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Recent Discoveries of Natural Products as Antimicrobial Alternatives for Bovine Mastitis Treatment
Published in Mahendra Rai, Chistiane M. Feitosa, Eco-Friendly Biobased Products Used in Microbial Diseases, 2022
Pâmella B. A. Domingues, João Paulo L. Morgado, Maria Aparecida S. Moreira, Valdir F. Veiga-Júnior, Fábio A. Pieri
St. John’s wort, Hypericum perforatum L., has therapeutic effects reported in literature on burns, bruises, swelling, anxiety and depression, in addition to antiviral, wound healing, analgesic, hepatoprotective, antioxidant and antimicrobial activities. The effects occur by the presence of compounds such as naftodiantrons, flavonol glycosides, biflavones, proanthocyanidins and phenylpropans (Okmen and Balpınar 2017). The antioxidant activity of the methanolic extract obtained from the flowers of H. perforatum was evaluated by Okmen and Balpınar (2017) using the DPPH test. The authors observed that 32% inhibition of free radicals was obtained with the extract at a concentration of 100 mg/mL, equivalent to 0.83 mM/g of Trolox, the control used in the study. Comparing the results of the DPPH tests carried out with methanolic extracts of M. oleifera leaves and flowers of H. perforatum L., the Moringa extract appears to have better antioxidant activities, as it eliminates a higher percentage of free radicals at a lower concentration (Okmen and Balpınar 2017).
Aquatic Plants Native to Asia and Australia
Published in Namrita Lall, Aquatic Plants, 2020
Marco Nuno De Canha, Danielle Twilley, B. Venugopal Reddy, SubbaRao V. Madhunapantula, N. P. Deepika, T. N. Shilpa, B. Duraiswamy, S. P. Dhanabal, Suresh M. Kumar, Namrita Lall
The aqueous and ethanolic extracts of B. monnieri showed 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity with IC50 values of 76.42 and 469 µg/ml, respectively. The aqueous and ethanolic extracts reduced lipid peroxidation by 79.02% and 95.78%, respectively, when tested at a concentration of 1 mg/ml (Mukherjee et al. 2011). The methanol extract of B. monnieri, which has been reported for its superoxide scavenging activity with 25 µg/ml, show similar effects to 80 mU/ml of inherent human superoxide dismutase (SOD) activity. At a concentration of 400 µg/ml using the DPPH free radical scavenging assay, the extract was comparable in activity equivalent to 30 µM Trolox. The extract also showed protective activity on human fibroblast cells treated with hydrogen peroxide where cell viability was increased from 42.75% to 62.75% and 82.41% at 12 and 25 µg/ml, respectively (Russo et al. 2003).
The Use of Brain Slices in the Study of Free Radical Actions
Published in Avital Schurr, Benjamin M. Rigor, BRAIN SLICES in BASIC and CLINICAL RESEARCH, 2020
The protective properties of antioxidants and free radical scavengers add further support for a free radical mechanism underlying the actions of the generating systems used in the hippocampal slice. Dimethyl sulfoxide (DMSO) is a hydroxyl radical scavenger.43–45 It protects E/S coupling against impairment by peroxide and by dihydroxyfumarate.26,38 However, it does not protect against the decreased synaptic efficacy occurring with peroxide exposure.26 The hydroxyl radical scavenger, thiourea, is an effective protectant in many systems.3 Unfortunately, it has direct actions on electrophysiological potentials in the hippocampal slice preparation, making interpretation of the data difficult. However, it does appear to limit the damage produced by peroxide when the concentration is carefully chosen.26 Trolox C, a water-soluble vitamin E analog, is an antioxidant that protects tissue in part by scavenging peroxy radicals.3,46–48 Trolox C is very effective in hippocampal slices, limiting the consequences of exposure to hydrogen peroxide26 (Figure 2).
Chitooligosaccharide-catechin conjugate loaded liposome using different stabilising agents: characteristics, stability, and bioactivities
Published in Journal of Microencapsulation, 2023
Ajay Mittal, Avtar Singh, Hui Hong, Soottawat Benjakul
For ORAC, 20 µL of samples were loaded onto a black polystyrene 96-wells microplate. The loaded microplate was inserted into a FLUOstar Omega microplate reader (BMG Labtechnologies GmbH, Offenberg, Germany) equipped with FLUOstar Omega evaluation software version 5.10. The samples were equilibrated at 37 °C for 10 min. Thereafter, 200 µL of 0.11 µM fluorescein dissolved in 75 mM phosphate buffer (pH 7.0) was added to the sample. The reaction was started by the addition of 75 µL of 60 mM 2,2-azobis(2-amidino-propane) dihydrochloride (AAPH) and performed at 37 °C. The fluorescence intensity was measured every 2 min for 75 cycles with excitation and emission filters of 485 and 520 nm, respectively. The blank was prepared in the same manner, except that 75 mM phosphate buffer (pH 7.0) was used instead of the sample. The kinetic curve (AUC) of all samples was plotted between fluorescence intensity and the number of cycles. Control was also prepared in the same manner except that the sample was omitted and distilled water was used instead. Trolox at a concentration of 0.08 mg/mL was used as the reference.
Flaxseed extract reduces tissue accumulation and enhances urinary excretion of chondroitin sulphate in the rat: a possible new path in substrate reduction therapy for mucopolysaccharidosis
Published in Pharmaceutical Biology, 2022
Sabir Es-said, Karima Lafhal, Abdelaati Elkhiat, Miloud Hammoud, Noureddine Regbaoui, Aicha Ezoubeiri, Rachida Makbal, Safia Sbyea, Omar Elhiba, Souad Sellami, Hanane Rais, Abdallah Karim, Halima Gamrani, Noureddine Rada, Mohammed Bouskraoui, Naima Fdil
Free radical scavenging activity of plant samples was determined by ABTS radical cation decolonization assay (Re et al. 1999). ABTS+ cation radical was produced by the reaction between 7 mM ABTS in water and 2.45 mM potassium persulfate (1:1) and stored in the dark at room temperature for 12–16 h before use. ABTS+ solution was then diluted with methanol to obtain an absorbance of 0.700 at 734 nm. After the addition of 5 μL of plant extract to 3.995 mL of diluted ABTS+ solution, the absorbance was measured at 30 min after the initial mixing. An appropriate solvent blank was run in each assay. All the measurements were carried out at least three times. Inhibition of absorbance at 734 nm was calculated using the formula: ABTS+ scavenging effect (%) = ((AB–AA)/AB) ×100 (2), where AB is absorbance of ABTS radical + methanol, AA is absorbance of ABTS radical + sample extract/standard. Trolox was used as standard substance.
The Anticancer Effect of Inula viscosa Methanol Extract by miRNAs’ Re-regulation: An in vitro Study on Human Malignant Melanoma Cells
Published in Nutrition and Cancer, 2022
Dilara Kamer Colak, Unal Egeli, Isil Ezgi Eryilmaz, Onder Aybastier, Hulusi Malyer, Gulsah Cecener, Berrin Tunca
Antioxidant activity of IVM and IVW was carried out by OA. Trolox was used as the standard substance in antioxidant capacity determination. Trolox solutions of different concentrations were prepared to create a calibration graph. A 6 mM ABTS stock solution in ethanol was prepared and used by diluting 1:10 with distilled water for analysis. 3.9 ml of ethanol was added to 0.1 ml of sample/standard for analysis. 1 ml of diluted ABTS solution was added, and the absorbance was measured at 734 nm after waiting for 6 min. The %inhibition value of each sample was calculated based on the absorbance of the antioxidant free sample. The % inhibition graph was plotted against the amount of Trolox, and the correct equation was calculated by the least-squares method. The antioxidant capacity amounts for the samples were calculated using the determined calibration equation.