Hydrogen Peroxide Radical Scavenging Activity Research Articles

In vitro Antioxidative Profiling of Different Fractions of Dendrocalamus strictus (Roxb.) Nees leaf Extracts

Introduction: Plant derived natural antioxidants have attracted scientists for many years because of their economic viability and virtually no side effects. Therefore the present study was planned to evaluate the antioxidant activity of the leaf of Dendrocalamus strictus (Roxb.) Nees, used as household therapy for cold, cough and fever, extracted with different solvents of increasing and decreasing polarity such as water (DAQE), acetone (DAE) and methanol (DME). Methods: The antioxidant profiling of the leaf extracts was done at varying concentrations (20-200 μg/ml), using different assays like 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity, reducing power assay and hydrogen peroxide radical scavenging activity along with their total phenolic and flavonoid contents. Results: DME had more antioxidant activity than other extracts. Total phenol and flavonoid content were highest in the DAQE and DME fraction (112.10 ± 11.21 mg GAE/g and 199.20 ± 19.92 mg QE/g) respectively. This result also suggests a close relationship among total phenolic content, flavonoids and antioxidant activity. Conclusion: The study shows that leaf of Dendrocalamus strictus is a potential source of useful natural antioxidants, which substantiates its use as herbal remedies.

Carbon tetrachloride induced kidney and lung tissue damages and antioxidant activities of the aqueous rhizome extract of Podophyllum hexandrum

BackgroundThe present study was conducted to evaluate the in vitro and in vivo antioxidant properties of aqueous extract of Podophyllum hexandrum. The antioxidant potential of the plant extract under in vitro situations was evaluated by using two separate methods, inhibition of superoxide radical and hydrogen peroxide radical. Carbon tetrachloride (CCl4) is a well known toxicant and exposure to this chemical is known to induce oxidative stress and causes tissue damage by the formation of free radicals.Methods36 albino rats were divided into six groups of 6 animals each, all animals were allowed food and water ad libitum. Group I (control) was given olive oil, while the rest groups were injected intraperitoneally with a single dose of CCl4 (1 ml/kg) as a 50% (v/v) solution in olive oil. Group II received CCl4 only. Group III animals received vitamin E at a concentration of 50 mg/kg body weight and animals of groups IV, V and VI were given extract of Podophyllum hexandrum at concentration dose of 20, 30 and 50 mg/kg body weight. Antioxidant status in both kidney and lung tissues were estimated by determining the activities of antioxidative enzymes, glutathione reductase (GR), glutathione peroxidase (GPX), glutathione-S-transferase (GST) and superoxide dismutase (SOD); as well as by determining the levels of reduced glutathione (GSH) and thiobarbituric acid reactive substances (TBARS). In addition, superoxide and hydrogen peroxide radical scavenging activity of the extract was also determined.ResultsResults showed that the extract possessed strong superoxide and hydrogen peroxide radical scavenging activity comparable to that of known antioxidant butylated hydroxy toluene (BHT). Our results also showed that CCl4 caused a marked increase in TBARS levels whereas GSH, SOD, GR, GPX and GST levels were decreased in kidney and lung tissue homogenates of CCl4 treated rats. Aqueous extract of Podophyllum hexandrum successfully prevented the alterations of these effects in the experimental animals.ConclusionOur study demonstrated that the aqueous extract of Podophyllum hexandrum could protect the kidney and lung tissue against CCl4 induced oxidative stress probably by increasing antioxidant defense activities.

Antioxidant and protective effect of ethyl acetate extract of podophyllum hexandrum rhizome on carbon tetrachloride induced rat liver injury.

The antioxidant and hepatoprotective activities of ethyl acetate extract was carefully investigated by the methods of DPPH radical scavenging activity, Hydroxyl radical scavenging activity, Superoxide radical scavenging activity, Hydrogen peroxide radical scavenging activity and its Reducing power ability. All these in vitro antioxidant activities were concentration dependent which were compared with standard antioxidants such as BHT, α-tocopherol. The hepatoprotective potential of Podophyllum hexandrum extract was also evaluated in male Wistar rats against carbon tetrachloride (CCl4)-induced liver damage. Pre-treated rats were given ethyl acetate extract at 20, 30 and 50 mg/kg dose prior to CCl4 administration (1 ml/kg, 1:1 in olive oil). Rats pre-treated with Podophyllum hexandrum extract remarkably prevented the elevation of serum AST, ALT, LDH and liver lipid peroxides in CCl4-treated rats. Hepatic glutathione levels were significantly increased by the treatment with the extract in all the experimental groups. The extract at the tested doses also restored the levels of liver homogenate enzymes (glutathione peroxidase, glutathione reductase, superoxide dismutase and glutathione-S- transferase) significantly. This study suggests that ethyl acetate extract of P. hexandrum has a liver protective effect against CCl4-induced hepatotoxicity and possess in vitro antioxidant activities.

Synthesis and evaluation of antioxidant activities of some indole-2,3-dione derivatives and analogs

In the present study, a series of novel Schiff bases of isatin were synthesized by condensation of imesatin with different aromatic aldehydes. The imesatins were synthesized by reaction of isatin with p-phenylenediamine. The chemical structures of the synthesized compounds were confirmed by means of IR, 1H-NMR, 13C-NMR, mass spectroscopy, and elemental analysis. These compounds were screened for antioxidant activity by DPPH, nitric oxide and hydrogen peroxide radical scavenging activity. In all the methods, the compound 3-(4-(3,4,5-trimethoxy benzylideneamino)phenylimino) indoline-2-one (5d) showed highest antioxidant activity because of the presence of electron donating groups and the compound 3-(4-(4-nitrobenzylideneamino)phenylimino) indoline-2-one (5f) showed the least activity because of the presence of an electron withdrawing group.

하이아미의 정조 및 현미 추출물의 in vitro 항산화 및 항암활성

하이아미의 정조와 현미상태에 대해 일품벼를 대조구로 하여 항산화성분의 함량과 에탄올 추출물에 대한 in vitro 항산화활성 및 항암활성을 측정하였다. 하이아미의 정조 및 현미 추출물의 총 폴리페놀 함량은 각각 6.31 및 3.75 ㎎/g 으로 나타났으며, 일품은 각각 5.66 및 3.47 ㎎/g으로 나타나 하이아미가 약간 높은 것을 알 수 있었다. 하이아미의 정조와 현미 추출물의 γ-oryzanol 함량은 각각 33.53 및 39.47 ㎎/100 g으로 나타났으며, 일품의 경우 각각 24.33 및 28.68 ㎎/100 g으로 나타나 일품에 비해 하이아미에서 높은 함량을 보이는 것으로 나타났다. 하이아미와 일품벼 정조 및 현미의 70% 에탄올 추출물에 대한 DPPH radical, hydrogen peroxide, superoxide radical 및 hydroxyl radical 소거활성을 5 ㎎/㎖의 농도에서 측정한 결과 하이아미가 일품에 비해 높은 것으로 나타났으며, 정조 추출물이 현미 추출물보다 높은 radical 소거활성을 보이는 것으로 나타났다. 70% 에탄올 추출물에 대한 in vitro 항암활성을 측정한 결과 정조 및 현미 추출물의 억제 활성은 용량 의존적으로 증가하는 것으로 나타났으며, 특히 하이아미는 위암 및 유방암세포에 높은 활성을 보였으며, 일품은 대장암 및 간암세포에 대해 높은 활성을 보였다.

Mangrove Plant Extracts: Radical Scavenging Activity and the Battle against Food-Borne Pathogens

Aims: The present study was carried out to evaluate the radical scavenging and antibacterial activity of methanolic leaf extracts of mangrove plants. 8 mangrove plants, which are used as folk medicine in various tropical countries, were collected in Pichavaram and Thondi, Tamil Nadu, India. Methods: The antioxidant properties of methanolic leaf extracts were assessed under in vitro conditions using different antioxidant tests, including DPPH, nitric oxide, hydrogen peroxide, hydroxyl radical scavenging assay, reducing power, ferrous ion chelating, and lipid peroxidation inhibition assay. Results and Conclusion: Of the 8 mangrove plants screened, Rhizophora mucronata (100 μg/ml) showed significantly higher (p < 0.05) activities for all antioxidant assays, and its IC50 values were 43.17, 116, 60.06, and 46.76 μg/ml for DPPH, hydrogen peroxide, nitric oxide, and hydroxyl radical scavenging activity, respectively. Butylated hydroxytoluene, ascorbic acid and α-tocopherol were used as positive controls. Methanolic extracts of R. mucronata were also found to be effective in protecting plasmid DNA against the strand breakage induced by hydroxyl radicals in a Fenton’s reaction mixture. Moreover, the total phenolic content of R. mucronata (720.79 mg/gm of dry leaves) was very high and a strong positive correlation was observed between its phenolic content and its antioxidant activity. Methanolic leaf extracts of mangrove plants exhibited no antibacterial activity against seven food-borne pathogens studied.

Antioxidant Activity of Talinum portulacifolium (Forssk) Leaf Extracts

SUMMARY The aim of the study is to investigate the antioxidant activity through, reducing power, 2, 2diphenyl-1-picryl hydrazyl radical (DPPH), nitric oxide radical (NO), superoxide radical, hydrogen peroxide radical (H O ) scavenging activity and the amount of total phenolic compounds of chloroform, ethyl acetate, methanol and aqueous extracts of the leaves of Talinum portulacifolium. Chloroform extract of leaves of T. portulacifolium showed highest antioxidant activity, with a direct relationship between activity and concentration of extracts (15 - 240 µg/mL). Among all the extracts, the highest amount of the total polyphenolic compounds was found in the chloroform extract. Chloroform extract of T. portulacifolium showed an important free radical scavenging activity towards the DPPH, NO, Superoxide and H O radicals, with IC values of 133.26, 165.75, 156.34 and 135.29 µg/mL, respectively. In the lipid peroxidation assay, extracts of chloroform and ethyl acetate showed a remarkable inhibitory activity. The extracts showed significant activity in all the experiments but lower than the standard antioxidant, ascorbic acid.

Some Physiological Activities Observed from Ethanol Extracts of Germinated Specialty Rough Rice

This study analyzed the some of the physiological activities of 70% ethanol extracts of specialty rough rice (‘Goami2’, ‘Keunnunbyeo’, and ‘Heugkwangbyeo’ rough rice cultivars) before and after germination. The physiological activities of the extracts were analyzed for their inhibition of linoleic acid peroxidation, hydrogen peroxide radical scavenging activity, superoxide dismutase-like activity, xanthine oxidase inhibitory activity, and nitrite scavenging effects. The most active rough rice cultivar was ‘Heugkwangbyeo’ and germinated ‘Heugkwangbyeo’ rough rice was more effective than ungerminated rough rice, having higher inhibition activity of linoleic acid peroxidation (1.2-fold), hydrogen peroxide radical scavenging activity (1.4-fold), superoxide dismutase-like activity (1.2-fold), and xanthine oxidase inhibitory activity (1.1-fold). The nitrite scavenging effect was increased after germination (2.1-fold) and decreased as pH increased. According to the results obtained in this study, 70% ethanol extracts from germinated ‘Heugkwangbyeo’ rough rice can be used for industrial applications such as the functional food materials.

Antioxidant and Hepatoprotective Activities of Elephantopus tomentosus. Ethanol Extract

The current study evaluated the antioxidant and hepatoprotective activities of Elephantopus tomentosus. L. (Asteraceae) ethanol extract (ET). In the experiment, total antioxidant capacity, reducing capacity, DPPH* and hydrogen peroxide scavenging, and Fe3 +-induced lipid peroxidation inhibiting activities of ET were determined. The results indicated that ET exhibited antioxidant (1 mg/mL ET was equal to 2.1 mM TEAC), lipid peroxidation inhibition, hydrogen peroxide, and free radical scavenging activities. The hepatoprotective activity of ET was studied using CCl4-induced liver toxicity in rats. Oral administration of ET (500 mg/kg) significantly reduced CCl4-induced hepatotoxicity in rats, as observed from the serum level of the liver enzyme aspartate aminotransferase (AST), alanine aminotransferase (ALT), and also from the histopathologic study. The total phenolic content in the lyophilized ethanol extract is approximately 10%. The results of the current study indicated that the hepatoprotective effect of E. tomentosus. might be ascribable to its antioxidant and free radical scavenging properties.

Antioxidant activity of cherry laurel fruit ( Laurocerasus officinalis Roem.) and its concentrated juice

Cherry laurel fruit and its concentrated juice (pekmez) were examined for their antioxidant activities using different free-radical scavenging activity tests [hydrogen peroxide, superoxide radical, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical], together with reducing power and inhibition of oxidation of human low-density lipoprotein cholesterol. On a fresh weight basis, pekmez exhibited a significantly ( P < 0.01) higher antioxidant activity than that of cherry laurel fruit in most cases. However, on a dry weight basis hydrogen peroxide and DPPH radical scavenging activities, and reducing power were significantly higher ( P < 0.01) in cherry laurel fruit than in its pekmez, with some exceptions, thus indicating possible destruction of antioxidative compounds during pekmez production. This was also partly due to the moisture content of these two samples. On the basis of the results presented, it is suggested that the intake of cherry laurel fruit and pekmez rich in phenolics would have beneficial effects in improving amelioration of degenerative diseases caused by oxidative stress. Therefore, both cherry laurel fruit and pekmez might be considered as functional food ingredients and nutraceuticals.