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1.
Several studies indicated that bifidobacteria possessed strong antioxidant activity. In present study, the antioxidant activities of Bifidobacterium animalis 01 proteins were evaluated using six assays, namely, linoleic acid preoxidation assay, erythrocyte hemolysis assay, 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, reducing power assay, hydroxyl (OH) and superoxide radicals (O2?) assays, in which the last two assays were measured by electron spin resonance (ESR). There were two kinds of B. animalis 01 proteins in this study, the regular B. animalis 01 protein (Pro-CK) and the B. animalis 01 selenium-contained protein (Pro-Se). Both Pro-CK and Pro-Se showed concentration dependent antioxidant activity in DPPH assay, reducing power assay and erythrocyte hemolysis assay. All results of six assays indicated that the antioxidant activity of the B. animalis 01 protein was improved remarkably after selenium was incorporated. The antioxidant activity of Pro-Se increased with the increase of selenium content in Pro-Se suggesting selenium played a positive role in enhancing the antioxidant activity of B. animalis 01 protein. Moreover, organic selenium was more effective than inorganic selenium on enhancing the hydroxyl radical scavenging ability of B. animalis 01 protein.  相似文献   

2.
In order to investigate polymeric flavonoids, the polycondensate of catechin with glyoxylic acid (PCG) was prepared and its chemically antioxidant, cellular antioxidant (CAA) and α-glucosidase inhibitory activities were evaluated. The DPPH and ABTS radical scavenging activities and antiproliferative effect of PCG were lower than those of catechin, while PCG had higher CAA activity than catechin. In addition, PCG had very high α-glucosidase inhibitory activities (IC50 value, 2.59 μg/mL) in comparison to catechin (IC50 value, 239.27 μg/mL). Inhibition kinetics suggested that both PCG and catechin demonstrated a mixture of noncompetitive and anticompetitive inhibition. The enhanced CAA and α-glucosidase inhibitor activities of PCG could be due to catechin polymerization enhancing the binding capacity to the cellular membrane and enzymes.  相似文献   

3.
Date palm (P. dactylifera) plays a vital role in ethnomedicinal practices in several parts of the world. There are over 2000 cultivars of date palm that differ in chemical composition and extent of bioactivity. The present study was undertaken to comparatively evaluate the antioxidant potential of three cultivars of date palm (Ajwah, Safawy and Sukkari) from Saudi Arabia and analyze their phenolic constituents in order to draw a rationale for their activity. Antioxidant activities of the date cultivars were evaluated by different quantitative methods including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical scavenging assay, total antioxidant capacity, reducing power, total phenolic (TPC), flavonoid (TFC) and tannin content (TTC), while qualitative phenolic composition was determined using ultra performance liquid chromatography coupled to quadropole time of flight mass spectrometry (UPLC-QTOF-MS). All the three date extracts showed good DPPH radical scavenging (IC50 103–177 μg/mL) and hydroxyl radical scavenging (IC50 1.1–1.55 mg/mL) activity and total antioxidant capacity (IC50 87–192 μg/mL). The reducing power was also comparable to that of ascorbic acid, used as standard in above experiments. All the three samples contain significant amount of major antioxidant components (phenolic, flavonoid and tannin) that successfully correlates with the results of radical scavenging assays. UPLC-QTOF-MS revealed a total of 22 compounds in these date cultivars classified into common phenolics, flavonoids, sterols and phytoestrogens. Significant variation in the degree of antioxidant activity of these three date cultivars can be attributed to the difference in the content and composition of phenolic compounds.  相似文献   

4.
蓝莓果渣提取物总酚含量及抗氧化活性研究   总被引:6,自引:0,他引:6  
高畅  程大海  高欣  赵尔丰 《植物研究》2010,30(2):253-256
研究了蓝莓果渣提取物总酚含量及其抗氧化活性。分别采用水、40%乙醇及纤维素酶辅助乙醇超声提取蓝莓果渣,并用Folin-Ciocalteu试剂对3种提取物的总酚含量进行评估;并采用DPPH清除实验及O2—.清除实验对3种提取物的抗氧化活性进行研究。实验结果表明,纤维素酶辅助超声提取蓝莓果渣的总酚含量最高,可达425.36±15.21 mg GAE.100 g-1DW,远远高于水提物(169.46±9.75 mg GAE.100 g-1DW)及醇提物(218.39±12.54mg GAE.100 g-1DW)中的总酚含量。且纤维素酶辅助乙醇超声提取物对DPPH的清除能力为2.67±0.13 gVc.100 g-1DW,对O—.2的清除能力2.48±0.14 g Vc.100 g-1DW,明显好于醇提物及水提物抗氧化活性。  相似文献   

5.
The present study was designated to evaluate the antioxidant, antibacterial and antischistosomal activities of Grateloupia livida (GL) extracts in vitro. A GL Ethanol extract (EE) was separated into petroleum ether (PE), ethyl acetate (EA), n-butyl alcohol (BuOH) and aqueous (AQ) fractions to fractionate the polar and non-polar compounds in the EE. Extracts antioxidant activities were evaluated in vitro by DPPH radical-scavenging, deoxyribose radical scavenging, and β-carotene bleaching assays, all using butylated hydroxytoluene (BHT) as the reference antioxidant compound. The most effective antioxidant properties were observed in the PE fraction in all three assays. Antimicrobial testing showed that the PE fraction exhibited broad-spectrum antimicrobial activity, with the PE fraction also exhibiting strong activity against the human pathogenic trematode S. japonicum adult worm. In order to investigate the relationships between bioactivity and chemical composition, the chemical composition of the PE fraction was analyzed by gas chromatography-mass spectrometry (GC-MS). In total, 25 components were identified in the PE fraction, most of which have known antioxidant and antimicrobial activities. However, none of the compounds have reported activity against Schistosoma, suggesting that the schistosomicidal activity of the PE fraction may be related to minor constituents present in the extract, or governed by more intricate synergistic or additive relationships. Finally, fractions with the greatest biological activity displayed neither cellular cytotoxicity, at concentrations up to 100 ug/ml, or acute oral toxicity in mice, at doses up to 2000 mg/kg. Based on antioxidant, antimicrobial, antischistosomal activities, and low toxicity, the PE fraction possesses properties useful for food preservation and overall improvement of human health.  相似文献   

6.
香桃木叶片粗多酚抗氧化活性的研究   总被引:2,自引:1,他引:2  
以香桃木叶片为材料,60%乙醇提取获得粗多酚样品,并对样品的油脂抗氧化性和自由基清除能力进行研究。结果表明,未经纯化的香桃木粗多酚对油脂抗氧化效果优于BHT和VC等人工合成抗氧化剂;在清除自由基的实验中,相同浓度的香桃木粗多酚对DPPH自由基的清除率为VE的5倍,对羟自由基的清除效果也略优于VC。由此可以预见香桃木粗多酚在精细加工、经纯化后抗氧化效果会更加显著。  相似文献   

7.
The study explored on the commonly available weed plant Commelina nudiflora which has potential in-vitro antioxidant and antimicrobial activity. The different polar solvents such as ethanol, chloroform, dichloromethane, hexane and aqueous were used for the soxhlet extraction. The extracts were identified pharmacologically as important bioactive compounds and their potential free radical scavenging activities, and antimicrobial properties were studied. C. nudiflora extracts were monitored on their in-vitro antioxidant ability by DPPH and ABTS radical scavenging assay. Aqueous extract shows significant free radical scavenging activity of 63.4 mg/GAE and 49.10 mg/g in DPPH and ABTS respectively. Furthermore, the aqueous crude extract was used in antibacterial studies, which shows the highest inhibitory activity against Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi. Among all the extracts, aqueous extract of C. nudiflora has significant control over free radical scavenging activity and inhibition of the growth of food pathogenic bacteria. Also, the aqueous extract contains abundance of phenolics and flavonoids higher than other extracts. This study explored weed plant C. nudiflora as a potential source of antioxidant and antibacterial efficacy and identified various therapeutic value bioactive compounds from GC–MS analysis.Abbreviations: ABTS, 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid), DPPH, 2,2-diphenyl-1-picrylhydrazyl, GAE, gallic acid equivalent, GC–MS, gas chromatography and mass spectrometry  相似文献   

8.
Content of total proanthocyanidins as well as total phenolics, flavonoids, antioxidant activities were evaluated for litchi (Litchi chinensis Sonn.) pulp of 32 cultivars. One cultivar, Hemaoli, showed the highest total proanthocyanidins and total phenolics, and DPPH or ABTS radical scavenging activities. ESI-MS and NMR analysis of the Hemaoli pulp crude extracts (HPCE) showed that procyandins composed of (epi)catechin unites with degree of polymerization (DP) of 2–6 were dominant proanthocyanidins in HPCE. After the HPCE was fractionated by a Sephadex LH-20 column, 32 procyanidins were identified by LC-ESI-Q-TOF-MS in litchi pulp for the first time. Quantification of individual procyanidin in HPCE indicated that epicatechin, procyanidin B2, procyanidin C1 and A-type procyanidin trimer were the main procyanidins. The radical scavenging activities of different fractions of HPCE as well as six procyanidins standards were evaluated by both DPPH and ABTS assays. HPCE fractions showed similar antioxidant activities with those of Vc and six individual procyanidins, the IC50 of which ranged from 1.88 ± 0.01 to 2.82 ± 0.10 μg/ml for DPPH assay, and from 1.52 ± 0.17 to 2.71 ± 0.15 μg/ml for ABTS assay. Such results indicate that litchi cultivars rich in proanthocyanidins are good resources of dietary antioxidants and have the potential to contribute to human health.  相似文献   

9.
A widely used herbal medicine, Ixeris sonchifolia (Bge.) Hance Injectable (ISHI) was investigated for quality consistency. Characteristic fingerprints of 23 batches of the ISHI samples were generated at five wavelengths and evaluated by the systematic quantitative fingerprint method (SQFM) as well as simultaneous analysis of the content of seven marker compounds. Chemometric methods, i.e., support vector machine (SVM) and principal component analysis (PCA) were performed to assist in fingerprint evaluation of the ISHI samples. Qualitative classification of the ISHI samples by SVM was consistent with PCA, and in agreement with the quantitative evaluation by SQFM. In addition, the antioxidant activities of the ISHI samples were determined by both the off-line and on-line DPPH (2, 2-diphenyl-1-picryldrazyl) radical scavenging assays. A fingerprint–efficacy relationship linking the chemical components and in vitro antioxidant activity was established and validated using the partial least squares (PLS) and orthogonal projection to latent structures (OPLS) models; and the online DPPH assay further revealed those components that had position contribution to the total antioxidant activity. Therefore, the combined use of the chemometric methods, quantitative fingerprint evaluation by SQFM, and multiple marker compound analysis in conjunction with the assay of antioxidant activity provides a powerful and holistic approach to evaluate quality consistency of herbal medicines and their preparations.  相似文献   

10.
The present study aims to investigate the levels of polyphenols and antioxidant activity in one of the most important commercial species of seaweeds in Kamchatka, an edible brown seaweed Saccharina bongardiana. Six extracts of S. bongardiana, acetone, methanol, ethanol, and the respective 70 % aqueous solutions, were assessed for total phenol content in order to determine the most efficient extracting solvent. The total phenol content was measured by the Folin–Ciocalteu method and expressed as phloroglucinol equivalents (PGE). The antioxidant tests used were 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, linoleic acid-β carotene oxidation inhibiting assay, and Fe2+ ion chelating method. Higher phenolic contents were obtained using aqueous organic solvents, as compared to the respective absolute solvents; 70 % acetone was found to be the most efficient solvent (1.039 mg PGE 100 mg?1 dry algal powder). High significant correlations were noted between total phenol content and the tested antioxidant activities; so the aqueous organic extracts exhibited the highest antioxidant activities versus DPPH radicals (EC50 values of 0.6–1.1 mg dry weight (DW) mL?1), linoleic acid-β carotene oxidation (74–78 % at 0.8 mg DW mL?1), as well as ferrous ions (EC50 values of 5.0–7.9 mg DW mL?1). Some methodological recommendations regarding the assays used and the expression of results are proposed.  相似文献   

11.
In the present study, we determined the antioxidant activity of cepharanthine and fangchinoline from Stephania rotunda by performing different in vitro antioxidant assays, including 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, N,N- dimethyl-p-phenylenediamine dihydrochloride (DMPD) radical scavenging, superoxide anion (O2?–) radical scavenging, hydrogen peroxide scavenging, total antioxidant activity, reducing power, and ferrous ion (Fe2+) chelating activities. Cepharanthine and fangchinoline showed 94.6 and 93.3% inhibition on lipid peroxidation of linoleic acid emulsion at 30 μg/mL concentration, respectively. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol, and trolox indicated inhibitions of 83.3, 92.2, 72.4, and 81.3% on peroxidation of linoleic acid emulsion at the same concentration (30 μg/mL), respectively. According to the results, cepharanthine and fangchinoline have effective antioxidant and radical scavenging activity.  相似文献   

12.
Antioxidant and antiradical activities of L-carnitine   总被引:2,自引:0,他引:2  
Gülçin I 《Life sciences》2006,78(8):803-811
L-carnitine plays an important regulatory role in the mitochondrial transport of long-chain free fatty acids. In this study, the antioxidant activity of L-carnitine was investigated as in vitro. The antioxidant properties of the L-carnitine were evaluated by using different antioxidant assays such as 1, 1-diphenyl-2-picryl-hydrazyl free radical (DPPH.) scavenging, total antioxidant activity, reducing power, superoxide anion radical scavenging, hydrogen peroxide scavenging and metal chelating activities. Total antioxidant activity was measured according to ferric thiocyanate method. alpha-tocopherol and trolox, a water-soluble analogue of tocopherol, were used as the reference antioxidant compounds. At the concentrations of 15, 30 and 45 microg/mL, l-carnitine showed 94.6%, 95.4% and 97.1% inhibition on lipid peroxidation of linoleic acid emulsion, respectively. On the other hand, 45 microg/mL of standard antioxidant such as alpha-tocopherol and trolox indicated an inhibition of 88.8% and 86.2% on peroxidation of linoleic acid emulsion, respectively. In addition, L-carnitine had an effective DPPH. scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities. Also, those various antioxidant activities were compared to alpha-tocopherol and trolox as references antioxidants.  相似文献   

13.
In the present study antioxidant activities by (1,1-diphenyl-2-picrylhydrazyl radical (DPPH), hydrogen peroxide, hydroxyl radical inhibition, hemolysis by hydrogen peroxide assay, reducing power and total antioxidant activities of polyphenolic extract of Ichnocarpus frutescens leaves were investigated. The flavonoids and total polyphenolic contents of the extract were also determined using standard methods. Phytochemical analyses revealed the presence of flavonoids, polyphenols, anthocyanins and simple phenolic acids. The results of antioxidant activities of polyphenol extract obtained by different in vitro methods were varied depending on the method used. Nevertheless, polyphenol extract showed significant inhibitory activities in all in vitro reactive oxygen species scavenging, might be attributed due to the high level of polyphenolic compound. Also, these various antioxidant activities were compared to α-tocopherol and l-ascorbic acid as reference antioxidant compounds. These findings provide evidence that the polyphenolic extract of I. frutescens is a natural source of antioxidant against oxidative damage.  相似文献   

14.
In current study, we report efficient and clean procedure for preparing mycosporine‐like amino acids (MMAs) analogs and evaluate their ultraviolet absorbance properties and antioxidant activities. The ultraviolet radiation absorbance patterns of the compounds were recorded and then used to define their molar absorptivities. The antioxidant activities were assessed using 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging and superoxide radical scavenging assays. Eight of nine compounds showed good activity against superoxide radicals, as only one of the analogs exhibited a measurable IC50 in the DPPH assay. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:305‐312, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21489  相似文献   

15.
Antioxidant and anti-inflammatory activities were found from Crocodylus siamensis (C. siamensis) blood. The 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, nitric oxide scavenging, hydroxyl radical scavenging and linoleic peroxidation assays were used to investigate the antioxidant activities of the crocodile blood. Results show that crocodile blood components had antioxidant activity, especially hemoglobin (40.58 % nitric oxide radical inhibition), crude leukocyte extract (78 % linoleic peroxidation inhibition) and plasma (57.27 % hydroxyl radical inhibition). Additionally, the anti-inflammatory activity of the crocodile blood was studied using murine macrophage (RAW 264.7) as a model. The results show that hemoglobin, crude leukocyte extract and plasma were not toxic to RAW 264.7 cells. Also they showed anti-inflammatory activity by reduced nitric oxide (NO) and interleukin 6 (IL-6) productions from lipopolysaccharide (LPS)-stimulated cells. The NO inhibition percentages of hemoglobin, crude leukocyte extract and plasma were 31.9, 48.24 and 44.27 %, respectively. However, only crude leukocyte extract could inhibit IL-6 production. So, the results of this research directly indicate that hemoglobin, crude leukocyte extract and plasma of C. siamensis blood provide both antioxidant and anti-inflammatory activities, which could be used as a supplementary agent in pharmaceutical products.  相似文献   

16.
通过DPPH自由基清除测定、还原能力、总抗氧化能力、羟自由基清除测定,评价有柄石韦Pyrrosia petiolosa醇提物的抗氧化活性。结果显示,有柄石韦醇提物清除DPPH·的IC50为75.82 μg·mL-1,清除·OH的IC50为46.30 μg·mL-1。有柄石韦醇提物清除DPPH· 的能力强于抗坏血酸,清除·OH的能力弱于抗坏血酸;同时,其还原能力和总抗氧化能力均强于抗坏血酸。该结果说明有柄石韦醇提物具有较强的抗氧化活性。  相似文献   

17.
印度块菌提取物抗氧化活性的研究   总被引:4,自引:0,他引:4  
郭坦  侯成林  魏磊  孙娟  范黎 《菌物学报》2010,29(4):569-575
对印度块菌Tuber indicum子实体的提取物,包括55%乙醇粗提物(ECE)、石油醚提取物(PEF)和乙酸乙酯提取物(EAF)的清除DPPH自由基和羟基自由基能力、铁离子鳌合能力以及各提取物的总酚含量等进行了研究和测定,结果显示,3种提取物的清除自由基能力和铁离子鳌合能力具有显著差异(P0.05);ECE对DPPH自由基的清除活性最高,其EC50值为1.61g/L;EAF对羟基自由基及铁离子表现出较强的清除或螯合的能力,其EC50值分别为3.31g/L和0.70g/L;EAF的总酚含量(2.964mg GAE/g提取物)最高,其次是ECE,总酚含量为(2.618mg GAE/g提取物);PEF的清除自由基和铁离子鳌合能力较差,其总酚含量也最低(1.124mg GAE/g提取物);总酚含量与印度块菌提取物清除自由基以及鳌合铁离子的能力密切相关。  相似文献   

18.
In the present study, northern whiting fish (Sillago sihama) muscle was hydrolyzed with gastrointestinal enzymes (pepsin, trypsin and α-chymotrypsin) separately and the resulted protein hydrolysates were tested for antioxidant activities using DPPH radical scavenging activity and reducing power assays. The protein hydrolysate obtained from trypsin exhibited highest antioxidant activity. Further, it was fractionated by consecutive chromatography using anion exchange and gel filtration chromatography; the separated fractions were collected and evaluated for antioxidant activity. The results showed that fraction 2 exhibited high chelating activity (73.15 % at 0.5 mg/mL) and best radical scavenging activity for DPPH radical (55.16 % at 0.5 mg/mL), ABTS radical (57.98 % at 50 μg/mL), superoxide radical (39.55 % at 200 μg/mL) and hydroxyl radical (51.33 % at 100 μg/mL). In addition, the active fraction showed strong antioxidant activity in the inhibition of linoleic acid autooxidation (60 % at 0.5 mg/mL) and also it exhibited significant protective effect on DNA damage caused by hydroxyl radicals. The size of the active fraction was found to be <360.2 Da using mass spectroscopy. These results demonstrate that muscle protein hydrolysate from northern whiting fish could be a best alternative to produce natural antioxidant peptides.  相似文献   

19.
Aim and objectiveHippophae rhamnoides is an edible, nutrient rich plant found in the northern regions of India. It belongs to the family Elaeagnaceae and is well known for its traditional pharmacological activities. The present study was aimed to investigate the antioxidant and neuroprotective activities of H. rhamnoides.MethodologyThe hydroalcoholic extract of H. rhamnoides was evaluated for free radical scavenging activity using DPPH, hydroxyl radical scavenging and ferric thiocyanate assays. In vitro neuroprotective activity was assessed on human neuroblastoma cell line-IMR32 against hydrogen peroxide (H2O2) induced cytotoxicity. The neuroprotective effect was determined by measuring the cell viability through tetrazolium dye MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) reducing assay and propidium iodide (PI) staining. Also the intracellular reactive oxygen species (ROS) activity was assessed using dichloro-dihydro-fluorescein diacetate (DCFDA) assay by flowcytometer.ResultsThe results of the study demonstrated that H. rhamnoides extract possesses potential free radical scavenging activity. The IC50 value for DPPH and OH radical scavenging assay was 70.92 μg/ml and 0.463 mg/ml, also the extract was also found to have considerable level of lipid peroxidation activity. The neuroprotective effect of H. rhamnoides was confirmed by its cell viability enhancing capacity against hydrogen peroxide induced cell cytotoxicity. The extract acted on IMR32 cells in a dose dependent manner as observed through PI and MTT assays. The percentage intracellular ROS activity was reduced by 60–70% in treated cells compared to H2O2 control.ConclusionThus the outcome of the study suggests that H. rhamnoides acts as a neuroprotectant against oxidative stress induced neurodegeneration.  相似文献   

20.
Aconitum kusnezoffii Reichb., one of the earliest recorded toxic species of genus Aconitum, has been used as traditional Chinese medicine and medicinal diet over the last 2500 years to treat heart failure congestion, neuralgia, rheumatism and gout, etc. In the present paper, four water-soluble polysaccharide fractions isolated from the tubers of A. kusnezoffii Reichb. were studied the antioxidant and immunological activities for the first time. In vitro antioxidant assays indicated that fraction WKCP-A had noticeable scavenging activities on DPPH radical, hydroxyl radical, superoxide anion, H2O2 and self-oxidation of 1,2,3-phentriol, ferrous ion-chelating ability and reducing power. Moreover, the in vivo immunological assay exhibited that fractions WKCP-A and WKHP could more significantly enhance splenic lymphocyte proliferation and macrophage phagocytosis than other fractions. Therefore, the water-soluble polysaccharides from A. kusnezoffii Reichb., especially WKCP-A, have the potential to be explored as novel natural antioxidants and immunostimulating agents for using in functional foods or medicine.  相似文献   

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