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1.
The aim of this study was to assess the chemical and biological profile of propolis samples collected in arid environments of north-western Argentina. The samples were from two phytogeographical regions (Prepuna and Monte de Catamarca Province). Propolis ethanolic extracts (PEE) and chloroform (CHL), hexane (HEX) and aqueous (AQ) sub-extracts of samples from three regions (CAT-I; CAT-II and CAT-III) were obtained. All PEE exhibited antioxidant activity in the DPPH radical scavenging assay (SC50 values between 28 and 43 microg DW/mL). The CHL extract was the most active (SC50 values between 10 and 37 microg DW/mL). The antioxidant activity in the beta-carotene bleaching assays was more effective for PEE and CHL (IC50 values between 2 and 9 microg DW/mL, respectively). A similar pattern was observed for antibacterial activity. The highest inhibitory effect on the growth of human Gram-positive bacteria was observed for CHL-III and CHL-I (Monte region) with minimal inhibitory concentration values (MIC100) of 50 to 100 microg DW/mL. Nine compounds were identified by HPLC-PAD. Two of them (2', 4'- dihydroxychalcone and 2',4'- dihydroxy 3'-methoxychalcone) were found only in propolis samples from the Monte phytogeographical region. We consider that the Argentine arid region is appropriate to place hives in order to obtain propolis of excellent quality because the dominant life forms in that environment are shrubby species that produce resinous exudates with a high content of chalcones, flavones and flavonols.  相似文献   

2.
Methanolic extracts of Chuquiraga straminea Sandwith, subfamily Barnadesioideae (Asteraceae) showed the presence of quercetin-3-O-glucoside, quercetin-3-O-rutinoside, kaempferol, kaempferol-3-O-glucoside and kaempferol-3-O-rutinoside. Antioxidant and antimicrobial activity was determined. The total extracts showed antioxidant activity by DPPH and ABTS method (SC50 14.5 to 34.9 microg/mL). A significantly positive correlation was observed between the antioxidant activity and the total phenolics (R2 > 0.93). The extracts were active against ten methicillin resistant and sensitive Staphylococcus aureus strains isolated from nosocomial infection (MIC values between 200 to 800 microg/mL). These preliminary studies are highly interesting as they open new ways for further applications in the treatment of infections by methicillin resistant S. aureus.  相似文献   

3.
The biological activities of propolis samples are the result of many bioactive compounds present in the propolis. The aim of the present study was to determine the various chemical compounds of some selected propolis samples collected from Palestine and Morocco by the High-Performance Liquid Chromatography–Photodiode Array Detection (HPLC-PDA) method, as well as the antioxidant and antibacterial activities of this bee product. The chemical analysis of propolis samples by HPLC-PDA shows the cinnamic acid content in the Palestinian sample is higher compared to that in Moroccan propolis. The results of antioxidant activity demonstrated an important free radical scavenging activity (2,2-Diphenyl-1-picrylhydrazyl (DPPH); 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and reducing power assays) with EC50 values ranging between 0.02 ± 0.001 and 0.14 ± 0.01 mg/mL. Additionally, all tested propolis samples possessed a moderate antibacterial activity against bacterial strains. Notably, Minimum Inhibitory Concentrations (MICs) values ranged from 0.31 to 2.50 mg/mL for Gram-negative bacterial strains and from 0.09 to 0.125 mg/mL for Gram-positive bacterial strains. The S2 sample from Morocco and the S4 sample from Palestine had the highest content of polyphenol level. Thus, the strong antioxidant and antibacterial properties were apparently due to the high total phenolic and flavone/flavonol contents in the samples. As a conclusion, the activities of propolis samples collected from both countries are similar, while the cinnamic acid in the Palestinian samples was more than that of the Moroccan samples.  相似文献   

4.
Hydnophytum formicarum Jack. (Rubiaceae) is a medicinal plant whose tubers possesses cardiovascular, anti-inflammatory and antiparasitic effects and have been used for the treatment of hepatitis, rheumatism and diarrhea. Herein we report the isolation of its active constituents and the testing of their antimicrobial activity against 27 strains of microorganisms using an agar dilution method and of their antioxidative activity using the DPPH and SOD assays. The results show that the crude hexane, dichloromethane, ethylacetate and methanol extracts exert such activities. Particularly, the crude ethyl acetate extract exhibits antigrowth activity against many Gram-positive and Gram-negative bacteria with MIC 256 microg/mL. Shewanella putrefaciens ATCC 8671 is completely inhibited at a lower MIC (128 microg/mL). Interestingly, Corynebacterium diphtheriae NCTC10356 is inhibited by all the tested extracts. Significantly, the ethyl acetate extract is also the most potent antioxidant, showing 83.31% radical scavenging activity with IC50 8.40 microg/mL in the DPPH assay. The other extracts display weak to moderate antioxidative activities, ranging from 28.60-56.80% radical scavenging. The SOD assay shows that methanol extract exhibits the highest activity (74.19% inhibition of superoxide radical). The dichloromethane and ethyl acetate extracts display comparable SOD activity. The promising bioactivities of the crude ethyl acetate extract guided the first isolation of bioactive flavonoid and phenolic compounds: isoliquiritigenin (2), protocatechualdehyde(3), butin (4) and butein (5) from this species. Their structures have been fully established by 1D and 2D NMR. In addition, stigmasterol was isolated from the crude hexane and dichloromethane extracts. The antimicrobial and cytotoxic activities of compounds 3-5 were evaluated. The tested compounds were inactive against HuCCA-1 and KB cell lines,showing ED50> 10 microg/mL. Protocatechualdehyde (3) completely inhibits the growth of Plesiomonas shigelloides with MIC 相似文献   

5.
The essential oil obtained by hydro-distillation from the flowers of Halimondendron halodendron (Leguminosae) was analyzed for its chemical composition by gas chromatography-mass spectrometry (GC-MS). Undecane (16.4%), dodecane (15.3%), tridecane (12.5%), decane (8.2%), 6,10,14-trimethyl-pentadecan-2-one (6.3%), methyl palmitate (6.0%), methyl linolenate (4.1%) and ethylcyclohexane (4.1%) were the major compounds of the thirty-five identified components of the oil. The essential oil was shown to have a broad spectrum of antimicrobial activity with MIC values ranging from 100 to 250 microg/mL, and IC50 values from 40.4 to 193.8 microg/mL. The oil also showed strong antioxidant activity, with an especially high metal chelating capacity of ferrous ions with an IC50 value of 7.4 microg/mL on ferrozine-Fe2+ complex formation.  相似文献   

6.
The chemical composition, and antioxidant and antimicrobial activities of the essential oil isolated from the leaf of Machilus japonica from Taiwan have been investigated. The essential oil from the fresh leaves was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of 97 compounds were identified, representing 100% of the oil. The main components identified were alpha-phellandrene (14.5%), alpha-pinene (12.8%), thymol (12.6%), beta-pinene (8.3%), alpha-terpineol (6.5%) and carvacrol (6.0%). The antioxidant activity of the oil was tested by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging capability test. The results showed that the IC50 was 51.8 microg/mL. The antimicrobial activity of the oil was tested by the disc diffusion and micro-broth dilution methods against ten microbial species. The oil exhibited strong growth suppression against Gram-positive bacteria and yeast, with inhibition zones of 48-54 mm and MIC values of 16.12-32.25 microg/mL, respectively. For the antioxidant and antimicrobial activities of the oil, the active source compounds were determined to be thymol and carvacrol.  相似文献   

7.
One new and eight known ceanothane- and lupane-type triterpenes were isolated from the root bark of Ziziphus cambodiana PIERRE (Rhamnaceae). Based on spectral analyses, the structure of the new compound was elucidated as 3-O-(4-hydroxy-3-methoxybenzoyl)ceanothic acid (3-O-vanillylceanothic acid) (1), while the known compounds were identified as lupeol (2), betulinaldehyde (3), betulinic acid (4), 2-O-E-p-coumaroyl alphitolic acid (5), alphitolic acid (6), zizyberanalic acid (7), zizyberenalic acid (8) and ceanothic acid (9). Compounds 1, 5 and 8 exhibited significant in vitro antiplasmodial activity against the parasite Plasmodium falciparum, with inhibitory concentration (IC50) values of 3.7, 0.9 and 3.0 microg/ml, respectively. Compounds 1 and 3-8 showed antimycobacterial activity against Mycobacterium tuberculosis with respective MIC values of 25, 25, 25, 12.5, 50, 50 and 100 microg/ml.  相似文献   

8.
The essential oil of the leaves Solanium spirale Roxb. was isolated by hydrodistillation and analyzed for the first time using GC and GC-MS. Thirty-nine constituents were identified, constituting 73.36% of the total chromatographical oil components. (E)-Phytol (48.10%), n-hexadecanoic acid (7.34%), beta-selinene (3.67%), alpha-selinene (2.74%), octadecanoic acid (2.12%) and hexahydrofarnesyl acetone (2.00%) were the major components of this oil. The antioxidant activity of the essential oil was evaluated by using the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assay. The oil exhibited week antioxidant activity with an IC50 of 41.89 mg/mL. The essential oil showed significant antibacterial activity against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus with MIC values of 43.0 microg/mL and 21.5 microg/mL, respectively. It also showed significant cytotoxicity against KB (oral cancer), MCF-7 (breast cancer) and NCI-H187 (small cell lung cancer) with the IC50 values of 26.42, 19.69, and 24.02 microg/mL, respectively.  相似文献   

9.
The volatile oil, obtained by hydro-distillation from Fusarium tricinctum, the endophytic fungus isolated from Paris polyphylla var. yunnanensis, was analyzed by gas chromatography-mass spectrometry (GC-MS). trans-1,2,3,3a,4,7a-Hexahydro-7a-methyl-5H-inden-5-one (73.1%), 2-methylene-4,8,8-trimethyl-4-vinyl bicyclo [5.2.0] nonane (12.0%), and 2,6-dimethyl-6-(4-methyl-3-pentenyl) bicyclo [3.1.1] hept-2-ene (4.5%) were the major compounds of the 15 identified components accounting for 95.4% of the volatile oil. The antimicrobial activity of the volatile oil was assayed against eight bacteria and two fungi. The minimum inhibitory concentration (MIC) values of the volatile oil against the test bacteria ranged from 25 to 45 microg/mL. The MIC values against the fungi Candida albicans and Magnaporthe oryzae were 100 and 225 microg/mL, respectively. The mean inhibitory concentration (IC50) values of the volatile oil against the test bacteria ranged from 17.8 to 31.6 microg/mL, and those of the volatile oil against C. albicans and M. oryzae were 84.3 and 204.3 microg/mL, respectively.  相似文献   

10.
Bioassay guided isolation of an antibacterial extract prepared from the fermentation broth of a Micromonospora sp. P1068 led to the isolation of eight compounds identified as (3R) 3,4',7-trihydroxy-isoflavanone (1), 3-hydroxydehydrodaidzein, daidzein (2), 3-methyl-1H-indole-2-carboxylic acid (3), 1H-indole-3-carboxaldehyde (4), 3-(p-hydroxyphenyl)-N-methylpropionamide, N-methylphloretamide (5), phenyl acetic acid (6), 2-hydroxy phenyl acetic acid (7) and 4-hydroxy-5-methoxy-benzoic acid (8). Compounds 1 and 5 were found to be novel chemical entities while 3 was isolated from a natural source for the first time. All compounds were evaluated for their antimicrobial activities against a panel of clinically significant microorganisms. Compound 4 was active against Staphylococcus aureus (MIC, 32 microg/ml), Enterococcus faecium (MIC, 32 microg/ml) and Escherichia coli (MIC, 64 microg/ml).  相似文献   

11.
Antioxidant compounds can be useful to prevent several degenerative diseases or as preservative in food and toiletries. Species of the Myrtaceae family are able to accumulate phenolic substances and those are closely related to the antioxidant activity due to their capacity to scavenge free radicals, protect against lipid peroxidation and quench reactive oxygen species. These facts prompted us to investigate the antioxidant capacity of the ethanolic extracts of the leaves of four Myrtaceae plants collected of the south of Brazil: Eugenia chlorophylla O. Berg., Eugenia pyriformis Cambess, Myrcia laruotteana Cambess and Myrcia obtecta (Berg) Kiacrsk. The antioxidant potential was performed using the DPPH (a single electron transfer reaction based assay) and ORAC (Oxygen Radical Absorbance Capacity, a hydrogen atom transfer reaction based assay) assays. Moreover, the total soluble phenolic content was also measured using the Folin-Ciocalteu reagent. A preliminary evaluation of the ethanolic extracts of these Myrtaceae plants revealed high levels of phenolic compounds (343.7-429.3 mg GAE) as well as high antioxidant activity according to both methods (1338 a 3785 micromol of TE/g of extract in ORAC and SC50 in the range of 1.70 and 33.7 microg/mL in the DPPH). The highest antioxidant activity obtained by DPPH assay was exhibited by ethanol extract of the leaves of E. pyriformis (1.70 microg/mL), followed by extracts of M. laruotteana (3.38 microg/mL) and M. obtecta (6.66 microg/mL). In comparison with controls, in the DPPH assay, the extract of E. pyriformis was more active than trolox (SC50 = 2.55 microg/mL), while the extracts of M. laruotteana and M. obtecta were more actives than quercetin (SC50 = 7.80 microg/mL). In the ORAC assay, all species also show good antioxidant capacity (>1000 micromol of TE/g). Initial HPLC-UV/DAD and ESI-MS confirmed the presence of phenolic acids constituents in the ethanol extracts. The results indicate the presence of compounds possessing promising antioxidant/free-radical scavenging activity in the analyzed extracts of Myrcia and Eugenia plants of the south of Brazil.  相似文献   

12.
The essential oil from the leaves of Annona vepretorun was obtained by hydrodistillation using a Clevenger-type apparatus and analyzed by GC-MS and GC-FID. Eighteen compounds representing 98.1% of the crude essential oil were identified. The major compounds identified were bicyclogermacrene (43.7%), spathulenol (11.4%), alpha-felandrene (10.0%), alpha-pinene (7.1%), (E)-beta-ocimene (6.8%), germacrene D (5.8%), and p-cymene (4.2%). The trypanocidal activity against Trypanosoma cruzi epimastigote forms, as well as, the antimicrobial and antioxidant proprieties was investigated. The essential oil showed a potent trypanocidal activity with IC50 value of 31.9 +/-1.3 microg x mL(-1). For antimicrobial activity, the best result was observed against Candida tropicalis with a MIC value of 100 microg x mL(-1). For antioxidant capacity the essential oil showed weak activity.  相似文献   

13.
This study investigated the chemical composition, antioxidant, antimicrobial and anti-wood-decay fungal activities of the essential oil isolated from the twigs of Taiwania cryptomerioides from Taiwan. The essential oil was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of 35 compounds were identified, representing 100% of the oil. The main components identified were alpha-cadinol (45.9%), ferruginol (18.9%) and beta-eudesmol (10.8%). The antioxidant activity of the oil was tested by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging capability test. The results showed an IC50 of 90.8 +/- 0.2 microg/mL. The active source compound was ferruginol. The antimicrobial activity of the oil was tested by the disc diffusion and micro-broth dilution methods against ten microbial species. The oil exhibited strong growth suppression against Gram-positive bacteria and yeast with inhibition zones of 45-52 mm and MIC values of 31.25-62.5 microg/mL, respectively. The anti-wood-decay fungal activity of the oil was also evaluated. The oil demonstrated excellent activity against four wood-decay-fungal species. For the antimicrobial and anti-wood-decay fungal activities of the oil, the active source compounds were determined to be alpha-cadinol, beta-eudesmol and ferruginol.  相似文献   

14.
The crude extracts and isolated compounds of Piper porphyrophyllum (Piperaceae) were evaluated for antibacterial and anti-inflammatory activities. The ethyl acetate extract and 3′,4′,5,7-tetramethoxyflavone exhibited the highest activity against Staphylococcus aureus giving values of MIC = 62.5 and 250 μg/mL, respectively. 5-Hydroxy-7-methoxyflavanone and 4′,5-dihydroxy-3′,7-dimethoxyflavone were active against Pseudomonas aeruginosa, both with MIC value 125 μg/mL. The hexane extract and 4′,5-dihydroxy-3′,7-dimethoxyflavone gave the highest anti-inflammatory activity in in vitro quantitative lipoxygenase inhibition assay with inhibitory activity of (IE) 99.72% and 91.81%, respectively.  相似文献   

15.
Two new C-3/C-3' biflavanones, chamaejasmenin D (1) and isochamaejasmenin B (2), were isolated from the roots of Stellera chamaejasme, together with five known biflavanones, chamaejasmenin A (3), chamaejasmenin B (4), neochamaejasmin A (5), sikokianin A (6), and chamaejasmenin C (7). Their structures were elucidated by spectroscopic methods, including 2D NMR techniques. Among these compounds, 1-3 demonstrated potent antimitotic and antifungal activity with minimum inhibitory concentration (MIC) values of 6.25, 6.25, and 3.12 microg/ml, respectively.  相似文献   

16.
Isoferulic acid (3-hydroxy-4-methoxycinnamic acid, IFA), the isomer of ferulic acid (4-hydroxy-3-methoxycinnamic acid), is a rare phenolic acid occurring in Rhizoma Cimicifugae. Unlike ferulic acid, which has been well investigated, the antioxidant activity of IFA has not been measured. In this study, IFA was systematically evaluated for its in vitro antioxidant activity for the first time. IC50 values were calculated of 7.30 +/- 0.57, 4.58 +/- 0.17, 1.08 +/- 0.01, 8.84 +/- 0.43, 7.69 +/- 0.39, 1.57 +/- 0.2, 13.33 +/- 0.49 microg/mL, respectively, for lipid peroxidation, DPPH (1,1-diphenyl-2-picrylhydrazyl radical) and ABTS (3-ethylbenzthiazoline-6-sulfonic acid diammonium salt) radical scavenging, reducing power on Fe3+ and CU2+ ions, and hydroxyl and superoxide anion radical scavenging. Comparison with the IC50 values with those of the positive controls, Trolox and butylated hydroxyanisole (BHA), it can be concluded that isoferulic acid is an effective natural antioxidant in both lipid and aqueous media.  相似文献   

17.
The antioxidant activity of the crude extract and solvent fractions obtained from the leaves of Bauhinia galpinii was evaluated in terms of capacity to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals. The crude extract and the more polar solvent fractions (ethyl acetate and butanol) showed considerable antioxidant activity. The antioxidant potential of the extracts, expressed as EC50, ranged between 28.85 +/- 1.28 microg mL(-1)and 118.16 +/- 6.41 microg mL(-1). L-Ascorbic acid was used as a standard (EC50 = 19.79 +/- 0.14 microM). Bioassay guided fractionation of the two active solvent fractions led to the isolation of three flavonoid glycosides, identified as: quercetin-3-O-galactopyranoside (1), myricetin-3-O-galactopyranoside (2), and 2'-O-rhamnosylvitexin (3). These compounds are reported for the first time from this species. The structures of the compounds were determined on the basis of spectral studies (1H NMR, 13C NMR and MS). Their antioxidant potential was evaluated using a DPPH spectrophotometric assay. Compound 2 had higher and 3 had lower antioxidant activity than L-ascorbic acid. No cytotoxic effects were displayed by compounds 1 and 3, but compound 2 was cytotoxic to Vero cells (LC50 = 74.68 microg mL(-1)) and bovine dermis cells (LC50 = 30.69 microg mL(-1)).  相似文献   

18.
Crop diseases caused by Fusarium pathogens, among other microorganisms, threaten crop production in both commercial and smallholder farming. There are increasing concerns about the use of conventional synthetic fungicides due to fungal resistance and the associated negative effects of these chemicals on human health, livestock and the environment. This leads to the search for alternative fungicides from nature, especially from plants. The objectives of this study were to characterize isolated compounds from Combretum erythrophyllum (Burch.) Sond. and Withania somnifera (L.) Dunal leaf extracts, evaluate their antifungal activity against Fusarium pathogens, their phytotoxicity on maize seed germination and their cytotoxicity effect on Raw 264.7 macrophage cells. The investigation led to the isolation of antifungal compounds characterized as 5-hydroxy-7,4′-dimethoxyflavone, maslinic acid (21-hydroxy-3-oxo-olean-12-en-28-oic acid) and withaferin A (4β,27-dihydroxy-1-oxo-5β,6β-epoxywitha-2-24-dienolide). The structural elucidation of the isolated compounds was established using nuclear magnetic resonance (NMR) spectroscopy, mass spectroscopy (MS) and, in comparison, with the available published data. These compounds showed good antifungal activity with minimum inhibitory concentrations (MIC) less than 1.0 mg/mL against one or more of the tested Fusarium pathogens (F. oxysporum, F. verticilloides, F. subglutinans, F. proliferatum, F. solani, F. graminearum, F. chlamydosporum and F. semitectum). The findings from this study indicate that medicinal plants are a good source of natural antifungals. Furthermore, the isolated antifungal compounds did not show any phytotoxic effects on maize seed germination. The toxicity of the compounds A (5-hydroxy-7,4′-dimethoxyflavone) and AI (4β,27-dihydroxy-1-oxo-5β,6β-epoxywitha-2-24-dienolide) was dose-dependent, while compound B (21-hydroxy-3-oxo-olean-12-en-28-oic acid) showed no toxicity effect against Raw 264.7 macrophage cells.  相似文献   

19.
A new neolignan, 3,4-dimethoxy-3',4'-methylenedioxy-2,9-epoxy-6,7-cyclo-1,8-neolign-11-en-5(5H)-one, which has been named (+)-kunstlerone (1), together with six known alkaloids: (+)-norboldine (2), (+)-N-methylisococlaurine (3), (+)-cassythicine (4), (+)-laurotetanine (5), (+)-boldine (6) and (-)-pallidine (7), were isolated from the leaves of Beilschmiedia kunstleri. The structures were established through various spectroscopic methods notably 1D- and 2D-NMR, UV, IR and LCMS-IT-TOF. (+)- Kunstlerone (1) showed a strong antioxidant activity, with an SC(50) of 20.0 μg/mL.  相似文献   

20.
Bioassay-guided fractionation of the chloroform extract of bulbs of the orchid P. michuacana was used to determine the chemical identity of bioactive constituents. The use of DPPH assay led to the isolation of two new lanostane triterpenoids 3a-acetoxy, 24-hydroxy-24-methyl-5a-lanosta-9(11),25-diene (1) and 3a-acetoxy, 24-hydroxy-24-methyl-5a-lanosta-9(11)ene (2), a new stilbene a-a'-dihydro,3',5',2-trimethoxy-3-hydroxy4-acetyl-4'-isopentenylstilbene (3), the phenanthrene 4,6,7-trihydroxy-2-methoxy-8-(methylbut-2enyl)phenanthrene-1,1'-4',6',7'-trihydroxy-2'-methoxy-8'-(methylbut-2'-enyl)phenanthrene (4), one new abietane-type diterpene 12-hydroxy-3{,7{,18a-triacetoxy-8,11,13-abietatriene (5), together with gigantol (6), a known compound. The compounds were identified by spectral analysis and comparison with spectroscopic data reported in the literature. Compounds 3, 4, 5, and 6 showed DPPH and ABTS radical-scavenging and anti-lipid peroxidation activities, but none of the isolated triterpenes showed promising antioxidant activity.  相似文献   

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