H2O2 Scavenging Research Articles

Antioxidant, Protoscolicidal, Hemocompatibility, and Antibacterial Activity of Nickel Oxide Nanoparticles Synthesized by Ziziphus spina-christi

Over the past several years, the greener fabrication of metal oxide nanoparticles has attracted significant attention due to their simplicity, eco-friendliness, availability, and nontoxicity. This paper focused on the fabrication of nickel oxide nanoparticles (NiO-NPs) using the leaf extract of Ziziphus spina-christi L. and evaluating its potential biological activities. The characterization of synthesized NiO-NPs was confirmed using ultraviolet–visible spectroscopy, field emission-scanning electron microscope, energy-dispersive X-ray spectroscopy, and X-ray diffraction. Furthermore, protoscolicidal, antibacterial, and antioxidant activities and hemocompatibility of NiO-NPs were investigated. The findings revealed that the NiO-NPs were crystalline on nanoscale between 50- and 90-nm particle sizes. The NiO-NPs showed high scolicidal activity against Echinococcus granulosus. The viability of the treated protoscoleces exponentially decreased with an increase in the concentration of NiO-NPs. The NiO-NPs exhibited effective antibacterial activity against Escherichia coli and Staphylococcus aureus. NiO-NPs also possess a H2O2 scavenging activity in a dose-dependent manner. This study revealed that the Z. spina-christi L. leaf extract is an effective reducing and capping agent for the production of NiO-NPs; it showed critical biological properties. Moreover, NiO-NPs have a potent antioxidant activity and low toxicity on the erythrocytes and appear hemocompatible.

Appraisal of Antioxidant Potential of Saussurea lappa and Valeriana wallichii Root Extract by In-vitro Techniques

>Background: Antioxidants are very important in preventing and protecting from oxidative stress and, ultimately, oxidative stress-related disorders. With the aim to the antioxidant activity of Saussurea lappa and Valeriana wallichii extract, individually and in combination, the study was performed via assays for antioxidant capability; 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH), nitric oxide scavenging method, ferric reducing antioxidant power (FRAP), H2O2 scavenging potential, superoxide radical scavenging method showed good antioxidant activity. Individually, V. wallichii having more superior antioxidant activity than S. lappa. Results: Phytochemical analysis of both extracts individually illustrate the existence of anthraquinones, cardiac glycoside, flavonoids, reducing sugars, phenolics, saponins, alkaloid terpenoids, and phlobatannin. In combination, the antioxidant activity was improved, indicating additive effects. The results indicate that these herbs can be a very good constituent for combination therapy for diseases that are caused by oxidative stress and require antioxidant therapy. The S. lappa and V. wallichii showed average TPC of 68.38 and 117.52 mg GAE/g of extract, respectively. The mix of 1:1 ratio of both extracts showed TPC of 101.34 mg GAE/g. The S. lappa and V. wallichii showed average TFC of 59.72 and73.56 mg QE/g of extract, respectively. The mix of 1:1 ratio of both extracts showed a TFC of 66.15 mg QE/g of extract. Results showed that both extracts have very strong antioxidant activity. V. wallichii has relatively higher antioxidant activity and is close to that of ascorbic acid.

Antioxidant Activities of Ginger (Zingiber officinale Roscoe) and Telang Flower (Clitoria ternatea L.) Combination Tea

Tea is known as one of the favorite beverages globally, together with coffee and cocoa. Tea has been used as a health product or medicinal drug to prevent and treat various diseases. Herbal tea has become one of the most sought-after beverages often consumed by the people for health purposes. This paper reports the antioxidant activities of a herbal tea combination from dried ginger and telang flower (Clitoria ternatea), which is referred to as JaTe in Indonesian, as the abbreviation of Jahe (Ginger, Zingiber officinale) and Telang flower (Clitoria ternatea). The experiment was conducted at the general laboratory of the Biomolecular and Biomedical Research Center, Aretha Medika Utama, Bandung, West Java, Indonesia, during the period of November 2021 to the end of December 2021. The JaTe tea was made by combining 2 g dried ginger and 5 buds telang flower that were boiled in 200 mL for 5 minutes. The dried ginger tea, dried telang tea, and JaTe tea were evaluated for the antioxidant activities. The total phenolic and flavonoid content was evaluated by Folin-Ciocalte using the Gallic Acid Equivalent (GAE), while the flavonoid content was evaluated using the Quercetin Equivalent (QE) and the aluminum chloride colorimetric assay. The antioxidant activity was measured using 2,2-diphenyl-1picrylhydrazyl (DPPH) and 2,2'-Azino-Bis-3-Ethylbenzothiazoline-6-sulfonic acid (ABTS) while the hydrogen peroxide (H2O2) scavenging activities was measured using ferric reducing antioxidant power (FRAP) assay. This study showed that ginger tea, telang tea, and JaTe tea formulations have antioxidant activities due to its low IC50 values. The highest phenolic content and flavonoid content was counx in ginger tea with 23.62 μg GAE/100% concentration, followed by telang tea with 7.22 μg QE/100% concentration. JaTe tea has the strongest ABTS scavenging activity with IC50= 1.01% and FRAP activity with IC50=3.59 %. Meanwhile, the ginger tea has the strongest DPPH scavenging activity with an IC50 value of 7.76 % and an H2O2 scavenging activity with IC50=13.23 %. Overall, JaTe herbal tea formulation has a strong antioxidant activity.

The gene LpBCP increased NaHCO3 resistance by enhancing lignin or ROS scavenging in the Nicotiana benthamiana.

Lilium pumilum is an excellent wildflower germplasm resource with high resistance to salinity stress. The gene LpBCP plays an important role in salinity tolerance of L. pumilum. Studying the molecular mechanism of salinity resistance in L. pumilum will provide insights into multiple aspects, including breeding better varieties, environmental protection, improving soil conditions, etc. Conventional methods were used to determine different physiological indicators of Nicotiana benthamiana after NaHCO3 treatment, i.e. chlorophyll content, soluble phenol content and lignin content. RT-qPCR was carried out to find expression of LpBCP in different organs and under abiotic stresses. DAB was used to detect H2 O2 in leaves in situ. A yeast two-hybrid system was used to screen for LpBCP interacting proteins. LpBCP was cloned from bulbs of L. pumilum. The highest expression of LpBCP was in roots and bulbs of transgenic plants. LpBCP-overexpressed plants showed less wilting, compared to WT plants. LpBCP transgenic plants have higher chlorophyll, soluble phenol and lignin content, and lower relative conductivity under 500 mM NaHCO3 stress. In addition, H2 O2 scavenging in transgenic plants was much improved, indicating increased resistance to NaHCO3 stress. Thirteen LpBCP-interacting proteins were screened using the yeast two-hybrid method and five were associated with salt stress. Based on our findings, LPBCP could be a key gene that can be used to improve L. pumilum salt tolerance.

Analgesic, Anti-inflammatory, Antipyretic, and In Silico Measurements of Sonneratia caseolaris (L.) Fruits from Sundarbans, Bangladesh.

Sonneratia caseolaris is a widely distributed mangrove plant having much therapeutic importance in traditional medicine. This plant is reported for possessing numerous compounds that are already used for many therapeutic purposes. After finding the presence of antioxidant components in the qualitative antioxidative assay, we went to conduct quantitative tests where the total contents of phenolics, flavonoids, and tannins were estimated as 122 mg GAE/gm, 613 mg QE/gm, and 30 mg GAE/gm, respectively. In DPPH free radical, H2O2, and superoxide radical scavenging assay, the SC50 values were found to be 87, 66, and 192 μg/ml, respectively. In FeCl3 reducing power assay, the RC50 of SC extract and ascorbic acid were 80 and 28 μg/ml, respectively. This extract revealed a significant peripheral analgesic effect in the acetic acid-induced writhing model in mice by reducing the writhing impulse by about 21% and 39% at 250 and 500 mg/kg doses, respectively, and a central analgesic effect in the tail immersion method by elongating the time up to about 22% and 37% at the same doses. In the anti-inflammatory test in mice, this extract reduced the paw edema size over the observed period in a dose-dependent manner. It also showed a significant reduction in the elevated rectal temperature of mice in the observing period in Brewer's yeast-induced pyrexia model. In silico analysis revealed better binding characteristics of ellagic acid and luteolin among other compounds with various receptors that might be responsible for antioxidative and anti-inflammatory properties. From our observation, we suppose that SC fruits might be a potential source of drug leads for various inflammatory disorders.

Biosynthesis of silver nanoparticles with antibacterial, antioxidant, anti-inflammatory properties and their burn wound healing efficacy.

The current study aims to develop a novel burn wound ointment consisting of sheep’s tail ointment loaded with AgNP. The AgNP in the ointment serves as an antibacterial, antioxidant and anti-inflammatory agent. The AgNP was developed via the biological method with the assistance of the medicinal plant Rhodiola rosea. The characterization of AgNP was assessed using UV-Vis spectroscopy, FTIR, Zeta Potential, XRD, PCCS, SEM, and EDX techniques. The formation of AgNP was confirmed by UV-Vis spectrum at the absorbance of ∼430 nm, and the biomolecules responsible for reducing and capping the AgNP were characterized by FTIR analysis. The stability of AgNP was determined with Zeta potential, which revealed a highly stable colloidal solution with a surface charge of −68.38 ± 3.4 mV. The synthesized AgNP had a face-centered cubic structure with a crystallite size of 23 nm and average grain size of 67.5 nm. The SEM image showed a fairly monodisperse 20 nm-sized spherical-shaped AgNP. The synthesized AgNP contained high purity of the silver, and a low concentration of AgNP inhibited both Gram-positive and Gram-negative bacteria. Moreover, the scavenging activity of AgNP was investigated using DPPH and H2O2 scavenging assay, and the results revealed a dose-dependent antioxidant activity with the highest activity at a concentration of 450 μg/ml. Finally, the burn wound healing effect was evaluated by applying the AgNP-loaded ointment to the wound site of BALB/c mice. The in-vivo studies confirmed that AgNP-loaded ointment reduced the wound size, decreased the epidermis layer, and lowered mast cell migration compared to untreated burn wounds. And the synthesized AgNP regulated both pro-inflammatory and anti-inflammatory gene expression, thereby promoting burn wound closure on BALB/c mice. The developed AgNP-loaded ointment has the potential to be applied in the biomedical field.

OsSGT1 promotes melatonin-ameliorated seed tolerance to chromium stress by affecting the OsABI5-OsAPX1 transcriptional module in rice.

Chromium (Cr) pollution threatens plant development and growth. Application of melatonin (Mel) is emerging as an effective ally to resist stress, but how Mel ameliorates seed germination upon exposure to heavy metals is poorly understood. Here, we found (i) that seed priming with Mel considerably alleviated Cr stress during rice (Oryza sativa) seed germination and (ii) that germination performance was significantly improved in suppressor of the G2 allele of skp1 (OsSGT1) overexpression lines, while mutations of OsSGT1 and/or abscisic acid-insensitive 5 (OsABI5) noticeably abrogated such Mel-induced tolerance to Cr. Complementation assays suggested that the restored expression of OsSGT1 could not rescue the weak germination of sgt1-1abi5 under Cr stress, even upon Mel priming, but the expression of OsABI5 driven by the promoter of OsSGT1 significantly restored the Mel-ameliorated germination and the expression of ascorbate peroxidase 1 (OsAPX1) in sgt1-1abi5. Further analysis indicated that OsABI5 directly regulated the transcriptional expression of OsAPX1, whose encoding products promoted H2 O2 scavenging to maintain redox homeostasis, which is essential for germination. Collectively, this work demonstrates that OsSGT1 regulates OsABI5 to target OsAPX1, mediating the stimulatory effects of Mel on germination of Cr-stressed seeds, which provides a guide for the application of Mel in rice production.

Overexpression of tomato SlTpx improves salt stress tolerance in transgenic tobacco plants by scavenging H2O2

Hydrogen peroxide (H2O2) is an important signaling molecule that involved in multiple physiological metabolic processes in plants. Excess H2O2 can destroy biological macromolecules to poison the cell. Thioredoxin peroxidase (Tpx) plays an important role in protecting plants from oxidative damage by clearing H2O2. In this study, tomato Tpx (SlTpx) gene was cloned and bioinformatic analysis was done. The mRNA transcript level of SlTpx in tomato root and leaf was increased significantly after NaCl stress treatment for 12 h. SlTpx overexpression transgenic tobacco plants were obtained to study its function under NaCl stress. The seed germination rate of SlTpx overexpression plants was higher than that in wild type (WT) plants under NaCl treatment. The malondialdehyde (MDA) content and reactive oxygen species (ROS) accumulation in transgenic tobacco were less than in WT under NaCl stress. Transgenic plants had significantly higher antioxidant enzyme activities, proline and total soluble sugar contents, and expression of Na+ metabolism genes in transgenic plants than the WT. Moreover, The SlTpx transgenic seeds showed higher tolerance to H2O2 and methyl viologen (MV) treatment, compared with the WT. Besides, the growth of prokaryotic strain of pET-28a-SlTpx was better than the pET-28a strain with H2O2 treatment. The above results indicate that the SlTpx gene improves the plant salt tolerance by scavenging H2O2.

Comparative evaluation of in vitro antioxidant potential of Punica granatum L. leaves extracts

A comparative evaluation of tannins, flavonoid, phenol quantification and antioxidant potential of aqueous, methanol, n-hexane, acetone and chloroform extracts of Punica granatum leaves were determined. Quantification of phenolic was carried out by the technique of Folin-Ciocalteau, using rutin as standard flavonoids were evaluated through the technique of colorimetry, tannin was measured by the difference of total phenolics and free phenolics assay procedure. Antioxidant activities were evaluated by four standards antioxidant techniques including Superoxide dismutase (SOD)-like activity, Hydrogen Peroxide (H2O2) scavenging activity,1, 1’-diphynyl- 2-picrylhydrazyl (DPPH) activity and Nitric oxide (NO) scavenging activity method using ascorbic acid as standard. The antioxidant activities showed that methanol extract at 500μg/mL calculated maximum DPPH inhibition activity was 78±1%, H2O2 scavenging activity was 90±0%, SOD-like activity was 88±0% and NO scavenging activity was 90±0%. The outcomes indicated the major antioxidant actions were carried out by the extract of methanol; the entire potential was increased in the directive of methanol> chloroform> acetone>aqueous>n-hexane extracts. The results indicate that Punica granatum leaves extracts to have potent antioxidant activities that would have beneficial effects on human health and methanol extracts are superior with better antioxidant potential. The leaves extracts of Punica granatum could be of enormousattention in the enhancement of top value-added secondary products and the appliance of functional and green substitutes in thecosmetics, food and pharma industries.

Expression of CD70 Modulates Nitric Oxide and Redox Status in Endothelial Cells.

Background:Endothelial dysfunction is a critical component in the pathogenesis of cardiovascular diseases and is closely associated with nitric oxide (NO) levels and oxidative stress. Here, we report on novel findings linking endothelial expression of CD70 (also known as CD27 ligand) with alterations in NO and reactive oxygen species.Methods:CD70 expression was genetically manipulated in human aortic and pulmonary artery endothelial cells. Intracellular NO and hydrogen peroxide (H2O2) were measured using genetically encoded biosensors, and cellular phenotypes were assessed.Results:An unbiased phenome-wide association study demonstrated that polymorphisms in CD70 associate with vascular phenotypes. Endothelial cells treated with CD70-directed short-interfering RNA demonstrated impaired wound closure, decreased agonist-stimulated NO levels, and reduced eNOS (endothelial nitric oxide synthase) protein. These changes were accompanied by reduced NO bioactivity, increased 3-nitrotyrosine levels, and a decrease in the eNOS binding partner heat shock protein 90. Following treatment with the thioredoxin inhibitor auranofin or with agonist histamine, intracellular H2O2 levels increased up to 80% in the cytosol, plasmalemmal caveolae, and mitochondria. There was increased expression of NADPH oxidase 1 complex and gp91phox; expression of copper/zinc and manganese superoxide dismutases was also elevated. CD70 knockdown reduced levels of the H2O2 scavenger catalase; by contrast, glutathione peroxidase 1 expression and activity were increased. CD70 overexpression enhanced endothelial wound closure, increased NO levels, and attenuated the reduction in eNOS mRNA induced by TNFα.Conclusions:Taken together, these data establish CD70 as a novel regulatory protein in endothelial NO and reactive oxygen species homeostasis, with implications for human vascular disease.

Direct Interaction between N-Acetylcysteine and Cytotoxic Electrophile-An Overlooked In Vitro Mechanism of Protection.

In laboratory experiments, many electrophilic cytotoxic agents induce cell death accompanied by reactive oxygen species (ROS) production and/or by glutathione (GSH) depletion. Not surprisingly, millimolar concentrations of N-acetylcysteine (NAC), which is used as a universal ROS scavenger and precursor of GSH biosynthesis, inhibit ROS production, restore GSH levels, and prevent cell death. The protective effect of NAC is generally used as corroborative evidence that cell death induced by a studied cytotoxic agent is mediated by an oxidative stress-related mechanism. However, any simple interpretation of the results of the protective effects of NAC may be misleading because it is unable to interact with superoxide (O2•−), the most important biologically relevant ROS, and is a very weak scavenger of H2O2. In addition, NAC is used in concentrations that are unnecessarily high to stimulate GSH synthesis. Unfortunately, the possibility that NAC as a nucleophile can directly interact with cytotoxic electrophiles to form non-cytotoxic NAC–electrophile adduct is rarely considered, although it is a well-known protective mechanism that is much more common than expected. Overall, apropos the possible mechanism of the cytoprotective effect of NAC in vitro, it is appropriate to investigate whether there is a direct interaction between NAC and the cytotoxic electrophile to form a non-cytotoxic NAC–electrophilic adduct(s).

Comparison of in vitro and in vivo antioxidant activities of commercial fucoidans from Macrocystis pyrifera, Undaria pinnatifida, and Fucus vesiculosus

Antioxidants fucoidans from three seaweeds, Undaria pinnatifida (FUP), Macrocystis pyrifera (FMP) and Fucus vesiculosus (FFV) are sold commercially. However, it is unclear which fucoidan is the most potent antioxidant. Therefore, our objective was to compare the antioxidant activities of these fucoidans. For this purpose, six in vitro antioxidant tests were used, total antioxidant capacity, hydroxyl radical scavenging assay, ferrous and cupric chelating assay, reducing power and H2O2 scavenging assay. The data showed that the fucoidans had a low capacity to donate electrons, and a low capacity to chelate metals. The best activity obtained was in the scavenging of hydroxyl radical. When macrophages were exposed to H2O2 and fucoidans, MTT and live/dead assays showed that all fucoidans protected cells from oxidative damage. The survival rate of zebrafish embryos was significantly higher when exposed to H2O2 and fucoidans than H2O2 alone. In summary, the fucoidans evaluated were ranked according to their antioxidant activity as follows: FMP > FFV > FUP, and the results suggest that these fucoidans, mainly FMP, can be used in the formulation of medicines/foods.

Vanadium pentoxide induced oxidative stress and cellular senescence in human lung fibroblasts

Both environmental exposure to vanadium pentoxide (V2O5, V+5 for its ionic counterparts) and fibroblast senescence are associated with pulmonary fibrosis, but whether V+5 causes fibroblast senescence remains unknown. We found in a dose-response study that 2–40 μM V+5 caused human lung fibroblasts (HLF) senescence with increased senescence-associated β-galactosidase activity and p16 expression, while cell death occurred at higher concentration (LC50, 82 μM V+5). Notably, measures of reactive oxygen species (ROS) production with fluorescence probes showed no association of ROS with V+5-dependent senescence. Preloading catalase (polyethylene-conjugated), a H2O2 scavenger, did not alleviate the cellular senescence induced by V+5. Analyses of the cellular glutathione (GSH) system showed that V+5 oxidized GSH, increased GSH biosynthesis, stimulated cellular GSH efflux and increased protein S-glutathionylation, and addition of N-acetyl cysteine inhibited V+5-elevated p16 expression, suggesting that thiol oxidation mediates V+5-caused senescence. Moreover, strong correlations between GSSG/GSH redox potential (Eh), protein S-glutathionylation, and cellular senescence (R2 > 0.99, p < 0.05) were present in V+5-treated cells. Studies with cell-free and enzyme-free solutions showed that V+5 directly oxidized GSH with formation of V+4 and GSSG in the absence of O2. Analyses of V+5 and V+4 in HLF and culture media showed that V+5 was reduced to V+4 in cells and that a stable V+4/V+5 ratio was rapidly achieved in extracellular media, indicating ongoing release of V+4 and reoxidation to V+5. Together, the results show that V+5-dependent fibroblast senescence is associated with a cellular/extracellular redox cycling mechanism involving the GSH system and occurring under conditions that do not cause cell death. These results establish a mechanism by which environmental vanadium from food, dietary supplements or drinking water, can cause or contribute to lung fibrosis in the absence of high-level occupational exposures and cytotoxic cell death.

Apoptotic and Antioxidant Activity of Gold Nanoparticles Synthesized Using Marine Brown Seaweed: An In Vitro Study.

A major paradigm shift in the field of nanobiotechnology is the invention of an eco-friendly, economical, and green approach for synthesis of metal nanoparticles. In the present study, we have synthesized gold nanoparticles (AuNPs) using aqueous extracts of marine brown seaweed Sargassum longifolium. The synthesized nanoparticle was subjected to characterization using different techniques such as UV-Vis spectroscopy, Fourier transform infrared spectroscopy, atomic force microscope, scanning electron microscope, transmission electron microscope, and elemental dispersive X-ray diffraction. Further, the seaweed extract and the synthesized AuNPs were evaluated for its anticancer effect using MG-63 human osteosarcoma cells besides in vitro antioxidant effect. The formation of S. longifolium-mediated synthesis of gold nanoparticles was demonstrated by UV-Vis spectroscopy. Presence of elemental gold was confirmed by EDX analysis. TEM analysis demonstrated spherical morphology of the synthesized AuNPs and SEM analysis revealed the particle size to be in the range of 10-60 nm. The FTIR showed the presence of hydroxyl functional groups. The toxicity of S. longifolium extract and the synthesized AuNPs was tested using brine shrimp lethality assay at different concentrations with results showing both seaweed extract and AuNPs to be nontoxic. Both S. longifolium and AuNPs exhibited significant antioxidant activity by scavenging DPPH free radicals and H2O2 radicals. Significant antiproliferative effect was observed against MG-63 osteosarcoma cells. It was also shown that the seaweed extract and the AuNPs induced cytotoxicity in cell lines by mechanism of apoptosis. In conclusion, this study provided insight on AuNPs synthesized from S. longifolium as a potent antioxidant and anticancer agent.

SUGAR AND PROTEIN CONTENT, HYDROGEN PEROXIDE RADICAL SCAVENGING AND TOTAL ANTIOXIDANT CAPACITY OF Polianthes tuberosa L FLOWERS GROWN IN ALGERIA

Tuberose flowers (Polianthes tuberosa L.) belong to the Amaryllidaceae family and they are widely enhanced through their absolute and essential oils, especially in the perfume industry. However, the sugar and proteins of tuberose are still unknown. For this reason, this work aimed to quantify them, particularly in flowers, besides to the evaluation of their hydrogen peroxide radical scavenging and total antioxidant capacity. The obtained results revealed 79.51±0.08 mg glucose equivalent/g extract of sugar and 0.097±0.001 mg bovine serum albumin equivalent/g extract of proteins. These metabolites were quantified using phenol-sulfuric acid and Coomassie Blue methods, respectively. Furthermore, the antioxidant activity of flower extract was investigated using total antioxidant capacity (TAC) and hydrogen peroxide radical scavenging. The TAC assay indicated the inhibitory concentration of 50% of free radicals (IC50) was 0,09±0,01 mg/mL of flower extract, however, the scavenging ability against H2O2 showed the IC50 of 7,09±0,15 mg/mL of tuberose flower extract. This work contributes to the knowledge of tuberose flowers content in proteins and sugar, in addition to the total antioxidant and the H2O2 scavenging capacities.

Evaluation of the in vitro antioxidant, antidiabetic and anticholinergic properties of rosmarinic acid from rosemary (Rosmarinus officinalis L.)

In this study, antidiabetic, anticholinergic, and antioxidant abilities of rosmarinic acid were evaluated and compared to standards. To determine its antioxidant activity different in vitro bioanalytical methods, including total antioxidant activity (TAA), ABTS•+ scavenging activity, O2•- scavenging activity, DPPH· scavenging activity, DMPD•+ scavenging activity, potassium ferric cyanide reduction ability, cupric ion (Cu2+) reduction capacity, H2O2 scavenging activity, and ferrous ions (Fe2+) binding activities were separately performed. Also, butylated hydroxyanisole (BHA), Trolox, α-tocopherol, and butylated hydroxytoluene (BHT) were used as the reference antioxidants. Rosmarinic acid inhibited the linoleic acid emulsion peroxidation by 89.2% while BHA, BHT, Trolox and α-tocopherol inhibited as 87.3, 97.6, 90.3 and 75.3%, respectively, at the same concentration (30 μg/mL). When these results are evaluated, rosmarinic acid had effective TAA than BHA and α-tocopherol and close to BHT and Trolox. In addition, rosmarinic acid exhibited Kİ values of 9.67 ± 0.81 nM towards acetylcholinesterase (AChE) and 33.56 ± 2.96 nM against α-glycosidase enzymes.

Phenolic profile, antioxidant, DNA protection, acetylcholinesterase, butyrylcholinesterase and urease inhibition activities of Coriandrum sativum L. leaf, seed and flower extracts

In this study, chemical content, antioxidant activities, enzyme inhibition activities, and DNA protection activities of extracts obtained from different solvents of the Coriandrum sativum leaf, flower and seed were determined. Total phenol and flavonoid contents of C. sativum leaf, seed and flower hexane extracts were higher than water, methanol, ethanol and ethyl acetate extracts. The highest anthocyanin content was found in the flower part of C. sativum. From the antioxidant activity tests, total antioxidant activity of flower aqueous extract, reducing power of seed aqueous extract, H2O2 scavenging activity of leaf ethyl acetate extract, OH˙ radical scavenging activity of leaf hexane extract, free radical scavenging activity of flower methanol extract, metal chelate activity of leaf ethyl acetate extract, superoxide anion scavenging activity of leaf aqueous extract and lipid peroxidation inhibition activity of the leaf ethyl acetate extract had the highest. It was found that the urease inhibition activity of the seed methanol extract and the acetylcholinesterase and butyrylcholinesterase inhibition activities of the seed ethanol extract presented effective inhibition activity as 80.30±0.20%, 112.83±10.75 µg/mL, and 334.28±23.09 µg/mL, respectively. The leaf hexane, flower ethyl acetate, and leaf methanol extracts showed the highest DNA protection activities with values of 71.86%, 70.89%, and 69.38%, respectively. According to the phytochemical content and biochemical activity results, this study is a valuable report proving that the C. sativum plant is a natural effective product.

Antioxidant and cytoprotective properties of seeds and seed by-products from lotus (Nelumbo nucifera)

The seed of Nelumbo nucifera Gaertn., commonly known as Chinese lotus, has been used as an indigenous medicine in Taiwan. The present study aims to evaluate the variable antioxidant activity of Nelumbo nucifera ethanolic extracts (NNEE) collected from different parts of the lotus. The seed epicarp had significantly higher extractable total phenolic content (TPC) and flavonoid content (TFC) than the seed and seed pod. Compared to the seed and seed pod, the seed epicarp also exhibited lower IC50 values of 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS), EC50 for reducing power, and hydrogen peroxide (H2O2) scavenging activity. Moreover, DPPH and ABTS radicals, reducing power activity, and H2O2 scavenging activity by NNEE were highly and significantly associated with TPC and TFC. Seed epicarp NNEE at a concentration of 25 μg/mL gave significantly higher protection to Raw 264.7 mouse macrophages against H2O2 induced damage compared with blanks. Seed epicarp NNEE was also found to have the most significant protection effect on oxidative DNA damage. Therefore, the NNEE of seed epicarp exhibited higher in vitro and ex vivo antioxidant activity, and can be used as a functional ingredient representing a potential source of natural antioxidants to prevent and treat oxidative stress-related disorders.

A New Class of Water‐Soluble Aryl Sulfonium Decavanadates and Their Antioxidant Activity: Effects of Cluster Reduction and Counter Ion Substitution on Activity

AbstractThe development of biocompatible and water‐soluble inorganic antioxidants is important, given the increasing demand for antioxidants worldwide. Polyoxovanadate (POV) clusters have been extensively explored for several biological applications, but the antioxidant properties of POVs remain largely unexplored. Herein, we developed a series of water‐soluble aryl sulfonium decavanadate ([V10O28]6−) hybrids and studied their antioxidant properties. The hybrids were characterized by several analytical and spectroscopic techniques such as ESI‐MS, XPS, and single‐crystal XRD analyses. The antioxidant properties of these hybrids were explored under native and photochemically reduced conditions using standard in vitro antioxidant assays such as H2O2 scavenging assay, lipid peroxidation inhibitory assay, DPPH radical scavenging assay, and reducing power assay. These analyses showed that these aryl sulfonium POV hybrids exhibit comparable or better antioxidant activities than the parent [V10O28]6− cluster and the standard ascorbic acid in some of the assays studied. The cytotoxicity studies using MG‐63 cells revealed that these hybrids exhibit moderate cytotoxicity. Further, it was found that introducing a phenolic functional group on the counter ion moiety helps to improve the overall antioxidant properties of the POV‐based hybrids. The present study, therefore, reports a series of water‐soluble aryl sulfonium polyoxometalate hybrids‐based antioxidants for the first time. However, more toxicological studies using similar hybrids are required to fully understand the biocompatible nature of these systems before considering their potential biological applications.

Phytochemical analysis of Portulaca oleracea leaves extract and study the role in protecting genomic human DNA from UV damage

Purslane which is the common name for Portulaca oleracea L. is a weed plant distributed all over the world and it has significant medicinal uses due to its present high percentage of phytochemical compounds. However, previous studies by researchers confirmed possession of Purslane leaves extracts anti-oxidant efficacy. Therefore, our study aims to determine the phytochemical composition of the ethanolic leaves extract of purslane and radiation-stimulated DNA damage protecting. Gas chromatography-mass spectrometry (GC-MS) analyses in the present research explore active constituents for P. oleracea, which are 17 active compounds most they are terpenoids and alkaloids. The extract showed considerable antioxidant activity and the highest inhibition-percentage (44.45 %) belongs to (20mg/ml) of an extract with an IC50 value of 4.6 mg/ml in H2O2 scavenging test and prevented DNA oxidative damage stimulated by hydrogen peroxide and ultraviolet light (UV/H2O2) at concentrations of (2-20 mg/mL). These findings suggest that the ethanolic leaves extract of P. oleracea, could be used as skin-care products to prevent UV-induced damage to the skin..