Potent Scavenging Activity Research Articles

Thymol, a dietary monoterpene phenol abrogates mitochondrial dysfunction in β-adrenergic agonist induced myocardial infarcted rats by inhibiting oxidative stress

Mitochondrial dysfunction has been suggested to be one of the important pathological events in isoproterenol (ISO), a synthetic catecholamine and β-adrenergic agonist induced myocardial infarction (MI). In this context, we have evaluated the impact of thymol against ISO induced oxidative stress and calcium uniporter malfunction involved in the pathology of mitochondrial dysfunction in rats. Male albino Wistar rats were pre and co-treated with thymol (7.5 mg/kg body weight) daily for 7 days. Isoproterenol (100 mg/kg body weight) was subcutaneously injected into rats on 6th and 7th day to induce MI. To explore the extent of cardiac mitochondrial damage, the activities/levels of cardiac marker enzymes, mitochondrial lipid peroxidation products, antioxidants, lipids, calcium, adenosine triphosphate and multi marker enzymes were evaluated. Isoproterenol induced myocardial infarcted rats showed a significant increase in the activities of cardiac diagnostic markers, heart mitochondrial lipid peroxidation, lipids, calcium, and a significant decrease in the activities/levels of heart mitochondrial superoxide dismutase, catalase, glutathione peroxidase, reduced glutathione, isocitrate, malate, α-ketoglutarate and NADH-dehydrogenases, cytochrome-C-oxidase, and adenosine triphosphate. Thymol pre and co-treatment showed near normalized effects on all the biochemical parameters studied. Transmission electron microscopic findings and mitochondrial swelling studies confirmed our biochemical findings. The in vitro study also revealed the potent free-radical scavenging activity of thymol. Thus, thymol attenuates the involvement of ISO against oxidative stress and calcium uniporter malfunction associated with mitochondrial dysfunction in rats.

Evaluation of DNA Binding, Radicals Scavenging and Antimicrobial Studies of Newly Synthesized N-Substituted Naphthalimides: Spectroscopic and Molecular Docking Investigations.

In this study, we investigated a new series of naphthalimide based Schiff base compounds as potential DNA binding, antioxidant and antimicrobial agents. The structural characterization of synthesized compounds was carried out with the aid of elemental analysis and spectroscopic techniques (UV-vis., IR, (1)H and (13)C NMR). The DNA binding properties of target compounds against Ct-DNA (calf thymus) have been investigated in detail by numerous biophysical techniques (UV-vis, fluorescence, ethidium bromide displacement assay, Time resolved fluorescence, viscosity, cyclic voltammetry and circular dichorism) and the evidences have suggested that the test compounds could interact with DNA via intercalative binding. The extent of DNA binding (Kb) of these compounds follow the order of 3b (3.33 × 10(4)M(-1)) > 3a (2.25 × 10(4)M(-1)) > 3c (2 × 10(4)M(-1)), suggesting that compound 3b binds more strongly to Ct- DNA than the compounds 3a and 3c. Molecular docking results further support intercalative binding of test compounds with DNA. The binding energies of docked compounds (3a-3c) were found to be -8.20 to -8.69kcal/ mol, suggesting greater binding affinity to Ct-DNA. The synthesized compounds displayed potential antimicrobial activities against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae and Salmonella typhimurium. Compound 3c has emerged as most active against all the four tested bacterial strains with MIC value in the range of 0.031-0.062mg/mL. In the mutagenicity studies, all the test compounds were found to be non-mutagenic both in the presence and absence of metabolic activation. Furthermore, the antioxidant activity experiments show that these compounds exhibited potential scavenging activities against DPPH and H2O2 radicals.

Abstract 263: Therapeutic Potential of a Novel Necrosis Inhibitor in Myocardial Ischemia-reperfusion Injury

Background: Reperfusion, although essential for salvage of ischemic myocardium, paradoxically causes a wide variety of injuries. Opening of mitochondrial permeability transition pore (mPTP) and Ca 2+ overload contribute to myocardial ischemia-reperfusion (I/R) injury. We aimed to investigate the protective role of a novel necrosis inhibitor (NecroX-7; NecX) against myocardial I/R injury, using in vitro and in vivo models. Methods and Results: In H9C2 rat cardiomyoblasts exposed to hypoxia-reoxygenation stress, the main mechanism of cell death was not apoptosis but necrosis, which was prevented mainly by NecX, the necrosis inhibitor, but not by Z-VAD-fmk, the apoptosis inhibitor. The protective effect of NecX was based on its potent ROS scavenging activity, especially on mitochondrial ROS which is one of the major inducers of mPTP opening. NecX preserved mitochondrial membrane potential, mitochondrial structure, through prevention of Ca 2+ influx and inhibition of the opening of mPTP. Inhibition of necrosis by NecX was accompanied by reduction of phospho-p38 MAPK and phospho-JNK, and decrease of HMGB1. Using Sprague-Dawley rats exposed to myocardial ischemia for 45 minutes followed by reperfusion, we compared therapeutic efficacies of NecX and Ciclosporin A (CsA) with 5% dextrose (control), each administrated 5 minutes before reperfusion. NecX markedly inhibited myocardial necrosis, reduced fibrotic area and attenuated the release of cardiac enzymes, compared to dextrose and CsA. Additionally, NecX preserved systolic function and prevented pathologic dilatory remodeling of left ventricle. Conclusion: The novel necrosis inhibitor has a significant protective effect against myocardial I/R injury, indicating that it is a promising candidate for cardioprotective adjunctive measure on top of reperfusion therapy. Clinical implication: We are trying to translate this experimental data into patients. A phase I clinical trial confirmed the safety profiles of NecX [NCT01737424] and a phase II trial for STEMI patients (NEXsteMI trial) is ongoing [NCT02070471].

In vitro evaluation of the antioxidant and antimicrobial activity of DIMBOA [2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one

The aim of this study was to evaluate the in vitro antioxidant and antimicrobial properties of the natural cyclic hydroxamic acid: 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA). Antioxidant activity of the isolated DIMBOA was examined using DPPH, FRAP and ABTS tests. It was found that DIMBOA exhibits a potent free-radical scavenging activity and a weaker iron (III) ions reducing activity. Antimicrobial activity against selected G(+), G(–) bacterial strains and against yeasts-like reference strains of fungi was investigated using disk-diffusion method. It has been shown that DIMBOA possess growth inhibitory properties against many strains of studied bacteria and fungi, such as Staphylococcus aureus, Escherichia coli as well as against Saccharomyces cerevisiae.

Cytotoxic and Antioxidant Activities of<i> Antidesma thwaitesianum</i> Müll Arg (Euphorbiaceae) Fruit and Fruit Waste Extracts

Purpose: To investigate the cytotoxic and antioxidant activities of the fruit and fruit waste (residue and marc) extracts of Antidesma thwaitesianum Müll. Arg., known as mamao in Thai, using chemical and cell-based assays.Methods: The cytotoxicity of mamao fruit and fruit waste extracts obtained by expression, maceration and decoction against a panel of six human cancer cell lines (COR-L23, A549, LS174T, PC-3, MCF7 and HeLa) was determined by sulforhodamine B (SRB) assay. In addition, their antioxidant activities were measured by chemical methods: 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical scavenging assay and ferric ion reducing antioxidant power (FRAP) assay and cell-based methods: nitroblue tetrazolium (NBT) dye reduction assay and nitric oxide (NO) scavenging assay. The phenolic and flavonoid contents were assessed colorimetrically at 765 nm and 415 nm respectively.Results: Among the test extracts, the ethanol extracts of fresh fruits (FME) and marc left after squeezing fresh fruits (MME) exhibited moderate cytotoxicity against human breast MCF7 cells while the extract obtained by decocting the residue left after maceration of dried fruits (RDW) was moderately cytotoxic to lung large cell carcinoma COR-L23 cells. In the chemical assays, the extract obtained by decocting the residue left after maceration of dried marc (RMW) displayed the strongest ABTS radicalscavenging and ferric-reducing activities among the extracts. In the cell-based assays, however, FME and DME exerted potent nitric oxide scavenging activity whereas the extract obtained by decocting the residue left after maceration of fresh fruits (RFW) showed moderate superoxide radical-scavenging activity relative to the test extracts. The ABTS radical-scavenging and ferric-reducing activities of these extracts strongly correlate with their phenolic and flavonoid contents, indicating their specific contributions to such activities.Conclusion: The ethanol extracts of fresh and dried mamao fruits exhibit both cytotoxic and cellular antioxidant activities, and thus possess great potentials for application in the development of effective dietary supplements to prevent oxidative stress-induced diseases.Keywords: Antidesma thwaitesianum Müll. Arg., Cytotoxicity, Lung cell carcinoma, Antioxidant activity, Cellular assays

Neuroprotective and antioxidant effects of novel benzofuran-2-carboxamide derivatives.

In the present study, we synthesized a series of novel 7-methoxy-N-(substituted phenyl)benzofuran-2-carboxamide derivatives in moderate to good yields and evaluated their neuroprotective and antioxidant activities using primary cultured rat cortical neuronal cells and in vitro cell-free bioassays. Based on our primary screening data with eighteen synthesized derivatives, nine compounds (1a, 1c, 1f, 1i, 1j, 1l, 1p, 1q and 1r) exhibiting considerable protection against the NMDA-induced excitotoxic neuronal cell damage at the concentration of 100 μM were selected for further evaluation. Among the selected derivatives, compound 1f (with -CH3 substitution at R2 position) exhibited the most potent and efficacious neuroprotective action against the NMDA-induced excitotoxicity. Its neuroprotective effect was almost comparable to that of memantine, a well-known NMDA antagonist, at 30 μM concentration. In addition to 1f, compound 1j (with -OH substitution at R3 position) also showed marked anti-excitotoxic effects at both 100 and 300 μM concentrations. These findings suggest that -CH3 substitution at R2 position and, to a lesser degree, -OH substitution at R3 position may be important for exhibiting neuroprotective action against excitotoxic damage. Compound 1j was also found to scavenge 1,1-diphenyl-2-picrylhydrazyl radicals and inhibit in vitro lipid peroxidation in rat brain homogenate in moderate and appreciable degrees. Taken together, our structure-activity relationship studies suggest that the compound with -CH3 substitution at R2 and -OH substitution at R3 positions of the benzofuran moiety might serve as the lead exhibiting potent anti-excitotoxic, ROS scavenging, and antioxidant activities. Further synthesis and evaluation will be necessary to confirm this possibility.

Juniperus chinensis and the functional compounds, cedrol and widdrol, ameliorate α-melanocyte stimulating hormone-induced melanin formation in B16F10 cells

Anti-melanogenic activities of Juniperus chinensis methanol extracts (JCM) and isolation of functional compounds were investigated. JCM possessed potent anti-oxidative and tyrosinase inhibitory activities. α-Melanocyte stimulating hormone (α-MSH)-induced melanogenesis and tyrosinase activity were inhibited by JCM in B16F10 cells. JCM also possessed potent scavenging activities against hydrogen peroxide induced reactive oxygen species (ROS). The dichloromethane (CH2Cl2) solvent fraction only exhibited an anti-melanogenic activity with a potent ROS scavenging potential. The main compounds in the CH2Cl2 fraction were cedrol (CR) and widdrol (WR), which inhibited melanogenesis both individually and synergistically. As the results, J. chinensis possesses potent anti-oxidative and anti-melanogenic activities due to active compounds, CR and WR. J. chinensis, CR, and WR provide promising new strategies for anti-oxidative and depigmenting resources.

Antioxidant activity of polysaccharide purified from Acanthopanax koreanum Nakai stems in vitro and in vivo zebrafish model

In this study, the antioxidative effects of a purified polysaccharide isolated from the stems of Acanthopanax koreanum Nakai (ASP) on hydrogen peroxide-induced oxidative stress was investigated both in vitro and in vivo using a zebrafish model. A. koreanum Nakai stem was hydrolyzed using five carbohydrases and five proteases for the enzyme-assistant extraction. Of the enzyme-assistant extracts, the Protamex extract exhibited the highest yield and a potent scavenging activity against free radicals. Ethanol-added separation and anion exchange chromatography were conducted to identify the active polysaccharide. The purified polysaccharide significantly scavenged hydrogen peroxide and reduced hydrogen peroxide-induced cell death in Vero cells and in zebrafish. The results reveal that ASP is a useful antioxidant polysaccharide and might be available for relevant industrial applications.

Enhancement of β-secretase inhibition and antioxidant activities of tempeh, a fermented soybean cake through enrichment of bioactive aglycones

Context: Soybean and its fermented products are the most common source of isoflavones in human food.Objective: The present study quantifies the major glycosides and aglycones in soybean and its fermented product tempeh isoflavone extracts. The comparision of antioxidant effects and BACE1 inhibitory activity between the isoflavones of soybean and tempeh were also established.Materials and methods: The major isoflavones such as daidzein and genistein (aglycones), and their sugar conjugates (glycosides) daidzin and genistin in soybean and tempeh isoflavones were quantified using HPLC analysis. Comparative studies on BACE 1 (β-site amyloid precursor protein cleaving enzyme 1 or β-secretase 1) inhibition and free-radical scavenging activities (diphenyl-1-picrylhydrazyl (DPPH) and ferrous ion chelating ability) were conducted.Results: The amount of actives (mg/100 g) in soybean isoflavone compared with tempeh isoflavone is as follows: daidzein 16.72 mg/100 g versus 38.91 mg/100 g, genistein 11.10 mg/100 g versus 24.03 mg/100 g, daidzin 6.16 mg/100 g versus 0.69 mg/100 g, and genistin 24.61 mg/100 g versus 6.57 mg/100 g. The IC50 values of soybean and tempeh isoflavones against BACE1 were 10.87 and 5.47 mg/ml, respectively. The tempeh isoflavone had a more potent DPPH free-radical scavenging activity (IC50 = 2.67 mg/ml) than the soybean isoflavone (IC50 = 10 mg/ml). The ferrous ion chelating ability of the isoflavones was practically similar (IC50 = 10.40 mg/ml, soybean and 11.13 mg/ml, tempeh).Discussion and conclusion: The present study indicates that tempeh is a healthy supplement to alleviate oxidative stress through the enrichment of aglycones.

Protective effects of Lycium barbarum polysaccharides against carbon tetrachloride-induced hepatotoxicity in precision-cut liver slices in vitro and in vivo in common carp (Cyprinus carpio L.)

The protective effects of Lycium barbarum polysaccharides (LBPs) against carbon tetrachloride-induced hepatotoxicity in common carp were investigated in vitro and in vivo. Precision-cut liver slices (PCLSs) were employed as an in vitro model system. LBPs (0.1, 0.3 and 0.6mg/ml) was added to PCLSs culture system before (pre-treatment), after (post-treatment) and both before and after (pre- and post-treatment) the exposure of PCLSs to 12mM CCl4. The supernatants and PCLSs were collected for biochemical analyses. Results showed that LBPs inhibited the elevations of the marker enzymes (GOT, GPT, LDH and AKP) and MDA induced by CCl4 in all LBPs treatments and it also enhanced the suppressed antioxidant enzymes (SOD, CAT, GSH-Px, GST) and GSH, in the pre-treatment and pre- and post-treatment. In vivo, fish were fed diets containing LBPs at 0.1, 0.5 and 1% for 60d before an intraperitoneal injection of 30% CCl4 in olive oil at a volume of 0.05ml/10g body weight. At 72h post-injection, blood and liver samples were taken for biochemical analyses. Results showed that LBPs at 0.5 and 1% significantly reduced the levels of GOT, GPT and LDH in the serum; the decreases of the antioxidant enzymes and the increase of MDA in the liver tissue were inhibited markedly. Moreover, LBPs even at lower concentration exerted a potent DPPH scavenging activity. Overall results prove the hepatoprotective and antioxidant effects of LBPs and support the use of LBPs as a hepatoprotective agent in fish.

Assessment of in vitro antioxidant and antimicrobial properties of cultivated Pleurotus ostreatus: An edible mushroom

Objectives: In this study, Pleurotus ostreatus was cultivated under the laboratory condition and investigated for its in vitro antioxidant and antimicrobial property. Materials and Methods: To study the total antioxidant activity we performed 2,2’-azinobis-3-ethylbenzothiazoline-6-sulfdonic acid, 1,1-diphenyl-2-picrylhydrazyl, superoxide anion, hydroxy radical-scavenging assays. Result: The P. ostreatus ethanolic extract (POEet) exhibited potent scavenging activity there by Posses increased antioxidant capacity when compared with positive control ascorbic acid. Moreover, we extended our work to investigate the antimicrobial activity of POEet which showed increasing zone of inhibition of extract with Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia. Conclusion: Our finding confirms that P. ostreatus is a potent natural antioxidant and act as prevailing antimicrobial agent to promote public health by making it as a part of normal diet to reduce the risk of various diseases.

Decaisnea insignis 에탄올 추출물의 항산화 및 항염증 활성

This study was conducted to explore new nutraceutical resources from the plant kingdom possessing biological activities. To fulfill this purpose, the anti-oxidative and anti-inflammatory activities of Decaisnea insignis ethanol extract (DIEE) were evaluated. First, DIEE possessed potent scavenging activity against 1,1-diphenyl-2-picryl hydrazyl (DPPH), similar to ascorbic acid used as a positive control. Moreover, DIEE inhibited lipopolysaccharide (LPS)- and hydrogen peroxide ()-induced reactive oxygen species (ROS) in RAW 264.7 cells. Furthermore, DIEE induced the expression of an anti-oxidative enzyme, heme oxygenase 1 (HO-1), and its upstream transcription factor, nuclear factor-E2-related factor 2 (Nrf2), in a dose-dependent manner. The modulation of the HO-1 and Nrf2 expressions might be regulated by mitogen-activated protein kinases (MAPKs) and their upstream signaling pathways. On the other hand, DIEE suppressed LPS-induced nitric oxide (NO) formation without cytotoxicity. The inhibition of the NO formation was the result of the downregulation of inducible NO synthase (iNOS) by DIEE. The suppression of NO and iNOS by DIEE might be modulated by their upstream transcription factors, nuclear factor (), and activator protein 1 (AP-1) pathways. Taken together, these results provide important new insights that D. insignis possesses anti-oxidative and anti-inflammatory activities. Therefore, it might be utilized as a promising material in the field of nutraceuticals.

Characterization and antioxidant activities of the polysaccharides from Radix Cyathulae officinalis Kuan

A water-soluble polysaccharide (PSRC) was extracted and purified from the roots of Radix Cyathulae officinalis Kuan, and its chemical characteristics, monosaccharide composition and antioxidant activities were characterized. The average of molecular weight (Mw) of PSRC was 182kDa. The majority of monosaccharide components of PSRC was glucose (relative mass 48.8%) with lower levels of mannose, rhamnose, galactose, fructose and arabinose (relative mass of 15.7, 14.3, 10.6, 6.1 and 4.5%, respectively). In vitro assays revealed that RSRC possessed potent scavenging activities against DPPH, hydroxyl and superoxide anion radicals. Oral administration of PSRC significantly enhanced antioxidant enzyme activities (including total superoxide dismutase, copper-zinc superoxide dismutase (Cu,Zn-SOD), manganese superoxide dismutase (Mn-SOD), glutathione peroxidase and catalase (CAT)) and capacities of scavenging superoxide anion and hydroxyl radicals, markedly lowered lipid peroxidation formation of malondialdehyde and significantly up-regulated mRNA expressions of Cu,Zn-SOD, Mn-SOD, CAT, glutathione peroxidase 1, thioredoxin 1 and thioredoxin 2, in a d-galactose-induced aging mouse model. Taken together, these findings demonstrate that PSRC could be used as a novel promising source of natural antioxidants and antiaging drugs.

Ardisia arborescens 에탄올 추출물의 항산화 및 항염증 활성

In this study, the antioxidative and anti-inflammatory activities of Ardisia arborescens ethanol extract (AAEE) were evaluated using in vitro assays and a cell culture model system. AAEE exhibited potent scavenging activity against 1,1-diphenyl-2-picryl hydrazyl (DPPH), similar to ascorbic acid, which was used as a positive control. Moreover, AAEE effectively suppressed lipopolysaccharide (LPS)- and hydrogen peroxide (H₂O₂)-induced reactive oxygen species (ROS) in RAW 264.7 cells. Furthermore, AAEE induced the expression of antioxidative enzymes, heme oxygenase 1 (HO-1), and thioredoxin reductase 1 (TrxR1), in addition to their upstream transcription factor, nuclear factor-E2-related factor 2 (Nrf2), in a dose-dependent manner. The upstream signaling pathways of mitogen-activated protein kinases (MAPKs) might regulate the modulation of HO-1, TrxR1, and Nrf2 expression. On the other hand, AAEE inhibited LPS-induced nitric oxide (NO) formation, without cytotoxicity. Suppression of NO formation was the result of AEEE-induced down-regulation of inducible NO synthase (iNOS). The suppression of NO and iNOS by AAEE might be modulated by their upstream transcription factor, nuclear factor (NF)-κB, and activator protein (AP)-1 pathways. Taken together, these results provide important new insights into the antioxidative and anti-inflammatory activities of A. arborescens. AAAEE might represent a promising material in the field of nutraceuticals.

Effect of a gluten-free diet on bone mineral density in children and adolescents with celiac disease

The protective effects of Lycium barbarum polysaccharides (LBPs) against carbon tetrachloride-induced hepatotoxicity in common carp were investigated in vitro and in vivo. Precision-cut liver slices (PCLSs) were employed as an in vitro model system. LBPs (0.1, 0.3 and 0.6 mg/ml) was added to PCLSs culture system before (pre-treatment), after (post-treatment) and both before and after (pre- and post-treatment) the exposure of PCLSs to 12 mM CCl4. The supernatants and PCLSs were collected for biochemical analyses. Results showed that LBPs inhibited the elevations of the marker enzymes (GOT, GPT, LDH and AKP) and MDA induced by CCl4 in all LBPs treatments and it also enhanced the suppressed antioxidant enzymes (SOD, CAT, GSH-Px, GST) and GSH, in the pre-treatment and pre- and post-treatment. In vivo, fish were fed diets containing LBPs at 0.1, 0.5 and 1% for 60 d before an intraperitoneal injection of 30% CCl4 in olive oil at a volume of 0.05 ml/10 g body weight. At 72 h post-injection, blood and liver samples were taken for biochemical analyses. Results showed that LBPs at 0.5 and 1% significantly reduced the levels of GOT, GPT and LDH in the serum; the decreases of the antioxidant enzymes and the increase of MDA in the liver tissue were inhibited markedly. Moreover, LBPs even at lower concentration exerted a potent DPPH scavenging activity. Overall results prove the hepatoprotective and antioxidant effects of LBPs and support the use of LBPs as a hepatoprotective agent in fish.

Synthesis, Antioxidant, Anticancer and Antiviral Activities of Novel Quinoxaline Hydrazone Derivatives and their Acyclic C-Nucleosides

The present investigation describes the synthesis of a new series of aldehydo-sugar-N-(3-phenylquinoxalin-2- yl)hydrazones 3a-d and their acyclic C-nucleoside analogs, 1-(4-phenyl-[1,2,4]triazolo[4,3-a]quinoxalin-1-yl)alditols 7ad by using 2-hydrazino-3-phenylquinoxaline 1 as key intermediate. The synthesized compounds were screened for their antioxidant activities by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging method. Compounds 3d and 7a, showed potent scavenging activities against ABTS(+) radicals and were found to be the most potent antioxidants described in this study. Out of the synthesized compounds, compounds 3d and 7a were selected by the National Cancer Institute for evaluation of their in vitro anticancer activity. Results revealed that compounds 3d and 7a exhibited non-selective broad spectrum activity against all cancer cell lines between 10(-6) to 10(-5) molar concentrations. Compound 3d showed the highest sensitivity against leukemia cell line HL-60 (TB) with GI50 of 5.15 µM, while compound 7a showed the highest sensitivity against ovarian cancer cell lines IGROV1 and OVCAR-4 with GI50 of 14.5 and 16.0 μM, respectively. In addition, compounds 3d and 7a showed TGI values of 72.2 and 96.3 µM, respectively against ovarian cancer cell line OVCAR-4. Furthermore, the target compounds were tested for antiviral activity against Herpes Simplex virus type-1 (HSV-1) using plaque reduction infectivity assay. The results indicated that compounds 3a-d and 7a exhibited very weak antiviral activity in comparison to Aphidicolin as a positive control.

Antioxidant and Cytotoxic Activity of Compounds from the Stem of Juncus effusus

The stems of Juncus effusus were extracted with 70% aqueous ethanol and the concentrated extract was partitioned with ethyl acetate, n-butanol and , successively. Two compounds were isolated from the ethyl acetate fraction through the repeated silica gel and Sephadex LH-20 column chromatographies. According to the results of physico-chemical and spectroscopic data including NMR and IR, the chemical structures of the compounds were determined as dehydroeffusol (1) and effusol (2). Dehydroeffusol and effusol exhibited potent scavenging activity for DPPH and ABTS radicals with the values as and in DPPH assay, and as and in ABTS assay, respectively. The compounds also significantly inhibited the proliferation of human cancer cell lines, AGS and A549.

Design of Novel Potent Antihyperlipidemic Agents with Antioxidant/Anti-inflammatory Properties: Exploiting Phenothiazine’s Strong Antioxidant Activity

Because atherosclerosis is an inflammatory process involving a series of pathological events such as dyslipidemia, oxidative stress, and blood clotting mechanisms, we hereby report the synthesis and evaluation of novel compounds in which antioxidant, anti-inflammatory, and squalene synthase (SQS) inhibitory/hypolipidemic activities are combined in simple molecules through design. The coupling of two different pharmacophores afforded compounds 1-12, whose biological profile was markedly improved compared to those of parent lead structures (i.e., the hypolipidemic 2-hydroxy-2-aryl-(benzo)oxa(or thia)zine and the antioxidant phenothiazine). Most derivatives strongly inhibited in vitro microsomal lipid and LDL peroxidation, exhibiting potent free-radical scavenging activity. They further significantly inhibited SQS activity and showed remarkable antidyslipidemic activity in vivo in animal models of acute and high-fat-induced hyperlipidemia. Finally, several compounds showed anti-inflammatory activity in vitro, inhibiting cycloxygenase (COX-1/2) activity. The multimodal properties of the new compounds and especially their combined antioxidant/SQS/COX inhibitory activity render them interesting lead compounds for further evaluation against atherosclerosis.

Antioxidant Response of Stevia rebaudiana B. to Polyethylene Glycol and Paclobutrazol Treatments Under In Vitro Culture

This investigation was carried out with the aim of determining the effect of paclobutrazol (PBZ) (0 and 2 mg l(-1)) and polyethylene glycol (PEG) (0, 2, 4 and 6 % w/v of PEG 6000) treatments on antioxidant system of Stevia rebaudiana Bertoni under in vitro condition. Analysis of data showed that PEG treatment significantly increased hydrogen peroxide (H2O2) and phenolic contents, while PBZ treatment limited the effect of PEG on them. Our data revealed that PEG treatment significantly increased total antioxidant capacity, catalase (CAT), ascorbate peroxidase (APX), polyphenol oxidase (PPO) and peroxidase (POD) activity, while it inversely decreased glutathione reductase (GR) activity. The superoxide dismutase (SOD) activity was not affected by PEG treatment. PBZ treatment induced significantly higher levels of CAT and GR activity and lower levels of SOD activity in PEG-treated plants. PBZ in combination with PEG resulted in no significant difference on APX activity with PEG treatment alone. PBZ treatment prevented the effect of PEG on the PPO activity. PEG (with or without PBZ) treatment increased the ascorbate pool, whereas total glutathione level was not affected by PEG. Our finding indicated that PBZ reduced the negative effect of PEG treatment by quenching H2O2 accumulation and increasing the CAT activity. Collectively, the antioxidant capacity of S. rebaudiana in PEG treatment condition was associated with active enzymatic and non-enzymatic defence systems which partly could be improved by the PBZ treatment. In addition, a higher accumulation of phenolic compounds leads to a more potent reactive oxygen species scavenging activity in S. rebaudiana.

Biological Properties of Iranian Hypericum Scabrum Essential oil and Hydroalcoholic Extract From Alamut Mountain

In this study, for the first time, the composition of the oil and hydroalcoholic extracts derived from Iranian Hypericum scabrum and also their antioxidant properties were considered. For this purpose, the seed essential oil was extracted by Clevenger apparatus following identification by GC-MS analysis. In equivalent, the total flavonoid content of the hydroalcoholic extract was measured spectrophotometrically. Then, the antioxidant activities of both extracts were measured by DPPH and β-carotene bleaching tests. The results indicated that α-pinene, spathulenol, β-pinene, α-cadinol, limonene and epi-α-muurolol are the major fractions in oil sample separated by GC-MS analysis. Also, the hydroalcoholic extract of H. scabrum possessed tolerable flavonoid content. In addition, both extracts overcame potent free-radical scavenging and antioxidant activities. These data may suggest the extracts derived from Iranian H. scabrum as a valid antioxidant source.