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Objective: To develop a novel method to synthesize silver nanoparticles (AgNPs) by using the extract of Yinqiao Jiedu Mixture waste, evaluate the effects of biosynthesis parameters on the formation and polydispersity of AgNPs, and investigate the antioxidative and antibacterial activity. Methods: The formation of AgNPs was confirmed by UV-visible spectroscopy; The size, polydispersity, surface and morphology features of AgNPs were characterized by laser granularity analyzer and transmission electron microscopy; The antioxidative and antibacterial activities of AgNPs were evaluated by calculating the scavenging rate for DPPH and A600 for both Escherichia coli and Staphylococcus aureus, respectively. Results: By using Yinqiao Jiedu Mixture waste, the AgNPs could be prepared at ambient temperature. The size and polydispersity index of the synthesized AgNPs were sensitive to the biosynthesis parameters, such as pH of extract and material proportion with the average size distribution was 14.2-94.8 nm, offering a size-controlled synthetic method for AgNPs. And when the pH was 6.0, the polydispersity could reach the best. The AgNPs could be obtained with high yield and small size at pH 10.0, material proportion 3:1 after reacting 2 h, which were quasi-spherical in shape with average size of (24.0 ± 0.3) nm and covered by anion [Zeta potential: (-23.1 ± 0.2) mV]. The synthesized AgNPs also revealed significant inhibition activities for the growth of E. coli and S. aureus with MIC 50.0 and 25.0 μg/mL, respectively, and potent antioxidative activity with scavenging rate for DPPH 71.1% when adding 100 μg/mL of AgNPs. Conclusion: The extract of Yinqiao Jiedu Mixture waste can be used to synthesize AgNPs with small size at ambient temperature; The biosynthesis parameters have significant effects on the average size and polydispersity index of AgNPs; The synthesized AgNPs have potent antioxidative and antibacterial activity.
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Flavonoid is one of the important natural compounds in Polygonatum genus. A total of 54 compounds of six different structural subtypes have been isolated from eight species of Polygonatum genus. Recent studies have shown that the flavonoid compounds of Polygonatum genus have various bioactivities, including hypoglycemic, anti-inflammatory, anti-oxidative, and antitumor. This study reviewed different structural categories of flavonoids from Polygonatum genus and their pharmacological effects. This work will provide a scientific reference for the further research on flavonoids in Polygonatum genus.
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To study the chemical constituents of Ledum palustre. Methods Compounds were isolated from n-hexane fraction in the ethanol extract from L. palustre by silica gel column chromatography and HPLC. The structures of the chemical constituents were identified by analysis on their spectral data. Results Fourteen compounds were isolated from EtOAc fraction in the ethanol extract from L. palustre and identified as resveratorol (1), moracin M (2), catechin (3), epicatechin (4), scopoletin (5), esculetin (6), fraxetin (7), 5-hydroxy-2methoxybenzoic acid (8), fraxidin (9), 2α,3α-epoxy-5,7,3’,4’-tetrahydroxyflavan-(4β-8)-epicatechin (10), 2α,3α-epoxy-5,7,3’,4’-tetrahydroxyflavan-(4β-8-catechin) (11), cleomiscosin A (12), cleomiscosin C (13), and isofraxoside (14). Conclusion Compounds 1, 2, and 8-13 are obtained from the plants of Ledum L. for the first time. Compounds 3, 4, 6, 7, 10, and 11 had significant anti-oxidative activities.
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Objective: To evaluate the essential oils (EO) composition, antimicrobial and antioxidant power of a local plant, Daucus gracilis (D. gracilis). Methods: The aerial parts of D. gracilis were subjected to hydro distillation by a Clevenger apparatus type to obtain the EO which had been analyzed by gas chromatography and gas chromatography coupled with mass spectrometry, and screened for antimicrobial activity against five bacteria and three fungi by agar diffusion method. The mechanism of action of the EO was determined on the susceptible strains by both of time kill assay and lysis experience. The minimal inhibitory concentrations were determined by agar macro-dilution and micro-dilution methods. Anti-oxidative properties of the EO were also studied by free diphenyl-2-picrylhydrazyl radical scavenging and reducing power techniques. Results: The EO yielded 0.68 (v/w). The chemical analysis presented two dominant constituents which were the elemicin (35.3%) and the geranyl acetate (26.8%). D. gracilis EO inhibited the growth of Bacillus cereus and Proteus mirabilis significantly with minimal inhibitory concentrations of 17.15 μg/mL by the agar dilution method and 57.05 μg/mL and 114.1 μg/mL, respectively by liquid micro-dilution. A remarkable decrease in a survival rate as well as in the absorbance in 260 nm was recorded, which suggested that the cytoplasm membrane was one of the targets of the EO. The EO showed, also, important anti-oxidative effects with an IC
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Objective: To evaluate the essential oils (EO) composition, antimicrobial and antioxi-dant power of a local plant, Daucus gracilis (D. gracilis). Methods: The aerial parts of D. gracilis were subjected to hydro distillation by a Cle-venger apparatus type to obtain the EO which had been analyzed by gas chromatography and gas chromatography coupled with mass spectrometry, and screened for antimicrobial activity against five bacteria and three fungi by agar diffusion method. The mechanism of action of the EO was determined on the susceptible strains by both of time kill assay and lysis experience. The minimal inhibitory concentrations were determined by agar macro-dilution and micro-dilution methods. Anti-oxidative properties of the EO were also studied by free diphenyl-2-picrylhydrazyl radical scavenging and reducing power techniques. Results: The EO yielded 0.68 (v/w). The chemical analysis presented two dominant constituents which were the elemicin (35.3%) and the geranyl acetate (26.8%). D. gracilis EO inhibited the growth of Bacillus cereus and Proteus mirabilis significantly with minimal inhibitory concentrations of 17.15 mg/mL by the agar dilution method and 57.05 mg/mL and 114.1 mg/mL, respectively by liquid micro-dilution. A remarkable decrease in a survival rate as well as in the absorbance in 260 nm was recorded, which suggested that the cytoplasm membrane was one of the targets of the EO. The EO showed, also, important anti-oxidative effects with an IC50 of 0.002 mg/mL and a dose-dependent reducing power. Conclusions: D. gracilis EO showed potent antimicrobial and anti-oxidative activities and had acted on the cytoplasm membrane. These activities could be exploited in the food industry for food preservation.
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Objective: To isolate, purify, and analyze the anti-oxidants from the leaves of Lantana trifolia. Methods: The anti-oxidative activities of the crude extracts from liquid-liquid extraction of L. trifolia leaves were assayed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) method to assess their radical scavenging and reducing abilities. The total flavonoids and phenol contents in the ethyl acetate fraction were determined by colorimetric and Folin-Ciocalteu methods, respectively. Chemical constituents were isolated from the ethyl acetate fraction and repeatedly purified using silica gel, Sephadex LH-20 column chromatography, and HPLC, respectively. The chemical structures isolated were identified by spectral analysis and chemical evidence. Results: Ethyl acetate partition from liquid-liquid extraction exhibited the highest anti-oxidative activity with an IC50 value of 4.94 μg/mL, close to that of the standard (vitamin C, VC, 4.23 μg/mL). The extract was proved to contain total flavonoids and phenol contents with values of (39.0 ± 1.6) and (29.27 ± 1.46) mg/g, respectively. Six compounds were isolated and identified as kaempferol-3,7-dimethyl ether (1), verbascoside (2), apigenin (3), umuhengerin (4), ladanetin (5), and scutellarein-7-O-β-D-apiofuranoside (6). Conclusion: The ethyl acetate extract from the leaves of L. trifolia possesses the potent anti-oxidative and free radical scavenging activities which are directly proportional to the concentration of phenolic contents. The anti-oxidative activity of the extract from the leaves of L. trifolia is due to its proton donating ability that converts free radicals to more stable products and terminates chain reactions. Compound 1 is isolated from the plants of Lantana Linn. for the first time. The mechanisms may be related to the therapeutic benefits of the certain traditional claims of wild L. trifolia. © 2014 Tianjin Press of Chinese Herbal Medicines.
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Objective: To evaluate the content of rhaponticin and anti-oxidative activities of the ethanol extracts from both the wild plants and suspension cell cultures of Rheum franzenbachii. Methods: Quantitative analysis of rhaponticin was performed by HPLC. The anti-oxidative activities of the ethanol extracts were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assays. Results: The content of rhaponticin in the roots of the wild plant was 4.36 mg/g, while the content was only 1.59 mg/g in the leaves. The content of rhaponticin in suspension cells cultured on Murashige and Skoog (MS) medium supplemented with 1.0 mg/L 6-benzylaminopurine (6-BAP) and 2.0 mg/L 2,4-dicholorophenoxy acetic acid (2,4-D) was 17.64 mg/g, which increased by 4.05 times compared with the content in the roots of the wild plants. The roots of wild plants displayed the strongest anti-oxidative activity, followed by the suspension cells 5 and 6, and the scavenging percent was 91.96%, 91.23%, and 89.27%, respectively, at the concentration of 100 μg/mL. The IC50 values were 2.477, 15.644, and 31.415 μg/mL, respectively. In particular, the DPPH scavenging activity of the ethanol extracts from the roots of the wild plant was generally comparable to the control of ascorbic acid (VC), and the IC50 value of the extracts was lower than that of VC (2.502 μg/mL). Conclusion: Rhaponticin production in the cell culture can be modulated and the accumulation can be increased. The roots of the wild plant display the strongest anti-oxidative activity. These results suggest that R. franzenbachii could hold a good potential source for human health. © 2014 Tianjin Press of Chinese Herbal Medicines.
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Objective: To study the chemical compositions from the root tuber of Tetrastigma hemsleyanum and their anti-oxidative activities. Methods: The compounds were isolated by various column chromatography. Their structures were identified by spectroscopic methods including 1H-NMR, 13C-NMR, MS, HR-MS, etc. The anti-oxidative activities were evaluated by DPPH radical scavenging assay. Results: Fourteen compounds were isolated from the root tuber of T. hemsleyanum, they were identified as kaempferol (1), quercetin (2), salicylic acid (3), benzoic acid (4), oxyresveratrol (5), catechin (6), L-epicatechin (7), epigallocatechin (8), procyanidin B2 (9), procyanidin B1 (10), 3-O-caffeoylquinic acid (11), protocatechualdehyde (12), p-hydroxybenzoic acid (13), and protocatechuic acid (14). The anti-oxidative IC50 values of compounds 2, 8, 9, 10, and 12 were 14.15, 14.19, 15.99, 12.4, and 15.98 μmol/L, respectively, better than the positive control Vit C (IC50 value was 23.0 μmol/L). Conclusion: Compounds 4-12 are isolated from T. hemsleyanum for the first time. It has been demonstrated that the root tuber contain flavonoids and also is rich in organic acids. Moreover, compounds 2, 8, 9, 10, and 12 have the certain prospects in the development of natural anti-oxidative agents.
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Objective: To study the chemical constituents from the roots of Astragalus englerianus, and to determine their anti-oxidative activities. Methods: The compounds were isolated and purified by silica gel, RP18, and Sephadex LH-20 column chromatography, then their structures were elucidated on the basis of spectral data and physicochemical properties, and anti-oxidative activities were tested by DPPH method. Results: Twenty-nine compounds were obtained from the ethyl acetate fraction of the methanol extract from the roots of A. englerianus and identified as isoliquiritigenin (1), 4'-hydroxy-2, 4-dimethoxychalcone (2), xenognosin (3), formononetin (4), calycosin (5), prunetin (6), (3R)-vestitol (7), liquiritigenin (8), (6aR, 11aR)-medicarpin-3-O-β-D-glucopyranoside (9), olean-12-en-3β, 22β, 24-triol (10), friedelin (11), β-sitosterol (12), stigmasterol (13), 7β-hydroxysitosterol (14), 7-oxositosterol (15), 3β-sitosteryl (9'Z)-9'-heptadecenoate (16), stigmast-4-en-3-one (17), 5α, 8α-epidioxy-ergosta-6, 9, 22E-trien-3β-ol (18), 5α, 8α-epidioxy-ergosta-6, 22E-dien-3β-ol (19), D-2-O-methylinositol (20), octacosanol (21), methyl stearate (22), eicosanoic acid (23), heneicosanoic acid (24), oleic acid (25), linoleic acid (26), α-linolenic acid (27), tripalmitin (28), and trilinolein (29). The ethyl acetate soluble portion, compounds 1 and 3 showed DPPH free radical scavenging activity with IC50 values of (66.0 ± 1.8), (64.3 ± 0.4), and (57.1 ± 1.2) μg/mL, respectively. Conclusion: This is the first report on the compounds 2, 3, 6, 10, 11, 14-22, and 28 from the plants of Astragalus Linn., and all the compounds are obtained from A. englerianus for the first time. A. englerianus is found to possess the potent anti-oxidative activity.
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Objective: To study the chemical constituents with anti-oxidative activity from the fruits of Illicium micranthum. Methods: DPPH Radical scavenging assay was used for screening the active fractions. The chemical constituents were isolated and purified by various column chromatographic methods such as silica gel and Sephadex LH-20. The structures were identified by physicochemical properties and spectral analyses. Results: The ethyl acetate layer of methanol extract from the fruits of I. micranthum showed anti-oxidative activity, from which 14 compounds were separated. Their structures were identified as gynurenol (1), β-elemol (2), epi-carrisone (3), 6-hydroxy-eudesm-4(14)-ene (4), β-eudesmol (5), trans-eudesmane-4, 11-diol (6), 1R, 2R, 4R-trihydroxy-p-menthane (7), 2-isopropenyl-5-methyl-cyclohexanol (8), (-)-isopulegol (9), 4-isopropenyl-1-methyl-cyclohexanol (10), palmitic acid (11), triacontanoic acid (12), p-hydroxy-benzoic acid (13), and β-daucosterol (14). Conclusion: Except for compound 14, all the other compounds are isolated from the fruits of I. micranthum for the first time, while compounds 1-4, 7, and 8 are isolated from the plants in Illiciaceae family for the first time.
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Objective: To explore the production and properties of matallothionein (MT) in Cordyceps kyusyuensis under the zinc ion (Zn2+) stress. Methods: By adding ZnSO4 to the culture, the production regularity of MT in C. kyusyuensis under Zn2+ stress was explored. Ultrasonic cell disruption, crude extraction, and gel column chromatography were employed to isolate and purify the MT. The methods of Coomassie brilliant blue, electron spray mass spectrometry (ESMS), Ellman's reagent colorimetry, atomic flame absorption spectrometry, silver saturation method with atomic absorption spectrometry analysis, and amino acid analyzer were used to determine the purity, molecular weight, sulfhydryl content, zinc content, MT content, and amino acid composition, respectively. In addition, the anti-oxidative activity was identified by scavenging capacity of hydroxyl radicals (HO·), DPPH radicals (DPPH·), and superoxide anion radicals (O2·̄). Results: The contents of Zn and MT in mycelia increased strikingly with the increase of Zn2+ concentration (0-15 g/L) in the culture medium. In 10 L fermenter, MT achieved the maximum yield up to 14.335 mg/g mycelium (wet weight) with Zn concentration of 15 g/L in 56 h, and the biomass reached 16.921 g/L. The C. kyusyuensis Zn-MT was obtained with Sephadex G-50 and Sephadex G-25 gel filtration, and dried by vacuum freeze-drying. The molecular weight of the protein was 6 750, one molecule Zn-MT binded six zinc atoms and contained 56 molecules of amino acid, which contained 20 molecules of cysteine and one molecule of histidine. The eliminating action of C. kyusyuensis Zn-MT for HO·, DPPH·, and O2·̄ was better than that of glutathione, and the eliminating action was different in O2·̄ > DPPH· > HO·. The concentration of half clearance rate was 71.49, 80.58, and 100.65 mg/L. Conclusion: According to ultraviolet scan pattern analysis, protein column chromatogram analysis, physicochemical properties, and anti-oxidative activity of C. kyusyuensis Zn-MT, it is similar with the characteristics of standard animal MT, and a certain concentration of zinc sulfate liquid fermentation of C. kyusyuensis could induce the synthesis of Zn-MT, which could provide the reliable theoretical basis for the industrial production.
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Ipomoea imperati (Vahl) Griseb., Convolvulaceae, is used in traditional medicine for the treatment of inflammation, swelling and wounds, as well as to treat pains and stomach problems. This work evaluates the anti-oxidative activity by ESR (Electron Spin Resonance spectroscopy) and the preventive and curative actions of I. imperati in gastric ulcer animal model. Ipomoea imperati (200 mg/kg, p.o.) prevented the formation of gastric lesions in 78 percent (p<0.05) when compared with the negative control tween 80. Lanzoprazole, prevented in 85 percent the gastric lesions formation induced by ethanol (p<0.05). Therefore, the oral administration of I. imperati one hour before the ulcerogenic agent prevented the ulcer formation, conserving the citoprotection characteristics of the gastric mucosa and assuring the integrity of gastric glands and gastric fossets. The healing activity of I. imperati (200 mg/kg, p.o.) evaluated in chronic ulcer experiments induced by the acetic acid, was 72 percent (p<0.05). The positive control, ranitidine, healed 78 percent of the gastric lesions (p<0.05). The histological analysis confirmed the recovery of the mucosal layer and the muscle mucosal layer harmed by the acetic acid. Experiments in vitro with DPPH (2.2-diphenyl-1-picrylhydrazyl) of anti-oxidative activity demonstrated that I. imperati presents an IC50 of 0.73±0.01 mg/mL.
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Objective: To select the proper method for extracting flavonoids from Cajanus cajan leaves and optimize the extraction parameters. Methods: Taking the extracting rate of orientoside, luteolin, and total flavonoids from C. cajan leaves and anti-oxidative activity as indexes, microwave-assisted method was compared with heat reflux extraction, ultrasound-assisted extraction, and maceration extraction. Central composite design was used for optimization of parameters affecting the extraction of orientoside and luteolin using microwave-assisted method. Results: The results showed that microwave-assisted extraction was the best method and the optimal conditions were: 50 mesh particle size, 80% ethanol aqueous, 1 : 20 material/ethanol aqueous, temperature 60°C, 4 times cycle, 10 min extraction time, 500 W extraction power. The extraction yields of orientoside and luteolin were (4.42 ± 0.01) and (0.10 ± 0.01) mg/g from dry C. cajan leaves, respectively. Conclusion: The microwave-assisted method is feasible with less time, higher extraction yield, and better anti-oxidative activity.
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Objective To explore the effects of a potential anti-oxidative plant,Erigeron multiradiatus(Asteraceae),plant materials from naturally distributed high-altitude populations at different stages of life cycle were collected.Methods Fifteen extracts obtained from the Ganzi region(Sichuan,China)were studied to assess their radical-scavenging ability on 1,1-diphenyl-2-picrylhydrazyl radicals and reducing power ability.Moreover,considering that anti-oxidants and free radical scavengers can also exert protective effect on endothelial cells from oxidative injury,these extracts were also evaluated for their anti-oxidative activity against cellular injury in the cultured human endothelial cell line(ECV304)induced by hydrogen peroxide(HO).Results All the extracts had radical-scavenging and/or reducing power ability,and the most active extract was found during flowering whereas the lowest appeared during vegetative growth period.The accumulation of anti-oxidative compounds was found to be affected by the altitude of growth environment.Total flavonoid content assay was also performed to support this outcome.Furthermore,these extracts also exhibited different effects on attenuating HO-induced cytotoxicity and inhibiting lipid peroxidation and LDH leakage from endothelial cells.Conclusion E.multiradiatus may be an important natural anti-oxidant and this property may contribute to verifying the utilization of this plant in Tibet folk medicine.
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Objective To search for chemical constituents with anti-oxidative activity from seeds of Jatropha curcas.Methods DPPH radical scavenging assay was used to screen fractions or constituents with anti-oxidative activities.Active fractions were separated by varied chromatography and then identified on the basis of physiochemical properties and spectroscopic methods.Results The n-butanol layer of ethanol extract from the seeds of J.curcas showed stronger activity than other fractions and was studied further.A new compound was isolated from this active layer, and its structure was identified as jatrophasin A (3,4,4',5'-tetrahydroxyl-3'-methoxyl-bisepoxylignan, 1).It showed stronger anti-oxidative activity compared with resveratrol.Conclusion Compound 1 is a new compound which has never been reported with strong anti-oxidative activity.
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Aim To study the protective effect of total extract of astragalus(TEA) on primary rat hepatocytes injured by CCl4 or H2O2 and its mechanism.Methods The primary hepatocytes were isolated by Ⅳ collaganase and injured by CCl4 or H2O2.The contents of malondialdehyde(MDA) and glutathion(GSH),glutathion peroxidase(GSHpx) activity of hepatocytes and the AST and /or ALT level in cultural supernatant were determined by general methods. Results (1) The elevation of MDA content of hepatocytes and AST level in supernatant of cultural hepatocytes,and the loss of GSH content and GSHpx activity induced by CCl4 were restored remarkably by TEA(5～80 mg?L-1);(2)The elevation of ALT level in the supernatant of hepatocytes and MDA content of hepatocytes, and the loss of GSH content and GSHpx activity induced by H2O2 were improved significantly by TEA(5～80 mg?L-1) treatment.Conclusion The results suggest that TEA possess direct protective action on primary hepatocyte in vitro injured by CCl4 or H2O2. These might be associated with its anti-oxidative activity.
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Objective To study the protective effect on CCl4-injured L-02 hepatocytes of polysaccharides from Hyriopsis cumingii(HCP) and try to explain the mechanism.Methods The L-02 hepatocytes were incubated and then injured by CCl4.The levels of AST,ALT,MDA and SOD in cultural supernatant were detected by general methods.Cell viability was assayed by MTT method.Results The polysaccharides(25,250 and 1000?g?L-1)could reduce the levels of AST,ALT,MDA in cultural supernatant which increased by CCl4.It also could boost the hepatocytes viability and elevate the level of SOD which reduced by CCl4.Conclusion The results suggest that polysaccharides from Hyriopsis cumingii have direct protective activity on hepatocytes injured in vitro.It might be associated with the anti-oxidative activity of polysaccharides from Hyriopsis cumingii.
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Objective To study the antioxidant activity of the extract from north Ph.praecox leaves.Methods The extract from north Ph.Praecox leaves was made by ultrasonic-assisted extraction process,and the concentration of the total flavonoids was detected by NaNO3-Al(NO3)3-NaOH methods.The antioxidant capacity of the extraction was detected by DPPH free radical scavenging method and CuSO4-Phen-Vc-H2O2-DNA reaction with ultra-weak chemiluminescence method.Results The bamboo leaf extract could scavenges the DPPH free radical with the IC50 value as 7.02 mg /L and could delay the development of the emission peak value(P