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1.
Fruits, vegetables and medicinal herbs rich in phenolics antioxidants contribute toward reduced risk of age-related diseases and cancer. In this study, Psidium guajava leaf extract was fractionated in various organic solvents viz. petroleum ether, benzene, ethyl acetate, ethanl and methanol and tested for their antioxidant and antimutagenic properties. Methanolic fraction showed maximum antioxidant activity comparable to ascorbic acid and butylated hydroxyl toluene (BHT) as tested by DPPH free radical scavenging, phosphomolybdenum, FRAP (Fe3?+?reducing power) and CUPRAC (cupric ions (Cu2+) reducing ability) assays. The fraction was analyzed for antimutagenic activities against sodium azide (NaN3), methylmethane sulfonate (MMS), 2-aminofluorene (2AF) and benzo(a)pyrene (BP) in Ames Salmonella tester strains. The methanol extracted fraction at 80?μg/ml concentration inhibited above 70% mutagenicity. Further, phytochemical analysis of methanol fraction that was found to be most active revealed the presence of nine major compounds by gas chromatography–mass spectrometry (GC–MS). This data suggests that guava contains high amount of phenolics responsible for broad-spectrum antimutagenic and antioxidant properties in vitro and could be potential candidates to be explored as modern phytomedicine.  相似文献   

2.
Spices and herbs are recognized as sources of natural antioxidants and thus play an important role in the chemoprevention of diseases and aging. Piper cubeba is one among them and known for its medicinal properties for decades. Various biological activities are associated with its extract and phytocompounds. However, the anti-mutagenic activity of antioxidant rich extract is less explored. In this study, we performed the fraction-based antioxidant activity of P. cubeba using four different assays and evaluated the anti-mutagenic activity of most potent antioxidant fraction using Salmonella typhimurium tester strains against four mutagens (methyl methanesulfonate [MMS], sodium azide [SA], benzo(a)pyrene, and 2-aminoflourene) respectively. Among all tested fractions at 25–200?µg/ml, ethanolic extract revealed highest antioxidant activity and significant anti-mutagenicity against both direct and indirect acting mutagens at least one tester strain. Phytochemical analysis by gas chromatography–mass spectrometry (GC/MS) revealed the presence of various phytocompounds including copaene, isocaryophyllene, α-cubebene, etc. Molecular docking studies on DNA binding interactions of GC/MS detected phytocompounds highlight the possible mode of binding. In summary, these in vitro studies have provided the scientific basis for validation of using this plant in the traditional system of medicine and highlighted the need for exploring the role of various compounds for therapeutic efficacy. On the other hand, synergistic interaction among phytocompounds is to be explored to optimize or standardize the extracts for the exploitation in modern phytomedicine.  相似文献   

3.
As part of our ongoing studies on the synthesis of bioactive coumarin compounds, we synthesized a series of new coumarin-fused 1,4-thiazepines using a simple method. The biological activity of target compounds along with 3-(2-hydroxybenzylidene)chroman-2,4-dione intermediates was screened by evaluation of their antioxidant and cytotoxic activities. The antioxidant activity was assessed using two methods, namely, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method and ferric reducing antioxidant power (FRAP) assay. 4-Methoxyphenolic compound 5d in thiazepine series showed the most potent scavenging activity, while the 4-bromophenolic derivative 5b was the most efficient compound in FRAP assay. Also, the result of cytotoxic evaluation using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay demonstrated that compound 5b is at least twofold more potent than etoposide against MCF-7, SK-N-MC, and MDA-MB 231 cell lines.  相似文献   

4.
Phytochemical investigation of the extract of Arctii Fructus led to the isolation and characterization of two new compounds, named arctiisesquineolignan B (1) and arctiiphenolglycoside A (2). Their structures were elucidated by means of spectroscopic methods (UV, IR, HR-ESI-MS, 1D and 2D NMR) and chemical evidence, as well as by comparison with known analogs in the literature. Compound 2 exhibited stronger antioxidant activity than the positive control ascorbic acid at a concentration of 10 μM.  相似文献   

5.
Hypericum orientale L. (Hypericaceae), Helichrysum plicatum Dc. subsp. plicatum (Asteraceae), Centaurea drabifolia Sm. subsp. drabifolia (Asteraceae), Centaurea drabifolia Sm. subsp. detonsa (Bornm.) Wagenitz (Asteraceae), Achillea wilhelmsii C. Koch (Asteraceae), and Rubus canescens Dc. var. canescens (Rosaceae) are used for the treatment of hemorrhoids, abdominal pains, and wound healing in traditional Turkish medicine. In order to assess these uses, methanol extracts prepared from their aerial parts were investigated for antioxidant, anti-inflammatory, and antinociceptive activities. All extracts demonstrated scavenging properties against superoxide anion (O2?–) and hydrogen peroxide (H2O2) in a non-cellular system, and toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. They also inhibited Cu2+-induced low-density lipoprotein (LDL) peroxidation. Among the tested plants, R. canescens var. canescens, H. orientale, and H. plicatum subsp. plicatum were the most effective on ROS in a non-cellular system. Another goal in this work was to test in vivo anti-inflammatory and antinociceptive activities of some of these plants not previously studied. The methanol extracts of C. drabifolia subsp. drabifolia, H. orientale, and C. drabifolia subsp. detonsa were shown to possess significant inhibitory activity in mice against carrageenan-induced hind paw edema and in p-benzoquinone-induced writhings.  相似文献   

6.
In this study, the antioxidant and antiacetylcholinesterase activities of Sorbus torminalis (L.) Crantz fruits were evaluated. Total phenolic and flavonoid compounds, 2,2′-azino-bis (3-ethylbenzothioazoline-6-sulfonic acid), 2,2′-diphenyl-1-picrylhydrazyl, and superoxide anion radicals scavenging activities and ferric-reducing antioxidant power of water, ethyl acetate, acetone, and methanol extracts were determined for the measurement of the antioxidant activity. Quercetin and α-tocopherol were used as standard antioxidants. The inhibitory effect of the water extract on acetylcholinesterase (AChE) was evaluated using the Ellman method and galantamine was used as a standard. Water extract had the highest total phenolic concentration and the strongest antioxidant activity followed by ethyl acetate and acetone extracts whereas methanol extract has the lowest phenolics and weakest antioxidant activity. Moreover, water extract showed moderate ability to inhibit AChE. It was concluded that fruits of S. torminalis have antioxidant and anti-AChE activities and that the plant might be a natural source of antioxidants and AChE inhibitors.  相似文献   

7.
壳寡糖的抗氧化及肝保护功能   总被引:3,自引:0,他引:3  
目的研究壳寡糖(COS)的抗氧化能力和对CCl4诱导的小鼠肝损伤的保护作用,并初步探讨其作用机制。方法雄性昆明种小鼠,腹腔注射CCl4(20 mg.kg-1)制造肝损伤模型,实验组提前连续12 d灌胃给予COS(1.5 g.kg-1)。小鼠经CCl4损伤24 h后,取血,分离得到血清,测定各组小鼠血清中丙氨酸转氨酶(ALT)和天门冬氨酸转氨酶(AST)的活性。脱颈处死小鼠,取部分肝组织,分别测定肝匀浆中总抗氧化能力(T-AOC)、总巯基(T-SH)和非蛋白结合巯基(NP-SH)含量、金属硫蛋白含量(MT)、丙二醛(MDA)含量和DNA损伤情况等指标。结果COS组与CCl4组相比,ALT、AST活性和MDA含量分别下降了62.2%、52.9%和34.3%。T-AOC和NP-SH含量分别提高了26.1%和16.3%。MT含量是空白对照组的2.15倍。但是没有抑制T-SH含量降低的作用。DNA电泳结果显示,COS组与CCl4组的DNA链都形成一系列1 kb大小左右的DNA片断。结论COS具有抗氧化能力,对CCl4诱导的小鼠肝损伤有较为明显的保护作用,但是不能减轻DNA的氧化性损伤。  相似文献   

8.
《Pharmaceutical biology》2013,51(10):1014-1022
Context: Several Juniperus species (Cupressaceae) are utilized in folk medicine in the treatment of infections and skin diseases.

Objective: This work was designed to evaluate the antioxidant and antimicrobial potential of methanol and water branches extracts of Juniperus species from Turkey: Juniperus communis L. var. communis (Jcc), Juniperus communis L. var. saxatilis Pall. (Jcs), Juniperus drupacea Labill. (Jd), Juniperus oxycedrus L. subsp. oxycedrus (Joo), Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. (Jom).

Materials and methods: Total phenolics, total flavonoids and condensed tannins were spectrophotometrically determined. The antioxidant properties were examined using different in vitro systems. The toxicity was assayed by Artemia salina lethality test. The antimicrobial potential against bacteria and yeasts was evaluated using minimum inhibitory concentration and minimum bactericidal concentration (MIC/MBC) measurements. The effect on bacteria biofilms was tested by microtiter plate assay.

Results: Both in the DPPH (1,1-diphenyl-2-picrylhydrazyl) and TBA (thiobarbituric acid) test Jom resulted the most active (IC50?=?0.034?±?0.002?mg/mL and 0.287?±?0.166 µg/mL). Joo exhibited the highest reducing power (1.78?±?0.04 ASE/mL) and Fe2+ chelating activity (IC50?=?0.537?±?0.006?mg/mL). A positive correlation between primary antioxidant activity and phenolic content was found. The extracts were potentially non-toxic against Artemia salina. They showed the best antimicrobial (MIC?=?4.88-30.10 µg/mL) and anti-biofilm activity (60–84%) against S. aureus.

Discussion and conclusion: The results give a scientific basis to the traditional utilization of these Juniperus species, also demonstrating their potential as sources of natural antioxidant and antimicrobial compounds.  相似文献   

9.
Derris eriocarpa How is an important medicinal plant, which is used as Zhuang ethnomedicine and Dai ethnomedicine to treat various diseases. One new compound, 3′,4′-di-O-methylene-5-hydroxy-7-methoxy-6-isopentenyl isoflavone (1) and a known synthetic but new naturally occurring compound trans-3,4,5-trimethoxy-4′-isopentenyloxyl-stilbene (2), together with five known compounds, 5,7-dimethoxy-6-(3-methyl-2-butenyl)-4′-hydroxyl isoflavones (3), robustone (4), trans-3,4,5,4′-tetramethoxy-stilbene (5), robustic acid (6), and robustin (7) were isolated from the stem of D. eriocarpa. Spectroscopic analysis revealed the chemical structures of compounds 17.. Compounds 1 and 3 exhibited significant scavenging activities against 1,1-diphenyl-2-picrylhydrazyl radical and superoxide anions. Compounds 13 exhibited potent antiproliferative activity on Hela cells.  相似文献   

10.
Context: The pollen of Typha angustifolia L. (Typhaceae) has been used as a traditional Chinese medicine for improving the microcirculation and promoting wound healing. Flavonoids are the main constituent in the plant, but little is known about the antioxidant activity of the principal constituent of the pollen in detail.

Objectives: To assess the antioxidant activities of ethanol and water extracts and two constituents of the pollen.

Materials and methods: Plant material (1?g) was extracted by 95% ethanol and water (10?mL?×?2, 1?h each), respectively. The extracted activities (0.8–2.6?mg/mL) were measured by DPPH and the reducing activity of ferric chloride (1.7–2.6?mg/mL). Typhaneoside and isorhamnetin-3-O-neohesperidoside (I3ON) (2.8–70?μmol/L) were investigated on the relationship between NO, MDA and SOD in HUVECs treated with 100?μg/mL of LPS for 24?h.

Results: Nine compounds were identified by UPLC-MS. Ethanol extract showed IC50 values in DPPH (39.51?±?0.72) and Fe3+ reducing activity (82.76?±?13.38), higher than the water extract (50.85?±?0.74) and (106.33?±?6.35), respectively. Typhaneoside and I3ON promoted cell proliferation at the respective concentration range of 2.8 to 70?μmol/L (p?p?p?p?Conclusions: The constituents from Typha angustifolia could be a novel therapeutic strategy for LPS-induced inflammation.  相似文献   

11.
The antioxidant properties of different almond cultivars (cv.), either regional (Casanova, Duro Italiano, Molar, Orelha de Mula and Pegarinhos cv.) or commercial (Ferraduel, Ferranhês, Ferrastar and Guara cv.) were evaluated through several chemical and biochemical assays: DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, reducing power, inhibition of β-carotene bleaching, inhibition of oxidative hemolysis in erythrocytes, induced by 2,2′-azobis(2-amidinopropane)dihydrochloride (AAPH), and inhibition of thiobarbituric acid reactive substances (TBARS) formation in brain cells, all used as models for the lipid peroxidation damage in biomembranes. The EC50 values were calculated for all the methods in order to evaluate the antioxidant efficiency of each almond cultivar. Bioactive compounds such as phenols and flavonoids were also obtained and correlated to antioxidant activity. The results obtained were quite heterogeneous, revealing significant differences among the cultivars assayed. Duro Italiano cv. revealed better antioxidant properties, presenting lower EC50 values in all assays, and the highest antioxidants contents. The protective effect of this cultivar on erythrocyte biomembrane hemolysis was maintained during 4 h.  相似文献   

12.
目的:合成长春西汀-维生素C缀合物,并考察其生物活性。方法:以长春西汀和维生素C为起始原料,经4步反应制得目标产物长春西汀-维生素C缀合物,并采用DPPH·自由基法测定其体外抗氧化活性。结果与结论:目标产物总产率为15.8%,其结构经IR、^1HNMR、^13CNMR和MS确证。初步体外抗氧化活性研究表明,该化合物具有一定的体外抗氧化活性。  相似文献   

13.
Abstract

Five flavonoids, including 3,7,4′-trimethoxy-5-hydroxyflavone (1), 3,4′-dimethoxy-5,7-dihydroxyflavone (2), 5,7,4′-trimethoxy-3-hydroxyflavone (3), 3,5,7,4′-tetramethoxyflavone (4), and 7,4′-dimethoxy-3,5-dihydroxyflavone (5), were isolated from the rhizome of Hedychium thyrsiforme and assayed for antioxidant and antitumor promoting activities. The antioxidant assays showed that 5,7,4′-trimethoxy-3-hydroxyflavone, 7,4′-dimethoxy-3,5-dihydroxyflavone and 3,4′-dimethoxy-5,7-dihydroxyflavone had strong activities. Only two compounds, 5,7,4′-trimethoxy-3-hychoxyflavone and 7,4′-dimethoxy-3,5-dihydroxyflavone, were found to be strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavengers with fifty percent inhibition concentration (IC50) values of 92 and 119 μM, respectively. Antitumor promoting assays indicated that all the flavonoids showed strong inhibition activity towards Epstein-Barr virus (EBV) activation in Raji cells.  相似文献   

14.
Phenolic compounds of dark and clear honeys from Trás-os-Montes of Portugal were extracted with Amberlite XAD-2 and evaluated for their antioxidant and antimicrobial activities. The antioxidant effect was studied using the in vitro test capacity of scavenge the 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical and of reducing power of iron (III)/ferricyanide complex. The antimicrobial activity was screened using three Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus, Staphylococcus lentus) and three Gram-negative bacteria (Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli). The results obtained from the partial identification of honey phenolic compounds by high-performance liquid chromatography with a diode array detector showed that p-hydroxibenzoic acid, cinnamic acid, naringenin, pinocembrin and chrysin are the phenolic compounds present in most of the samples analyzed. Antioxidant potential was dependent of honey extract concentration and the results showed that dark honey phenolic compounds had higher activity than the obtained from clear honey. In the biological assays, results showed that S. aureus were the most sensitive microrganisms and B. subtilis, S. lentus, K. pneumoniae and E. coli were each moderately sensitive to the antimicrobial activity of honey extracts. Nevertheless, no antimicrobial activity was observed in the test with P. aeruginosa.  相似文献   

15.
The antioxidant and antibacterial activities of phenolic compounds from cultivated and wild Tunisian Ruta chalepensis L. leaves, stems, and flowers were assessed. The leaves and the flowers exhibited high but similar total polyphenol, flavonoid, and tannin content. Moreover, two organs showed strong, although not significantly different, total antioxidant activity, 2,2-diphenyl-1-picrylhydrazyl scavenging ability, and reducing power. Investigation of the phenolic composition showed that vanillic acid and coumarin were the major compounds in the two organs, with higher percentages in the cultivated organs than in the spontaneous organs. Furthermore, R. chalepensis extracts showed marked antibacterial properties against human pathogen strains, and the activity was organ- and origin-dependent. Spontaneous stems had the strongest activity against Pseudomonas aeruginosa. From these results, it was concluded that domestication of Ruta did not significantly affect its chemical composition and consequently the possibility of using R. chalpensis organs as a potential source of natural antioxidants and as an antimicrobial agent in the food industry.  相似文献   

16.
Abstract

An aqueous extract of Limoniastrum guyonianum gall (G extract) was tested on Salmonella typhimurium to assess its mutagenic and antimutagenic effects. This extract showed no mutagenicity when tested with S. typhimurium strain TA104 either with or without exogenous metabolic activation mixture (S9), whereas our findings revealed that the aqueous gall extract induced a mutagenic effect in S. typhimurium TA1538 when tested in the presence, as well as in the absence, of S9 activation mixture at the concentration of 500?µg/mL. Thus, the same concentration produced a mutagenic effect, when incubated with S. typhimurium TA100 in the presence of metabolic activation mixture. In contrast, our results showed a weak antimutagenic potential of the same extract against sodium azide in the presence of S. typhimurium TA100 and S. typhimurium TA1538 without metabolic activation (S9), whereas, in the presence of S. typhimurium TA104, we obtained a significant inhibition percentage (76.39%) toward 3.25?µg/plate of methylmethanesulfonate. Antimutagenicity against aflatoxin B1, 4-nitro-o-phenylene-diamine and 2-aminoanthracène was significant, with an inhibition percentage of, respectively, 70.63, 99.3 and 63.37% in the presence of, respectively, S. typhimurium TA100, S. typhimurium TA1538 and S. typhimurium TA104 strains at a concentration of 250?µg/plate after metabolic activation (S9). Antioxidant capacity of the tested extract was evaluated using the enzymatic (xanthine/xanthine oxidase assay) and the nonenzymatic (2,2-diphenyl-1-picrylhydrazyl) system. G extract exhibited high antioxidant activity.  相似文献   

17.
Activity cliffs are formed by structurally similar compounds having large potency differences. Their study is a focal point of SAR analysis. We present a first systematic survey of single- and multitarget activity cliffs contained in currently available bioactive compounds. Approximately 12% of all active compounds were involved in the formation of activity cliffs. Perhaps unexpectedly, activity cliffs were found to be similarly distributed over different protein target families. Moreover, only approximately 5% of all activity cliffs were multitarget cliffs. Importantly, we also found that only very few multitarget cliffs were formed by compounds having different target selectivity. In addition, 'polypharmacological cliffs', i.e., multitarget activity cliffs involving targets from different protein families, were also only rarely found. Taken together, our findings reveal that only approximately 2% of all pairs of structurally similar compounds sharing the same biological activity form activity cliffs but that, on average, approximately one of 10 active compounds is involved in the formation of one or two single-target cliffs of large magnitude (with at least 100-fold difference in potency). These compounds provide a rich source of SAR information and can be identified across many different target families.  相似文献   

18.
Reactive oxygen species are implicated in various inflammatory disorders. Vitex negundo is mentioned in Ayurveda as useful in treating arthritic disorders. The present work was undertaken to evaluate the antioxidant potential and anti-inflammatory activity of the plant. The total methanol extract of the plant was standardized in terms of total polyphenols. The standardized extract in a dose of 100 mg/kg caused a comparable reduction in edema with that of diclofenac sodium (25 mg/kg) when evaluated for antiinflammatory activity by carrageenan-induced rat paw edema method. The extract also exhibited a strong free radical scavenging activity by 1,1-diphenyl-2-picrylhydrazyl method and caused a significant reduction in the formation of thiobarbituric acid reacting substances when evaluated for its lipid peroxidation inhibitory activity. The results strongly suggest that radical quenching may be one of the mechanisms responsible for its antiinflammatory activity.  相似文献   

19.
The present work discusses the establishment of a green route for the rapid synthesis of silver nanoparticles (AgNPs) using an alcoholic extract of Reinwardtia indica (AERI) leaves which act as a reducing as well as a capping agent. The change in color from yellowish green to dark brown confirmed the synthesis of AgNPs. A characteristic surface plasmon resonance (SPR) band at 436?nm advocated the presence of AgNPs. The synthesis process was optimized using one factor at a time approach where 1.0?mM AgNO3 concentration, 5?mL 0.4% (v/v) of AER inoculum dose and 30?min of sunlight exposure were found to be the optimum conditions. The synthesized AgNPs was characterized by several characterizing techniques such as HR- TEM, SAED, HR-SEM, EDX, XRD, FTIR and AFM analysis. For evaluation and comparison of AgNPs with AERI used human pathogen E. coli, P. aeurogenosa, S. aeurus and C. albicans for antimicrobial, for cytotoxicity study SiHa cell line at concentration of (10, 50, 100, 250 and 500?µg mL?1) and for enzymatic assay superoxide dismutase, catalase, malondialdehyde and glutathione peroxidase method were used. The size of nanoparticle in the range of 3–15?nm was confirmed TEM, spherical shape by SEM and crystal lattice nature by XRD. AFM results revealed the 2?D and 3?D pattern of particle scatter nature on the surface. This protocol as simple, rapid, one step, eco-friendly, nontoxic and AgNPs showed strong antimicrobial activity as well as cytotoxic potential in comparison to AERI.  相似文献   

20.
Ziziphus jujuba (Z. jujube) is a herb used traditionally for the treatment of different aliment since ancient times, however, the scientific information on this plant is still insufficient. The pure active chemical compounds and crude extracts of Z. jujube can be used in food, formulated pharmaceutical products, natural antioxidant, antibiotics, anticancer agent and preservatives. Therefore, the objective of this work is to determine the cytotoxic and antimicrobial activities of different polarity of crude fractions of locally grown Z. jujube by applying brine shrimp lethality and agar gel disc diffusion bioassay. The cytotoxic result reveals that all prepared crude fractions from the leaves and fruits were lethal to all shrimp larvae at a concentration of 1000 μg/ml. Among the leaves crude fractions, butanol extract showed the highest cytotoxic activity with LC50 value of 8.69 μg/ml, whereas the lowest activity was in chloroform crude extract with LC50 value of 45.12 μg/ml. Similarly, in fruits, the highest activity was in ethyl acetate extract with an LC50 value of 11.62 μg/ml and the lowest was in water extract with an LC50 value of 149.28 μg/ml. The methanol and its corresponding fractions were displayed moderate antimicrobial activity against Gram (+ and ?) bacteria at various concentrations with a zone of inhibition range of 0–17 mm. Therefore, the active polar crude fraction of Z. jujuba or its pure component could be candidates for use as safe, effective and comparatively cheap antibiotics and anticancer agents.  相似文献   

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