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1.
Dioscorea batatas Decne (DBD) has been traditionally used as folk medicine and health food in Korea. One glycoprotein was isolated from DBD and confirmed to have 30 kDa molecular weight. The DBD glycoprotein was tested its antioxidative activity and characterized in various chemical conditions. The DBD glycoprotein has the optimal free radical scavenging activities in acidic and neutral pH and up to 85 °C. In the M2+ ions (Ca2+, Mn2+, and Mg2+) in the presence of EDTA, the activities of DBD glycoprotein reduced, compared to DBD glycoprotein alone without metal ion. Interestingly, the results in this study indicated that the activities of DBD glycoprotein do not depend on the presence of EDTA. Interestingly, when DBD glycoprotein was treated with deactivation agents (pronase E or NaIO4), scavenging activity of DBD glycoprotein was decreased. The anti-oxidative effects of DBD glycoprotein on hydroxyl radicals in cell-free system revealed, and the DBD glycoprotein has remarkable scavenging effects on hydroxyl radicals generated by G/GO. Furthermore, the results in this study showed that the DBD glycoprotein (200 μg/ml) significantly inhibits intracellular ROS amounts and protects from cytotoxicity in primary mouse splenocyte culture treated with GO (30 mU/ml). Therefore, we speculate that DBD glycoprotein has an antioxidative potential as one of natural antioxidants.  相似文献   

2.
BACKGROUND: Jellyfish collagen was hydrolysed with trypsin and properase E, and jellyfish collagen peptide (JCP) was purified from the enzymatic hydrolysate using ion exchange chromatography and gel filtration. The antioxidant activity of JCP in a linoleic acid emulsion system, its superoxide anion‐ and hydroxyl radical‐scavenging activities and its copper‐chelating ability were evaluated in vitro. Initial investigations of JCP's ability to inhibit melanogenesis were carried out using cultured B16 melanoma cells. RESULTS: The molecular weight distribution of JCP was from 400 to 1200 Da. Amino acid analysis showed that JCP was rich in Gly, Pro, Ser, Ala, Glu and Asp and had a total hydrophobic amino acid content of 384.2 g kg?1. JCP showed high antioxidant activity (IC50147.8 µg mL?1), superoxide anion‐scavenging activity (IC5021.9 µg mL?1), hydroxyl radical‐scavenging activity (IC5016.7 µg mL?1) and copper‐chelating ability (IC5088.7 µg mL?1) in vitro. It also significantly inhibited intracellular tyrosinase activity, decreased melanin content and enhanced glutathione synthesis (P < 0.05). Furthermore, JCP decreased intracellular cAMP levels and suppressed tyrosinase mRNA expression. CONCLUSION: Based on the results of this study, JCP exerts anti‐melanogenic actions via its antioxidant properties and copper‐chelating ability. JCP could be used as a natural skin‐lightening agent in the medicine and food industries. Copyright © 2009 Society of Chemical Industry  相似文献   

3.
The water‐soluble exo‐polysaccharides (WSEPS) and intrapolysaccharides (WSIPS) were prepared from the fermentation broth and mycelia of Isaria farinosa B05, respectively, and their antioxidant activities in vitro were studied by various antioxidant assays, including hydroxyl radical scavenging, superoxide radical scavenging, hydrogen peroxide (H2O2) scavenging, metal chelating activities, reducing power and antilipid peroxidation. The results show that the water‐soluble polysaccharides extracted from I. farinosa B05 had a high antioxidant activity in a concentration‐dependent manner (except the activity of antilipid peroxidation). WSIPS quenched hydroxyl radicals at high amounts but not at low amounts; WSEPS did not scavenge hydroxyl radicals. WSEPS and WSIPS had a similar activity in scavenging superoxide radicals. WSIPS had a slightly higher H2O2‐scavenging activity than WSEPS before the activity reached 100% at the amount of 10.24 mg. Similar to the result of hydroxyl radical scavenging, WSIPS, but not WSEPS, chelated Fe2+. The reductive ability of WSEPS and WSIPS was similar and significant compared with the control at the range of 0.8–6.4 mg. Both WSEPS and WSIPS showed higher antilipid peroxidation activities at low amounts (≤ 0.64 mg) than at high amounts. These results indicate that WSEPS and WSIPS had strong antioxidant activities and can be explored as novel potential antioxidants.  相似文献   

4.
Wheat gluten was hydrolysed by Alcalase 2.4L under ultrasound. Different antioxidant assays in vitro, such as ferrous ion‐chelating activity, reducing power, inhibition of linoleic acid emulsion peroxidation and 2,2′‐azinobis (3‐ethylbenzothiazoline‐6‐sulphonic acid) diammonium salt (ABTS) radical scavenging activity, were employed to evaluate the antioxidant activities of the wheat gluten hydrolysate (WGH) obtained. It was found that WGHL (WGH which was obtained by low frequency (LF) ultrasound) exhibited the strongest antioxidant activities, with an EC50 value of 0.513 mg mL?1 for ferrous iron‐chelating activity, as well as a high and dose‐dependent reducing power. In the linoleic acid system, a longer induction time indicated a significant decrease of lipid peroxidation. In addition, WGH also exhibited notable ABTS radical scavenging activity. A good correlation was observed between antioxidant activities and the amount of WGH, but a poor correlation was observed between antioxidant activities and degree of hydrolysis. The molecular weight distribution of WGH was affected by ultrasonic frequency and WGHL had the highest proportion of peptide fractions of molecular weight 3000–500 Da. All the results showed that the WGH treated by ultrasound had strong antioxidant activities and low molecular weight.  相似文献   

5.
Brown algae, Ecklonia cava has been regarded as a useful material in the prevention or treatment of several human diseases in Jeju Island, Korea. In this study, we investigated its antioxidant activity, and isolated a new antioxidative compound, which was identified as 2,7″-phloroglucinol-6,6′-bieckol (PHB) on the basis of LC/MS, as well as 1H and 13C NMR spectroscopy results. The antioxidant activity of PHB was evaluated via several in vitro assays, such as radical scavenging activities using electron spin resonance spectrometry, intracellular reactive oxygen species scavenging activity, and DNA damage assays. PHB evidenced profound scavenging activities on DPPH, alkyl, hydroxyl, and superoxide radicals (IC50: 0.51, 2.07, 75.64 and 57.19 μM for DPPH, alkyl, hydroxyl and superoxide radicals, respectively). The antioxidant activity of PHB was higher than that of ascorbic acid. Furthermore, PHB effectively inhibited H2O2-induced DNA damage. The results of this study indicate that PHB may prove useful as a novel natural marine antioxidant.  相似文献   

6.
Barks of various plants have been reported to possess both in vitro and in vivo antioxidant activity. In this study, antioxidant activity of the extract from the barks of Dillenia indica was evaluated by various in vitro methods. The bark of D. indica was extracted with 70% aqueous acetone. The total phenolic content was determined by Folin-Ciocalteu method and the antioxidant activity was assayed through various in vitro methods such as antioxidant capacity by phosphomolybdenum method, radical scavenging activity using α, α-diphenyl-β-picrylhydrazyl method, hydroxyl radical (?OH) scavenging activity by deoxyribose method, and superoxide anion (O2 ??) scavenging activity by phenazine methosulphate/NADH-nitroblue tetrazolium system. The total phenolic content of the extract as tannic acid equivalents was 54%. The total antioxidant capacity of the extract was found to be 3.12 mmoles/g as equivalent to ascorbic acid at 50 ppm concentration. At 25 ppm concentration, the radical scavenging activity of butylated hydroxyanisole and extract showed 90.9% and 91.0%, respectively. The ?OH scavenging activity of the extract was shown to be 53.9% at 100 ppm concentration. At a concentration of 50 μg, the O2 ?? scavenging activity of the extract was 31.7% as compared to 47.7% by gallic acid. These results indicated that Dillenia indica barks contained large amount of phenolics and possessed potent antioxidant property.  相似文献   

7.
Dill (Anethum graveolens L.) have been extensively used in salads, soups, and pickles for its aromatic odor and flavor. Recently, interest in plant-derived food additives has grown. In this study, the possible antioxidant properties of water, ethanol, and acetone extracts of dill leaves were investigated. In order to evaluate antioxidant activities of all extracts, different antioxidant tests were used, such as total antioxidant activity by ferric thiocyanate method, reducing power, DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical scavenging, hydrogen peroxide scavenging, and ferrous ions chelating activities. The content of phenolic compounds was also determined to be the gallic acid equivalent. Among the three extracts, the water extract of dill leaf showed the most potent antioxidative capacity in each assay, showing 79.66% (at 1 mg/mL) in the DPPH? radical scavenging activity, 63% (at 800 μg/mL) in the metal chelating effect, 60% (at 400 μg/mL) in the H2O2 scavenging activity, and 0.61 absorbance (at 1 mg/mL) in the reducing power.  相似文献   

8.
Three different biochemical test systems were chosen based on their solubility to study the antioxidant activity of ginger extracts. Reducing power and DPPH. scavenging activity tests were considered to produce hydrophilic environments and the H2O2 test was considered as creating a lipophilic environment. The average yields were 10.23 ± 1.02% and 0.48 ± 0.19% for oleoresin and essential oil, respectively. The content of total phenols was 67.6 ± 1.08 mg GAE/g of dry extract. In terms of EC50, in hydrophilic environment standards, it showed the highest effects compared to ginger extracts, with oleoresin presenting more activity than essential oil. In contrast, except for quercetin, essential oil showed the best scavenging activity in inhibiting H2O2 compared to all other antioxidants. The present work demonstrated that, when using reducing power, DPPH· free radical scavenging and H2O2 scavenging assays, the same ginger extracts exhibit different antioxidant activities, which were affected not only by the extract itself but also by the chemical environment (hydrophilic/lipophilic).  相似文献   

9.
BACKGROUND: To investigate the volatile compounds and the antibacterial and antioxidant effects of the essential oils of Pinus densiflora needles (EPDN) and Pinus thunbergii needles (EPTN), the volatile compounds of steam‐distilled essential oils were analysed by gas chromatography–mass spectrometry. Antibacterial activities were analysed by performing disc‐agar diffusion assay and determining the minimum inhibitory concentrations (MICs) of the essential oils. Antioxidant activities were analysed via radical‐ and nitrite‐scavenging activity assays. RESULTS: The yields of EPDN and EPTN were 0.304% (v/w) and 0.296% (v/w), respectively. In the antibacterial activity assay, the MICs of EPDN and EPTN for Klebsiella pneumoniae, Shigella flexneri and Proteus vulgaris were < 0.4 mg mL?1. In the antioxidant activity assay, the 50% inhibitory concentrations (IC50) of EPDN and EPTN were 120 and 30 µg mL?1, respectively. At 1680 µg mL?1, both EPDN and EPTN exhibited > 50% nitrite‐scavenging activity. CONCLUSION: EPDN can be used as a natural antimicrobial substance. Copyright © 2011 Society of Chemical Industry  相似文献   

10.
Fringe tree (Chionanthus virginicus L.), a shrub of the eastern part of America, used as a raw material by pharmaceutical industries for cholagoque, diuretic, tonic and the preparation of homeopathic tinctures. The identification of lignans as major antioxidant components and determination of their antioxidant activities are of considerable interest, because of the role they play in pharmacological actions. The potential antioxidant activity of the lignans such as phillyrin, pinoresinol-β-d-glucoside (PDG) and pinoresinol di-β-d-glucoside (PDDG) from root bark of fringe tree (C. virginicus L.) were examined by different antioxidant tests including; 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, superoxide anion radical (O2 •-) scavenging, total antioxidant activity by ferric thiocyanate method, reducing activity by Fe3+–Fe2+ transformation, hydrogen peroxide (H2O2) scavenging and ferrous metal (Fe+2) chelating activities. Phillyrin, PDG and PDDG, as antioxidants, neutralized the activities of radicals and inhibited the peroxidation reactions of linoleic acid emulsion. The total antioxidant activity was determined according to the ferric thiocyanate method. Butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox, which is a water-soluble analogue of tocopherol, were used as the reference antioxidant compounds. Phillyrin, PDG and PDDG showed 67.6, 77.3 and 64.2% inhibition on lipid peroxidation of linoleic acid emulsion, respectively, at the concentration of 20 μg/mL. On the other hand, BHA, BHT, α-tocopherol and trolox exhibited 74.4, 71.2, 54.7 and 20.6% inhibition on peroxidation of linoleic acid emulsion, respectively, at the above mentioned concentration. In addition, phillyrin, PDG and PDDG were effective on DPPH, ABTS•+ and O2 •- scavenging, H2O2 scavenging, total reducing power and metal chelating effect on ferrous ions activities. Also, BHA, BHT, α-tocopherol and trolox were used as references antioxidants for these various antioxidant activities.  相似文献   

11.
In the present study, in vitro antioxidant and free radical scavenging capacity of methanol extracts from 10 underutilized fruits viz., Syzygium cumini, Murraya koenigii, Coccinia grandis, Opuntia dillenii, Carissa carandus, Kirganalia reticulata, Canthium parviflorum, Lantana camara, Alangium lamarckii, and Morus alba were evaluated using established in vitro models such as ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picryl-hydrazyl (DPPH), 2,2′azinobis(3-ethylbenzothiozoline-6-sulfonic acid) diammonium salt (ABTS), hydroxyl radical (OH), nitric oxide radical (NO), super oxide radical (O2• −) scavenging, and metal chelating activities. All the fruit extracts contained substantial concentration of total phenolics, tannins, and flavonoids. The extracts of O. dillenii, M. koenigii, K. reticulata, L. camara, and M. alba registered higher activity in DPPH, ABTS• +, and FRAP assays. Phenolic content of these fruits is significantly correlated with antioxidant capacity. Interestingly, all the extracts showed considerable nitric oxide, super oxide, and hydroxyl radical scavenging activities in a dose dependant manner when compared with the standard butylatedhydroxyl anisole (BHA). Our findings revealed that these underutilized fruits have potential as good sources of natural antioxidant/nutraceutical compounds.  相似文献   

12.
Fermented soybean protein meal hydrolysate (FSPMH) was fractionated by gel filtration on Sephadex G-15. The fractions obtained were subjected to various antioxidant assays, amino acid and molecular weight determinations. Among the seven fractions, the highest antioxidant activity was found in fraction F2, with significant differences (P < 0.01) 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, hydroxyl radicals (.OH) scavenging and Cu2+ chelating activity. Fraction F2 exhibited scavenging of DPPH (59.43%), .OH (72.80%) and 44.47% Cu2+ chelating activity. All other fractions showed variable activities in different assays. Amino acid analyses of F2 fraction with the strongest antioxidant activity also had the highest percentage of related antioxidative amino acids content (Histidine 3.46, Serine 5.78, Valine 4.08 and Lysine 11.49 g/100 g protein) compared with other six fractions. The molecular weight distribution of F2 was found to vary from 170 to 1500 Da.  相似文献   

13.
In the present study, the alcalase-generated proteolysates obtained after 8 h of proteolysis of stone fish flesh showed the most potent antioxidant activity in terms of DPPH? radical scavenging activity (77.43%, IC50 of 0.5 mg/mL), ABTS? radical scavenging activity (92.73%, IC50 of 0.33 mg/mL) and FRAP value (39.2 mmol/100 mL FeSO4). These proteolysates profiled and characterized as antioxidative peptides. The proteolysates were initially subjected to ultrafiltration using MWCO Spin-X UF. Potent fractions were further characterized based on hydrophobicity using reversed-phase high-performance liquid chromatography (RP-HPLC) and isoelectric point using an OFFGEL isoelectric focusing fractionator. Results indicated that most of the antioxidative peptides found in fractions with a molecular weight (MW) of less than 2 kDa, hydrophilic (hydrophilicity >80%) and basic (pI = 9.7). The final purified fraction with the highest antioxidant activity was selected for peptide identification and sequencing using Q-TOF mass spectrometry. A total of four peptides were identified, from which Peptide 1 (GVSGLHID) showed the highest antioxidant activity and this has potential as a novel bioingredient of nutraceuticals and functional foods to promote human health.  相似文献   

14.
The abilities of broccoli seed extracts and purified sulforaphane (SF) to scavenge 2,2′‐azinobis [3‐ethylbenzothiazoline‐6‐sulphonate] (ABTS?+), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH?) and superoxide anions were studied. The free radical scavenging activities of broccoli seed extracts had no exact correlation with SF content, indicating that SF was not the main antioxidant component. The broccoli seed extracts were separated by high‐speed countercurrent chromatography to obtain purified SF, which showed dose‐dependent free radical scavenging activities in the DPPH? and ABTS?+ assays, but its activities were weaker to those of ascorbic acid. The same trend was observed in the chemiluminescence assay. The results showed that broccoli seed extracts had strong free radical scavenging activities that were not attributable to SF.  相似文献   

15.
Bioactive compounds in the edible parts of fresh and dried Jaffa® sweeties, a new kind of citrus fruit, were analysed and their antioxidant capacities were assessed. Antioxidant‐rich fractions were extracted from fresh and dried sweeties with 1.2 M HCl in methanol/water (1:1 v/v), and the antioxidant activities of these extracts were evaluated. Using the β‐carotene/linoleate model system, the extracts from equivalent quantities of fresh and dried sweeties showed 89 and 87% antioxidant activity respectively. Similarly, using the DPPH radical‐scavenging method, the extracts showed 87 and 85% antioxidant activity respectively. The best correlations were between caffeic acid content and β‐carotene and DPPH antioxidant activity values (r = 0.9849 and 0.9798 respectively, p = 0.005). Both fresh and dried sweeties are bioactive natural products; when fresh fruits are not available, properly dried sweeties could be used as a substitute. Copyright © 2004 Society of Chemical Industry  相似文献   

16.
Antioxidant potential and total phenolics content of 70% acetone extracts of the raw and processed seeds of Bauhinia vahlii were evaluated. The extract of raw seeds contained higher levels of total phenolics (30.8 g/100 g) and tannins (19.6 g/100 g) compared to dry heated and soaking followed by autoclaving seed extracts. Extracts were screened for antioxidant and free radical scavenging activities using various chemical and in vitro model systems. In all the models, except DPPH radical scavenging activity, the extract from raw seeds manifested the strongest antioxidant activity than that from processed seeds. In β-carotene/linoleic acid emulsion system and superoxide scavenging activity, the raw seed extract registered more activity when compared to the standards (butylated hydroxyanisole and α-tocopherol). Whereas, the extract from dry heated seed exhibited higher DPPH· scavenging activity (IC50 70.77 μg/mL) than the raw seeds (IC50 74.4 μg/mL). This study has to some extent validated the antioxidant potential of the seeds of B. vahlii.  相似文献   

17.
The effective utilisation of Moringa oleiferia mature leaves (MOL) extract as an antioxidant in cooked goat meat patties during refrigerated storage was investigated, and its efficiency was evaluated against butylated hydroxytoluene (BHT). The extract exhibited high phenolic content (48.36 mg of gallic acid equivalent per g), flavonoid (31.42 mg g?1 of sample) being the major component. Moringa oleiferia mature leaves extract showed excellent antioxidant activity as determined by radical‐scavenging activity of 1, 1‐diphenyl 2 picrylhydrazyl (DPPH). The IC50 value of MOL extract for 2, 2‐diphenyl‐1‐picrylhydrazyl radical scavenging was 18.54 μg mL?1. Total phenolic content (as gallic acid equivalent) significantly (P < 0.05) increased from 285.56 in control to 379.45 in patties with MOL extract. MOL extract (0.1%) when added to meat was found to retard lipid peroxidation of cooked goat meat patties as measured by TBARS number during refrigerated storage. The increase in TBARS number in MOL extract–treated samples was very slow and remained lowest (0.53 mg malonaldehyde per kg sample) up to 15 days. The antioxidant activity of MOL extract was found to be comparable to BHT. Addition of MOL extract did not affect any of the sensory attributes of patties. The MOL extract at a level of 100 mg/100 g meat was sufficient to protect goat meat patties against oxidative rancidity for periods longer than the most commonly used synthetic antioxidant like BHT.  相似文献   

18.
The present study was carried out to determine the antioxidant and different free radical scavenging activities of 70% methanolic extract of Diplazium esculentum. Total antioxidant activity of the extract was evaluated as trolox equivalent antioxidant capacity value. The IC50 values for scavenging of different free radicals indicated its efficient free radical scavenging properties. The extract acted as an iron chelator and also possessed reducing power. It also inhibited lipid peroxidation. Moreover, the extract yielded high phenolic and flavonoid content. Therefore, the results indicated that 70% methanolic extract of D. esculentum acted as a potential antioxidant and free radical scavenger.  相似文献   

19.
The hard shell of a hazelnut is a major waste of the hazelnut industry. The chemical composition, phenolic compounds (total phenolics, tannins and condensed tannins), antioxidant activity (DPPH and ABTS free‐radical scavenging assays), and the relationships between phenolic compounds and antioxidant activities of the hazelnut shells from twelve US grown cultivars were investigated to for potential commercial development. Crude fibre accounted for over 85% of total carbohydrate. The shells contained high concentrations of phenolic compounds. Concentrations of phenolic constituents and ABTS?+ ‐scavenging capacities were significantly higher (P > 0.05) in the Oregon cultivars than their Nebraska counterparts. There were significant positive correlations between ABTS?+ scavenging capacities and the phenolic compounds, whereas DPPH? ‐scavenging capacity demonstrated a weak negative correlation with ABTS?+ scavenging capacity and the phenolics. The results suggest that hazelnut hard shell may serve as a potential source of natural antioxidants for food applications.  相似文献   

20.
Antioxidant Effect of Korean Traditional Lotus Liquor (Yunyupju)   总被引:1,自引:0,他引:1  
This study presented the antioxidant activities of the Korean traditional lotus liquor (Yunyupju) made from lotus blossom and leaves. The antioxidant activities are dose‐dependent and reached a plateau (about 80% inhibition) when the concentration of lotus liquor exceeded 25 μg in a modified linoleic acid peroxidation induced by haemoglobin. The concentrations to attain one absorbance unit at 700 nm were 23.6 ± 1.2 μg for Butylated hydroxytolene (BHT), and 45.7 ± 5.4 μg for lotus liquor. The scavenging activities of DPPH exerted by lotus liquor as well as α‐tocopherol were tested. Linear response curves were also obtained and the IC50 were estimated as 5.6 μg for α‐tocopherol, 17.9 μg for lotus liquor. The maximum scavenging activity on hydroxyl radicals (40%) could be achieved when lotus liquor was more than 500 μg. Lotus liquor also has a potent superoxide radical scavenging activity, with value of 0.93 unit mg?1 as superoxide dismutase equivalents. The IC50 was estimated as 1.07 ± 0.04 mg for lotus liquor. The high performance liquid chromatography analysis of polyphenols was successfully achieved as these compounds appeared at 16.30 (catechin), 21.87 (rutin), 25.88 (unidentified peak), 31.51 (quercitrin), 35.19 (myricetin), and 36.72 (quercetin) min after injection of the sample, respectively.  相似文献   

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