RESUMO
This study employs electrochemical and Density Functional Theory (DFT) calculation approaches to investigate the potential of a novel analogue of trimetozine (TMZ) antioxidant profile. The correlation between oxidative stress and psychological disorders indicates that antioxidants may be an effective alternative treatment option. Butylatedhydroxytoluene (BHT) is a synthetic antioxidant widely used in industry. The BHT-TMZ compound derived from molecular hybridization, known as LQFM289, has shown promising results in early trials, and this study aims to elucidate its electrochemical properties to further support its potential as a therapeutic agent. The electrochemical behavior of LQFM289 was investigated using voltammetry and a mechanism for the redox process was proposed based on the compound's behavior. LQFM289 exhibits two distinct oxidation peaks: the first peak, Ep1a ≈ 0.49, corresponds to the oxidation of the phenolic fraction (BHT), and the second peak, Ep2a ≈ 1.2 V (vs. Ag/AgCl/KClsat), denotes the oxidation of the amino group from morpholine. Electroanalysis was used to identify the redox potentials of the compound, providing insight into its reactivity and stability in different environments. A redox mechanism was proposed based on the resulting peak potentials. The DFT calculation elucidates the electronic structure of LQFM289, resembling the precursors of molecular hybridization (BHT and TMZ), which may also dictate the pharmacophoric performance.
Assuntos
Antioxidantes , Morfolinas , Antioxidantes/química , Oxirredução , AnsiedadeRESUMO
Antioxidants are responsible for many beneficial health effects and are highly present in natural products, such as kombucha. Biosensors' development targeting antioxidants and phytomarkers are an active research field. This work aimed to propose a voltammetric polyphenolxidase (Cordia superba) biosensor for catechin and total phenolic compounds quantification in kombucha samples. Optimizations were performed on the biosensor of Cordia superba to improve the accuracy and selectivity, such as enzyme-substrate interaction time, analytical responses for different patterns and signal differences with the carbon paste and modified carbon paste electrode. Kombucha probiotic drink samples were fermented for 7 to 14 days at a controlled temperature (28 ± 2 °C). A linear curve was made for catechin with a range of 10.00 to 60.00 µM, with a limit of detection of 0.13 µM and limit of quantification of 0.39 µM. The biosensor proposed in this work was efficient in determining the patterns of phenolic compounds in kombucha.
Assuntos
Técnicas Biossensoriais , Catequina , Cordia , Antioxidantes , Fenóis , Carbono/químicaRESUMO
Growing concerns on free radicals are the oxidative processes associated with physiological damage. The consumption of functional foods and use of plants with antioxidant capacity are widespread. Given the importance of determining antioxidant capacity in relation to the therapeutic effect, this study was aimed at evaluating cinnamon extract (Cinnamomum sp.) in commercial samples by spectrophotometric and voltammetric methods and assessing the vascular activity of some samples. The spectrophotometric methods performed were DPPH (1,1-diphenyl-2-picrihydrazine), ABTS (2,21-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)), and Folin-Ciocalteu radical sequestration assays. For the electrochemical experiments, a three-electrode system was used, consisting of carbon paste electrode, platinum wire, and Ag/AgCl/KClsat, representing the working, auxiliary, and reference electrodes, respectively. The electroanalytical methods used were differential pulse, square wave, and cyclic voltammetries. The extracts were prepared in hydroalcoholic solution. A calibration curve with gallic acid was calculated to quantify their equivalent amounts in the analyzed extract. The correlation between the electrochemical approach and the total phenols calculated by the ABTS, DPPH, and Folin-Ciocalteu methods was 0.63, 0.7, and 0.73, respectively, with 1 being an ideal directly proportional correlation. The correlation between spectrophotometric methods was 0.83. A biosensor was developed in a carbon paste electrode using the enzyme laccase, obtained by the fungus Marasmiellus colocasiae. It was observed that the antioxidant profile of the cinnamon samples had an analytical sign improvement of up to 4 times when compared with the electrode without the modification. The samples were analyzed by mass spectrometer, and the main chemical markers found were coumarin, cinnamaldehyde, and eugenol. Pharmacological trials showed that these samples also induce a significant vasorelaxant effect associated to antioxidant potential on vascular injury induced by oxidative stress. Thus, cinnamon showed a high antioxidant capacity, in agreement with the results obtained in other studies, emphasizing its importance as a functional food.
Assuntos
Antioxidantes , Cinnamomum zeylanicum , Antioxidantes/farmacologia , Oxirredução , Fenóis , EspectrofotometriaRESUMO
BACKGROUND: Gastric ulcer has been a major cause of morbidity and mortality worldwide, and it has been linked to factors such as nutritional deficiency, smoking, stress, and continuous intake of non-steroidal antiinflammatory drugs (NSAIDs). The search for new anti-ulcer therapeutic agents has been the subject of several studies. Recently, the gastroprotective effect of Celtis iguanaea has been reported, with linoleic acid (LA) responsible for many of the therapeutic effects of this medicinal plant. AIMS: This study aims to investigate the gastroprotective activity and the possible mechanisms in which LA may be involved through different experimental assays in mice. METHODS: The gastroprotective activity of LA was evaluated in the ulcer induced by indomethacin, HCl/EtOH, hypothermic-restraint stress and pyloric ligation. For the investigation of gastroprotective mechanisms, the quantification of the volume (mL), pH and total acidity of gastric secretion were considered. RESULTS: The oral administrations of 25 mg/kg, 50 mg/kg or 100 mg/kg of body weight of LA were capable of protecting the gastric mucosa against HCl/ethanol (10 mL/kg p.o.), and oral/intraduodenal treatment administrations of 50 mg/kg LA showed protection from ulcers induced by indomethacin, hypothermic-restraint stress and pyloric ligation. CONCLUSION: The results of this study show the gastroprotective role of LA in gastric mucosal damage induced by all assayed distresses. The observed gastroprotection possibly occurs due to the mediated increase of mucosal defensive factors.