Lanthanide(III) complexes are more active inhibitors of the Fenton reaction than pure ligands

OBJECTIVES: This study is an extension to our finding of direct anti-oxidant activities of lanthanide(III) complexes with the heterocyclic compound, 5-aminoorotic acid (AOA). In this experiment, we used AOA and coumarin-3-carboxylic acid as the two heterocyclic compounds with anti-oxidant potential, to produce the complexes with different lanthanides. METHODS: Lanthanide(III) complexes were tested on the iron-driven Fenton reaction. The product of this reaction, the hydroxyl radical, was detected by HPLC. RESULTS: All complexes as well as their ligands had positive or neutral effect on the Fenton reaction but their behavior was different. Both pure ligands in low concentration ratio to iron were inefficient in contrast to some of their complexes. Complexes of neodymium, samarium, gadolinium, and partly of cerium blocked the Fenton reaction at very low ratios (in relation to iron) but the effect disappeared at higher ratios. In contrast, lanthanum complexes appeared to be the most promising. Both blocked the Fenton reaction in a dose-dependent manner. CONCLUSION: Lanthanide(III) complexes were proven to block the iron-driven production of the hydroxyl radical. Second, the lanthanide(III) element appears to be crucial for the anti-oxidant effect. Overall, lanthanum complexes may be promising direct anti-oxidants for future testing

IN-VITRO ANTIOXIDANT AND IN-VIVO HEPATO PROTECTIVE ACTIVITY OF ETHANOL EXTRACTS FROM THE BARK OF SHOREA ROBUSTA (DIPTEROCARPACEAE) AGAINST CARBON TETRA CHLORIDE INDUCED LIVER TOXICITY IN RATS

ABSTRACT: The study is designed for the evaluation of in-vivo Hepato protective and in-vitro Anti oxidant activity of ethanol extracts from the bark of Shorea robusta (Dipterocarpaceae) by CCl4 induced hepatotoxicity in rats. Ethanol extracts from the bark Shorea robusta (EESR) was evaluated for hepatoprotective activity in rats by inducing liver damage by CCl4. The anti oxidant activity of EESR was assayed by various in-vitro antioxidant methods and activities were compared to standard ascorbic acid. Ethanol extracts at an oral dose 200mg/kg and 400mg/kg exhibited a significant (*p<0.005) protective effects by lowering the level of SGOT, SGPT, ALP, Serum bilirubin, total cholesterol and increasing the level of total proteins as compared to Silymarin (50mg/kg) used as positive control. The extracts exhibit significant anti oxidant activity in various in vitro anti oxidant models.  From these studies we are concluding that, the ethanolic extracts of S.robusta have potent hepatoprotective effects and have anti oxidant properties, hence can be used as a natural product against liver damage.KEY WORDS: Anti oxidant, Carbon tetra chloride,  Hepatoprotective,  Shorea robust

Peptides Hydrolysate Derived from Collagen of Snakehead Murrel (Channa striata) Skin Demonstrate Anti-cholesterol and Anti-oxidant activities

Anti-cholesterol and anti-oxidant play a crucial role to combat cardiovascular disease (CVD), due to formation of arterial plagues from oxidation of cholesterol. In the past decades, bioactive peptides demonstrating anti-cholesterol and anti-oxidant activities have emerged as the alternative drugs. In this study, acid soluble collagen was extracted from the skin of snakehead murrel and employed to induce secretion of collagenase by Bacillus licheniformis F11.4. The collagenases secreted were in turn used to produce peptides hydrolysate and were grouped in two distinct collagenase fractions, designated as fraction D and F. Peptides hydrolysate produced by the fraction D was found to demonstrate HMG-CoA inhibitor activity comparable to pravastatin and limited anti-oxidant activity. Meanwhile, peptides hydrolysate generated using the fraction F demonstrated anti-oxidant activity comparable to BHT (2mM), vitamin C (2mM), and vitamin E (2mM), but limited HMG-CoA activity. Combination of the fraction D and F resulted in substantial HMG-CoA inhibition and anti-oxidant activities

CoQ10 and Aging.

The aging process includes impairment in mitochondrial function, a reduction in anti-oxidant activity, and an increase in oxidative stress, marked by an increase in reactive oxygen species (ROS) production. Oxidative damage to macromolecules including DNA and electron transport proteins likely increases ROS production resulting in further damage. This oxidative theory of cell aging is supported by the fact that diseases associated with the aging process are marked by increased oxidative stress. Coenzyme Q10 (CoQ10) levels fall with aging in the human but this is not seen in all species or all tissues. It is unknown whether lower CoQ10 levels have a part to play in aging and disease or whether it is an inconsequential cellular response to aging. Despite the current lay public interest in supplementing with CoQ10, there is currently not enough evidence to recommend CoQ10 supplementation as an anti-aging anti-oxidant therapy

Synthesis of quinazolinone derivatives containing an acyl hydrazone skeleton as potent anti-urease agents enzyme kinetic studies and anti-oxidant properties

This paper covers the synthesis, in vitro urease inhibition, enzyme kinetic parameters, and anti-oxidant studies of a novel series of quinazolinone derivatives containing an acyl hydrazone skeleton. Compounds 3a, 3b, 5a, and 5b, having IC50 values ranging from 1.86 +/- 0.07 to 6.38 +/- 0.11 mu g mL(-1), show greater inhibitory activity than the standard inhibitor, thiourea. Among the products, (2-[2-(3-methoxybenzyl)-4-oxoquinazolin-3(4H)-yl]acetohydrazide) proves to be the most potent, exhibiting enzyme inhibition activity with an IC50 value of 1.86 +/- 0.07 mu g mL(-1). Kinetic studies involving the Lineweaver-Burk plots reveal that the inhibition mechanism of the most active compounds (3a, 3b, 5a, and 5b) on urease activity are found to be in competitive mode. Also, the anti-oxidant activity and radical-scavenging properties of the synthesized compounds are evaluated using cupric reducing anti-oxidant activity, ferric reducing anti-oxidant capacity, 2,2 '-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid), and 2,2-diphenyl-1-picrylhydrazyl assays. Compounds 3a, b and 5a, b have good anti-oxidant properties and radical-scavenging activity at various final concentrations

Comparison of anti-oxidant activities of seventy herbs that have been used in Korean traditional medicine

Many herbs have been used as therapeutics in Korean traditional medicine. In view of their clinical indications, anti-oxidant activity may contribute to their pharmacological effects. However, anti-oxidant information on these plants has not been available. In this study, seventy herbs which have been used in Korean traditional medicine were selected and screened for anti-oxidant activity using their water extracts. The anti-oxidant activity was assessed by their ability to inhibit three oxidation reactions; luminol/Fenton reagent, 2, 7-dichlorodihydrofluorescein (DCHF)/Fenton reagent and DCHF/peroxynitrite. In each assay, 70 herbs were divided into two groups; anti-oxidant group which inhibited the respective oxidation reaction and was majority (about 60 herbs), and pro-oxidant group which enhanced the oxidation reaction but was minority (more or less 10 herbs). When the herbs were listed in the order of their anti-oxidant strength, the orders obtained from each assay were found to be quite similar. The upper top rankers (more or less 10 herbs) in each assay showed strong activity compared to the others. The uppermost rankers in each assay were Rubus coreanus Miquel/ Rubus schizostylus, Schisandra chinensis Baillon/ Schizandra chinensis and Terminalia chebula Retzius/ Terminalia chebula. Of the pro-oxidant herbs, about 4-5 herbs were strongly pro-oxidant, which enhanced the control oxidation reactions to 150-300%. But the meaning of this observation is not known since few of them in one assay were also anti-oxidant in other assays. The results obtained in the present study may serve as information for understanding pharmacological effects of these herbs and developing new drugs from them

Delaying spontaneous combustion of reactive coals through inhibition

A moist coal adiabatic oven test has been used to quantify the effect of applying an anti-oxidant agent to reactive coals from Australia and the US. For the dosage rate applied, the anti-oxidant significantly reduces the coal self-heating rate and extends the time taken to reach thermal runaway by a factor of three for sub-bituminous coal and by a factor of two for the same application to high volatile C bituminous coal. The laboratory result obtained for sub-bituminous coal from Powder River Basin is in direct agreement with the practical site experience of applying the anti-oxidant product as a spontaneous combustion management control. Consequently, it is now possible to benchmark the application of the anti-oxidant to any reactive coal prior to mining as part of developing a leading practice spontaneous combustion management plan

IN VITRO ANTI OXIDANT ACTIVITY OF CHROMATOGRAPHICALLY SEPARATED FRACTIONS FROM THE LEAVES OF AGERATUM CONYZOIDES L

Synthetic anti oxidants are not safe for human health. It is often claimed that they may develop carcinoma in human body. Therefore, search for natural anti oxidants was going on and extended up to plant sources. Many medicinal plants are known having anti oxidant activity. Aageratum conyzoides Linn. is one such plant. In order to isolate anti oxidant compound (s) from the leaves of A. conyzoides L. the present study was undertaken. In isolation study silica gel G column chromatography of the powdered leaves of A.conyzoides L. was done when six fractions were separated. In vitro anti oxidant activity of these six fractions was measured by superoxide anion generation with help of xanthine-xanthine oxidase assay and with linoleic acid peroxidation assay as well as DPPH photometric assay. Results showed that fourth fraction had maximum anti oxidant activity. Inhibitory activities of xanthine oxidation, linoleic acid peroxidation and scavenging capacity of DPPH by the fourth fraction were respectively 96%, 97% and 96% whereas for other five fractions inhibitory activities were quite low. Anti oxidant activity is known to be associated with compounds like total phenol, flavonoids, ascorbic acid and carotenoids. These compounds were estimated in the separated six fractions after chromatography of powdered leaves of A. conyzoides L. Results showed that fourth fraction had total phenol, flavonoids, ascorbic acid and carotenoids in the concentrations of 58 mg/mg dry wt, 88 mg/mg dry wt, 22 mg/g dry wt and 25 mg/g dry wt respectively. The amounts were significantly higher in comparison to that of other fractions. In vitro anti oxidant activity of the fourth fraction was, therefore, related with high amounts of total phenol, flavonoids, ascorbic acid and carotenoids. Present study indicated that the separated fourth fraction after silica gel G column chromatography of powdered leaves of A.conyzoides L. may be used as natural anti oxidant

Chemical composition and anti-diabetic properties of Cytisus multiflorus

Bakground and aims: The interest on plants with potential medicinal properties has been increasing worldwide. In the Iberian Peninsula there are some endemic species known by the population for their pharmacologic activity with valorization potential that have not been yet characterized. The white Spanish broom (Cytisus multiflorus) is described as having anti-diabetic effect [1] and in a preliminary the hypoglycemic and hyper-insulinemic effect of an aqueous extract has been shown [2]. The aim of this work was to fractionate and analyse the composition of the aqueous extract of C. multiflorus flowering parts and evaluate its potential as an anti-diabetic agent. Materials and methods: The aqueous extract was primarily fractionated by SPE using water:methanol (W:Me) eluent (a 10% step-wise gradient W:Me from 100:0 to 0:100) followed by high performance liquid chromatography with diode array detector (HPLC-DAD). The most relevant fraction were analysed by LC-MS to determine the chemical composition. Total fenol content was determined by a modified Folin-Ciocalteau method and the anti-oxidant activity was evaluated by the DPPH mehod. Finally, the hipoglicemic potential was evaluated in vivo using glucose intolerant rats (GIR). Results: Eleven fractions of the bulk extract were obtained. Seven of these fractions (10, 30, 40, 50, 60, 70 e 80% Me) were found to have a relevant compounds, mostly flavonoid compounds, namely, rutin (50, 60 and 70% Me fractions), ferrulic acid (30% Me), referred as having hypoglicemic effect. The fractions obtained with 50 and 70% Me showed the highest content in phenol equivalents and the highest anti-oxidant effect were found in the 50 and 60% Me fractions. The 30 and 60% Me fraction had no effect on the post-prandial glicemia. Conclusions: The 30, 50, 60 and 70% Me fractions, due to their chemical composition and anti-oxidant effects were the most promising to have anti-diabetic effect. However, the 30 and 60% Me were found to be ineffective. The 50% Me fraction showed both a high content of flavonoid compounds and the highest anti-oxidant power which suggest that it may constitute the most promising one. The anti-diabetic properties of this fraction should be investigated. [1] Camejo-Rodrigues J. et al. (2003). J. Ethnopharmacol, 89, 199-209 [2] Célia M. Antunes, Laurinda R. Areias, Inês P. Vieira, Ana C. Costa, M. Teresa Tinoco, & Júlio Cruz-Morais (2009). Rev. Fitoterapia 9 (Supl.1): 91

SCREENING OF ANTI-OXIDANT ACTIVITY OF METHANOLIC EXTRACT OF GRACILARIA FERGUSONII J.AG. (RED SEAWEED) IN HARE ISLAND, THOOTHUKUDI, TAMIL NADU, INDIA

In the present study, anti-oxidant activity of methanol extract of Gracilaria fergusonii J.Ag. collected from Hare Island, Thoothukudi in the south east coast of Tamil Nadu, India was screened. Free radical scavenging activity was evaluated using 1,1-diphenyl-2-picryl hydrazyl (DPPH) free radical and a reducing power by Cupric Reducing Antioxidant Capacity (CUPRAC) assay. The percentage of scavenging activity of DPPH by methanol extract at 100μg, 200μg, 300μg, 400μg and 500μg were 31.35, 45.23, 61.76, 79.54 and 82.93% respectively. At a concentration of 100μg, 200μg, 300μg, 400μg and 500μg of methanol extract, the absorbance were 0.295, 0.302, 0.328, 0.367 and 0.384 respectively. These results similar to those obtained from the DPPH assay in which 500μg showed the highest total anti-oxidant capacity, followed by 400μg, 300μg and 200μg, and lastly 100μg. The results showed that both DPPH scavenging activity and absorbance were increased when the concentration of methanol extract was also increased. Vitamin C, a strong anti-oxidant was also used as control, and the anti-oxidant potential was compared to all tested samples. Keywords: Seaweeds, Gracilaria fergusonii, anti-oxidant, methanolic extract, Hare Island