Free Radical Scavenging Assay Research Articles

Synthesis, characterization of Schiff base metal complexes with 1, 3 propanediamine as secondary chelates and their DNA binding, DNA cleavage, cytotoxicity, antioxidant and activities

A series of Cu(II), Co(II), Ni(II), and Zn(II) complexes were synthesised from ternary Schiff base ligand (ts) and 1,3-propanediamine (pda). These complexes were characterised using analytical and spectroscopic techniques. All these metal complexes have an octahedral geometry, which is supported by spectro-analytical experimental data. The fabricated Schiff base coordinates with the metal via imine nitrogen, a phenolic oxygen atom, and carboxylate anion as a monobasic tridentate. Thermal properties were also investigated. Antimicrobial studies were carried out against fungi and pathogenic (bacterial) organisms and a good zone of inhibition was observed irrespective of complexes. Free radical scavenging assays were performed by DPPH and H2O2 methods. The results of these two studies revealed that the Cu(II) and Zn(II) complexes were more active. The binding mode of calf thymus (Ct-DNA) to the metal complexes was analysed by the electronic absorption spectroscopy and viscosity measurement study. The findings revealed that the complex bound with DNA via a groove with electrostatic interactionand the copper complex showed a higher binding constant value. Cytotoxicity of the Schiff base and its complexes were evaluated with the breast cancer (MCF-7) cell line and all complexes exhibited moderate toxicity.

Synthesis, antioxidant and anti-hypoxia activities of 6-hydroxygenistein and its methylated derivatives.

Hypoxia is a common pathological phenomenon, usually caused by insufficient oxygen supply or inability to use oxygen effectively. Hydroxylated and methoxylated flavonoids have significant anti-hypoxia activity. This study aims to explore the synthesis, antioxidant and anti-hypoxia activities of 6-hydroxygenistein (6-OHG) and its methoxylated derivatives. The 6-OHG and its methoxylated derivatives, including 4',6,7-trimethoxy-5-hydroxyisoflavone (compound 3), 4',5,6,7-tetramethoxyisoflavone (compound 4), 4',6-imethoxy-5,7-dihydroxyisoflavone (compound 6), and 4'-methoxy-5,6,7-trihydroxyisoflavone (compound 7), were synthesized by methylation, bromination, methoxylation, and demethylation using biochanin A as raw material. The structure of these products were characterized by 1hydrogen-nuclear magnetic resonance spectroscopy (1H-NMR) and mass spectrometry (MS). The purity of these compounds was detected by high pressure chromatography (HPLC). The antioxidant activity in vitro was investigated by 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) free radical scavenging assay. PC12 cells were divided into a normal group, a hypoxia model group, rutin (1×10-9-1×10-5 mol/L) groups, and target compounds (1×10-9-1×10-5 mol/L) groups under normal and hypoxic conditions. Cell viability was detected by cell counting kit-8 (CCK-8) assay, the target compounds with excellent anti-hypoxia activity and the drug concentration at the maximum anti-hypoxia activity were screened. PC12 cells were treated with the optimal concentration of the target compound or rutin with excellent anti-hypoxia activity, and the cell morphology was observed under light microscope. The apoptotic rate was determined by flow cytometry, and the expressions of hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were detected by Western blotting. The structure of 6-OHG and its 4 methylated derivatives were correct, and the purity was all more than 97%. When the concentration was 4 mmol/L, the DPPH free radical removal rates of chemical compounds 7 and 6-OHG were 81.16% and 86.94%, respectively, which were higher than those of rutin, the positive control. The removal rates of chemical compounds 3, 4, and 6 were all lower than 20%. Compared with the normal group, the cell viability of the hypoxia model group was significantly decreased (P<0.01). Compared with the hypoxia model group, compounds 3, 4, and 6 had no significant effect on cell viability under hypoxic conditions. At all experimental concentrations, the cell viability of the 6-OHG group was significantly higher than that of the hypoxia model group (all P<0.05). The cell viability of compound 7 group at 1×10-7 and 1×10-6 mol/L was significantly higher than that of the hypoxia model group (both P<0.05). The anti-hypoxia activity of 6-OHG and compound 7 was excellent, and the optimal drug concentration was 1×10-6 and 1×10-7 mol/L. After PC12 cells was treated with 6-OHG (1×10-6 mol/L) and compound 7 (1×10-7 mol/L), the cell damage was reduced, the apoptotic rate was significantly decreased (P<0.01), and the protein expression levels of HIF-1α and VEGF were significantly decreased in comparison with the hypoxia model group (both P<0.01). The optimized synthesis route can increase the yield of 6-OHG and obtain 4 derivatives by methylation and selective demethylation. 6-OHG and compound 7 have excellent antioxidant and anti-hypoxia activities, which are related to the structure of the A-ring ortho-triphenol hydroxyl group in the molecule.

Synthesis, Characterization, Molecular Docking Studies and Biological Evaluation of Thiazole Schiff Base Analogs

In this work, potentially safe few Schiff base compounds containing a thiazole moiety were synthesized and characterized. Three thiazole derivatives (2a-c) were successfully synthesized through a two-step reaction involving substituted benzaldehyde, thiosemicarbazide and 1,3-dichloroacetone. The elucidation of the synthesized compounds was accomplished by using spectral studies. Antimicrobial activities demonstrated that some compounds exhibited moderate effectiveness against microbes, compared to the standard antibiotic’s ceftriaxone and amphotericin B, using the disc diffusion technique. In the DPPH free radical scavenging assay, all compounds displayed promising antioxidant effectiveness. Moreover, the molecular docking studies showed that thiazole Schiff base analogs effectively bind to potential receptor binding sites.

Exploring antioxidative, cytotoxic and neuropharmacological insights into Bixa orellana leaves: Experimental and in silico approaches

Background StudyThe aim of this research was to examine possible antioxidant, cytotoxic and neurological activity of methanol and n-hexane extracts of Bixa orellana leaves. Additionally, we aimed to identify potential lead compounds through in-silico analysis. MethodsIn-vitro antioxidative properties were investigated through different assays, including: total phenolic content assay (TPC), total flavonoid content assay (TFC), DPPH free radical scavenging assay and reducing power assay. Also, the cytotoxic effect of the samples was assessed using the brine shrimp lethality test. In addition, anxiolytic, locomotor, and CNS depressant activities were assessed utilizing various established methods. Moreover, reported compounds were used in the in silico study to explore the best-fit phytoconstituents against gamma-aminobutyric acid (GABAA) receptor. ResultsMBOL displayed substantial antioxidative activities in various established assays compared to NBOL. In brine shrimp lethality bioassay, both MBOL and NBOL revealed cytotoxic activity in a concentration-dependent approach. Again, in Elevated Plus Maze test, 200 and 400 mg/kg of NBOL and MBOL demonstrated significant anxiolytic activities evident from time spent in open arms. In addition, maximum number of head dipping was demonstrated by MBOL at 400 mg/kg (53.90 ± 1.16) in Hole Board test. NBOL and MBOL at both doses significantly diminished the magnitude of movements from the 2nd to 5th observation periods in Open Field test. Furthermore, in Hole Cross test, MBOL remarkably dwindled the locomotor activity at 120 min and 180 min (3.60 ± 0.40 and 2.40 ± 0.51) at 400 mg/kg. Finally, in silico analysis revealed 13 compounds as promising leads with strong binding affinity to GABAA receptor along with good pharmacokinetics and toxicity profiles. ConclusionTherefore, the present study's findings advocate the traditional usage of this plant and recommend both MBOL and NBOL as as a potential source of therapeutic candidate for the management of neurological disorders.

Development of Novel Indazolyl-Acyl Hydrazones as Antioxidant and Anticancer Agents that Target VEGFR-2 in Human Breast Cancer Cells.

The increased expression of VEGFR-2 in a variety of cancer cells promotes a cascade of cellular responses that improve cell survival, growth, and proliferation. Heterocycles are common structural elements in medicinal chemistry and commercially available medications that target several biological pathways and induce cell death in cancer cells. Herein, the evaluation of indazolyl-acyl hydrazones as antioxidant and anticancer agents is reported. Compounds 4e and 4j showed inhibitory activity in free radical scavenging assays (DPPH and FRPA). The titled compounds were employed in cell viability studies using MCF-7 cells, and it was observed that compounds 4f and 4j exhibited IC50 values 15.83 μM and 5.72 μM, respectively. In silico docking revealed the favorable binding energies of -7.30 kcal/mol and -8.04 kcal/mol for these compounds towards Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2), respectively. In conclusion, compounds with antioxidant activity and that target VEGFR-2 in breast cancer cells are reported.

A Study on the Brewing of "Prot-Tea" by Blending Spirulina (Arthrospira platensis) With Green Tea.

Introduction Among different blue-green algae, Spirulina (Arthrospira platensis) is known for its high protein content and is hence considered a dietary single-cell protein. In recent decades, Spirulina has been one of the nutritive additives in food and beverage products to enhance the nutritional value of food products. The aim of this study was to brew a "Prot-Tea" enriched with antioxidants and protein for nutrition care. Materials and methods In combination, both the Spirulina and green tea were brewed together in three different formulations: formulation A: 0.5 g of Spirulina powder and 1.5 g of green tea; formulation B: 1 g each of Spirulina powder and green tea; and formulation C: 1.5 g of Spirulina powder and 0.5 g of green tea. All the formulations were brewed in 100 mL of hot water at 80°C for two minutes. Then, all the formulations were subjected to a 2,2-diphenylpicrylhydrazyl free radical scavenging assay and a quantitative protein estimation assay (Lowry method). Results Among the three different formulations, formulation B showed greater antioxidant and protein content. The antioxidant activity of formulation B was directly proportional to the concentration, with an IC50 value of 37.98 µL/mL. Similarly, the protein content was also higher in formulation B, with 287.33 µg/100 µL. The total antioxidant in formulation B was 47.61 mg of ascorbic acid equivalent. Concurrently, the total protein content was 229.86 mg in 80 mL of the total volume of Prot-Tea yield. Conclusion Based on this study, Prot-Tea is considered a future healthy beverage for nutrition care.

Zinc oxide nanoparticles functionalized with cinnamic acid for targeting dental pathogens receptor and modulating apoptotic genes in human oral epidermal carcinoma KB cells.

Oral diseases are often attributed to dental pathogens such as S. aureus, S. mutans, E. faecalis, and C. albicans. In this research work, a novel approach was employed to combat these pathogens by preparing zinc oxide nanoparticles (ZnO NPs) capped with cinnamic acid (CA) plant compounds. The synthesized ZnO-CA NPs were characterized using SEM, FTIR, and XRD to validate their composition and structural features. The antioxidant activity of ZnO-CA NPs was confirmed using DPPH and ABTS free radical scavenging assays. The antimicrobial effects of ZnO-CA NPs were validated using a zone of inhibition assay against dental pathogens. Autodock tool was used to identify the interaction of cinnamic acid with dental pathogen receptors. ZnO-CA NPs exhibited potent antioxidant activity in both DPPH and ABTS assays, suggesting their potential as powerful antioxidants. The minimal inhibitory concentration of ZnO-CA NPs against dental pathogens was found 25µg/mL, indicating their effective antimicrobial properties. Further, ZnO-CA NPs showed better binding affinity and amino acid interaction with dental pathogen receptors. Also, the ZnO-CA NPs exhibited dose-dependent (5µg/mL, 15µg/mL, 25µg/mL, and 50µg/mL) anticancer activity against Human Oral Epidermal Carcinoma KB cells. The mechanism of action of apoptotic activity of ZnO-CA NPs on the KB cells was identified through the upregulation of BCL-2, BAX, and P53 genes. This research establishes the potential utility of ZnO-CA NPs as a promising candidate for dental applications. The potent antioxidant, anticancer, and effective antimicrobial properties of ZnO-CA NPs make them a valuable option for combating dental pathogens.

Essential oils of Thymus munbyanus subsp. coloratus: chemical variability and evaluation of biological activities

The chemical compositions of Thymus munbyanus subsp. coloratus essential oils, an endemic plant in north Africa, were investigated using gas chromatography with flame ionization detection and gas chromatography-mass spectrometry. The antioxidant activity of the studied essential oils was evaluated through 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,20-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) free-radical scavenging assays. Disc diffusion method and minimal inhibitory concentration (MIC) determination were applied to investigate the antimicrobial activity of Thymus munbyanus subsp. coloratus essential oil against ten bacterial and fungus strains. Fifty-one compounds were identified accounting for 90.3-95.9% of the total amount. Camphor (04.09-25.92%) was the major component in the essential oils obtained from five localities, followed by myrcene (00.66-17.11%) in four stations, then borneol (07.37-38.96%) in the essential oil obtained from three samples. The chemical variability of Thymus munbyanus subsp. coloratus essential oils was studied using statistical analysis, in which we found a direct relationship between geo climatic conditions and their chemical compositions. Thymus munbyanus subsp. coloratus essential oils exhibited a good radical-scavenging activity with IC50 values up to 0.250 ± 0.51 and 0.596 ± 0.15 (mg/mL) in reductive potential of ABTS and DPPH free radicals, respectively, and a significant antimicrobial activity against Gram positive bacteria and fungal species with MIC up to 0.66 ± 0.28 (mg/mL) against Aspergillus flavus.

Measurement of antioxidant synergy between phenolic bioactives in traditional food combinations (legume/non-legume/fruit) of (semi) arid regions: insights into the development of sustainable functional foods

Numerous under-researched edible plants are present in the desert regions of the world. These plants could be potential candidates to ensure food security and provide valuable bioactive compounds through diet. In general, the bioactives present in food manifest synergistic, additive, or antagonistic interactions. The current study investigates such interactions between food combinations traditionally consumed in (semi) arid regions. Five edible plants (representing three food categories) were selected: Prosopis cineraria and Acacia senegal (legume), Capparis decidua and Cordia dichotoma (non-legume), and Mangifera indica (fruit), in which the first four are largely underutilized. The antioxidant capacities of individual plant extracts and their binary mixtures were analyzed by DPPH free radical scavenging and FRAP assays. The total phenolic content (TPC) and total flavonoid content (TFC) were also determined. The highest antioxidant activity was obtained for Prosopis cineraria extract (EC50—1.24 ± 0.02 mg/ml, FRAP value—380.58 ± 11.17 μM/g), while Mangifera indica exhibited the lowest antioxidant activity (EC50—2.54 ± 0.05 mg/ml, FRAP value—48.91 ± 4.34 μM/g). Binary mixture of Prosopis cineraria (legume) and Mangifera indica (fruit) manifested maximum synergy (experimental EC50—0.89 ± 0.01 mg/ml, theoretical EC50—3.79 ± 0.05 mg/ml). Correlation studies [Pearson’s correlation coefficient (r) and Principal component analysis (PCA)] showed a high correlation of TFC with DPPH and TPC with FRAP values. LC–MS analysis of methanolic plant extracts detected 43 phenolic compounds (including phenolic acids, flavonoids, and isoflavonoids), possibly responsible for the observed food synergy. For edible plants of the (semi) arid zones, this study is a first-of-its-kind and provides scientific validation to the traditional wisdom of consuming these foods together. Such indigenous food combinations derived from desert flora could offer valuable insights into development of sustainable functional foods and nutraceuticals.Graphical

GAS CHROMATOGRAPHY-MASS SPECTROMETRY CHEMICAL PROFILING AND ANTIOXIDATION ACTIVITY OF THE THAI HERBAL FORMULA “PIKAD TRISUKKHATI SAMUTHARN” EXTRACT

Pikad Trisukkhati Samutharn (PTS) is a medicinal formula used in Thai traditional medicine for treating severe fever, inflammation, and diarrhea, as well as for general health promotion. This herbal formula was made from the roots of three plants: Oroxylum indicum (L.) Kurz, Sesbania grandiflora (L.) Pers and Ficus racemosa L. The purpose of this study was to investigate the antioxidation activity and chemical profiling of PTS and its herbal components. The antioxidation activity of the extracts was determined using the DPPH free radical scavenging assay, as well as the Folin-Ciocalteu method, to investigate the total phenolic contents. The thiobarbituric acid reactive substance (TBAR) assay was used to test lipid peroxidation activity. The chemical profiling of PTS was demonstrated using gas chromatography–mass spectrometry (GC-MS) analysis. The results revealed that the total phenolic content of the ethanolic extract (79.57 ± 2.33 mg GAE/g extract) was greater than that of the aqueous extract (12.55 ± 2.83 mg GAE/g extract) of the PTS. The DPPH free radical scavenging activity of the PTS ethanolic extract (IC50 value 80.69 ± 0.40 mg/mL) was also stronger than that of the PTS aqueous extract (IC50 value 650.10 ± 98.20 mg/mL). Lipid peroxidation of the PTS ethanolic extract was moderate with 32.47 ± 0.71% inhibition. GC-MS revealed the presence of several phenolic compounds contained in the PTS ethanolic extract in which the identified compounds had previously been reported to have several pharmacological activities such as antioxidation, anti-inflammation, and antimicrobial. In conclusion, the antioxidation and chemical constituents of the PTS extract were demonstrated for the first time, and more pharmacological activities of PTS should be explored to confirm its traditional use.

Phytochemical Screening and In Vitro Antioxidant Activity of Three Nepalese Plants

Nepal is rich in plant resources and holds the 49th spot in the world’s biodiversity. The variation in altitude, climatic conditions, and geographical features across Nepal make it a rich source of Medicinal and Aromatic Plants (MAPs). The study was carried out to perform the preliminary phytochemical screening and assess antioxidant properties in Ficus neriifolia, Rubus treutleri, and Periploca calophylla. Plants were selected based on their ethnomedical use and scant scientific research. Ethanol (70%) and aqueous extracts were prepared by using the cold maceration method and preliminary phytochemical screening was conducted using the previously established method to test the presence of biologically active phytoconstituent. In vitro, antioxidant activity was examined by DPPH free radical scavenging assay. The results revealed the variation in phytoconstituents among the 70% ethanol and aqueous extracts of all three plant samples. Among the samples, the 70% ethanol extract of P. calophylla exhibited the highest antioxidant activity with an IC50 value of 94.36 μg/mL, while the aqueous extract of F. neriifolia showed the minimum antioxidant activity with an IC50 value of 902.23 μg/mL. This study indicates that these plant samples possess potent natural antioxidants capable of scavenging free radicals that cause cellular damage and contribute to various diseases in our bodies.

Antioxidant and antiproliferative effect of a glycosaminoglycan extract from Rapana venosa marine snail.

Marine glycosaminoglycans (GAG) isolated from different invertebrates, such as molluscs, starfish or jellyfish, have been described as unique molecules with important pharmacological applications. Scarce information is available on GAG extract from Rapana venosa marine snail. The aim of this study was to isolate a GAG extract from R. venosa marine snail and to investigate its physicochemical, antioxidant and antiproliferative properties for further biomedical use. The morphology, chemical and elemental composition of the extract were established as well as the sulfate content and N- to O-sulfation ratio. Fourier transform infrared (FTIR) spectra indicated that GAG extract presented similar structural characteristics to bovine heparan sulfate and chondroitin sulfate. The pattern of extract migration in agarose gel electrophoresis and specific digestion with chondroitinase ABC and heparinase III indicated the presence of a mixture of chondroitin sulfate-type GAG, as main component, and heparan sulfate-type GAG. Free radical scavenging and ferric ion reducing assays showed that GAG extract had high antioxidant activity, which slightly decreased after enzymatic treatment. In vitro MTT and Live/Dead assays showed that GAG extract had the ability to inhibit cell proliferation in human Hep-2 cell cultures, at cytocompatible concentrations in normal NCTC clone L929 fibroblasts. This capacity decreased after enzymatic digestion, in accordance to the antioxidant activity of the products. Tumoral cell migration was also inhibited by GAG extract and its digestion products. Overall, GAG extract from R. venosa marine snail exhibited antioxidant and antiproliferative activities, suggesting its potential use as novel bioactive compound for biomedical applications.

Antidiabetic activity of methanolic extract of Hibiscus sabdariffa Linn. fruit in alloxan-induced Swiss albino diabetic mice

Abstract The majority of natural diabetic medications come from fruits and vegetables. These natural medications help protect humans from negative impacts of chemical antidiabetics by scavenging free radicals. The present study aimed to explore the antioxidant and antidiabetic properties of methanolic extract of fruits of Hibiscus sabdariffa Linn. (MEHSF) in alloxan-induced Swiss albino diabetic mice. The dried coarse powder of Hibiscus sabdariffa Linn. fruits was subjected to methanol extraction. The antidiabetic activity was determined by using alloxan-induced (80 mg/kg body weight) diabetic mice. Following a 15-day treatment period, serum biochemical parameters including total cholesterol (TC), triglyceride (TAG), LDL-cholesterol (LDL), HDL-cholesterol (HDL), serum glutamic pyruvic transaminase (SGPT), and serum glutamic-oxaloacetic transaminase (SGOT) enzymes were estimated. The antioxidant activity was evaluated through a DPPH and ABTS free radical scavenging assay. Total phenolic content and total flavonoid content were assessed using established methods. MESHF, containing polyphenolic and flavonoid compounds, exhibited antioxidant properties. A 100 and 200 mg/kg significantly (p &lt; 0.05) lowered the blood glucose levels and improved biochemical parameters such as TC, TAG, LDL, and HDL in diabetic mice. Further, MESHF significantly (p &lt; 0.05) reduced the activity of the SGPT and SGOT in diabetic mice compared to untreated diabetic mice. These results suggest that MEHSF with promising antioxidant and antidiabetic potentials can be considered to be a probable new resource of the antidiabetic agent.

Extraction, characterization and the antioxidant activity of carotenoid pigment canthaxanthin from an aero-terrestrial and filamentous green microalga Trentepohlia sp.

Trentepohlia sp. (TP1) was collected from tree barks at Kodaikanal, Tamil Nadu, India. The largest amount of carotenoid pigment (5.72 %) was achieved using a 7:3 ratio of methanol to chloroform. For coconut oil, the Rf value of carotenoid pigment was 0.67 and for solvents, it was 0.95. In column chromatography, elution 2 yielded 64.096 ± 0.17 mg/mL of carotenoid using petroleum ether and acetone (9:1) as the mobile phase. Approximately 90 % of canthaxanthin was derived from purified carotenoid pigment, according to GC–MS and FT-IR analyses. The concentration of canthaxanthin was inversely proportional to free radicals generated in the DPPH free radical scavenging assay. The IC50 values of canthaxanthin from Trentepohlia sp. (TP1) was 23.37 ± 1.52 μg/mL, which was close to the positive control Ascorbic acid (22.49 ± 0.43 μg/mL). Therefore, this study reveals the prospective approach to the extraction of canthaxanthin from Trentepohlia sp. for various biotechnological applications.

Mycosynthesis of selenium nanoparticles using Penicillium tardochrysogenum as a therapeutic agent and their combination with infrared irradiation against Ehrlich carcinoma

Over the past years, the assessment of myco-fabricated selenium nanoparticles (SeNPs) properties, is still in its infancy. Herein, we have highly stable myco-synthesized SeNPs using molecularly identified soil-isolated fungus; Penicillium tardochrysogenum OR059437; (PeSeNPs) were clarified via TEM, EDX, UV–Vis spectrophotometer, FTIR and zeta potential. The therapeutic efficacy profile will be determined, these crystalline PeSeNPs were examined for antioxidant, antimicrobial, MIC, and anticancer potentials, indicating that, PeSeNPs have antioxidant activity of (IC50, 109.11 μg/mL) using DPPH free radical scavenging assay. Also, PeSeNPs possess antimicrobial potential against Penicillium italicum RCMB 001,018 (1) IMI 193,019, Methicillin-Resistant Staphylococcus aureus (MRSA) ATCC 4330 and Porphyromonas gingivalis RCMB 022,001 (1) EMCC 1699; with I.Z. diameters and MIC; 16 ± 0.5 mm and MIC 500 µg/ml, 11.9 ± 0.6 mm, 500 µg/ml and 15.9±0.6 mm, 1000 µg/ml, respectively. Additionally, TEM micrographs were taken for P. italicum treated with PeSeNPs, demonstrating the destruction of hyphal membrane and internal organelles integrity, pores formation, and cell death. PeSeNP alone in vivo and combined with a near-infrared physiotherapy lamp with an energy intensity of 140 mW/cm2 showed a strong therapeutic effect against cancer cells. Thus, PeSeNPs represent anticancer agents and a suitable photothermal option for treating different kinds of cancer cells with lower toxicity and higher efficiency than normal cells. The combination therapy showed a very large and significant reduction in tumor volume, the tumor cells showed large necrosis, shrank, and disappeared. There was also improvement in liver ultrastructure, liver enzymes, and histology, as well as renal function, urea, and creatinine.

Novel organic–inorganic hybrid dimethyltin(IV) complexes of heterocyclic carboxylic acid and N-phthaloyl amino acids: Design, synthesis, spectroscopic characterization, DFT calculations and their anti-oxidant potential

Four new organic–inorganic hybrid dimethyltin(IV) complexes (1–4) having general formula Me2SnAL which were generated by the reaction of dimethyltin(IV) dichloride with sodium salts of indole-3-acetic acid (AH) and flexible N-phthaloyl amino acids (LH) in 1:1:1 molar ratio in refluxing dry THF. The plausible structure of newly generated complexes has been elucidated on the basis of spectroscopic [IR, NMR (1H,13C,119Sn), HRMS] studies. The suggested five coordinated geometry of the hybrid dimethyltin(IV) complexes have been further supported by computational calculations using density functional theory (DFT). DFT calculations were carried out using B3LYP/6-31G* functional basis set. DFT calculations furnish an insight into the optimized geometry, optimized energy, stability, global reactivity descriptors and frontier molecular orbital (FMO) analysis of newly synthesized organic–inorganic hybrid dimethyltin(IV) complexes. These newly synthesized complexes were also evaluated for their anti-radical activity by DPPH free radical scavenging assay. All the dimethyltin(IV) complexes acted as efficient radical scavengers.

Antiarthritic and Antioxidant Activities of Antrocaryon micraster Seed Extract and Its Fractions.

Rheumatoid arthritis (RA) is an incurable debilitating disease which attacks the joints and impairs quality of life. Antrocaryon micraster is used to treat RA in African traditional medicine. However, its antiarthritic activity has not been pharmacologically studied. This study, therefore, reports the antiarthritic and antioxidant activities of A. micraster seed extract and its fractions. The seed extract (ASE) was produced by Soxhlet extraction and partitioned into petroleum ether (ASEP), ethyl acetate (ASEE), and aqueous (ASEA) fractions. The total polyphenolic content, DPPH antioxidant activity, and in vitro arthritic activity using the protein denaturation assay were evaluated for ASE and its fractions. The arthritic activity of the crude extract (ASE) and its most effective fraction (ASEA), in the in vitro assay, were then evaluated against CFA-induced arthritis in rats. The polyphenolic constituent of ASE was estimated to be 13.00 ± 0.00 mg/100 mg of GAE. ASEA contained the highest quantity of polyphenolic constituents (10.76 ± 0.00 mg/100 mg of GAE) among the fractions of the extract. ASE and ASEA produced profound antioxidant activity (IC50 = 20.17 ± 1.291 and 19.35 ± 0.865, respectively) which were similar to that of ascorbic acid (IC50 = 17.35 ± 0.500) in the DPPH free radical scavenging assay. Furthermore, in vitro antiarthritic activity of ASEA was 13.63 and 5.75 times higher than the antiarthritic activity of the crude extract and diclofenac sodium, respectively. In the CFA-induced arthritis assay, both ASE and ASEA significantly (P < 0.001) inhibited cachexia, paw edema, infiltration of inflammatory cells, pannus formation, and synovium damage. These results indicate that A. micraster seed extract and its fractions possessed significant antiarthritic activity via inhibition of oxidative stress, inflammation, protein denaturation, infiltration of inflammatory cells, and synovium injury due to its constituents such as polyphenols and phytosterols.

Cross-Linked Hyaluronan Derivatives in the Delivery of Phycocyanin.

An easy and viable crosslinking technology, based on the "click-chemistry" reaction copper(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (click-crosslinking), was applied to graft copolymers of medium molecular weight (i.e., 270 kDa) hyaluronic acid (HA) grafted with ferulic acid (FA) residues bearing clickable propargyl groups, as well as caffeic acid derivatives bearing azido-terminated oligo(ethylene glycol) side chains. The obtained crosslinked materials were characterized from the point of view of their structure and aggregation liability to form hydrogels in a water environment. The most promising materials showed interesting loading capability regarding the antioxidant agent phycocyanin (PC). Two novel materials complexes (namely HA(270)-FA-TEGEC-CL-20/PC and HA(270)-FA-HEGEC-CL-20/PC) were obtained with a drug-to-material ratio of 1:2 (w/w). Zeta potential measurements of the new complexes (-1.23 mV for HA(270)-FA-TEGEC-CL-20/PC and -1.73 mV for HA(270)-FA-HEGEC-CL-20/PC) showed alterations compared to the zeta potential values of the materials on their own, suggesting the achievement of drug-material interactions. According to the in vitro dissolution studies carried out in different conditions, novel drug delivery systems (DDSs) were obtained with a variety of characteristics depending on the desired route of administration and, consequently, on the pH of the surrounding environment, thanks to the complexation of phycocyanin with these two new crosslinked materials. Both complexes showed excellent potential for providing a controlled/prolonged release of the active pharmaceutical ingredient (API). They also increased the amount of drug that reach the target location, enabling pH-dependent release. Importantly, as demonstrated by the DPPH free radical scavenging assay, the complexation process, involving freezing and freeze-drying, showed no adverse effects on the antioxidant activity of phycocyanin. This activity was preserved in the two novel materials and followed a concentration-dependent pattern similar to pure PC.

Chemical Constituents and Antioxidant Potential of Red Guava (Psidium cattleianum Sabine) from Southern Brazil in Different Edible Ripening Stages.

Ripening and growing location are important factors that can impact fruit quality characteristics. In this study, the influence of these factors on physicochemical characteristics, carbohydrates, aliphatic organic acids, phenolic compounds, and antioxidant capacity of red guava (Psidium cattleianum Sabine) was evaluated. Fruit ripening increased fructose and glucose (up to 22.83 and 16.42g 100g- 1 dry matter (DM), respectively), and decreased citric acid, the major organic acid (up to 135.35 mg g- 1 DM). Ripening and growing location also influenced the concentration of phenolic compounds and antioxidant capacity of red guava, in which a dependency between both factors was observed in most cases. Apigenin, galangin, isoquercitrin, among other phenolic compounds were quantified for the first time in red guava, in which isoquercitrin was the major (up to 13409.81mg kg- 1 DM). The antioxidant potential of red guava was also confirmed by ferric reducing antioxidant power assay (up to 82.63 µmol Fe+ 2 g- 1 DM), Folin-Ciocalteu reducing capacity assay (up to 17.79mg gallic acid equivalent g- 1 DM), and DPPH free radical scavenging assay (up to 25.36mg ascorbic acid equivalent g- 1 DM). These results especially demonstrated the bioactive potential of red guava and provided knowledge regarding the influence of ripening and growing location on chemical and bioactive components encouraging its industrial exploitation.

Rapid Analysis of Compounds from Piperis Herba and Piperis Kadsurae Caulis and Their Differences Using High-Resolution Liquid-Mass Spectrometry and Molecular Network Binding Antioxidant Activity.

There is a serious mixing of Piperis Herba and Piperis Kadsurae Caulis in various parts of China due to the similar traits of lianas, and there is a lack of systematic research on the compound and activity evaluation of the two. Likewise, the differences in compounds brought about by the distribution of origin also need to be investigated. In this study, high-resolution liquid-mass spectrometry (UPLC-Q-Zeno-TOF-MS/MS) was used to analyze samples of Piperis Herba from five origins and Piperis Kadsurae Caulis from five origins, with three batches collected from each origin. The compounds were identified based on precise molecular weights, secondary fragments, and an online database combined with node-to-node associations of the molecular network. The t-test was used to screen and analyze the differential compounds between the two. Finally, the preliminary evaluation of antioxidant activity of the two herbs was carried out using DPPH and ABTS free radical scavenging assays. The results showed that a total of 72 compounds were identified and deduced in the two Chinese medicines. These compounds included 54 amide alkaloids and 18 other compounds, such as flavonoid glycosides. The amide alkaloids among them were then classified, and the cleavage pathways in positive ion mode were summarized. Based on the p-value of the t-test, 32 differential compounds were screened out, and it was found that the compounds of Piperis Herba were richer and possessed a broader spectrum of antioxidant activity, thus realizing a multilevel distinction between Piperis Herba and Piperis Kadsurae Caulis. This study provides a preliminary reference for promoting standardization and comprehensive quality research of the resources of Piperis Herba using Piperis Kadsurae Caulis as a reference.