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1.
Ursolic acid (UA) and oleanolic acid (OA) are triterpenoid compounds found in food, medicinal herbs and various other plants in free form or bound to glycosides. Both substances are known for their antimicrobial, hepatoprotective, anti-inflammatory, antiallergic, antiviral and cytotoxic activities. In the present study, we evaluated the antimutagenic potential of UA and OA using the micronucleus test in peripheral blood and bone marrow of Balb/c mice. The animals were divided into 10 treatment groups: mice treated with UA (80 mg/kg b.w.); OA (80 mg/kg b.w.); a mixture of UA and OA (80 mg/kg b.w.); the antineoplastic agent doxorubicin (DXR, 90 mg/kg b.w.); DMSO and DXR; UA and DXR; OA and DXR; UA, OA and DXR, and negative and solvent controls. UA, OA and a mixture of UA and OA were administered to the animals by gavage, followed by the intraperitoneal injection of DXR. The results showed a significant reduction in micronucleus frequency in the groups concomitantly treated with the triterpenoid compounds and DXR compared to that treated with DXR alone. The present results demonstrate the antimutagenic activity of UA and OA under the experimental conditions used in this study.  相似文献   

2.
Protective effects of ursolic acid and oleanolic acid in leukemic cells   总被引:5,自引:0,他引:5  
Ursolic acid (UA) and oleanolic acid (OA) have similar chemical structures but differ in the position of one methyl group on the ring E. We investigated protective effects of these two triterpenoic acids against H2O2-induced DNA damage in leukemic L1210, K562 and HL-60 cells using single-cell gel electrophoresis (SCGE). We compared their protective effects (antioxidant activities) with respect to the different position of the methyl group in their chemical structures. After 24 h pre-treatment of cells both compounds investigated inhibited significantly the incidence of DNA single strand breaks induced by H2O2. The concentration range of UA and OA was in all experiments 2.5–10 μmol/l. The antioxidant activity of OA determined by SCGE was significantly higher compared to UA in L1210 (+P < 0.05) and K562 cells (+++P < 0.001). Significant difference of the antioxidant activities of the two compounds was evidently connected with the different position of the methyl group. The protective effect of OA was in HL-60 cells slightly lower compared to the activity of UA, but the difference between the protective effects of UA and OA was not significant. In conclusion we can say that both natural pentacyclic triterpenoic acids investigated, UA and OA, manifested potent antioxidant effects. The different position of one methyl group in their chemical structures caused moderately different biological activities of these compounds on three leukemic cell lines. To explore their mechanisms of action further investigation seems to be therefore worthwhile.  相似文献   

3.
Bacterial resistance to antibiotics is increasing at an alarming rate and many commonly used antibiotics are no longer effective. Thus, there is considerable interest in investigating novel antibacterial compounds, such as the plant-derived pentacyclic triterpenoids, including oleanolic acid (OA), ursolic acid (UA) and their derivatives. These compounds can be isolated from many medicinal and crop plants and their antibacterial, antiviral, antiulcer and anti-inflammatory effects are well documented. OA and UA are active against many bacterial species, particularly Gram-positive species, including mycobacteria. They inhibit bacterial growth and survival, and the spectrum of minimal inhibitory concentration (MIC) values is very broad. In addition, OA, UA and their derivatives display potent antimutagenic activity. Studies to identify the cellular targets and molecular mechanisms of OA and UA action were initiated a few years ago and it has already been demonstrated that both acids influence bacterial gene expression, the formation and maintenance of biofilms, cell autolysis and peptidoglycan turnover. Before these compounds can be used clinically as antimicrobial agents, further extensive studies are required to determine their cytotoxicity and the optimum mode of their application.  相似文献   

4.
Salvia triloba (Greek sage) has been used for the treatment of various diseases and contains two bioactive triterpene acids of major interest: oleanolic acid (OA) and ursolic acid (UA). The determination of the solubility of OA and UA in different solvents is a prerequisite to select the optimal solvent. The main goal of this work was to develop a quick method of predicting the solubility of OA/UA in different solvents to get a first indication of which solvents could be considered suitable for extraction from any plant material containing at least one of these triterpenes. A novel and simple ultra-violet spectroscopy method was developed for this purpose.The best solubilities were determined in THF, dioxane and n-butanol as well as in blends of dioxane and n-butanol.  相似文献   

5.
Esterification of glycyrrhetinic acid (GA) with dehydrozingerone (DZ) resulted in a novel cytotoxic GA-DZ conjugate. Based on this exciting finding, we conjugated eleven different DZ analogs with GA or other triterpenoids, including oleanoic acid (OA) or ursolic acid (UA). In an in vitro anti-cancer assay using nine different human tumor cell lines, most of the GA-DZ conjugates showed significant potency. Particularly, compounds 5, 29, and 30 showed significant cytotoxic effects against LN-Cap, 1A9, and KB cells with ED(50) values of 0.6, 0.8, and 0.9 microM, respectively. Similar conjugates between DZ and OA or UA were inactive suggesting that the GA component is critical for activity. Notably, although GA-DZ conjugates showed potent cytotoxic activity, the individual components (GA and DZ analogs) were inactive. Thus, GA-DZ conjugates are new chemical entities and represent interesting hits for anti-cancer drug discovery and development.  相似文献   

6.
The bisdesmoside oleanolic acid saponin, 3-0-(methyl-beta-D-glucuronopyranosiduronoate)-28-0-beta-D-glucopyranosyl-oleanolate along with nine known compounds (two diterpenic acids, one chromene, three triterpenes, one steroidal glycoside, and two monodesmoside oleanolic acid saponins), were obtained from Viguiera decurrens roots. The chemical structure of the bisdesmoside oleanolic saponin was determined by chemical and NMR spectral evidence. A mixture of monodesmoside saponins displayed cytotoxic activity against P388 and COLON cell lines (ED50= 2.3 and 3.6 microg/ml, respectively). Two of the known compounds showed insecticidal activity against the Mexican bean beetle larvae (Epilachna varivestis).  相似文献   

7.
The present work was aimed at the influence of ethanol on the complex formation of hydroxypropyl-β-cyclodextrin (HP-β-CD) with oleanolic acid (OA) and ursolic acid (UA), two insoluble isomeric triterpenic acids. Phase solubility studies were carried out to evaluate the solubilizing power of HP-β-CD, in association with ethanol, toward OA and UA. A mathematical model was applied to explain and predict the solubility of OA and UA influenced by HP-β-CD and ethanol. The solid complexes were prepared by evaporating the filtrate of samples which was prepared in different complexing media. The solubility of OA is much higher than that of UA in all the tested aqueous solutions. The solubility of OA and UA can be increased over 900 and 200 times, respectively, by forming complex with HP-β-CD. Ethanol (0.5%, v/v) can help the formation of OA-HP-β-CD complex, but is harmful to the formation of UA-HP-β-CD complex. Increasing solubility in water can be achieved by adding ethanol into the complexing media, but the concentration of ethanol should be optimized. The ring E of the chemical compounds has a great influence on the complexing process.  相似文献   

8.
Viral entry inhibitors are of great importance in current efforts to develop a new generation of anti-influenza drugs. Inspired by the discovery of a series of pentacyclic triterpene derivatives as entry inhibitors targeting the HA protein of influenza virus, we designed and synthesized 32 oleanolic acid (OA) analogues in this study by conjugating different amino acids to the 28-COOH of OA. The antiviral activity of these compounds was evaluated in vitro. Some of these compounds revealed impressive anti-influenza potencies against influenza A/WSN/33 (H1N1) virus. Among them, compound 15a exhibited robust potency and broad antiviral spectrum with IC50 values at the low-micromolar level against four different influenza strains. Hemagglutination inhibition (HI) assay and docking experiment indicated that these OA analogues may act in the same way as their parent compound by interrupting the interaction between HA protein of influenza virus and the host cell sialic acid receptor via binding to HA, thus blocking viral entry.  相似文献   

9.
The aim of this work was to use in vivo models to evaluate the analgesic and anti-inflammatory activities of ursolic acid (UA) and oleanoic acid (OA), the major compounds isolated as an isomeric mixture from the crude methylene chloride extract of Miconia albicans aerial parts in an attempt to clarify if these compounds are responsible for the analgesic properties displayed by this plant. Ursolic acid inhibited abdominal constriction in a dose-dependent manner, and the result obtained at a content of 40 mg kg(-1) was similar to that produced by administration of acetylsalicylic acid at a content of 100 mg kg(-1). Both acids reduced the number of paw licks in the second phase of the formalin test, and both of them displayed a significant anti-inflammatory effect at a content of 40 mg kg(-1). It is noteworthy that the administration of the isolated mixture, containing 65% ursolic acid/35% oleanolic acid, did not display significant analgesic and anti-inflammatory activities. On the basis of the obtained results, considering that the mixture of UA and OA was poorly active, it is suggested that other compounds, rather than UA and OA, should be responsible for the evaluated activities in the crude extract, since the crude extract samples displayed good activities.  相似文献   

10.
Functional triterpenic acids such as ursolic acid (UA), oleanolic acid (OA) and betulinic acid (BA) are representative ingredients in rosemary that may have health benefits. UA, OA and BA in rosemary extracts were derivatized with 4‐(4,5‐diphenyl‐1H‐imidazole‐2‐yl)benzoyl chloride (DIB‐Cl) and detected using HPLC‐fluorescence (FL). Dried rosemary (50 mg) was ground, added to 3 ml of ethanol, sonicated for 40 min, then the sample solution was added to a mixture of 1% trimethylamine and 1 mM DIB‐Cl in acetonitrile. The mixture was settled for 5 min at room temperature, then the DIB‐triterpenic acid derivatives were separated using a Wakopak Handy ODS column (250 × 4.6 mm, 6 μm) eluted with 25 mM acetate buffer (pH 4.5)/methanol/acetonitrile (= 8:10:82 v/v/v%). The fluorescence intensity of the eluent was monitored at 365 (λex) and 490 nm (λem) and the maximum retention time of the derivatives was 30 min. Calibration curves constructed using rosemary extract spiked with standards showed good linearity (r ≥ 0.997) in the range 2.5–100 ng/ml. The detection limits at 3σ for internal BA, UA and OA peaks in rosemary extract were 0.2, 0.4 and 0.5 ng/ml, respectively. This method was used to quantify BA, UA and OA in commercially available dried rosemary products.  相似文献   

11.
BackgroundIsomeric ursolic acid (UA) and oleanolic acid (OA) compounds have recently garnered great attention due to their biological effects. Previously, it had been shown that UA and OA can exert important pharmacological action via the protein kinase C (PKC) and nuclear factor-κB (NF-κB) signaling, and that they can induce the expression of UDP-glucuronosyltransferase 1A1 (UGT1A1) in HepG2 cells. This study aims to investigate the role of PKC/NF-κB signaling in regulating the expression of UGT1A1 and examine how UA and OA induce UGT1A1 based on this signaling pathway.MethodsHepG2 cells, hp65-overexpressed HepG2 cell and lentivirus-hp65-shRNA silenced HepG2 cells were stimulated with PKC/NF-κB specific agonists and inhibitors for 24 h in the presence or absence of UA and OA. The expression of UGT1A1, PKC, and NF-κB were determined by qRT-PCR, western blot, and dual-luciferase reporter gene assays.ResultsPKC/NF-κB activation downregulates UGT1A1 expression. This effect is countered by UA and OA treatment. Phorbol 12-myristate 13-acetate (PMA) and lipopolysaccharide (LPS), the agonists of PKC and NF-κB signaling, respectively, significantly inhibit hp65-mediated UGT1A1 luciferase activity. UA, OA, and the PKC/NF-κB inhibitors suppress this effect. PMA and LPS do not affect UGT1A1 activity in p65-silenced HepG2 cells; however, UA and OA mildly influence UGT1A1 expression in these cells.ConclusionThe activation of PKC/NF-κB signaling can significantly downregulate UGT1A1 expression. By inhibiting the PKC/NF-κB signaling pathway, UA and OA promote UGT1A1 expression in HepG2 cells.  相似文献   

12.
Present study deals with the microwave assisted extraction (MAE) of ursolic acid (UA) and oleanolic acid (OA) from Ocimum sanctum leaves. UA and OA have been reported to possess significant medicinal properties. Various experimental parameters such as selection of solvent, solvent composition, irradiation time, microwave power, solid to solvent ratio, preleaching time and number of cycles were investigated to optimize the extraction process. Under optimum conditions of irradiation time (3 min), microwave power (272 W), solid to solvent ratio (1:30), preleaching time (10 min), maximum UA and OA has been extracted in one extraction cycle with ethanol: water (80:20) as a solvent. Maximum 86.76 and 89.64% of UA and OA was extracted under above mentioned optimized experimental conditions. MAE was also compared with the batch and ultrasound assisted extraction (UAE) method. As compared to batch and UAE, higher extraction yield of these important phytochemicals have been obtained through MAE in only 3 min.  相似文献   

13.
A xanthone derivative, named gaboxanthone (1), has been isolated from the seed shells of Symphonia globulifera, together with known compounds, symphonin (2), globuliferin (3), guttiferone A (4), sistosterol, oleanolic acid and methyl citrate. The structure of the compound was assigned as 5,10-dihydroxy-8,9-dimethoxy-2,2-dimethyl-12-(3-methylbut-2-enyl) pyrano [3,2-b]xanthen-6(2H)-one, by means of spectroscopic analysis. The anti-plasmodial and antioxidant activities of the phenolic compounds were evaluated, respectively, in culture against W2 strain of Plasmodium falciparum and using the free radical scavenging activity of the DPPH radical, respectively. Compounds 1-4 were found to be active against the Plasmodium parasites (IC(50) of 3.53, 1.29, 3.86 and 3.17 microM, respectively). Guttiferone A (4) showed a potent free radical scavenging activity compared to the well-known antioxidant caffeic acid.  相似文献   

14.
Antibiotic resistance among bacterial pathogens is a serious problem for human and veterinary medicine, which necessitates the development of novel therapeutics and antimicrobial strategies. Some plant-derived compounds, e.g. pentacyclic triterpenoids such as oleanolic acid (OA) and ursolic acid (UA), have potential as a new class of antibacterial agents as they are active against many bacterial species, both Gram-positive and Gram-negative, and specifically target the cell envelope. The aim of the present study was to investigate the influence of OA and UA on the susceptibility of four bacterial pathogens (Pseudomonas aeruginosa, Listeria monocytogenes, Staphylococcus aureus and Staphylococcus epidermidis) to the β-lactam antibiotics ampicillin (Ap) and oxacillin (Ox). Antimicrobial assays were conducted with bacteria growing in liquid suspension cultures (planktonic cells) or as biofilms. Using FICI value estimation and the time-kill method it was demonstrated that in some combinations, the tested compounds acted in synergy to lower the susceptibility of S. aureus, S. epidermidis and L. monocytogenes to ampicillin and oxacillin, but no synergy was observed for P. aeruginosa. These results indicate that OA and UA may be useful when administered in combination with β-lactam antibiotics to combat bacterial infections caused by some Gram-positive pathogens.  相似文献   

15.
The infusion of the aerial parts of Gentianella multicaulis (Gillies ex Griseb.) Fabris (Gentianaceae), locally known as 'nencia', is used in San Juan Province, Argentina, as stomachic and as a bitter tonic against digestive and liver problems. The bioassay-guided isolation of G. multicaulis extracts and structural elucidation of the main compounds responsible for the antifungal and free radical scavenging activities were performed. The extracts had strong free radical scavenging effects in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay (45-93% at 10 microg/mL) and ferric-reducing antioxidant power (FRAP) assay at 200 microg/mL. Demethylbellidifolin (4) had high antioxidant activity in the DPPH and FRAP assay. The dermatophytes Microsporum gypseum, Trichophyton mentagrophytes, and T. rubrum were moderately inhibited by the different extracts (MIC values of 125-250 microg/mL). Demethylbellidifolin (4), bellidifolin (5), and isobellidifolin (6) showed an antifungal effect (MIC values of 50 microg/mL), while swerchirin (3) was less active with a MIC value of 100 microg/mL. In addition, oleanolic acid (1) and ursolic acid (2) were also isolated. These findings demonstrate that Gentianella multicaulis collected in the mountains of the Province of San Juan, Argentina, is an important source of compounds with antifungal and antioxidant activities.  相似文献   

16.
Kim KA  Lee JS  Park HJ  Kim JW  Kim CJ  Shim IS  Kim NJ  Han SM  Lim S 《Life sciences》2004,74(22):2769-2779
Oleanolic acid (OA) and ursolic acid (UA), triterpene acids having numerous pharmacological activities including anti-inflammatory, anti-cancer, and hepato-protective effects, were tested for their ability to modulate the activities of several cytochrome P450 (CYP) enzymes using human liver microsomes. OA competitively inhibited CYP1A2-catalyzed phenacetin O-deethylation and CYP3A4-catalyzed midazolam 1-hydroxylation, the major human drug metabolizing CYPs, with IC50 (Ki) values of 143.5 (74.2) microM and 78.9 (41.0) microM, respectively. UA competitively inhibited CYP2C19-catalyzed S-mephenytoin 4'-hydroxylation with an IC50 (Ki) value of 119.7 (80.3) microM. However, other CYPs tested showed no or weak inhibition by both OA and UA. The present study demonstrates that OA and UA have inhibitory effects on CYP isoforms using human liver microsomes. It is thus likely that consumption of herbal medicines containing OA or UA, or administration of OA or UA, can cause drug interactions in humans when used concomitantly with drugs that are metabolized primarily by CYP isoforms. In addition, it appears that the inhibitory effect of OA on CYP1A2 is, in part, related to its anti-inflammatory and anticancer activities.  相似文献   

17.
Triterpene acids (ursolic, oleanoic, gypsogenic, and sumaresinolic acids) isolated from Miconia species, along with a mixture of ursolic and oleanolic acids and a mixture of maslinic and 2-a-hydroxyursolic acids, as well as ursolic acid derivatives were evaluated against the following microorganisms: Streptococcus mutans, Streptococcus mitis, Streptococcus sanguinis, Streptococcus salivarius, Streptococcus sobrinus, and Enterococcus faecalis, which are potentially responsible for the formation of dental caries in humans. The microdilution method was used for the determination of the minimum inhibitory concentration (MIC) during the evaluation of the antibacterial activity. All the isolated compounds, mixtures, and semi-synthetic derivatives displayed activity against all the tested bacteria, showing that they are promising antiplaque and anticaries agents. Ursolic and oleanolic acids displayed the most intense antibacterial effect, with MIC values ranging from 30 microg/mL to 80 microg/mL. The MIC values of ursolic acid derivatives, as well as those obtained for the mixture of ursolic and oleanolic acids showed that these compounds do not have higher antibacterial activity when compared with the activity observed with either ursolic acid or oleanolic acid alone. With regard to the structure-activity relationship of triterpene acids and derivatives, it is suggested that both hydroxy and carboxy groups present in the triterpenes are important for their antibacterial activity against oral pathogens.  相似文献   

18.
The inhibiting activity of triterpenoids isolated from the methanolic extract of Pourouma guianensis (Moraceae) leaves is described for promastigotes and intracellular amastigotes of Leishmania amazonensis. Whereas the fractions containing apigenin, friedelin, epi-friedelinol, arjunolic acid, hyptatic acid B, stigmasterol and sitosterol were of no or relatively low inhibitory activity, fractions containing tormentic acid, 2alpha,3beta-dihydroxyursan-12-en-28-oic acid, 2alpha,3beta-dihydroxyolean-12-en-28-oic acid, oleanolic acid and ursolic acid were very potent in inhibiting promastigote growth at 100 microg/ml. Of the eleven isolated compounds, however, only ursolic acid and oleanolic acid showed high activity against intracellular amastigotes (IC50 value = 27 microg/ml and 11 microg/ml, respectively), which was superior to the control drug Glucantime (IC50 value = 83 microg/ml). The antileishmanial activity of oleanolic acid was directed against the parasite and not due to activation of nitric oxide intermediates by macrophages, but this triterpenoid also significantly inhibited the phagocytic capacity of those cells at concentrations above 40 microg/ml, indicating a cytotoxic effect. These results indicate that Pourouma guianensis contains many triterpenoids and some, such as ursolic and oleanolic acids, may serve as lead compounds for new antileishmanial drugs, but chemical modifications may be necessary to avoid unselective cytotoxicity.  相似文献   

19.
Prunella vulgaris L. is an important medicinal plant with a variety of pharmacological activities, but limited information is available about its response to potassium chloride (KCl) supplementation. P. vulgaris seedlings were cultured in media with four different KCl levels (0, 1.00, 6.00 and 40.00 mM). Characteristics relating to the growth, foliar potassium, water and chlorophyll content, photosynthesis, transpiration, nitrogen metabolism, bioactive constituent concentrations and yield were determined after three months. The appropriate KCl concentration was 6.00 mM to result in the highest values for dry weight, shoot height, spica and root weight, spica length and number in P. vulgaris. The optimum KCl concentration resulted in a maximum net photosynthetic rate (Pn) that could be associated with the highest chlorophyll content and fully open stomata conductance. A supply of surplus KCl resulted in a higher concentration of foliar potassium and negatively correlated with the biomass. Plants that were treated with the appropriate KCl level showed a greater capacity for nitrate assimilation. The Pn was significantly and positively correlated with nitrate reductase (NR) and glutamine synthetase (GS) activities and was positively correlated with leaf-soluble protein and free amino acid (FAA) contents. Both KCl starvation (0 mM) and high KCl (40.00 mM) led to water loss through a high transpiration rate and low water absorption, respectively, and resulted in increased concentrations of ursolic acid (UA), oleanolic acid (OA) and flavonoids, with the exception of rosmarinic acid (RA). Moreover, the optimum concentration of KCl significantly increased the yields of RA, UA, OA and flavonoids. Our findings suggested that significantly higher plant biomass; chlorophyll content; Pn; stronger nitrogen anabolism; lower RA, UA, OA and flavonoid accumulation; and greater RA, UA, OA and flavonoid yields in P. vulgaris could be expected in the presence of the appropriate KCl concentration (6.00 mM).  相似文献   

20.
The cardiotonic and antidysrhythmic effects of four triterpenoid derivatives, namely oleanolic acid (OA), ursolic acid (UA), and uvaol (UV), isolated from the leaves of African wild olive (Olea europaea, subsp. africana) as well as methyl maslinate (MM) isolated from the leaves of Olea europaea (Cape cultivar) were examined. The derivatives showed low toxicity on brine shrimp test. They displayed significant, dose-response vasodepressor effect and sinus bradicardia, most prominent for OA and MM. The derivatives acted as beta-adrenergic antagonists, blocking the effect of adrenaline and isoprenaline. The established positive inotropic and dromotropic effects were most distinctive for OA and MM. The antidysrhythmic effects were evaluated on CaCl2- and adrenaline-induced chemical arrhythmias, and on ischemia-reperfusion arrhythmia. OA and UA displayed antidysrhythmic effects on both types of chemical arrhythmia; OA and UV in dose 40 mg/kg conferred significant antidysrhythmic activity on ischemia and reperfusion arrhythmias. The effect was comparable to that of propranolol and suggestive of beta-adrenergic antagonistic activity. On the basis of the vasodepressor, cardiotonic and antidysrhythmic effects of these compounds, it was concluded that OA and UV isolated from wild African olive leaves, or crude extract containing all components, can provide a cheap and accessible source of additive to conventional treatment of hypertension, complicated by stenocardia and cardiac failure.  相似文献   

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