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991.
Robert Brus Dalibor Ballian Faruk Bogunić Martin Bobinac Marilena IdžOjtić 《Plant biosystems》2013,147(2):278-285
Abstract In most European countries, the service tree (Sorbus domestica L.) is a rare and threatened species and its conservation has been recognised as a priority. The aim of this study was to asses its morphologic variation in the western and central part of the Balkan Peninsula and in southern Central Europe. Three populations were analysed: one in Serbia, one in Bosnia and Herzegovina and one in Slovenia. In each population 30 trees were selected, and from each tree 30 leaves were collected for morphometric analysis based on nine leaflet morphological traits. Univariate (ANOVA) and multivariate (MANOVA) analysis of variance were used to estimate the variation within- and between populations and a discriminant analysis was performed to examine the structure of the between-population differences. The values of particular morphological traits found in our study did not differ considerably from the values reported elsewhere. The results revealed significant within- and between population variation. Variation within populations was highly significant for all the scored leaf morphological traits, while variation between populations was significant for all the studied traits except for the leaflet length. The discrimination between the three populations was significant. High percentages of correctly classified samples demonstrate good discriminating employability of the analysed leaf morphological traits and indicate differentiation of the analysed populations. 相似文献
992.
Lucas R. Brun Aneley Traverso 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):691-696
Intestinal alkaline phosphatase (IAP) is an enzyme of the brush border of the enterocyte. The activity of IAP biphasically depends on calcium. Although calcium increases IAP activity, when calcium is higher than 20 mmole/L, IAP activity decreases and the amount of an aggregated form increases. The reversibility of the effect of calcium and the aggregation process are unknown. The isoelectric point of the enzyme was higher in the presence of calcium, but was the same for the enzyme and the aggregated form. The treatment with EGTA after calcium addition did not restore the enzymatic activity but produced desaggregation of the enzyme and increase in the monomeric subunits of IAP. It is concluded that the binding of calcium does not produce important modifications on the structure of the protein, that the inhibitory effect is not reversible and that calcium could be involved in the stability of the structure of the enzyme. 相似文献
993.
Natarajan Suganthy Shanmugiahthevar Karutha Pandian 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):702-707
Alzheimer's disease is a progressive neurodegenerative illness accounting for approximately 50% of all types of dementia in elderly people. The only symptomatic treatment proven effective to date is the use of cholinesterase inhibitors to augment surviving cholinergic activity. The purpose of this study is to investigate cholinesterase inhibitory activity of mangroves as an alternative medicine for the treatment of Alzheimer's disease. About nine mangrove plants, which were used as folk medicine in tropical countries, were collected from Parangipettai, Vellar estuary, Tamilnadu, India. Nile Tilapia muscle homogenate was used as source of enzyme. Inhibitory effect of methanolic leaf extract was assessed under in vitro condition by incubating various concentration of the extract with total cholinesterase and butyryl cholinesterase and assessing their residual activities by Ellman's colorimetric method. The results showed that of the nine plants screened Rhizophora lamarckii, Suaeda monica, Avicennia officinalis and Sesuvium portulacastrum showed 50% inhibitory activity to both TChE and BChE at concentrations less than 2 mg/mL when compared to other plant extracts, which was comparable to the standard drug Donepezil. Phytochemical analysis showed the presence of alkaloids in high concentration which might be correlated to its cholinesterase inhibitory activity. 相似文献
994.
Bashir Ahmad S. M Mukaram Shah Shumaila Bashir Halima Begum 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):136-139
The crude methanolic extract and subsequent fractions of Teucrium royleanum (Labiatea) were screened for antibacterial and antifungal activities. Against tested pathogens, crude extract and subsequent fractions demonstrated moderate to excellent antibacterial activities. Highest antibacterial activity was displayed by the ethyl acetate fraction against S. typhi (100%), against E.coli (76.7%) and against P. aerugenosa (70.8%) followed by the chloroform fraction against S. typhi (85.7%). Similarly, the crude extract and its subsequent fractions showed mild to excellent activities in the antifungal bioassay with maximum antifungal activity against M. canis (87%) by the chloroform fraction followed by the ethyl acetate (71%) and n-butanol (70%) fractions. 相似文献
995.
Rosa Tundis Federica Menichini Filomena Conforti Monica R. Loizzo Marco Bonesi Giancarlo Statti 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):818-824
From the aerial parts of Salsola oppositofolia, S. soda and S. tragus an alkaloid extract was obtained and tested to evaluate antioxidant and anti-cholinesterase activities. The in vitro study of the antioxidant activity by the DPPH method revealed a significant activity of Salsola alkaloid extracts with IC50 values ranging from 16.30 μg/mL for S. oppositifolia to 26.17 μg/mL for S. tragus. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were evaluated. S. tragus alkaloid extract exerted the highest inhibitory activity against AChE (IC50 of 30.2 μg/mL) and BChE (IC50 of 26.5 μg/mL). Interestingly, S. soda and S. oppositifolia exhibited a selective inhibitory activity against BChE with IC50 values of 34.3 μg/mL and 32.7 μg/mL, respectively. Tetrahydroisoquinoline alkaloids were identified and quantified by GC/MS analysis. 相似文献
996.
Manuel Medarde Ana B.S. Maya Concepción Pérez-Melero 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):521-540
Synthesis and evaluation of new combretastatin analogues with varied modifications on the bridge and the aromatic rings, have shown that the 2-naphthyl moiety is a good surrogate for the 3-hydroxy-4-methoxyphenyl (B-ring) of combretastatin A-4. Other bicyclic systems, such as 6(7)-quinolyl and 5-indolyl, can replace the B-ring, but they produce less potent analogues in the cytotoxicity and tubulin polymerization inhibition assays. Other modifications are detrimentral for the potency of the studied analogues. The 2-naphthyl combretastatin 53 and the related 6-quinolyl combretastatin 106 analogues are the most potent among the derivatives of this type, whereas 92 and 95 are the most potent among the naphthalene derivatives with a heterocycle in the bridge. Previous and new results in this family of combretastatin analogues are discussed. 相似文献
997.
Alexandra Testard Laurent Picot Ingrid Fruitier-Arnaudin Jean-Marie Piot Hadjila Chabane Lisianne Domon 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):467-473
Novel 6-substituted thiazolocarbazole derivatives have been synthesized under microwave irradiation via the corresponding imino-1,2,3-dithiazoles. In vitro antitumor potential of these polyheterocyclic compounds was evaluated. Among all the tested thiazolocarbazoles, compound 10 is the most effective in inhibiting cell growth. 相似文献
998.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):749-753
A carbonic anhydrase (CA, EC 4.2.1.1) from red blood cells of pigeons (Columba livia var. domestica), clCA, was purified to homogeneity. Its kinetic parameters for the CO2 hydration reaction were measured. With a kcat/Km of 1.1?×?108 M?1 s?1, and a kcat of 1.3?×?106 s?1, clCA has a high activity, similar to that of the human isoform hCA II. A group of 25 aromatic/heterocyclic sulfonamides incorporating the sulfanilamide, homosulfanilamide, benzene-1,3-disulfonamide, and acetazolamide scaffolds showed variable inhibitory activity against the pigeon enzyme, with KIs in the range of 1.9–3460?nM. Red blood cells of pigeons, like those of ostriches, contain thus just one CA isoform, unlike the blood of mammals, which normally contain two isoforms, one of low (CA I-like) and one of very high activity (CA II-like). However, from the sulfonamide inhibition viewpoint, the pigeon enzyme was more similar to hCA II than to the ostrich enzyme. 相似文献
999.
N. Gheibi A.A. Saboury K. Haghbeen F. Rajaei A.A. Pahlevan 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):1076-1081
Catecholase and cresolase activities of mushroom tyrosinase (MT) were studied in presence of some n-alkyl carboxylic acid derivatives. Catecholase activity of MT achieved its optimal activity in presence of 1.0, 1.25, 2.0, 2.2 and 3.2?mM of pyruvic acid, acrylic acid, propanoic acid, 2-oxo-butanoic acid, and 2-oxo-octanoic acid, respectively. Contrarily, the cresolase activity of MT was inhibited by all type of the above acids. Propanoic acid caused an uncompetitive mode of inhibition (Ki=0.14?mM), however, the pyruvic, acrylic, 2-oxo-butanoic and 2-oxo-octanoic acids showed a competitive manner of inhibition with the inhibition constants (Ki) of 0.36, 0.6, 3.6 and 4.5?mM, respectively. So, it seems that, there is a physical difference in the docking of mono- and o-diphenols to the tyrosinase active site. This difference could be an essential determinant for the course of the catalytic cycle. Monophenols are proposed to bind only the oxyform of the tyrosinase. It is likely that the binding of acids occurs through their carboxylate group with one copper ion of the binuclear site. Thus, they could completely block the cresolase reaction, by preventing monophenol binding to the enzyme. From an allosteric point of view, n-alkyl acids may be involved in activation of MT catecholase reactions. 相似文献
1000.
A. J. Nok B. A. Sallau E. Onyike N. M. Useh 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):365-368
The diterpenoid furanolactone (columbin) from Aristolochia albida inhibited growth of culture forms of Trypanosoma brucei. In vitro analysis of the compound at 5–250 μg/ml showed complete lysis of the parasites within 10–20 minutes post incubation. At 50 μg/ml, columbin killed about 50% of the parasites which initially appeared swollen under phase contrast microscopy. Also the total amount of cholesterol diminished dose-dependently in the presence of 10–100 μg/ml of columbin after a 3-day incubation period.In vivo analysis of the compound in T. brucei-infected mice revealed that 25 mg/kg administered for 3 consecutive days, completely cleared the parasites from the peripheral circulation. However, columbin could not clear parasites in the cerebrospinal fluid. 相似文献