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1.
The antioxidative activities of water extract (WE) and crude hot-water soluble polysaccharide (PS) from Ficus carica L. fruit were investigated using various assays in vitro, including scavenging abilities on DPPH, superoxide and hydroxyl radicals and reducing power. The immunity activities of PS were evaluated using the carbon clearance test and serum hemolysin analysis in mice. In addition, total phenolics and flavonoids contents were also determined. Both WE and PS have notable scavenging activities on DPPH with the EC50 values of 0.72 and 0.61 mg/ml, respectively. The PS showed higher scavenging activity than WE on superoxide radical (EC50, 0.95 mg/ml) and hydroxyl anion radical (scavenging rate 43.4% at concentration of 4 mg/ml). The PS (500 mg/kg) also has a significant increase in the clearance rate of carbon particles and serum hemolysin level of normal mice. The results indicate that both WE and PS might be applicable in healthy medicine and food industry.  相似文献   

2.
In this research, some herbal teas and infusions traditionally used in the treatment of diabetes in Turkey, have been studied for their antidiabetic effects on in vitro glucose diffusion and phenolic contents and antioxidant activities. Ten aqueous herbal tea extracts were examined using an in vitro method to determine their effects on glucose movement across the gastrointestinal tract. Total phenol content of herbal teas was analyzed by Folin–Ciocalteu’s procedure. Antioxidant activities of herbal teas were evaluated by the effect of extracts on DPPH radical and hydrogen peroxide scavenging. Antioxidant activity was defined as the amount of the sample to decrease the initial DPPH· concentration by 50% as efficient concentration, EC50. Antiradical activity [AE] was calculated as 1/EC50. Values were evaluated statistically. Results support the view that none of the herbal teas showed antidiabetic effect on glucose diffusion using in vitro model glucose absorption. Teas were arranged in the order of green tea > peppermint > thyme > black tea > relax tea > absinthium > shrubby blackberry > sage > roselle > olive leaves according to their total phenol contents. Among ten herbal teas, green tea had the highest hydrogen-donating capacity against to DPPH radical. Ranking of the herbal teas with respect to their DPPH radical scavenging activity were green tea > peppermint > black tea > thyme > relax tea > absinthium > roselle > olive leaves > sage > shrubby blackberry. It was determined that adding flavoring substances such as lemon, bergamot, clove and cinnamon, which are commonly used in preparation of black tea in Turkey resulted to have synergistic effect on total antioxidant activities of black and peppermint teas. The highest hydrogen peroxide inhibition value (65.50%) was obtained for green tea at a 250 μl/ml concentration. The H2O2 scavenging activity of herbal teas decreased in the order green tea > peppermint > relax tea > black tea > thyme > olive leaves > sage > absinthium > shrubby blackberry > roselle. In particular, their phenolic compounds and antioxidant activities may be useful for meal planning in type 2 diabetes. They could contribute to sustain plasma antioxidant level because antioxidants present in plants and herbs prevent the development of vascular diseases seen in type 2 diabetes.  相似文献   

3.
The scavenging activity against DPPH (1,1-diphenil-2-picrylhydrazyl) radical and the antifungal effect against chloroform, ethyl acetate and 50% methanolic extracts of Verbena officinalis leaves were investigated. The activity of different fractions of 50% methanolic extract and some isolated compounds were also investigated. The results suggest that 50% methanolic extract and caffeoyl derivatives could potentially be considered as excellent and readily available sources of natural antifungal and antioxidant compounds.  相似文献   

4.
Organic solvent (methanol, ethanol, and acetone) extracts and water extracts of cherry (Prunus serrulata var. spontanea) blossoms were prepared, and antioxidant activities of the extracts were evaluated. Methanolic CBE (100 μg/ml) showed the highest total phenol content (104.30 μM), radical scavenging activity (34.2%), and reducing power (0.391). The effect of CBE on DNA damage induced by H2O2 in human leukocytes was evaluated by Comet assay. All CBE was a potent dose dependent inhibitor of DNA damage induced by 200 μM of H2O2, methanolic CBE showed the most strong inhibition activity. The methanolic CBE of 500 μg/ml showed 38.8% inhibition against growth of human colon cancer cell line HT-29. These results indicated that cherry blossoms could provide valuable bioactive materials.  相似文献   

5.
Edible fruits of the native South American tree Melicoccus bijugatus Jacq. are consumed fresh or in traditional food, drink and medicinal preparations. Some therapeutic effects of these fruits may be due to phenolics and sugars. Aqueous acetone, methanol or ethanol tissue extracts of different cultivars or collections of M. bijugatus fruits from the Dominican Republic and Florida were analyzed for total phenolics and free radical scavenging activity by UV-vis spectroscopy, sugars by gas chromatography, and antimicrobial activity by the disc diffusion assay. Total phenolics and free radical scavenging activities ranked: seed coat > embryo > pulp extracts. Montgomery cultivar fruits had the highest total phenolics. For sugars: pulp > embryo and highest in Punta Cana fruit pulp. In all extracts: sucrose > glucose and fructose. Glucose:fructose ratios were 1:1 (pulp) and 0.2:1 (embryo). Pulp extracts had dose-response antibacterial activity and pulp and embryo extracts had antifungal activity against one yeast species. Phenolics and sugars were confirmed with thin-layer chromatography and nuclear magnetic resonance. Sugar-free pulp fractions containing phenolics had slightly more antimicrobial activity than H2O-soluble pulp fractions with sugars. Results indicate M. bijugatus fruits contain phenolics, sugars and other H2O-soluble compounds consistent with therapeutic uses. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

6.
The antioxidant activity in 70% aqueous acetone extracts of the herb of Ambrosia artemisiifolia L., Asteraceae was evaluated with regards to total polyphenol and flavonoid contents. Antioxidant activity has been assessed by two commonly used in vitro tests, based on determination of ferric-reducing antioxidant power (FRAP assay) and DPPH free radical scavenging ability (DPPH assay), against butylated hydroxytoluene (BHT), ascorbic acid and quercetin, which were used as positive control substances. The results of both antioxidant tests showed that the plant material expressed a considerable activity (DPPH IC50 = 27.6 μg/ml; FRAP value = 2.37 mmol Fe2+/g), attributed to both flavonoid aglyca and resembling glycosides, as verified by dot-blot TLC analysis.  相似文献   

7.
Water and methanol extracts from roots of Ozoroa paniculosa (Anarcardiaceae); seeds of Colophospermum mopane (Caesalpiniaceae) and Cucumis metuliferus (Cucurbitaceae) ripe fruits were assessed for in vitro antioxidant activity. Free radical scavenging activity was measured spectrophotometrically as maximum fading power of DPPH at 525 nm. Water and methanol extracts of Ozoroa paniculosa exhibited higher scavenging potency than extracts of either Colophospermum mopane or Cucumis metuliferus at all tested concentrations. None of the extracts from Cucumis metuliferus exhibited any recognizable free radical scavenging activity. Above 50 microg mL(-1) both water and methanol extracts of Ozoroa paniculosa exhibited 91% scavenging activity similar to the control compounds L-ascorbic acid (91%) and (-) epicatechin (92%). Between 50-100 microg mL(-1), water and methanol extracts of Colophospermum mopane exhibited scavenging potency of < or = 70%. However, above 100 microg mL(-1), both water and methanolic extracts of C. mopane exhibited scavenging activity > 70%. Chloroform extracts of all the tested plants showed poor scavenging activity (< 30%). The order of scavenging potency for the tested samples was as follows: L-ascorbic acid > or = epicatechin > O. paniculosa (methanolic extract) > O. paniculosa (water extract) > O. paniculosa (ethylacetate extract) > C. mopane (methanolic extract) > C. mopane (water extract) > all extracts of C. metuliferus. These findings lend credence to the use of these plants as anti-inflammatory and antioxidant agents in folk medicine.  相似文献   

8.
Background:Levan or fructan, a polysaccharide of fructose, is widely used in various commercial industries. Levan could be produced by many organisms, including plants and bacteria. The cloning of the gene from Bacillus licheniformis, which expressed levansucrase in Escherichia coli host, was carried out successfully. In the present study, we performed the in vitro production of levan and analyzed its potential application as antibacterial and antioxidant agents. Methods: In vitro levan production catalyzed by heterologous-expressed levansucrase Lsbl-bk1 and Lsbl-bk2 was optimized with BW design. The antibacterial activity of the produced levan was carried out using agar well diffusion method, while its antioxidant activity was tested by free radical scavenging assays. Results:The optimum conditions for levan production were observed at 36 °C and pH 7 in 12% (w/v) sucrose for levansucrase Lsbl-bk1, while the optimum catalysis of levansucrase Lsbl-bk2 was obtained at 32 oC and pH 8 in the same sucrose concentration. The in vitro synthesized levan showed an antibacterial activity within a concentration range of 10-20% (w/v) against Staphylococcus aureus, E. coli, and Pseudomonas aeruginosa. The same levan was also able to inhibit the DPPH radical scavenging activity with the antioxidant strength of 75% compared to ascorbic acid inhibition. Conclusion:Our study, therefore, shows that the optimized heterologous expression of levansucrases encoded by Lsbl-bk1 and Lsbl-bk2 could open the way for industrial levan production as an antibacterial and antioxidant agent. Key Words: Antioxidants, Fructans, In vitro technique, Levan  相似文献   

9.
    为了优化磷酸化改性花生分离蛋白-多肽膜制备工艺条件,在单因素基础上,通过响应面Box-Benhnken进行实验设计。结果表明,最优工艺参数:蛋白浓度8%、pH值8.2、甘油百分含量(占蛋白)13.4%、黄原胶百分含量(占蛋白)1%、时间60min、温度69℃、超声波功率270W、超声波频率28kHz、多肽溶液的浓度61mg/mL;此工艺条件下,膜厚度、吸水率和透光率理论预测值分别为86μm、41.9%和53.6%,验证实验值分别为88±2μm、43.1±1.2%和52.4±1.5%,两者的差值分别为2.33%、2.86%和2.24%,说明响应面二次模型的拟合良好;磷酸化改性花生分离蛋白-多肽膜的抗拉强度9.62MPa、断裂延伸率101.68%、溶解性47.69%、水蒸气透过率6.95 g•m-2· h-1等功能性质和DPPH自由基清除活性IC50值7.70 mg·mL-1、羟自由基清除活性IC50值5.98 mg·mL-1、超氧阴离子自由基清除活性IC50值4.20 mg·mL-1、铁离子螯合力活性IC50值3.79 mg·mL-1、铜离子螯合力活性IC50值13.61 mg·mL-1、脂质过氧化抑制活性IC50值8.62 mg·mL-1、铁还原力IC50值13.93mg·mL-1、钼还原力IC50值5.49mg·mL-1等抗氧化活性较磷酸化改性花生分离蛋白膜有所改善。本研究结果为磷酸化改性花生分离蛋白在蛋白膜方面的应用提供一种新途径。  相似文献   

10.
Sunflower seed meal peptide as one sort of bioactive peptide has intensively application prospects. However, preparation of low salt peptide from sunflower seed meal with high efficiency remains a challenge. In this study, single and compound proteases were optimized to hydrolyze protein. Results showed that hydrolysis at pH 7.0 by proteases resulted in ash content in the range of 5.66%-7.37% and small peptides. Among all hydrolysis processes, sequential hydrolysis of Alcalase with Flavourzyme and Alcalase with Protamex showed higher nitrogen recovery ratio (67.66% and 66.49%, respectively). Furthermore, biological activities of peptides were investigated by testing their ABTS (2,2-azinobis (3-ethylben-zothiazoline-6-sulfonic acid) diammonium salt) radical scavenging activity, DPPH (2,2-diphenyl-1-picrylhydrazil) radical scavenging activity and angiotensin converting enzyme (ACE) inhibitory activity. Peptide hydrolyzed by Alcalase with Papain presented the highest antioxidant activity, followed by Alcalase with Protamex, with ABTS scavenging rate as 63.01% and 31.75%, and DPPH scavenging rate as 56.04% and 28.06%, respectively. Synchronously, peptide hydrolyzed by Alcalase with Protamex and Alcalase with Alcalase had the highest ACE inhibitory activity (56.74%, 56.76%). In conclusion, hydrolysis by proteases Alcalase with Protamex at pH 7.0 was the most effective method for the preparation of low salt peptide from sunflower seed meal, which could be an alternative for anti-oxidants and anti-vasoconstrictor.  相似文献   

11.
The cell wall components and the food functions of alcohol-insoluble solids (AIS) of Chinese quince, quince, hawthorn, apple, pear and blueberry fruits were analyzed. Chinese quince contained characteristically high contents of cellulose, lignin, and non-extractable procyanidins (NEPCs). On the other hand, the quince AIS contained the highest proportion of NEPCs, the highest mean degree of polymerization (mDP), the strongest radical scavenging activity, and strong bile acid binding activity. In fruit AIS, the lignin and NEPC contents both showed positive correlations with the bile acid binding and radical scavenging activities. The value for mDP × NEPC content was a good index for the radical scavenging activity. The results suggest that highly polymerized NEPCs and lignin are important factors of cell wall components of fruits to having a high functionality, and Chinese quince and quince are interesting fruits from this view point.  相似文献   

12.
Hemp seed protein hydrolysate (HPH) was produced through simulated gastrointestinal tract (GIT) digestion of hemp seed protein isolate followed by partial purification and separation into eight peptide fractions by reverse-phase (RP)-HPLC. The peptide fractions exhibited higher oxygen radical absorbance capacity as well as scavenging of 2,2-diphenyl-1-picrylhydrazyl, superoxide and hydroxyl radicals when compared to HPH. Radical scavenging activities of the fractionated peptides increased as content of hydrophobic amino acids or elution time was increased, with the exception of hydroxyl radical scavenging that showed decreased trend. Glutathione (GSH), HPH and the RP-HPLC peptide fractions possessed low ferric ion reducing ability but all had strong (>60 %) metal chelating activities. Inhibition of linoleic acid oxidation by some of the HPH peptide fractions was higher at 1 mg/ml when compared to that observed at 0.1 mg/ml peptide concentration. Peptide separation resulted in higher concentration of some hydrophobic amino acids (especially proline, leucine and isoleucine) in the fractions (mainly F5 and F8) when compared to HPH. The elution time-dependent increased concentrations of the hydrophobic amino acids coupled with decreased levels of positively charged amino acids may have been responsible for the significantly higher (p?<?0.05) antioxidant properties observed for some of the peptide fractions when compared to the unfractionated HPH. In conclusion, the antioxidant activity of HPH after simulated GIT digestion is mainly influenced by the amino acid composition of some of its peptides.  相似文献   

13.
Betalains are water-soluble plant pigments that are widely used as food colorants, and have a wide range of desirable biological activities, including antioxidant, anti-inflammatory, hepatoprotective, anti-cancer properties. They can be produced from various plants, notably beetroot, but betalain products obtained in this way also have some undesirable properties and are difficult to standardize. A potentially attractive alternative is to use hairy root cultures. In the study reported here, we found that betalain extracts obtained from hairy root cultures of the red beetroot B. vulgaris cv. Detroit Dark Red also had higher antioxidant activity than extracts obtained from mature beetroots: six-fold higher 2,2-dyphenyl-1-picrylhydrazyl radical scavenging ability (90.7% inhibition, EC50 = 0.11 mg, vs 14.2% inhibition, EC50 = 0.70 mg) and 3.28-fold higher oxygen radical absorbance capacity (4,100 μM TE/g dry extract, vs 1,250 μM TE/g dry extract). The high antioxidant activity of the hairy root extracts was associated with increased concentrations (more than 20-fold) of total phenolic concomitant compounds, which may have synergistic effects with betalains. The presence of 4-hydroxybenzoic acid, caffeic acid, catechin hydrate, and epicatechin were detected in both types of extract, but at different concentrations. Rutin was only present at high concentration (1.096 mg.g−1 dry extract) in betalain extracts from the hairy root cultures, whereas chlorogenic acid was only detected at measurable concentrations in extracts from intact plants.  相似文献   

14.
Antioxidants play an important role in inhibiting and scavenging free radicals, thus providing protection to human against infections and degenerative diseases. Current research is now directed towards natural antioxidants originated from plants due to safe therapeutics. Moringa oleifera is used in Indian traditional medicine for a wide range of various ailments. To understand the mechanism of pharmacological actions, antioxidant properties of the Moringa oleifera leaf extracts were tested in two stages of maturity using standard in vitro models. The successive aqueous extract of Moringa oleifera exhibited strong scavenging effect on 2, 2-diphenyl-2-picryl hydrazyl (DPPH) free radical, superoxide, nitric oxide radical and inhibition of lipid per oxidation. The free radical scavenging effect of Moringa oleifera leaf extract was comparable with that of the reference antioxidants. The data obtained in the present study suggests that the extracts of Moringa oleifera both mature and tender leaves have potent antioxidant activity against free radicals, prevent oxidative damage to major biomolecules and afford significant protection against oxidative damage.  相似文献   

15.
In this study, the stable collagen hydrolysate was prepared by alcalase hydrolysis and twice simulated gastrointestinal digestion from Alaska pollock skin. The characteristics of hydrolysates and antioxidant activities in vitro, including 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS•+) scavenging activity, ferric-reducing antioxidant power (FRAP) and hydroxyl radical (OH·) scavenging activity, were determined. After twice simulated gastrointestinal digestion of skin collagen (SGI-2), the degree of hydrolysis (DH) reached 26.17%. The main molecular weight fractions of SGI-2 were 1026.26 and 640.53 Da, accounting for 59.49% and 18.34%, respectively. Amino acid composition analysis showed that SGI-2 had high content of total hydrophobic amino acid (307.98/1000). With the simulated gastrointestinal digestion progressing, the antioxidant activities increased significantly (p < 0.05). SGI-2 was further purified by gel filtration chromatography, ion exchange chromatography and high performance liquid chromatography, and the A1a3c–p fraction with high hydroxyl radical scavenging activity (IC50 = 7.63 μg/mL) was obtained. The molecular weights and amino acid sequences of key peptides of A1a3c–p were analyzed using high resolution mass spectrometry (LC-ESI-LTQ-Orbitrap-MS) combined with de novo software and UniProt of MaxQuant software. Four peptides were identified from A1a3c–p, including YGCC (444.1137 Da) and DSSCSG (554.1642 Da) identified by de novo software and NNAEYYK (900.3978 Da) and PAGNVR (612.3344 Da) identified by UniProt of MaxQuant software. The molecular weights and amino acid sequences of four peptides were in accordance with the features of antioxidant peptides. The results indicated that different peptides were identified by different data analysis software according to spectrometry mass data. Considering the complexity of LC-ESI-LTQ-Orbitrap-MS, it was necessary to use the different methods to identify the key peptides from protein hydrolysates.  相似文献   

16.
原生态椰子油体外抗氧化活性   总被引:6,自引:3,他引:3  
对原生态椰子油(VCO)的体外抗氧化活性进行了评价,分析了VCO中总酚酸的含量及其对DPPH自由基和ABTS+自由基的清除能力,对Fe~(2+)的络合能力以及对花生油的抗氧化能力.结果表明,VCO中总酚酸的含量为(0.180±0.003)mg/mL;对DPPH自由基的清除率为31.95%.低于Trolox、BHT和没食子酸;对ABTS~+自由基的清除能力为67.49 μmol/L Tmlox当量(TEAC值);对Fe~(2+)的络合能力优于Tmlox和BHT,但显著低于没食子酸;VCO对花生油具有一定的抗氧化能力.  相似文献   

17.
An activity-directed fractionation and purification process was used to identify the nitric oxide (NO) scavenging components of Phyllanthus emblica. Dried fruit rind of P. emblica was extracted with methanol and then separated into hexane, ethyl acetate, and water fractions. Among these only the ethyl acetate phase showed strong NO scavenging activity in vitro, when compared with water and hexane phases. The ethyl acetate fraction was then subjected to separation and purification using Sephadex LH-20 chromatography. Five compounds showing strong NO scavenging activity were identified by spectral methods (1H NMR, 13C NMR, and MS) and by comparison with literature values to be Gallic acid, Methyl gallate, Corilagin, Furosin, and Geraniin. In addition, HPLC identification and quantification of isolated compounds were also performed. Gallic acid was found to be a major compound in the ethyl acetate extract and Geraniin showed highest NO scavenging activity among the isolated compounds.  相似文献   

18.
Quinoa protein concentrate (QPC) was extracted and digested under in vitro gastrointestinal conditions. The protein content of QPC was in the range between 52.40 and 65.01% depending on the assay used. Quinoa proteins were almost completely hydrolyzed by pepsin at pH of 1.2, 2.0, and 3.2. At high pH, only partial hydrolysis was observed. During the duodenal phase, no intact proteins were visible, indicating their susceptibility to the in vitro simulated digestive conditions. Zebrafish larvae model was used to evaluate the in vivo ability of gastrointestinal digests to inhibit lipid peroxidation. Gastric digestion at pH 1.2 showed the highest lipid peroxidation inhibition percentage (75.15%). The lipid peroxidation activity increased after the duodenal phase. The digest obtained at the end of the digestive process showed an inhibition percentage of 82.10%, comparable to that showed when using BHT as positive control (87.13%).  相似文献   

19.
The effect of thermal and ultrasonic treatment of cowpea proteins (CP) on amino acid composition, radical scavenging and reducing potential of hydrolysates (CPH) obtained from in vitro simulated gastrointestinal digestion of CP was evaluated. Hydrolysis of native and treated CP with gastrointestinal pepsin and pancreatin yielded CPH that displayed antioxidant activities based on oxygen radical scavenging capacity (ORAC), ferric reducing antioxidant power (FRAP) and superoxide radical scavenging activity (SRSA). CPH derived from the treated CP yielded higher ORAC values than CPH from untreated proteins. However, lower significant FRAP and SRSA values were observed for these samples compared to untreated CPH (p?<?0.05). Amino acid analysis indicated that CP processing decreased total sulphur-containing amino acids in the hydrolysates, particularly cysteine. The amount of cysteine appeared to be positively related to FRAP and SRSA values of CPH samples, but not ORAC. The results indicated that thermal and ultrasonic processing of CP can reduce the radical scavenging and reducing potential of the enzymatic hydrolysates possibly due to the decreased amounts of cysteine. Since the hydrolysates were generated with gastrointestinal enzymes, it is possible that the resulting compounds are produced to exert some health functions during normal consumption of cowpea.  相似文献   

20.
槟榔红色素的抗氧化活性   总被引:2,自引:1,他引:1  
测定槟榔红色素(areca red pigment,AP)对 DPPH·和·OH的清除能力、对脂质体过氧化的抑制能力、对Fe2+的络合能力,并测定其还原能力.结果表明:槟榔色素对DPPH·、·OH的清除能力较强:对脂质体过氧化的抑制能力很强,抑制率高达79.84%;与VE、没食子酸(gallic acid,GA)、BHT相比,槟榔色素的还原力、对Fe2+的络合能力较弱.说明槟榔红色素是较好的抗氧化剂.  相似文献   

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