Total Scavenging Research Articles

Redox properties of Abarema cochliacarpos (Gomes) Barneby & Grime (Fabaceae) stem bark ethanol extract and fractions

The redox properties of the hydroethanol extract (EE) and its ethyl acetate (EAF) and hydromethanol (HMF) fractions obtained from Abarema cochliacarpos (Gomes) Barneby & Grimes stem bark were evaluated. EAF had the highest total phenol content (848.62 ± 78.18 mg g−1), while EE showed the highest content of catechin (71.2 µg g−1). EE, EAF and HMF exhibited the highest levels of antioxidant activity at 100 and 1000 µg mL−1 when the non-enzymatic antioxidant potential was evaluated by the total reactive antioxidant potential, total antioxidant reactivity and nitric oxide scavenging assays. In addition, EAF and HMF showed SOD-like activity. The results for EE, EAF and HMF in this study showed that A. cochliacarpos (Gomes) Barneby & Grimes stem bark have redox properties and may be able to help the endogenous enzymatic and non-enzymatic systems to keep the redox balance.

Effect of 1-MCP on Bioavailability of Lingwu Long Jujube <i>In Vitro</i> Digestion

The present study investigated the effect of 1-MCP on bioavailability of Lingwu long jujube stored at 0 °C for 60 days. At the end of the storage, compared with the control samples, Lingwu long jujube treated with 1-MCP exhibited higher Vc bioaccessibility, total phenolic content and free radical scavenging capacity, which demonstrated that 1-MCP treatment could provide a better effect on maintaining the bioavailability of Lingwu long jujube.

HPLC–MS analyses and bioactivities of novel chemicals in Devil’s club (Oplopanax horridus (Sm.) Miq.)

Abstract Devil’s club (Oplopanax horridus (Sm.) Miq.) has traditionally been used as a folk medicine by native North Americans for the treatment of various chronic diseases. A methanolic extract and its sub-fractions by liquid–liquid re-extraction, i.e., chloroform (CHCl3), ethyl acetate (EtOAc), n-butanol (BuOH), and water fractions, were analysed by their anti-cancer activity with in vitro cell proliferative bioassays, and their antioxidant capacities in terms of the determination of total phenolic content (TPC), ORAC value, and DPPH free radical scavenging activity. The whole extract of the dried root contained high TPC and possessed strong ORAC and DPPH radical scavenging activities. In addition, the extract exhibited a strong anti-proliferative ability against HT-29 cancer cells, e.g., with an inhibitive rate of 56.5% with a 0.2-mg/mL extract. Further investigation by HPLC–UV–MS identified significant bioactive phenolic compounds in the chloroform fraction, including gallic acid, caffeic acid, 4-O-feruloylquinic acid, 5-O-feruloylquinic acid, ferulic acid, methyl feruloylquinate, methyl ferulate, and quercetin. These results suggested that the associated bioactivity of the plant might result from the contribution of phenolic compounds.

A comparative study on antioxidant activity of water and ethanol extracts of ten Chinese herbs

A search of naturally occurring antioxidant compounds from plant sources might provide leads for the development of novel drugs, which may reduce the risk of chronic diseases caused by free radicals. An antioxidant activity and total phenolic content of the water and alcohol extracts of 10 herbs from local pharmacy were studied. The highest phenolic content of the water and alcohol extracts of BSR was found with 36.70 and 91.17 mg PE /g. The flavonoid compounds were found to have the highest content of BSR with 15.58 mg RE for WE. In vitro, the radical-binding activity with DPPH (1,1-dip-henyl-2-picrylhydrazyl radical) and total antioxidant power (Ferric reducing/antioxidant power, FRAP) of ten herbs extracts were determined. At 1.0 mg/ml concentration of herbs, CI and BSR exhibited the good reducing capacity of 0.762 and 0.650. The high correlation values between total phenolic content (TPC) and scavenging efficiency (SE) suggest that the major antioxidant compounds in studied ten herbs might be phenolic compounds. Key words: DPPH radical, antioxidant activity, ferric reducing/antioxidant power (FRAP), Chinese herbs.

Comparative Evaluation of a Modified Acetic Method for Extraction of Antioxidant Compounds from Black Beans (<i>Phaseolus vulgaris</i>)

Extraction of phenolic compounds from bean seed coats by acetic acid was evaluated and compared to conventional extraction with 80% methanol. Total phenols, flavonoids and free radical scavenging capacity were determined by colorimetric methods. Furthermore, qualitative flavonoid characterization was performed via HPLC diode array. The acetic acid extract contained 73.4 ± 7 mg/g of sample expressed as gallic acid equivalents (GAE), and 41.3 ± 4 mg/g as catechin equivalents (CE). The acetic acid extract (at 1 mg/mL) showed over 89% efficiency to scavenge the 1,1 diphenyl-2-picrylhydrazil (DPPH) radical (EC50 = 6.13 mg extract/mg standard). Gallic acid, delphinidin-3-glycoside, petunidinglycoside, petunidin, malvidin-3-glycoside, myricetin-glycoside, quercitin-glycoside, saponin (β-g), and 3-hydroxy-5, 7-megastigmadien-9-one were identified in both extracts. Additionally, kaempferol-3-glycoside was found in the acetic acid extract. Sequential acetic acid extractions indicated that the antiradical activity was about 90% in DPPH radical scavenging within the first 8 h of extraction, when compared to a 24 h extraction. In general, acetic acid offered a faster and more efficient approach for the extraction of phenolic

Study of chemical forms of heavy metals collected from the sediments of tin mining catchment

The chemical speciation of heavy metals (arsenic, chromium, copper, lead, zinc and tin) in the sediments of the former tin mining catchment Bestari Jaya, Peninsular Malaysia was determined using the latest version of the Community Bureau of Reference, the BCR 3-step, sequential extraction procedure. A fourth step was introduced for the digestion and analysis of the residue. The analysis of total metal content was carried out using microwave-assisted acid digestion. The percentage of each metal obtained from the four steps extraction (acid-soluble + reducible + oxidisable + residual) is in good agreement with the percentage of total metal content obtained from microwave digestion, which implies that the accuracy of the procedure. The degree of pollution in catchment sediments was assessed using geoaccumulation index Igeo and pollution intensity IPOLL. The results indicates that: (1) the sediments have been polluted with arsenic (8.8%), chromium (12.9%), copper (17.4%), lead (19.5%), zinc (14.9%) and tin (33.8%) and have high anthropogenic influences; (2) the calculation of geo-accumulation index suggests that catchment sediments have background concentrations of all the studied metals (Igeo < 0); (3) high I POLL, showed that all of these heavy metals pose a high environmental risk; and (4) the mobility order of metals in sediments at S1 and S2 was Sn>Pb>Zn>Cr >Cu >As, whereas at S3, S4 and S5 it was Cu>Pb>Zn>Cr>Sn>As. In conclusion, acidic pH, total organic carbon, scavenging ability and co-precipitation (inclusion, occlusion and adsorption) of studied metals with non-metals could account for changes in the geochemistry of the catchment sediments.

Radical scavenging-linked antioxidant activities of commonly used herbs and spices in Korea

Herbs and spices not only variety and racy flavour to Korean foods, they also are the richest source for antioxidant power. The present study evaluates the radical scavenging-linked antioxidant activities of hot water extracts from commonly used herbs and spices in Korea. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical and superoxide anion scavenging activities of bay extract were 39.5% and 22.1%, respectively. The hydroxyl radical scavenging activity was in order of dill (50.0%) > bay (31.3%) > garlic (27.9%) > white pepper and black pepper (15.1–15.3%) > onion (10.1%) extracts. Bay extract had the highest total phenolic content (17.86 μg CE/g). High correlation coefficients were found between the total phenol content and DPPH radical scavenging activity (R = 0.9162). These results indicate that herbs and spices had high antioxidant activity that is partly due to the phenolic compounds and provide basic data for further development of processed food products.

Erythrophleum africanum Afzel. (Caesalpiniaceae), an African toothpick: Phytochemical screening, total flavonoid content and antioxidant activity

Erythrophleum africanum is an endangered West African medicinal plant because of the large-scale use of its stems as toothpicks. Phytochemical screening (preliminary test and thin layer chromatography (TLC) method), a quantitative analysis of total flavonoids, anthocyanidins and radical scavenging activity (2,2’-diphenyl-1-picrylhydrazyl (DPPH) method) of stems of E. africanum were undertaken. The study shows that the quantification of the phenolic compounds (flavonic aglycones and anthocyanidins) and the assessment of the antioxidant activity put in evidence that in spite of the weak percentage (0.05%) of total flavonoids in the stem of E. africanum, the flavonoids are responsible to 94.46% of its antioxidant propriety. Key words: Erythrophleum africanum, total flavonoids, toothpick, antioxidant activity, 2,2’-diphenyl-1-picrylhydrazyl (DPPH).

Antioxidant Properties of Cashew Apple Wine (CAW)

In this study, total polyphenols content (TPC) and ascorbic acid content (AAC) in CAW were quantified. Total antioxidant activity, reducing capacity, and free radical scavenging activity of CAW were assayed. The TPC and AAC were 160 mg GAE /100ml and 132 mg/100 ml，respectivity. CAW exhibited effective antioxidant activities in the employed in vitro experiments, including total antioxidant activity, reducing capacity, and free radical scavenging activity, which indicates that phenolic compounds and ascorbic acid may play a key role in the antioxidant function of CAW.

Total phenolic contents and free radical scavenging activities of different extracts of seabuckthorn (Hippophae rhamnoides) pomace without seeds

In this study, 100% methanolic extract (ME), 70% aqua-methanolic extract (AME) and 100% aqueous extract of seabuckthorn byproduct were used to evaluate antioxidant activity. The total phenolic contents were high in AME (84.28 ± 1.58 mg of Gallic Acid Equivalent (GAE)/gm of extract) compared to other extracts. All the extracts scavenged different in vitro radicals in a concentration-dependent manner. The IC50 values were lowest in AME for 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, 2,2-diphenyl-1-picrylhydrazyl, superoxide and nitric oxide radicals, while ME had lowest values for hydroxyl radicals. The reducing power of the extracts increased in a dose-dependent manner and was highest in AME. The findings of this study revealed that seabuckthorn pomace without seed is one of the important resources as an antioxidant for food, pharmaceuticals, cosmetic or nutraceutical industries.

Total phenolic content, flavonoids and Superoxide radical scavenging activity of some Citrus peels

Total phenolic content, flavonoids and Superoxide radical scavenging activity of some Citrus peels

Antioxidant activity and chemical composition of Sideritis libanotica Labill. ssp. linearis (Bentham) Borm. (Lamiaceae)

Sideritis libanotica ssp. linearis was screened for the isolation of new natural antioxidant compounds. The antioxidant activity of flavones obtained from the methanol extract of the plant was evaluated in vitro using total antioxidant, reduction power and free radical scavenging activity. Results were compared with the positive controls of antioxidant standards (α-tocopherol and butylated hydroxytoluene). The results indicate that the flavones possess a higher antioxidant activity when compared to the other components in the plant. The lowest antioxidant activity was observed in fatty acids (FAs) and hydrocarbons. The FAs were methylated with MeOH and KOH and analysed by GC–MS. The structures of the isolated compounds were established based on spectroscopic evidence (NMR, GC–MS, HPLC, IR and UV). In this work, the isolated pure flavone (3′-O-methylhypolaetin 7-O-[6″′-O-acetyl-β-D-allopyranosyl-(1 → 2)]-6″-O-acetyl-β-D-glucopyranoside) was found to possess the highest antioxidant activity.

The effect of selegiline on total scavenger capacity and liver fat content: a preliminary study in an animal model

Selegiline is a selective irreversible inhibitor of the B-type of monoamine oxidase (MAO-B). The spectrum of its pharmacological activity is wide, possesses antioxidant, antiapoptotic and neuroprotective properties and, additionally, we found it is effective on the total scavenger capacity (TSC), and the regulation of fat content in rat liver kept on lipid-rich diet. Our aim was to clarify whether the oral treatment with selegiline is protective on oxidative damage of Sprague-Dawley adult rats in vivo. Four groups of rats (five animals in a group) were examined: (1) lipid-rich diet, (2) normal rat food, (3) lipid-rich diet+selegiline and (4) normal rat food+selegiline. Selegiline solution (2.5µg/ml) was supplied with the drinking water, which was freely available for the animals. Regarding the drinking habit of the rats (20-30ml/day), the daily dose was roughly equal with that used in the human therapy (5-10mg/day). TSC was determined both at the beginning (0day) and at the end of the study (28days), when the blood samples were taken for chemiluminometric assay. Fat content of the liver was determined in the freshly frozen tissue by Sudan staining. TSC was increased in both the selegiline-treated groups. Selegiline treatment prevented the increase of liver fat in the group fed with lipid-rich diet. Our results led us to the conclusion that prolonged selegiline administration can raise the antioxidant capacity of the animals and prevents the accumulation of fat in their livers.

Wet deposition and scavenging efficiency of gaseous and particulate phase polycyclic aromatic compounds at a central European suburban site

Abstract The concentration of 15 3–6-ring polycyclic aromatic hydrocarbons (PAHs) in atmospheric precipitation was monitored over 18 months in the years 2006–2008, using an automatic wet-only sampler at a suburban site in Brno, Czech Republic. The PAH concentration in rainwater varied between 2.8 and 571 ng L−1 and the volume weighted mean was 93 ng L−1 with fluoranthene, pyrene, phenanthrene and benzo(b)fluoranthene contributing most. The contribution of particle-associated PAH (sum of 15) to the wet deposition flux was by average 51%, 82% in summer and 47% in winter. The median total (gas and particulate) scavenging ratios, Wt (m3 L−1), varied between 450 for acenaphthene and 3.1 × 104 for fluoranthene. Estimates of the scavenged fraction in the column of air subject to precipitation suggest that typically only a few percent or less of the airborne PAHs are washed out during a precipitation event. The contribution of particle scavenging to total PAH scavenging varied between 7 and 98% among events. Its median was 41%. Scavenging efficiency seems to be influenced by mass size distribution. It is concluded that wet deposition of PAHs is less efficient than dry deposition.

The influence of low temperature on photosynthesis and antioxidant enzymes in sensitive banana and tolerant plantain (Musa sp.) cultivars

Low temperature (LT) is one of the major factors that limit crop production and reduce yield. To better understand the cold-tolerance mechanism in the plantains, a sensitive cultivar Williams (Musa acuminata AAA cv. Williams) and a tolerant cultivar Cachaco (Musa paradisiaca ABB cv. Dajiao) were used. LT resulted in increased malondialdehyde (MDA) content, elevated contents of hydrogen peroxide (H2O2) and superoxide radical (O2.-), and decreased photochemical efficiency (Fv/Fm) and net photosynthetic rate (P N), but cv. Cachaco showed better LT tolerance than cv. Williams. After LT treatment for 120 h, total scavenging capability (DPPH. scavenging capability) in Williams showed a significant decrease but no significant alternations was found in Cachaco. Ascorbate peroxidase (APX) and peroxidase (POD) displayed a significant increase but superoxide dismutase (SOD) showed no significant alternations and catalase (CAT) showed a significant decrease in Cachaco after 120 h of LT treatment. All the four antioxidant enzymes above showed a significant decrease in Williams after 120 h of LT treatment. Our results suggest that higher activities of APX, POD, SOD, and DPPH. scavenging capability to a certain extent can be used to explain the higher cold tolerance in the plantain, which would provide a theoretical guidance for bananas production and screening cold-resistant variety.

The influence of the atmosphere-snow-ice-ocean interactions on the levels of hexachlorocyclohexanes in the Arctic cryosphere

[1] The α- and γ-hexachlorocyclohexanes (HCHs) are being scavenged from the atmosphere by falling snow, with the average total scavenging ratios (WT) of 3.8 × 104 and 9.6 × 103, respectively. After deposition, HCH snow concentrations can decrease by 40% because of snowpack ventilation and increase by 50% because of upward migration of brine from the ice. HCH vertical distribution in sufficiently cold winter sea ice, which maintains brine volume fractions <5%, reflects the ice growth history. Initially, the entrapment of brine (and HCHs) in ice depends on the rates of ice growth and desalination. However, after approximately the first week of ice formation, ice growth rate becomes dominant. Deviations of HCH concentrations from the values predicted by the ice bulk salinity (rate of brine entrapment) can be explained by spatial variability of HCHs in surface water. HCH burden in the majority of the ice column remains locked throughout most of the season until the early spring when snow meltwater percolates into the ice, delivering HCHs to the upper ocean via desalination by flushing. Percolation can lead to an increase in α- and γ-HCH in the sea ice by up to 2%–18% and 4%–32%, respectively.

Tempol attenuates cocaine-induced death of PC12 cells through decreased oxidative damage

The association between cocaine administration and induction of oxidative stress in different brain regions suggests that oxidative damage is an important factor participating in cocaine disruption of normal central nervous system functions. In order to deal with this topic, brain penetrating exogenous antioxidants were suggested as a tool to prevent cocaine-induced oxidative damage and behavioral changes. Lately, we have shown that Tempol, a stable nitroxide radical reduced oxidative damage and attenuated the development and expression of cocaine psychomotor sensitization. To examine whether nitroxides, represented by Tempol, can exhibit protective effects against cocaine-induced cell death and to elucidate the molecular mechanism of cocaine-induced oxidative damage, we used the well established PC12 cell line model. The results showed that (1) cocaine induced cell death in a dose-dependent manner (2) and that it was reduced significantly by the stable nitroxide radical Tempol. Furthermore, (3) Tempol significantly inhibited oxidative damage induced by cocaine as reflected by mitochondrial superoxide radical and peroxide enhancement. Finally, (4) Tempol restored the total scavenging capacity which was reduced by cocaine in PC12 cells. Cumulatively, these results suggest that nitroxides such as Tempol can attenuate oxidative damage and cell death induced by cocaine and that PC12 cells can be used as an in vitro model to further investigate the precise molecular mechanism of these compounds.

ESTABLISHMENT OF A LARGE-SCALE MICROPROPAGATION SYSTEM FOR ANOECTOCHILUS FORMOSANUS IN BIOREACTORS

An efficient protocol was developed to optimize culture conditions for large-scale micropropagation of Anoectochilus formosanus using bioreactor technology relation to the growth, pigments, metabolite content and antioxidant properties. The proliferation response was significantly influenced by aeration volume in bioreactor culture. The highest shoot multiplication and shoot length were observed at 0.06 volume of air per volume of medium per min (vvm) aeration volume. This condition also resulted in higher fresh and dry weights. Number of shoots and shoot length were reduced by increasing aeration volume (from 0.09 to 0.12 vvm). Comparative studies between solid and liquid (bioreactor) cultures revealed that shoot multiplication and growth were more efficient at 0.06 wm air volume and 90 explants as initial inoculum size. Chlorophyll and carotenoid contents were increased with increasing inoculum density from 30 to 90 explants/culture vessel. In contrast, the lowest value was observed at an inoculum density of 120 explants. The highest contents of total phenol, flavonoid and DPPH radical scavenging activity were also obtained at an inoculum density of 90 explants. These results suggest that bioreactor technology can be successfully applied for the large-scale micropropagation of A. formosanus in a biotechnological approach.

Increased Total Scavenger Capacity and Decreased Liver Fat Content in Rats Fed Dehydroepiandrosterone and Its Sulphate on a High-Fat Diet

Background: Weak androgens have an antioxidant effect in vitro which is represented as a beneficial change in the antioxidant status. Objective: Our aim was to clarify whether dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulphate (DHEAS) oral administration results in beneficial antioxidant changes in Sprague-Dawley adult male rats in vivo. Methods: Groups of experimental animals were fed a high-fat or a normal-fat diet and treated with DHEA or DHEAS in the drinking fluid. The control group was fed a high-fat diet together with untreated drinking fluid. Total scavenger capacity (TSC) was measured before and after 4 weeks of treatment in blood samples using a chemiluminometric assay. Fat content, superoxide dismutase (SOD), catalase and glutathione S-transferase (GST) activity in the liver were determined by Sudan staining and spectrophotometric assessments, respectively, from the fresh frozen tissue. Results: DHEA and the DHEAS treatment showed significantly increased TSC in the groups fed a high-fat diet. The control group and the DHEA- or DHEAS-treated groups on normal diets showed no significant changes in TSC. The total score of liver fat content in the high-fat diet groups showed a marked positivity with Sudan staining, and the groups treated with DHEA or DHEAS had a markedly decreased amount of fat in the liver slides compared to the untreated group on the high-fat diet. Liver SOD activity was decreased in all high-fat diet groups and elevated only in the groups on a normal diet with DHEA or DHEAS treatment. Liver catalase and GST activities were decreased in the groups where TSC was significantly increased. Conclusion: Our results support the hypothesis that DHEA and DHEAS supplementation can improve the antioxidant status in lipid-rich dietary habits.

Studies on the phenolic profiling, anti-oxidant and cytotoxic activity of Indian honey: in vitro evaluation

Commercial honey types were screened for phenolic profile and anti-oxidant capacity. Phenolic profiling was done using high performance liquid chromatography, which was further corroborated with electro spray ionisation-mass spectroscopy. Dihydroxy benzoic acid, caffeic acid, ferulic acid and cinnamic acid were the major phenolic constituents found in the honey samples. The anti-oxidant content and free-radical scavenging effect of honey were established using various assays. Total anti-oxidant potential and free-radical scavenging ability varied among the honey varieties and exhibited significant correlation with their phenolic content. Further, honey samples with richly abundant phenolic content were found to limit oxidant-induced cell death more effectively. Cytotoxic studies of a selected sample on a breast cancer cell displayed growth inhibition, depending on the concentration used. Cell cycle analysis indicated increasing accumulation of cells at the sub-G1 phase. These results summarise the phenolic profile and anti-oxidant and cytotoxic potential of Indian honey samples for the first time.