Hemorrhagic activity of the Duvernoy''s gland secretion of the xenodontine colubrid Philodryas patagoniensis from the north-east region of Argentina

Colubrid snakes belonging to Philodryas genus, widespread all over South America, bring about lesions (swelling, ecchymosis, transient bleeding from the bite site punctures), that are similar to those produced by Bothrops species (yarará). In the present work we began the characterization of Philodryas patagoniensis venom. We examined if this venom produces hemorrhagic lesions as those observed in victims bitten by Philodryas olfersii. Hemorrhagic, proteolytic and fibrinogenolytic activities were evaluated, and histological observations in samples of gastrocnemius muscle were carried out. Inhibition studies were carried out in metal chelator (ethylenediaminetetraacetic acid) presence. Our results show a small Minimum Hemorrhagic Dose (MHD=0.035 μg) and a high proteolytic activity (143 U/mg), and prove the capacity of this venom to degrade fibrinogen in vitro rendering it unclottable by thrombin, supporting the presence of proteases, principally metalloproteases, in P. patagoniensis venom that are able to alterate the vascular wall and degrade fibrinogen, being both activities responsible of a high hemorrhagic activity.     

Antimicrobial activity of 5-arylidene aromatic derivatives of hydantoin. Part 2

Various 5-chloroarylidene-2-amino substituted derivatives of imidazoline-4-one were synthesized and evaluated for their activity in vitro against Mycobacterium tuberculosis and other type strains of bacteria and fungi. 2-Chloro- and 2,4-dichlorobenzylidene substituted hydantoins exhibited antimycobacterial effect. The most potent compounds 3i, 3j, 3o, 3q and 3s were classified for further tests. The antimitotic effect of the investigated hydantoins was also examined.     

Synthesis of new thiazolylthiazolidinylbenzothiazoles and thiazolylazetidinylbenzothiazoles as potential insecticidal, antifungal, and antibacterial agents

A series of 2-{[2'-(3'-chloro-2'-oxo-4'-substitutedaryl-1'-azetidinyl)-1',3'-thiazol-4'-yl] thio}benzothiazoles (4a-4e) and 2-{[(2'-(2'-substitutedaryl-4'-thiazolidinon-3'-yl)-1',3'-thiazol-4'-yl]thio}benzothiazoles (5a-5e) have been synthesized from 2-[(2'-substitutedarylidenylimino-1',3'-thiazol-4'-yl)thio]benzothiazoles (3a-3e). The structure of these compounds has been elucidated by elemental (C, H, N) and spectral (IR, (1)H-NMR, Mass) analysis. Furthermore, compounds 3a-3e, 4a-4e, and 5a-5e were screened for insecticidal activity against Periplaneta americana and antifungal, antibacterial activities in vitro against different strains of fungi and bacteria. Out of the fifteen compounds tested, compound 5b, 2-{[2'-(2'-p-hydroxy-m-methoxyphenyl)-4'-thiazolidinon-3'-yl)-1',3'-thiazol-4'-yl]thio}benzothiazole, was found to possess most prominent insecticidal activity.     

Evaluation of the Antimicrobial Activity of Ammoniacum Gum from Dorema ammoniacum

Antimicrobial activity of the dichloromethane-methanol (1 : 1) extract of ammoniacum gum (from Dorema ammoniacum D. Don) was evaluated against 14 microorganisms which included seven Gram-positive bacteria (Bacillus cereus, Bacillus pumilus, Bacillus subtilis, Micrococcus luteus, Staphylococcus epidermidis, Staphylococcus aureus and Streptococcus faecalis), four Gram-negative bacteria (Escherichia coli, Pseudomonas aereuginosa, Klebsiella pneumoniae and Bordetella bronchiseptica), one yeast (Saccharomyces cereviseae) and two fungi (Aspergillus niger and Candida albicans). The extract of ammoniacum gum exhibited a of broad spectrum antimicrobial activity by inhibiting all the seven Gram-positive bacterium, one Gramnegative bacterium, one yeast and one fungus, with a minimum inhibitory concentration (MIC) of 40µg/ml. To overcome the solubility problem often faced when herbal extracts are added to aqueous medium, we employed a modified broth method where the broth cultures were agitated at 150 rpm in an orbital shaking incubator. This method reduced the MIC of the extract considerably, to 5-20µg/ml, against B. bronchiseptica, S. aureus and S. epidermidis.     

Antinociceptive,anti-inflammatory,and antioxidant properties of Phoradendron piperoides leaves

Phoradendron piperoides (Kunth) Trel. (Viscaceae) is a parasitic plant widely distributed in regions of the Brazilian northeast. Different species of Phoradendron are used in folk medicine for the treatment of cough, influenza, gastrointestinal and female disorders, and pain. In order to evaluate the actions of this plant, studies were performed on antinociceptive, anti-inflammatory, and antioxidant activities. The methanol extract (ME) and dichloromethane, ethyl acetate, and methanol partitions of P. piperoides leaves were used in the following experiments. Oral treatment with the ME elicited inhibitory activity (p?<?0.01) on the acetic acid effect at 100 (32.08%), 200 (34.46%), and 400?mg/kg (49.50%). P. piperoides ME reduced the formalin effect at the second phase (200 and 400?mg/kg, p?<?0.05); however, the ME did not elicit any inhibitory effect on the hot-plate test. Edema formation induced by carrageenan was reduced (p?<?0.05) with the ME by 28% (200?mg/kg) and 33% (400?mg/kg). ME, dichloromethane, ethyl acetate, and methanol partitions reacted with the DPPH radical and reduced the DPPH radical by 94.5, 37.2, 77.2, and 95.7%, respectively. ME, ethyl acetate, and methanol partitions exhibited low IC₅₀ values.     

Anti-inflammatory,Antinociceptive, and Neuropharmacological Activities of Clerodendron viscosum.

Abstract

The crude methanol extract of Clerodendron viscosum. Vent. (Verbenaceae) leaves was evaluated for its anti-inflammatory, antinociceptive, and neuropharmacological activities. When given orally to rats at doses of 200 and 400 mg/kg of body weight, the extract showed a significant (p < 0.001) anti-inflammatory activity against carrageenan-induced rat paw edema comparable with the standard drug phenylbutazone at the dose of 100 mg/kg of body weight. It also produced a significant writhing inhibition in acetic acid–induced writhing in mice at the oral dose of 250 and 500 mg/kg of body weight (p < 0.001), which was comparable with the standard drug diclofenac sodium at the dose of 25 mg/kg of body weight. Moreover, when given intraperitoneally to albino mice, it potentiated the pentobarbital-induced sleeping time (p < 0.001), decreased the open field score in open field test (p < 0.001), decreased the number of holes crossed from one chamber to the other in the hole-cross test (p < 0.001), and decreased the head dip responses in the hole-board test (p < 0.001) at the dose of 250 and 500 mg/kg of body weight. The overall results tend to suggest the anti-inflammatory, antinociceptive, and central nervous system depressant activities of the crude methanol extract of Clerodendron viscosum..     

Post-antibacterial effect of thymol

The antibacterial activity of thymol has been well established and reported in the scientific literature. Continued suppression of bacterial growth following limited exposure to antimicrobial compounds at different concentrations greater than or equal to the minimum inhibitory concentration level (MIC) and at concentrations less than the MIC can be used as an indicator of biological activity, and are respectively referred to as a post-antibacterial effect (PAE) and a post-antibiotic sub-MIC effect (PA-SME). In this study, the PAE and the PA-SME of thymol against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus cereus were investigated. A spectrophotometric method was used to determine the PAE and the PA-SME of thymol against the selected test strains. Thymol exhibited a considerable PAE and PA-SME at MIC and sub-MIC concentrations against test strains. The greatest duration of both the PAE and the PA-SME was observed for thymol against E. coli and P. aeruginosa. The PAE and PA-SME times for E. coli were 12 and 8?h, respectively, and for P. aeruginosa were 11 and 7.5?h, respectively. The duration of the PAE and PA-SME observed for S. aureus and B. cereus was shorter than for Gram-negative strains.     

Antioxidant and antimicrobial activities of branches extracts of five Juniperus species from Turkey

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.     

SV预防血栓药理学作用及其机制研究探讨

血栓栓塞性疾病是人类首要致死病因,临床预防血栓药物均存在出血危险。选择性的内源性凝血途径抑制剂已成为低出血倾向预防血栓药物研发的重点方向。SV是以天然岩藻糖化糖胺聚糖(FG)为先导化合物经结构优化获得的选择性内源性凝血因子Xase抑制剂(IC50=30 nm),其抑制内源性凝血活性与依诺肝素相当,在等效抗凝血剂量的倍数剂量下出血倾向显著降低。本文探讨低出血倾向的SV预防血栓药理学作用及其机制,为选择性Xase抑制剂及其新药发现研究提供参考依据。     

羊栖菜多糖活性研究评述

目的：阐述羊栖菜多糖的主要药用活性以及作用机制。方法：检索查阅近年相关的实验文献资料,并进行归纳总结。结果：羊栖菜多糖在抗肿瘤、影响免疫功能、降血糖、降血脂等方面有显著的药理作用,并且毒副作用小。结论：羊栖菜多糖药用价值大,具有非常广阔的应用前景。     

Structure-antibacterial,antitumor and hemolytic activity relationships of cecropin A-magainin 2 and cecropin A-melittin hybrid peptides

In order to elucidate the structure-antibiotic activity relationship of cecropin A-magainin 2 and cecropin A-melittin hybrid peptides, several truncated peptides and the analogues with amino acid substitutions were synthesized and their antibacterial, antitumor and hemolytic activities of were examined. Cecropin A-magainin 2 hybrid analog, L¹⁶-CA(1–8)-MA(1–12) (termed as L-CA-MA in this study: KWKLFKKIGIGKFLHLAKKF-NH₂), is known to have potent antibacterial and antitumor activity with less hemolytic activity. We found that the C-terminal region of L-CA-MA is more involved in the α-helical structure on cell membrane-like environment than N-terminal one by circular dichroism analysis. Deletion of the Gly-lle-Gly sequence, the central hinge region of L-CA-MA, produced a considerable reduction in antitumor and hemolytic activity rather than an antibacterial one. The insertion of Pro, Gly-lle or Gly-Pro in this hinge region of L-CA-MA caused retention of both antibacterial and antitumor activity while causing a significant decrease in hemolytic activity. However, the substitution with Gly-Pro-Gly instead of the Gly-lle-Gly in CA(1–8)-MA(1–12), CA(1–8)-ME(1–12), CA(1–13)-MA(1–13) and CA(1–13)-ME(1–13) hybrids resulted in a drastic decrease in antibacterial, antitumor and hemolytic activity. The increase of hydrophobicity at position 16 in CA(1–8)-MA(1–12) by substituting Trp or Phe induced a significant increase in hemolytic activity without a considerable change in either antibacterial or antitumor activity. Therefore, these results suggested that the appropriate flexibility in the hinge region of CA-MA and CA-ME hybrid peptides and the appropriate hydrophobicity at position 16 in the hydrophobic region of CA (1–8)-MA(1–12) are important in potent antibacterial and antitumor activity with no hemolytic effect.     

小檗胺抗炎活性的实验研究(英)

本文研究了小檗胺的抗炎活性,结果表明小檗胺在25mg·kg-1·7d和50mg·kg-1·7·d剂量下对由角叉菜胶诱导的大鼠足趾肿胀及高岭土诱导的大鼠关节炎具有明显的抑制作用。实验提示小檗胺可能具有明显的抗炎活性。     

Chemical constituents and bioactivities of the liposoluble fraction from different medicinal parts of Crocus sativus

Context: Crocus sativus Linn. (Iridaceae), commonly known as saffron, becomes more and more popular due to its versatile biological and medicinal properties. At present, studies mainly focus on the traditional medicinal part, the saffron stigma, with less attention to the other parts of saffron, such as the perianth, the stamen, and the corm, which are high yield compared to the stigma and also possess various pharmacological effects.

Objective: To determine the chemical compositions, antifungal, cytotoxic, and antioxidant activities of the ether fractions from the stamen, perianth, and stigma of saffron.

Materials and methods: The chemical constituents of the ether fractions from different parts of saffron were investigated by gas chromatography/mass spectrometry. Several pathogenic fungi isolates and tumor cell lines were employed to evaluate the antifungal and cytotoxic activities of these three ether fractions. 1,1-Diphenyl-2-picrylhydrazyl assay was used to determine the free radical-scavenging activity.

Results: The ether fractions composition of the three C. sativus parts are different from each other, but lauric acid, hexadecanoic acid, 4-hydroxydihydro-2(3H)-furanone, and stigmasterol were the common constituents shared by all the three fractions. The stamen ether fraction displayed the strongest antifungal and cytotoxic activities, whereas both of the saffron stamen and perianth ether fractions exhibited significant antioxidant activities.

Discussion and conclusion: These findings demonstrate that the saffron stamen and perianth possess significant antifungal, cytotoxic, and antioxidant activities as well as the stigma, though not to the same extent, prompting us to expand the medicinal resource and make best use of this valuable plant.     

Synthesis and biological evaluation of new thiazolopyrimidines

In this study, a series of 4-amino-5-cyano-3-substituted-2,3-dihydrothiazol-2-thiones (1a-c), as well as their triazolo and triazinopyrimidine derivatives such as 8-substituted-3-benzyl-5-methylthiazolo[5,4-e][1,2,4] triazolo[1,5-c]pyrimidin-2-thiones (4-6, 10) and 3-benzyl-5-methyl thiazolo[5,4-e]pyrimidino[3,4-b][1,2,4]triazin-2-thiones (7a-b) were prepared as potential antimicrobial and antitumor agents. Some of the tested compounds showed promising antimicrobial activity and non of them showed any appreciable antitumor activity.     

Investigation of the antimicrobial and anticancer activity of aminonaphthoquinones

In this study, we report on the inhibitory activity of synthesized aminonaphthoquinones against two bacterial and one fungal species to determine their antimicrobial properties. A minimum inhibitory concentration (MIC) of 7.8 μg/mL was obtained against the fungus, Candida albicans, which was better than that of Amphotericin B (MIC = 31.25 μg/mL). Escherichia coli (Gram -), was inhibited at a MIC of 23.4 μg/mL and Staphylococcus aureus (Gram +) at a MIC of 31.3 μg/mL. The aminonaphthoquinones were also screened against HCT116 colon, PC3 prostate and HepG2 liver cancer cell lines to evaluate their cytostatic effects. They had potent activity (GI₅₀ = 5.87–9.90 μM) which was about three-6-fold better than that of parthenolide (GI₅₀ = 25.97 μM) against the prostate cancer cell line. These compounds were generally more selective for cancer cells than for normal human lung fetal fibroblasts (WI-38).     

Antipyretic, analgesic and anti-inflammatory effects of delta 9-tetrahydrocannabinol in the rat

The effects on body temperature produced by graded doses of Δ⁹-tetrahydrocannabinol (Δ⁹-THC) and phenylbutazone were compared in both normal and pyretic rats. Dose related hypothermic responses were produced by the oral administration of Δ⁹-THC in normal animals. Moreover, Δ⁹-THC significantly reduced elevated temperatures in yeast-induced pyretic rats to near normal levels at doses which exhibited little hypothermic activity in normal rats. The oral antipyretic potency of Δ⁹-THC was approximately 2 times that of phenylbutazone. The comparative oral antinociceptive activity of Δ⁹-THC and selected narcotic and non-narcotic analgesics was determined by the increase in response latency to pressure applied to normal and yeast-inflamed paws. Δ⁹-THC administered orally was essentially inactive at dose levels below those producing pronounced central nervous system depression. The oral anti-inflammatory efficacy of Δ⁹-THC was compared to phenylbutazone and acetylsalicylic acid. Δ⁹-THC was ineffective in inhibiting carrageenin-induced edema of the rat paw following acute or chronic administration.     

Antifertility Activity of Stems of Plumbago rosea in Female Albino Rats

In the present study, Plumbago rosea Linn. (Plumbaginaceae), one of the folk medicinal plants commonly used as an antifertility agent, was evaluated for its antifertility effect. Five successive solvent extracts, petroleum ether, chloroform, acetone, ethanol, and water extracts, of the stems of P. rosea were studied on estrous cycle at two dose levels, 200 and 400 mg/kg respectively. Of these, the acetone extract was found to be most effective in interrupting the normal estrous cycle of rats (p < 0.05) (p < 0.01). The rats exhibited prolonged diestrous stage of the estrous cycle with consequent temporary inhibition of ovulation. The antiovulatory activity was reversible on withdrawal of the extract. The effective acetone extract was further studied on estrogenic functionality in rats. The acetone extract showed significant estrogenic and antiestrogenic activity (p < 0.05) (p < 0.001). Histological studies of the uteri further confirmed the estrogenic activity of acetone extract. The results indicated the antifertility activity of stems of Plumbago rosea in female Wistar rats.     

Evaluation of metal concentration and antioxidant,antimicrobial, and anticancer potentials of two edible mushrooms Lactarius deliciosus and Macrolepiota procera

This study is designed for the determination of metal concentrations, antioxidant, antimicrobial, and anticancer potential of two edible mushrooms Lactarius deliciosus and Macrolepiota procera. Concentrations of nine metals are determined and all metals are present in the allowable concentrations in the tested mushrooms except Cd in M. procera. Antioxidant activity was evaluated by free radical scavenging and reducing power. M. procera extract had more potent free radical scavenging activity (IC₅₀ = 311.40 μg/mL) than L. deliciosus extract. Moreover, the tested extracts had effective reducing power. The total content of phenol in the extracts was examined using Folin–Ciocalteu reagent and obtained values expressed as pyrocatechol equivalents. Further, the antimicrobial potential was determined with a microdilution method on 15 microorganisms. Among the tested species, extract of L. deliciosus showed a better antimicrobial activity with minimum inhibitory concentration values ranging from 2.5 mg/mL to 20 mg/mL. Finally, the cytotoxic activity was tested using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method on human epithelial carcinoma HeLa cells, human lung carcinoma A549 cells, and human colon carcinoma LS174 cells. Extract of both mushrooms expressed similar cytotoxic activity with IC₅₀ values ranging from 19.01 μg/mL to 80.27 μg/mL.     

Synthesis of prenylated and geranylated xanthones and their bioactivities

Nine prenylated and geranylated xanthones were synthesized in two steps with total yields ranging from 11% to 36%. All of the compounds were first reported. Then, the antitumor, anti-tyrosinase, anti-pancreatic lipase,antifungal and antibacterial activities of all or part of compounds 1–9 were evaluated. Compound 9 exhibited clear antitumor activity, and its cytotoxicity against MCF-7 and MDA-MB-231 cells was stronger compared with cisplatin. Compounds 1–4 and 6–7 alsoexhibited certain activity other than the antitumor activity described above. These results demonstrated that compounds 1–4, 6–7and 9 were very promising leads for further structural modification.