , Frutas/química , Frutas/microbiologia , Geotrichum/crescimento & desenvolvimento , Doenças das Plantas/prevenção & controle , Benzoato de Sódio/química , Solanum tuberosum/química
2.
Chembiochem ; 22(10): 1823-1832, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33527702

RESUMO

Accessing aldehydes from carboxylate moieties is often a challenging task. In this regard, carboxylate reductases (CARs) are promising catalysts provided by nature that are able to accomplish this task in just one step, avoiding over-reduction to the alcohol product. However, the heterologous expression of CARs can be quite difficult due to the excessive formation of insoluble protein, thus hindering further characterization and application of the enzyme. Here, the heterologous production of the carboxylate reductase from Nocardia otitidiscaviarum (NoCAR) was optimized by a combination of i) optimized cultivation conditions, ii) post-translational modification with a phosphopantetheinyl transferase and iii) selection of an appropriate expression strain. Especially, the selection of Escherichia coli tuner cells as host had a strong effect on the final 110-fold increase in the specific activity of NoCAR. This highly active NoCAR was used to reduce sodium benzoate to benzaldehyde, and it was successfully assembled with an in vitro regeneration of ATP and NADPH, being capable of reducing about 30 mM sodium benzoate with high selectivity in only 2 h of reaction.


Assuntos
Aldeído Oxirredutases/metabolismo , Proteínas de Bactérias/metabolismo , Nocardia/enzimologia , Aldeído Oxirredutases/genética , Proteínas de Bactérias/genética , Escherichia coli/metabolismo , NADP/metabolismo , Oxirredução , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Benzoato de Sódio/química , Benzoato de Sódio/metabolismo , Solubilidade
3.
Molecules ; 26(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200707

RESUMO

Concentrated liquid coffees (CLCs) refer to stored extracts stable at environmental temperature, used as ingredients in the retail market. Their low chemical stability affects the sensory profile. This study was performed in two CLCs, one without additives (BIB) and another with a mix of sodium benzoate and potassium sorbate additives (SD), stored at 25 °C for one year. Quantitative-Descriptive (QDA) and discriminant analyses permitted identifying the critical sensory attributes and their evolution over time. The concentrate without additives presented an acceptance limit of 196 days (evaluated at a 50% acceptance ratio), while the additives increased the shelf life up to 226 days (38.9% improvement). The rejection was related to a decreased aroma, increased acidity, and reduced bitterness. A bootstrapped feature selection version of Partial Least Square analysis further demonstrated that reactions of 5-caffeoylquinic acid (5CQA) and 3,5-dicaffeoylquinic acid (3,5diCQA) could cause changes in the aroma at the first degradation stage. In the following stages, changes in fructose and stearic acid contents, a key indicator of acceptance for both extracts possibly related to non-enzymatic reactions involving fructose and other compounds, might affect the bitterness and acidity. These results provided valuable information to understand flavor degradation in CLCs.


Assuntos
Café/química , Aromatizantes/química , Frutose/química , Análise dos Mínimos Quadrados , Odorantes , Benzoato de Sódio/química , Ácido Sórbico/química , Ácidos Esteáricos/química , Paladar/efeitos dos fármacos , Temperatura
4.
Ann Pharm Fr ; 77(5): 394-417, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31257019

RESUMO

Voriconazole is a second-generation triazole derived from fluconazole, having an enhanced antifungal spectrum, compared with older triazoles. It is the drug of choice for treatment of invasive aspergillosis and many Scedosporium/Pseudallescheria Fusarium infections. Voriconazole is available in both intravenous and oral formulations. Since there is much interest in pharmaceutical quality control, separation of impurities from the main drug substances and accurate assay quantification, and since there is no reference or monograph until nowadays reported for the simultaneous separation of voriconazole from its specified and unspecified impurities along with sodium benzoate used as an antimicrobial preservative, our aim of this work is to develop a new simple, sensitive and stability indicating assay method allowing thus separation by high-performance liquid chromatography. The development of our method consisted in optimizing the following analytical parameters: nature and composition of the mobile phase, its pH, buffer concentration, nature of the stationary phase, column temperature and detection wavelength. After optimisation, separation was achieved on a stainless steel column NOVAPACK C18 (3.9mm×150mm; 4µm particle size) using a gradient mode with methanol, acetonitrile R and an aqueous solution acidified by acetic acid at 1% and adjusted to pH 2.77. The eluted compounds were monitored at 254nm. The flow rate was set at 1.0mL/min, the injection volume at 10µL, and the column oven temperature was maintained at 35°C. Under these conditions, separation was achieved with good resolution and symmetrical peaks' shape. The developed method was validated according to the International Conference on Harmonization (ICH) guidelines, and then it was successfully applied to establish inherent stability of the pharmaceutical formulation subjected to different ICH prescribed stress conditions. The developed method was proved to be simple, specific and precise. Hence, it can be considered as a method for stability study and for routine quality control analysis of voriconazole and sodium benzoate in a powder for oral suspension.


Assuntos
Antifúngicos/isolamento & purificação , Conservantes Farmacêuticos/química , Benzoato de Sódio/química , Voriconazol/isolamento & purificação , Administração Oral , Antifúngicos/química , Cromatografia Líquida de Alta Pressão , Contaminação de Medicamentos , Estabilidade de Medicamentos , Limite de Detecção , Pós , Controle de Qualidade , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Suspensões , Voriconazol/química
5.
Neurochem Res ; 42(11): 3279-3288, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28780732

RESUMO

Irregular N-methyl-D-aspartate receptor (NMDAR) function is one of the main hypotheses employed to facilitate understanding of the underlying disease state of schizophrenia. Although direct agonism of the NMDAR has not yielded promising therapeutics, advances have been made by modulating the NMDAR co-agonist site which is activated by glycine and D-serine. One approach to activate the co-agonist site is to increase synaptic D-serine levels through inhibition of D-amino acid oxidase (DAO), the major catabolic clearance pathway for this and other D-amino acids. A number of DAO inhibitors have been developed but most have not entered clinical trials. One exception to this is sodium benzoate which has demonstrated efficacy in small trials of schizophrenia and Alzheimer's disease. Herein we provide data on the effect of sodium benzoate and an optimised Takeda compound, PGM030756 on ex vivo DAO enzyme occupancy and cerebellar D-serine levels in mice. Both compounds achieve high levels of enzyme occupancy; although lower doses of PGM030756 (1, 3 and 10 mg/kg) were required to achieve this compared to sodium benzoate (300, 1000 mg/kg). Cerebellar D-serine levels were increased by both agents with a delay of approximately 6 h after dosing before the peak effect was achieved. Our data and methods may be useful in understanding the effects of sodium benzoate that have been seen in clinical trials of schizophrenia and Alzheimer's disease and to support the potential clinical assessment of other DAO inhibitors, such as PGM030756, which demonstrate good enzyme occupancy and D-serine increases following administration of low oral doses.


Assuntos
Cerebelo/metabolismo , Clorobenzenos/farmacologia , D-Aminoácido Oxidase/antagonistas & inibidores , D-Aminoácido Oxidase/metabolismo , Inibidores Enzimáticos/farmacologia , Piridazinas/farmacologia , Serina/metabolismo , Benzoato de Sódio/farmacologia , Administração Oral , Animais , Biomarcadores/metabolismo , Clorobenzenos/administração & dosagem , Clorobenzenos/química , Cristalografia por Raios X , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Piridazinas/administração & dosagem , Piridazinas/química , Benzoato de Sódio/administração & dosagem , Benzoato de Sódio/química
6.
Pharm Dev Technol ; 21(3): 261-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25582668

RESUMO

Urea cycle disorders are a group of inherited orphan diseases leading to hyperammonemia. Current therapeutic strategy includes high doses of sodium benzoate leading to three or four oral intakes per day. As this drug is currently available in capsules or in solution, children are either unable to swallow the capsule or reluctant to take the drug due to its strong bitter taste. The objective of the present study was to develop solid, multiparticulate formulations of sodium benzoate, which are suitable for pediatric patients (i.e. flavor-masked, easy to swallow and with a dosing system). Drug layering and coating in a fluidized bed were applied for preparing sustained-release granules. Two types of inert cores (GalenIQ® and Suglets®) and three different polymers (Kollicoat®, Aquacoat® and Eudragit®) were tested in order to select the most appropriate polymer and starter core for our purpose. Physical characteristics and drug release profiles of the pellets were evaluated. A Suglets® core associated with a Kollicoat® coating seems to be the best combination for an extended release of sodium benzoate. A curing period of 8 h was necessary to complete film formation and the resulting drug release pattern was found to be dependent of the acidity of the release medium.


Assuntos
Preparações de Ação Retardada/química , Implantes de Medicamento/química , Benzoato de Sódio/química , Cápsulas/química , Química Farmacêutica/métodos , Liberação Controlada de Fármacos , Excipientes/química , Pediatria/métodos , Polímeros/química , Soluções/química
7.
Soft Matter ; 10(11): 1705-13, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24651935

RESUMO

Coacervation in an aqueous solution of cationic ammonium gemini surfactant hexamethylene-1,6-bis(dodecyldimethylammonium bromide) (C12C6C12Br2) with sodium benzoate (NaBz) has been investigated at 25 °C by turbidity titration, light microscopy, dynamic light scattering, cryogenic temperature transmission electron microscopy (Cryo-TEM), scanning electron microscopy (SEM), isothermal titration calorimetry, ζ potential and (1)H NMR measurements. There is a critical NaBz concentration of 0.10 M, only above which coacervation can take place. However, if the NaBz concentration is too large, coacervation also becomes difficult. Coacervation takes place at a very low concentration of C12C6C12Br2 and exists in a very wide concentration region of C12C6C12Br2. The phase behavior in the NaBz concentration from 0.15 to 0.50 M includes spherical micelles, threadlike micelles, coacervation, and precipitation. With increasing NaBz concentration, the phase boundaries of coacervation shift to higher C12C6C12Br2 concentration. Moreover, the C12C6C12Br2-NaBz aggregates in the coacervate are found to be close to charge neutralized. The Cryo-TEM and SEM images of the coacervate shows a layer-layer stacking structure consisting of a three-dimensional network formed by the assembly of threadlike micelles. Long, dense and almost uncharged threadlike micelles are the precursors of coacervation in the system.


Assuntos
Compostos de Amônio/química , Micelas , Água/química , Brometos/química , Calorimetria , Microscopia Eletrônica de Transmissão , Benzoato de Sódio/química
8.
Molecules ; 19(6): 8177-88, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24941341

RESUMO

Cornelian cherry (Cornus mas L.) fruits are known for their significant amounts of anthocyanins which can be used as natural food colorants. The storage stability of anthocyanins from these fruit extracts, at different temperatures (2 °C, 25 °C and 75 °C), pH 3.02, in the presence of two of the most widely employed food preserving agents (sodium benzoate and potassium sorbate) was investigated. The highest stability was exhibited by the anthocyanin extract stored at 2 °C without any added preservative, with half-life and constant rate values of 1443.8 h and 0.48 × 10(-3) h(-1), respectively. The highest value of the degradation rate constant (82.76 × 10(-3)/h) was obtained in the case of anthocyanin extract stored at 75 °C without any added preservative. Experimental results indicate that the storage degradation of anthocyanins followed first-order reaction kinetics under each of the investigated conditions. In aqueous solution, the food preservatives used were found to have a slight influence on the anthocyanins' stability.


Assuntos
Antocianinas/química , Prunus/química , Temperatura , Conservação de Alimentos , Benzoato de Sódio/química , Ácido Sórbico/química
9.
Food Chem ; 455: 139773, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38833856

RESUMO

A molecularly imprinted polymer (MIP) based microfiber differential demodulation sensing system for sodium benzoate (SB) concentration detection is proposed. The specific binding of MIP on the surface of microfibers with SB can lead to changes in local refractive index (RI). RI change induces a drift in the interference wavelength, which can be monitored by the power difference between two fiber Bragg gratings (FBGs). The sensing system can detect SB in the concentration range of 0.1-50 µg/ml, and interference wavelength and FBG power difference sensitivities are 0.55 nm/(µg/ml) and 2.64 dB/(µg/ml) in the low concentration range of 0.1-1 µg/ml, respectively, with a limit of detection (LOD) of 0.1 µg/ml. This microfiber differential demodulation sensing system is not only simple to fabricate, but also simplifies the demodulation equipment to reduce the cost, which providing a simple, reliable and low-cost technique for the quantitative detection of SB concentration in beverages and flavoured foods.


Assuntos
Polímeros Molecularmente Impressos , Benzoato de Sódio , Benzoato de Sódio/análise , Benzoato de Sódio/química , Polímeros Molecularmente Impressos/química , Fibras Ópticas , Limite de Detecção , Contaminação de Alimentos/análise , Impressão Molecular , Polímeros/química
10.
Toxicology ; 502: 153716, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38159899

RESUMO

Food additives (FAs) (flavor enhancers, sweeteners, etc.) protect foods during storage and transportation, making them attractive to consumers. Today, while the desire to access natural foods is increasing, the chemicals added to foods have started to be questioned. In this respect, genotoxicity tests have gained importance. Studies show that some food additives may have genotoxic risks. Previous studies carried out in our laboratory also revealed genotoxic effects of Monopotassium glutamate (MPG), Monosodium glutamate (MSG), Magnesium diglutamate (MDG) as flavor enhancers; Potassium benzoate (PB), Potassium sorbate (PS), Sodium benzoate (SB), Sodium sorbate (SS) as preservatives; Acesulfame potassium (ACE-K), Xylitol (XYL) as sweeteners. In this study, we determined the interactions of these food additives with ATM and p53 proteins, which are activated in the cell due to genotoxic effects, and with DNA by employing the molecular docking method for the first time. Among the food additives, SB (-4.307) for ATM, XYL (-4.629) for p53, and XYL (-4.927) for DNA showed the highest affinity. Therefore, flexible docking (IFD) scores were determined for SB, XYL, and MDG from flavor enhancers. The potential binding modes of the food additives to target molecules' possible inhibition mechanisms were determined by molecular docking. Thus, new information was obtained to show how these additives cause chromosomal abnormalities.


Assuntos
Aromatizantes , Aditivos Alimentares , Humanos , Aditivos Alimentares/toxicidade , Simulação de Acoplamento Molecular , Aromatizantes/toxicidade , Proteína Supressora de Tumor p53 , Benzoato de Sódio/análise , Benzoato de Sódio/química , Benzoato de Sódio/farmacologia , Ácido Sórbico/toxicidade , Ácido Sórbico/química , Edulcorantes , Aberrações Cromossômicas , DNA
11.
Pak J Pharm Sci ; 26(1): 159-62, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23261742

RESUMO

A novel, eco friendly, accurate, sensitive, economic and safe spectrophotometric method was developed by application of mixed hydrotropy using 2 M sodium acetate, 8 M urea, 2 M niacinamide and 2 M sodium benzoate solution (25:25:25:25% V/V) as hydrotropic agent, for the solubalizing of poorly water-soluble Furazolidone (FZ) (solubility:- 3.64e-01 mg/mL in water). There were more than 32 times enhancements in the solubility of FZ were found in mixed hydrotropic solution as compared to solubilities in distilled water. FZ shows maximum absorbance at 360 nm where sodium acetate, urea, niacinamide, sodium benzoate and other tablets excipients did not show any absorbance above 300 nm, and thus no interference in the estimation was seen. FZ was obeyed Beers law in the concentration range of 10 to 50 µg/ml (r(2)=0.9992) in mixed hydrotropic solvent with mean recovery ranging from 97.32% to 98.9%. Proposed method is new, simple, economic, safe, rapid, accurate and reproducible and was validated according to ICH guidelines and values of accuracy, precision and other statistical analysis were found to be in good accordance with the prescribed values.


Assuntos
Anti-Infecciosos/análise , Furazolidona/análise , Solventes/química , Espectrofotometria Ultravioleta , Niacinamida/química , Reprodutibilidade dos Testes , Acetato de Sódio/química , Benzoato de Sódio/química , Solubilidade , Espectrofotometria Ultravioleta/normas , Comprimidos , Ureia/química , Água/química
12.
Curr Drug Deliv ; 17(4): 333-342, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32039685

RESUMO

BACKGROUND: Hydrogels are excellent drug carriers, but their inability to retain hydrophilic drugs for a prolonged period of time has greatly limited their usage. Research has mostly focused on intricate designs and manipulations of hydrogels to expand their applications in drug delivery. OBJECTIVE: In this study, a simple approach by incorporating a hydrophobic agent, octadecyltrichlorosilane (OTS), to alginate hydrogel micro-granules (Alg-Ms), was investigated as an effective technique to prolong the release of small hydrophilic drugs. METHODS: Sodium Benzoate (SB), a highly water-soluble antimicrobial and anti-inflammatory compound, was used as a model drug. The presence of hydrophobic OTS impeded swelling of these OTS incorporated Alg-Ms (OTS-Alg-Ms), hence sustaining the release of SB. RESULT: The release data was fitted with Ritger-Peppas and Peppas-Sahlin models and the results showed that SB released from OTS-Alg-Ms with higher OTS content was mainly controlled by Fickian diffusion; with a lower OTS content, OTS-Alg-Ms swelled more easily, the combined diffusion and swelling led to a faster SB release. CONCLUSION: Thus, by simply tuning the OTS concentration in the solution where Alg-Ms were briefly submerged in a predefined release period, from hours to a few days, small hydrophilic drugs from these OTS-Alg-Ms could be successfully achieved.


Assuntos
Alginatos/química , Hidrogéis/química , Silanos/química , Benzoato de Sódio/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Propriedades de Superfície
13.
J Anim Sci ; 98(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32756961

RESUMO

We evaluated the effects of a chemical additive on the microbial communities, fermentation profile, and aerobic stability of whole-plant corn silage with or without air stress during storage. Whole-plant corn was either untreated or treated with a chemical additive containing sodium benzoate, potassium sorbate, and sodium nitrite at 2 or 3 liters/t of fresh forage weight. Ten individually treated and replicated silos (7.5 liters) were made for each treatment. Half of the silos remained sealed throughout a 63-d storage period, and the other half was subjected to air stress for 2 h/wk. The composition of the bacterial and fungal communities of fresh forage and silages untreated or treated with 2 liters/t of fresh forage weight was analyzed by Illumina Miseq sequencing. Treated silage had greater (P < 0.05) aerobic stability than untreated, even when subjected to air stress during storage, but the numbers of yeasts culturable on selective agar were not affected. However, the additive reduced the relative abundance (RA) of the lactating-assimilating yeast Candida tropicalis (P < 0.01). In air-stressed silages, untreated silage had a greater (P < 0.05) RA of Pichia kudriavzevii (also a lactate assimilator) than treated silage, whereas treated silage was dominated by Candida humilis, which is usually unable to assimilate lactate or assimilates it slowly. The additive improved the aerobic stability by specifically preventing the dominance of yeast species that can consume lactate and initiate aerobic spoilage. To the best of our knowledge, this is the first work that identifies the specific action of this additive on shifting the microbial communities in corn silage.


Assuntos
Aditivos Alimentares/farmacologia , Microbiota/efeitos dos fármacos , Benzoato de Sódio/farmacologia , Nitrito de Sódio/farmacologia , Ácido Sórbico/farmacologia , Animais , Fermentação , Aditivos Alimentares/administração & dosagem , Aditivos Alimentares/química , Silagem/análise , Benzoato de Sódio/administração & dosagem , Benzoato de Sódio/química , Nitrito de Sódio/administração & dosagem , Nitrito de Sódio/química , Ácido Sórbico/administração & dosagem , Ácido Sórbico/química , Zea mays/química
14.
Colloids Surf B Biointerfaces ; 189: 110857, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32066087

RESUMO

Hydrophobic modification PEO-PPO copolymer BP123 was synthesized, with two aromatic rings in the centre linked to PEO-PPO blocks, and the identical PEO and PPO block numbers were possessed with commercial copolymer P123. The influence of three common pharmaceutical excipient salts sodium chloride (NaCl), sodium citrate (NaCA) and sodium benzoate (NaBZ) on self-assembly behaviors of BP123 and P123 was investigated via cloud point, surface tension, pyrene fluorescence and dynamic light scattering. Solubilization for hydrophobic drug simvastatin (SV) and in vitro drug release behavior were assessed accordingly. In the presence of NaCl or NaCA, cloud point and critical micellization concentration (CMC) decreased, micelles became more hydrophobic, micellar size and drug solubilization increased, drug release rate slowed, and the impact of NaCA was more significant than NaCl. Oppositely, cloud point and CMC increased with the addition of NaBZ. NaBZ could participate in the formation of micelles by hydrophobic aromatic ring, which greatly raised solubilization of SV. Moreover, a different performance occurred when NaBZ was added to BP123 or P123, due to the hydrophobic benzene rings in BP123, which prominently enhanced the interaction with hydrophobic drug, leading to obvious delay of drug release for BP123. This work is conducive to turning copolymer property in diverse pharmaceutical applications and in drug delivery systems as drug carriers.


Assuntos
Hipolipemiantes/química , Polietilenoglicóis/química , Propilenoglicóis/química , Sinvastatina/química , Benzoato de Sódio/química , Cloreto de Sódio/química , Citrato de Sódio/química , Portadores de Fármacos/química , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Polietilenoglicóis/síntese química , Propilenoglicóis/síntese química , Solubilidade
15.
Carbohydr Polym ; 242: 116421, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32564859

RESUMO

Thermoplastic elastomer (TPE) was developed by blending thermoplastic starch (TPS) with rubber. Thermoplastic starch-chitosan (TPSC) was prepared by the solution mixing of cassava starch, chitosan (CTS) and glycerol in acidified water (lactic acid 1 wt%) at 80 °C follow by melt mixing at 130 °C. Sodium benzoate (BEN) and chlorhexidine gluconate (Cl) were added during the solution mixing as additives for antimicrobial properties. TPSC was melt-mixed with epoxidized natural rubber (ENR) (70/30 wt/wt). The tensile strength and elongation at break of the TPSC/ENR increased with the additive content. Elastic recovery was improved by the addition of Cl. A new peak in the FTIR data confirmed the reaction between the reactive functional groups of the CTS and the additives with the epoxy groups of ENR. These reactions and miscibility of the TPSC/ENR/additives blends improved the mechanical properties, elasticity, morphology, and antimicrobial properties of the blends.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antifúngicos/química , Quitosana/química , Quitosana/farmacologia , Clorexidina/análogos & derivados , Clorexidina/química , Clorexidina/farmacologia , Elastômeros/química , Elastômeros/farmacologia , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Tamanho da Partícula , Benzoato de Sódio/química , Benzoato de Sódio/farmacologia , Amido/química , Amido/farmacologia , Propriedades de Superfície , Temperatura
16.
Int J Biol Macromol ; 124: 1281-1291, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30521904

RESUMO

Thiol Protease inhibitors (cystatins) are endogenous natural inhibitors of cysteine proteases. They are present in all mammalians cells and body fluids. Cystatin are allocated into three major families. Family -I stefins, family -II cystatins and family -III kininogens, according to their amino acid sequence, molecular weight, carbohydrate content and disulphide bonds. It has been investigated that thiol proteases (cathepsin) and their endogenous inhibitor, cystatins have been closely associated with diseases like Alzheimer's, Prions, neurodegenerative diseases, cancer and diabetes. Photodynamic effect of various sensitizers' have long been applied to delineate structural and functional properties of biologically active proteins. Flavins are well known to photo oxidize amino acids which effects conformation of proteins. Riboflavin (Vit B2) with a recommended daily requirement of approximately 2-3 mg is a yellow pigment, It is widely distributed in human tissues and blood, in both free and conjugated forms. In the present Study it has been shown that cystatin purified from buffalo brain (BC) is susceptible to reactive oxygen species generated by photo activation of riboflavin. It was observed that Photo activated riboflavin leads to inactivation of BC. Major Loss of tryptophan intensity was observed in the presence of purified thiol protease inhibitor upon incubation with 50 µM of riboflavin. In order to inspect the type of reactive oxygen species involved in inactivation of the inhibitor, different scavenger's were used namely glucose, potassium Iodide, sodium azide, manitol, thiourea, sodium benzoate, curcumin, quercetin, ascorbic acid and uric acid. It was found that Glucose, Potassium Iodide and sodium azide, have preventive effect on photo inactivation of the purified cystatin whilst other scavengers illustrated diminutive defensive effect.


Assuntos
Cistatinas/química , Sequestradores de Radicais Livres/química , Radicais Livres/antagonistas & inibidores , Riboflavina/química , Animais , Ácido Ascórbico/química , Química Encefálica , Búfalos , Curcumina/química , Radicais Livres/química , Glucose/química , Cinética , Luz , Manitol/química , Oxirredução , Processos Fotoquímicos , Iodeto de Potássio/química , Quercetina/química , Riboflavina/efeitos da radiação , Azida Sódica/química , Benzoato de Sódio/química , Tioureia/química , Ácido Úrico/química
17.
Food Chem ; 293: 491-498, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151640

RESUMO

Synthetic food preservatives like sodium acetate (SA), sodium benzoate (SB), potassium sorbate (PS) and Butyl paraben (BP) have been widely used in food and pharmacy industries. One of the toxicological aspects of food additives is evaluation of their interaction with serum proteins such as albumin. These additives interaction with human serum albumin (HSA) can exert considerable effect on the absorption, distribution, metabolism and toxicity of chemical compounds. It should be noticed that the aforementioned food preservatives intake increase mainly in the presence of glucose may lead to complex formation of SA, SB, PS and BP with HSA and accelerate the development of variety disease such as cancer, diabetes, multiple sclerosis, brain damage, nausea and cardiac disease. Therefore, to understand the mechanisms of aforementioned food additives interaction and conformational changes of proteins, we aim to review various studies that investigated albumin interaction with these additives using several procedures.


Assuntos
Conservantes de Alimentos/química , Albumina Sérica/química , Citocinas/genética , Citocinas/metabolismo , Dano ao DNA/efeitos dos fármacos , Conservantes de Alimentos/toxicidade , Humanos , Estresse Oxidativo/efeitos dos fármacos , Parabenos/química , Parabenos/toxicidade , Acetato de Sódio/química , Acetato de Sódio/toxicidade , Benzoato de Sódio/química , Benzoato de Sódio/toxicidade , Ácido Sórbico/química , Ácido Sórbico/toxicidade
18.
Int J Pharm Compd ; 22(4): 326-328, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30021187

RESUMO

The stability of extemporaneously prepared sodium benzoate oral suspension in cherry syrup and Ora-Sweet was studied. Oral solutions of 250-mg/mL sodium benzoate were prepared in either cherry syrup or Ora-Sweet. To a beaker, 50 grams of Sodium Benzoate Powder USP was dissolved and filtered, the solution was divided equally into two parts, and each aliquot was added into two separate calibrated 100-mL amber vials. In the first vial, cherry syrup was added to make a final volume of 100 mL. In the second vial, Ora-Sweet was added to give a final volume of 100 mL. This process was repeated to prepare three solutions of each kind and all were stored at room temperature. A 250-µL sample was withdrawn immediately after preparation and again at 7, 14, 28, 60, and 90 days for each sample. At each time point, further dilution was made to an expected concentration of 0.25 mg/mL with sample diluent, and the samples were assayed in triplicate by stability-indicating high-performance liquid chromatography. Stability was defined as the retention of at least 90% of the initial concentration. At least 92% of the initial concentration of sodium benzoate in cherry syrup and at least 96% of the sodium benzoate in Ora-Sweet remained throughout the 90-day study period. There were no detectable changes in color and no visible microbial growth in any sample. Extemporaneously compounded suspensions of sodium benzoate in cherry syrup or Ora-Sweet were stable for at least 90 days when stored in a 4-oz amber plastic bottle at room temperature in reduced lighting.


Assuntos
Benzoato de Sódio/química , Administração Oral , Estabilidade de Medicamentos , Suspensões
19.
J Environ Sci (China) ; 19(4): 438-43, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17915707

RESUMO

Information on the binding of organic ligands to metal (hydr)oxide surfaces is useful for understanding the adsorption behaviour of natural organic matter on metal (hydr)oxide. In this study, benzoate and salicylate were employed as the model organic ligands and aluminum hydroxide as the metal hydroxide. The attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra revealed that the ligands benzoate and salicylate do coordinate directly with the surface of hydrous aluminum hydroxide, thereby forming inner-sphere surface complexes. It is concluded that when the initial pH is acidic or neutral, monodentate and bridging complexes are to be formed between benzoate and aluminum hydroxide while bridging complexes predominate when the initial pH is alkalic. Monodentate and bridging complexes can be formed at pH 5 while precipitate and bridging complexes are formed at pH 7 when salicylate anions are adsorbed on aluminum hydroxide. The X-ray photoelectron (XP) spectra demonstrated the variation of C 1s binding energy in the salicyate and phenolic groups before and after adsorption. It implied that the benzoate ligands are adsorbed through the complexation between carboxylate moieties and the aluminum hydroxide surface, while both carboxylate group and phenolic group are involved in the complexation reaction when salicylate is adsorbed onto aluminum hydroxide. The information offered by the XPS confirmed the findings obtained with ATR-FTIR.


Assuntos
Hidróxido de Alumínio/química , Benzoato de Sódio/química , Salicilato de Sódio/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier
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