首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The active compounds from Forsythia suspense were screened for antioxidant activities in vitro and lowering blood lipid and lipid peroxidation in vivo. Five compounds, ursolic acid, phillygenin, (+)-pinoresinol, and quercetin, from EtOAC extract and rutin from n-BuOH extract were isolated and identified by spectroscopic methods. Phillygenin and (+)-pinoresinol had notable scavenging activity against DPPH, ABTS radicals, as well as potent reducing power in FRAP assay in vitro. Intragastric administration of EtOAC extract (500 mg/kg body weight per day), ursolic acid (150 mg/kg), phillygenin (150 mg/kg), and rutin (70 mg/kg) to groups of hyperlipidemia mice for 10 days significantly decreased the level of blood triglyceride and the level of low-density lipoprotein cholesterol (P < 0.001) in serum. However, the level of blood high-density lipoprotein cholesterol in the same treated mice decreased slightly (P > 0.05). The level of hepatic malondialdehyde (MDA, an index of lipid peroxidation) was assayed to evaluate the mechanism(s) of EtOAC extract, ursolic acid, phillygenin, and rutin. Under hyperlipidemia condition, the level of hepatic MDA increased. After intragastric administration of EtOAC extract, ursolic acid, phillygenin, and rutin, the level of hepatic MDA significantly decreased. The result showed that EtOAC extract, ursolic acid, phillygenin, and rutin had a high hypolipidemic activity and this activity may be attributed to their antioxidant potential.  相似文献   

2.
A series of novel hybrid molecules between sulfonamides and active antimicrobial 14‐o‐(3‐carboxy‐phenylsulfide)‐mutilin were synthesized, and their in vitro antibacterial activities were evaluated by the broth microdilution. Results indicated that these compounds displayed potent antimicrobial activities in vitro against various drug‐susceptible and drug‐resistant Gram‐positive bacteria such as Staphylococci and streptococci, including methicillin‐resistant Staphylococcus aureus, and mycoplasma. In particular, sulfapyridine analog ( 6c ) exhibited more potent inhibitory activity against Gram‐positive bacteria and mycoplasma, including Staphylococcus aureus (MIC = 0.016–0.063 μg/mL), methicillin‐resistant Staphylococcus aureus (MIC = 0.016 μg/mL), Streptococcus pneumoniae (MIC = 0.032–0.063 μg/mL), Mycoplasma gallisepticum (MIC = 0.004 μg/mL), with respect to other synthesized compounds and reference drugs sulfonamide (MIC = 8–128 μg/mL) and valnemulin (MIC = 0.004–0.5 μg/mL). Furthermore, comparison between MIC values of pleuromutilin‐sulfonamide hybrids 6a–f with pleuromutilin parent compound 3 revealed that these modifications at 14 position side chain of the pleuromutilin with benzene sulfonamide could greatly improve the antibacterial activity especially against Gram‐positives.  相似文献   

3.
Using bioisosterism as a medicinal chemistry tool, 16 3,5‐diaryl‐isoxazole analogues of the tetrahydrofuran neolignans veraguensin, grandisin and machilin G were synthesized via 1,3‐dipolar cycloaddition reactions, with yields from 43% to 90%. Antitrypanosomatid activities were evaluated against Trypanosoma cruzi, Leishmania (L.) amazonensis and Leishmania (V.) braziliensis. All compounds were selective for the Leishmania genus and inactive against T. cruzi. Isoxazole analogues showed a standard activity on both promastigotes of L. amazonensis and L. braziliensis. The most active compounds were 15 , 16 and 19 with IC50 values of 2.0, 3.3 and 9.5 μM against L. amazonensis and IC50 values of 1.2, 2.1 and 6.4 μM on L. braziliensis, respectively. All compounds were noncytotoxic, showing lower cytotoxicity (>250 μM) than pentamidine (78.9 μM). Regarding the structure–activity relationship (SAR), the methylenedioxy group was essential to antileishmanial activity against promastigotes. Replacement of the tetrahydrofuran nucleus by an isoxazole core improved the antileishmanial activity.  相似文献   

4.
《Saudi Pharmaceutical Journal》2020,28(10):1197-1202
The aim of this work is to evaluate the chemical constituents and potential biological activists of Cunninghamella blakesleeana. Three fatty acids were isolated using column chromatography and identified as palmitic acid (F1), oleic acid (F2) and stearic acid (F3) in addition to other two steroidal compounds; α-amyrin (A4), and β-sitosterol (A5). Using GC, ten fatty acids were detected the major fatty acid obtained was stearic acid (74.61%) while palmitic acid was the second high percentage (10.35%), and the least percentage obtained was arachidic acid (0.07%). C. blakesleeana extract showed in-vitro antimicrobial activities against some microorganisms. The highest activity of C. blakesleeana total extract was reported against Staphylococcus aureus (18.3 ± 0.03 mm.) followed by Streptococcus pyogenes (15.3 ± 0.05), while the lowest were for both Candida albicans & Pseudomonas aeruginosa (6.7 ± 0.06 and 5.9.0 ± 0.9 mm. respectively). The three isolated compounds (F1-3) showed activities against Staphylococcus aureus, Penicillium expansum, and Salmonella typhimurium only. The highest activity was aganist Staphylococcus aureus (13.0 ± 0.1 mm.). The highest effect was obtained by compound F3 (stearic acid) (15.0 ± 0.5 mm.), and compound F1 (oleic acid) (13.0 ± 0.1 mm.) and F2 (palmitic acid) 11.0 ± 0.3 mm. The total ethanol extract of the investigated fungus was safe up to 5000 mg kg−1 and did not produce any significant change in liver and kidney functions after oral administration (400 mg kg−1) for 14 consecutive days. The results reported the isolation of some fungal new driving compounds which has been not isolated before from Cunninghamella species in addition to their correlated new biological activities.  相似文献   

5.
6.
This investigation was aimed to probe the pharmacological base of medicinal use of Acorus calamus in ischemic heart diseases. Effect on heart parameters was studied in isolated rabbit heart while coronary vasodilator effect was studied in isolated bovine coronary arterial rings, suspended in tissue baths filled with Krebs solution, maintained at 37°C, aerated with carbogen and responses were measured on PowerLab data acquisition system. In Langendorrf’s perfused rabbit heart, the crude extract of Acorus calamus (Ac.Cr) at 0.01–10 mg/mL partially suppressed force of ventricular contractions (FVC), heart rate (HR) and coronary flow (CF). The ethylacetate fraction completely suppressed FVC, partially suppressed HR and CF, while the nHexane fraction exhibited similar effect on FVC and HR but increased CF, similar to methacholine and arachidonic acid. In bovine coronary arterial preparations, Ac.Cr caused inhibition of U46619 (20 nM)-precontractions, which was blocked in presence of increasing concentration of K+ (4.8–20 mM), tetraethylammonium (1 μM) and SKF525A (10 μM), similar to arachidonic acid and methacholine, indicating K+ channels activation and possible involvement of endothelial-derived hyperpolarizing factor (EDHF). Activity-directed fractionation revealed that EDHF-mediated activity is concentrated in the nHexane fraction. When tested against high K+, the ethylacetate fraction was found more potent than parent crude extract and nHexane fraction. These data indicate that Ac.Cr mediates coronary vasodilator effect primarily through EDHF, responsible for the increase in CF, while the cardiac depressant effects may be due to the presence of additional cardiac depressant constituent(s), thus provides possible mechanistic basis to its medicinal use in ischemic heart diseases.  相似文献   

7.
Dermatomycoses are among the most widespread and common superficial and cutaneous fungal infections in humans. There is an urgent need to develop efficient and non‐toxic antimycotic agents with a specific spectrum of activity. Triterpenes have been demonstrated to exhibit a wide range of biological activities, including antifungal activities. In this study, through hemisynthesis, we aimed to obtain triterpene‐isosteric molecules from betulinic and ursolic acids to improve the antifungal activity and spectrum of action of these compounds. Six compounds were resynthesized and tested against eleven mucocutaneous and cutaneous mycotic agents. The results of the susceptibility assays were expressed as the minimal inhibitory concentration (MIC). The MIC values of the piperazinyl derivatives of ursolic and betulinic acids that were active against pathogenic yeasts were in the range of 16–32 μg/mL and 4–16 μg/mL, respectively, whereas fungicidal effects were observed at concentrations ranging from 16 to 128 μg/mL and 8 to 128 μg/mL, respectively. The piperazinyl derivative of betulinic acid exhibited an antifungal profile similar to that of terbinafine and was the most effective derivative against dermatophytes. This strategy led to a promising candidate for the development of a new antifungal agent.  相似文献   

8.
Two series of novel salicylanilide were synthesized as potential epidermal growth factor receptor (EGFR) inhibitors. The enzyme inhibitory activity against EGFR of all compounds was carried out, and their antiproliferative activities against the A549 and A431 cell lines were also evaluated. Of the compounds studied, majority of them exhibited high antiproliferative activities compared with gefitinib; especially, 12a and 12b exhibited stronger inhibitory activity against EGFR with IC50 values of 10.4 ± 2.25 and 15.4 ± 2.33 nm , respectively, which were comparable to the positive control of gefitinib (IC50 = 12.1 ± 2.21 nm ). Compound 12b also showed outstanding inhibitory activity against A431 and A549 cell lines with the IC50 values of 0.42 ± 0.43 μm and 0.57 ± 0.43 μm , which was better than the positive controls. In the molecular modeling study, compound 12b was bound into the active pocket of EGFR with two hydrogen bond and with minimum binding free energy ▵Gb = −25.1125 kcal/mol. The result also suggested that compound 12b could bind the EGFR kinase well.  相似文献   

9.
In this study, 30 hydrazide–hydrazones of phenylacetic ( 3 – 10 ) and hydroxyacetic acid ( 11 – 32 ) were synthesized by the condensation reaction of appropriate 2‐substituted acetic acid hydrazide with different aromatic aldehydes. The obtained compounds were characterized by spectral data and evaluated in vitro for their potential antimicrobial activities against a panel of reference strains of micro‐organisms, including Gram‐positive bacteria, Gram‐negative bacteria, and fungi belonging to the Candida spp. The results from our antimicrobial assays indicated that among synthesized compounds 3 – 32 , especially compounds 6 , 14, and 26 showed high bactericidal activity (MIC = 0.488–7.81 μg/ml) against reference Gram‐positive bacteria, and in some cases, their activity was even better than that of commonly used antibiotics, such as cefuroxime or ampicillin.  相似文献   

10.
An acute (96 h—0.1, 0.5, 1.0, 1.5 μg/ml) and chronic (up to 30 days—0.05 μg/ml) protocols of Cu and Zn were applied to freshwater fish Oreochromis niloticus to investigate these essential metal effects on the activities of gill, kidney and muscle Na+/K+-ATPase, Mg2+-ATPase and Ca2+-ATPase. In vitro effects of both metals (20 min—0.1, 0.5, 1.0, 1.5 μg/ml) were also measured to be able to compare both exposure routes. Data showed that ATPase activities, in general, decreased following all the exposure conditions, though there were some increases especially in Mg2+-ATPase activity. Among the enzymes, Na+/K+-ATPase and Ca2+-ATPase appeared to be more sensitive than Mg2+-ATPase to the metals. The data also indicated that effects of Cu on ATPase activity in the tissues of O. niloticus were stronger than the effects of Zn, possibly due to higher toxic effects of Cu. In vivo and in vitro exposures of metals showed similar trends with a few exceptions, especially in the gill. Variability of ATPase activity is determined by tissue type, metal species, concentration and duration. This work showed that even essential metals can alter significantly activities of ATPases in fish and thus suggests using them as a sensitive biomarker in metal contaminated waters.  相似文献   

11.
The objective of this study was to investigate the effects of ascorbic acid on the toxicity of cypermethrin's on histopathological lesions in tissues and protein, glycogen levels in Oreochromis niloticus. Nile tilapia was exposed to 0.22 and 0.44 μg/l cypermethrin + control diet, 0.22 and 0.44 μg/l cypermethrin + ascorbic acid supplemented diet for 20 days. The fish were allowed recuperation period of 15 days in pesticide-free water and fed with ascorbic acid suplementation diet. In light microscopic investigation, histopathological lesions were observed in the gill, liver and kidney. The severity of lesions accreted depending on increased pesticide concentration and control diet. Some of the lesions were reversible or at least were less pronounced after recuperation period. Protein levels decreased in some groups after treatment period according to control groups (p < 0.05). The highest depletions in liver, muscle and gill protein levels were found in 0.44 μg/l cypermethrin + ascorbic acid supplemented diet group (62.23%), in 0.22 μg/l cypermethrin + control diet group (53.12%) and in 0.44 μg/l cypermethrin + control diet group (61.87%) after 10 days, respectively. These levels increased at the end of the recuperation period. The highest depletion in liver glycogen levels was found in 0.22 μg/l cypermethrin + control diet group (50.50%) after 10 days (p < 0.05). At the end of recuperation period, there was no difference between the groups (except 0.22 μg/l cypermethrin + ascorbic acid supplemented diet group) and controls. The decrease of muscle glycogen, except 0.22 μg/l cypermethrin + ascorbic acid supplemented diet group, was recorded at the end of 10 and 20 days. In the recuperation period, an increase was observed at all groups. These results revealed that the histopathology, protein and glycogen can work as good indicators of stress of a toxicant on fish. Ascorbic acid serves fish as an antitoxic agent against pesticide toxicity.  相似文献   

12.
Feleucins-BV1 and -BV2 are recently described prototypes of a novel antimicrobial non-apeptide (AMP) family identified in the skin secretion of the bombinid toad, Bombina variegata. They are encoded on different precursors that also encode a novel bombinin. Here we describe the identification of feleucin-BO1 (FLGLLGSLLamide) which is co-encoded with a different novel bombinin, named feleucin precursor-associated bombinin (FPA-bombinin-BO), from the skin secretion of Bombina orientalis. Synthetic feleucin-BO1 displayed activity against a reference Gram-positive bacterium. Staphylococcus aureus (MIC 34 μm ) but was inactive (> 250 μm ) against the Gram-negative bacterium, Escherichia coli, and the yeast, Candida albicans. This pattern of activity was similar to that of the prototypes. Design and synthesis of a cationicity-enhanced analogue, feleucin-K3 (F-K3), in which the amino acid residues at positions 3 (G), 6 (G) and 7 (S) of feleucin-BO1 were substituted with Lys (K) residues, resulted in a peptide with significantly enhanced potency and spectrum of activity. The MICs of F-K3 against the reference micro-organisms were 7 μm (S. aureus), 14 μm (E. coli) and 7 μm (C. albicans). These data indicate that the skin secretions of amphibians can continue to provide novel peptide templates for the rational design of analogues with possible therapeutic utility.  相似文献   

13.
Mentha spicata is a well-known spice that has a variety of biological properties and is abundantly available throughout the world. This study was designed to investigate the superoxide radical scavenging and antibacterial properties of different fractions (hexane, chloroform, ethyl acetate, and aqueous) of the ethanol extract of Mentha spicata. In addition, xanthine oxidase generated uric acid inhibition, reducing potential and iron chelating activity, also was investigated. Ethyl acetate fraction exhibited the highest (≤84%) superoxide radical scavenging and inhibition of uric acid formation at 40 μg/ml compared with the standard quercetin (≤81%) at 30 μg/ml. The highest reducing potential also is observed in ethyl acetate and aqueous fractions, which were comparable to the reducing potential of quercetin and ascorbic acid. Iron chelating activity of solvent fractions was found to be better than standard of EDTA (79% at 3 mg/ml). In addition, all fractions showed effective antibacterial activity against five human pathogenic bacteria among the ten samples used. However, aqueous fraction showed maximum growth inhibition zone (≤36 mm diameter at 6 μg/per disc) against Shigella boydii. Hence, we conclude that the ethyl acetate and aqueous fractions of ethanol extract of Mentha spicata exhibited higher superoxide radical scavenging and antibacterial activities.  相似文献   

14.
A series of scutellarein carbamate derivatives were designed and synthesized based on the multitarget‐directed drug design strategy for treatment of Alzheimer's disease. Their acetylcholinesterase and butyrylcholinesterase inhibitory activities, antioxidant activities, metals chelation, and neuroprotective effects against hydrogen peroxide‐induced PC12 cell injury were evaluated in vitro. The preliminary results indicated that compound 7b exhibited good inhibitory potency toward AChE and BuChE with IC50 values of 1.2 ± 0.03 μm and 22.1 ± 0.15 μm , respectively, possessed the strong antioxidant potency (10.3 trolox equivalents), as well as acted as a selective metal chelator and neuroprotective agent. Furthermore, 7b could improve memory impairment induced by scopolamine, ethanol, and sodium nitrite using the step‐down passive avoidance task in vivo and could remarkably decrease the activity of acetylcholinesterase in mice brain. This study indicated that 7b could be considered as a potential multitarget agent against AD.  相似文献   

15.
Cisplatin (CDDP) is an important chemotherapeutic agent, accumulation of which in kidney tissue causes nephrotoxicity and renal failure. The aim of this study was to evaluate, for the first time in the literature, the protective effect of dimethyl sulfoxide (DMSO) extract of Primula vulgaris leaf (PVE) against CDDP-induced nephrotoxicity in rats.The PVE content was characterized using liquid chromatography-mass spectrometry. Nephrotoxicity was induced with a single dose of CDDP (7.5 mg/kg). Thirty female Wistar-Albino rats were divided into five groups (control, DMSO, CDDP (7.5 mg/kg), CDDP + PVE (25 mg/kg), and CDDP + PVE (50 mg/kg)). Biochemical and histopathological analyses were then performed.Rutin, gallic acid, p-coumaric acid and protocatechuic acid were identified as major components of PVE. Total antioxidant status and glutathione (GSH) values increased significantly in the serum samples from the treatment group compared to the CDDP group, while blood urea nitrogen, creatinine, oxidative stress index, malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), total oxidant status, and 8-hydroxy-2′-deoxyguanosine (8-OHdG) values decreased significantly. GSH levels increased significantly in the treatment group compared to the CDDP group, while TNF-α, caspase-3, 8-OHdG, MDA levels and damage scores decreased significantly.In conclusion, PVE exhibited strong protective effects through its anti-apoptotic, antioxidant, and anti-inflammatory activities against nephrotoxicity and oxidative damage caused by CDDP in rats.  相似文献   

16.
Seven Morchella species were analyzed for their antioxidant activities in different test systems namely β-carotene/linoleic acid, DPPH, reducing power, chelating effect and scavenging effect (%) on the stable ABTS+, in addition to their heavy metals, total phenolic and flavonoid contents. In β-carotene/linoleic acid system, the most active mushrooms were M. esculenta var. umbrina and M. angusticeps. In the case of DPPH, methanol extract of M. conica showed high antioxidant activity. The reducing power of the methanol extracts of mushrooms increased with concentration. Chelating capacity of the extracts was also increased with the concentration. On the other hand, in 40 μg ml−1 concentration, methanol extract of M. conica, exhibited the highest radical scavenging activity (78.66 ± 2.07%) when reacted with the ABTS+ radical. Amounts of seven elements (Cu, Mn, Co, Zn, Fe, Ca, and Mg) and five heavy metals (Ni, Pb, Cd, Cr, and Al) were also determined in all species. M. conica was found to have the highest phenolic content among the samples. Flavonoid content of M. rotunda was also found superior (0.59 ± 0.01 μg QEs/mg extract).  相似文献   

17.
A series of novel di‐ and tripeptidyl epoxyketone derivatives composed of β‐amino acids were designed, synthesized and evaluated for their proteasome inhibitory activities and anti‐proliferation activities against two multiple myeloma cell lines RPMI 8226 and NCI‐H929 and normal cells (peripheral blood mononucleated cells). Among these tested compounds, tripeptidyl analogues showed much more potent activities than dipeptides, and four tripeptidyl compounds exhibited proteasome inhibitory activities with IC50 values ranging from 0.97 ± 0.05 to 1.85 ± 0.11 μm . In addition, all the four compounds showed anti‐proliferation activities with IC50 values at low micromolar levels against two multiple myeloma cell lines and weak activities against normal cells. Furthermore, Western blot analysis was performed to verify the proteasome inhibition induced by compounds 21d and 21e . All the experimental results validated that the β‐amino acid building block has the potential for the development of proteasome inhibitors.  相似文献   

18.
A series of novel derivatives of strictosamide were synthesized and biologically evaluated. Most of the new compounds exhibited improved activities than the parent compound strictosamide. Among them, compounds Ib and If possessed antiviral activities against influenza A virus (A/Jinan/15/90) with IC50 values of 4.12 and 12.35 μg/mL, respectively. Compound Ie possessed antiviral activity against respiratory syncytial virus (RSV) with an IC50 value of 9.58 μg/mL. Both compounds IIc and IId had moderate antiproliferative effects against five human cancer cell lines. The preliminary structure‐activity relationships were also concluded. This study provides a promising new template with potential antiviral activity.  相似文献   

19.
A novel series of 2‐hydroxy‐3‐(nitroimidazolyl)‐propyl‐derived quinolones 6a – o were synthesized and evaluated for their in vitro antibacterial activity. Most of the target compounds exhibited potent activity against Gram‐positive strains. Among them, moxifloxacin analog 6n displayed the most potent activity against Gram‐positive strains including S. epidermidis (MIC = 0.06 μg/mL), MSSE (MIC = 0.125 μg/mL), MRSE (MIC = 0.03 μg/mL), S. aureus (MIC = 0.125 μg/mL), MSSA (MIC = 0.125 μg/mL), (MIC = 2 μg/mL). Its activity against MRSA was eightfold more potent than reference drug gatifloxacin. Finally, docking study of the target compound 6n revealed that the binding model of quinolone nucleus was similar to that of gatifloxacin and the 2‐hydroxy‐3‐(nitroimidazolyl)‐propyl group formed two additional hydrogen bonds.  相似文献   

20.
A new series of indole appended dihydronaphthalenone hybrid analogs ( 5a–t ) have been synthesized through the Lewis acid catalyzed Michael addition of indoles to the arylidene/hetero arylidene ketones. All the synthesized derivatives are well characterized through the 1H‐NMR, 13C‐NMR, HRMS spectroscopic techniques, compound 5r was further confirmed through single crystal X‐ray analysis and screened for antibacterial and antitubercular activities. Among the synthesized compounds, the minimum inhibition concentration of 5l (against Escherichia coli) and 5o & 5p (against E. coli & Staphylococcus aureus) was found to be as low as 3.12 μg/ml as compared to the standard antibacterial drug ciprofloxacin 2.5 μg/ml. In antitubercular activity, compounds 5o and 5p with minimum inhibition concentration 6.25 μg/ml were found to be comparable with that of the drugs Pyrazinamide 5 μg/ml and Streptomycin 5 μg/ml. Compounds 5i , 5j , 5m , 5n , 5q , and 5r also showed promising activity against group of organisms tested.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号