bluuebunny/crossref_metadata_2025 huggingface dataset:
Screening of nine vasoactive medicinal plants for their possible calcium antagonistic activity. Strategy of selection and isolation for the active principles of Olea europaea and Peucedanum ostruthium
Authors: Rauwald H. W. , Brehm O. , Odenthal K. P.
Published: October 2006

Fourteen different extracts of nine vasoactive medicinal plants used in European and African phytotherapy and traditional medicine were pharmacologically tested for their possible calcium antagonistic mode of action. The criteria for the selection of plants were: use in traditional medicine in the treatment of cardiovascular diseases, ‘nonspecific’ spasmolytic activity (mode of action not known), natural compounds with structural similarities to already known ‘calcium‐antagonists’ or calcium‐antagonists that have been found in species of the same tribe. All plant extracts were investigated against contractions of aortic strips induced by K+‐depolarization. Extracts derived from Ammi visnaga, Guajacum officinale, Olea europaea, Peucedanum ostruthium and Ruta graveolens showed a clear activity, while Cryptolepis sanguinolenta, Leonurus cardiaca, Passiflora incarnata and Solidago gigantea showed no effect in this test. A comparison between K+‐ and norepinephrine‐induced contractions evaluated the selectivity of the inhibition, which is demonstrated by the isolation and identification strategy for the Ca++‐antagonistic principles of Olea europaea leaves and Peucedanum ostruthium rhizomes.
Antiprotozoal activity of quinoline alkaloids isolated from Galipea longiflora, a Bolivian plant used as a treatment for cutaneous leishmaniasis
Authors: Fournet A. , Barrios A. Angelo , Muñoz V. , Hocquemiller R. , Roblot F. , Cavé A. , Richomme P. , Bruneton J.
Published: October 2006

The stem bark of Galipea longiflora is used by the Chimane Indians in Bolivia for the treatment of cutaneous leishmaniasis produced by Leishmania braziliensis. Petroleum ether and chloroform extracts of stem, root bark and leaves were found active in vitro against Leishmania ssp and Trypanosoma cruzi at 100 μg/mL. The activity guided fractionation of the extracts by chromatography afforded 12 active compounds identified as 2‐substituted quinoline alkaloids. BALB/c mice were infected with Leishmania amazonensis (strain PH8 or H‐142) and treated 24 h after infection with the major alkaloids from the crude alkaloidal extract; 2‐phenylquinoline and 2‐n‐pentylquinoline. 2‐phenylquinoline was as potent as Glucantime (Rhǒne‐Poulenc) against the strain H‐142, but less active than the reference drug against the virulent strain PH8 of L. amazonensis. 2‐n‐pentylquinoline did not exhibit any activity. Assays of single local treatments on the rear footpad infection, 2 weeks after the parasitic inoculation, indicated an effect for 2‐phenylquinoline by reducing the severity of lesion. However, this activity was found to be slightly lower than that obtained using Glucantime.
Studies on possible protective effect of plant derived phenols and the vitamin precursors—β‐Carotene and α‐tocopherol on 7,12 dimethylbenz (a) anthracene induced tumour initiation events
Authors: Moushumi Lahiri , Sumati Bhide
Published: October 2006

Our earlier experiments have shown that the plant phenols—hydroxychavicol, eugenol, catechin, curcumin, and the vitamins—β‐carotene and α‐tocopherol—are potent inhibitors of polycyclic aromatic hydrocarbon (PAH) induced mutagenesis and carcinogenesis. In an attempt to elucidate their mode of action, we studied their effect on mouse skin DNA synthesis following 7,12 dimethylbenzanthracene (DMBA) treatment and 3H‐7,12 dimethylbenzanthracene—DNA interaction in vitro (in the presence of mouse skin S9). With the exception of eugenol, all the phenols and vitamins tested inhibited 3H‐DMBA‐DNA interaction in vitro. In the DNA biosynthesis assay, of the chemopreventive agents tested only β‐carotene effectively modulated DMBA suppressed DNA synthesis in the mouse skin. Our results indicate that the assay of DNA biosynthesis is not of predictive value with respect to the chemopreventive effect of a chemical, while assay of carcinogen—DNA interaction shows correlation between the chemopreventive property and the inhibition of the interaction of carcinogen with DNA.
Isolation of a neuromuscular junctional blocking agent from Cleistanthus collinus plant leaf extract
Authors: Vijayalakshmi K. M. , Kumar N. V. Nanda , Pagala M. K. D.
Published: October 2006

A potent neuromuscular junctional blocking agent was isolated from chloroform extracts of poisonous Cleistanthus collinus leaf by a combined chromatographic—cholinesterase inhibition technique. An amorphous yellowish green extract was eluted from paper or micro thin layer chromatographic plates. This compound caused a 93% fade on nerve evoked muscle tension and a 95% decrement in nerve evoked muscle action potentials and least change in muscle evoked muscle action potentials and tension in a rat phrenic nerve—diaphragm preparation, suggesting the presence of a potent pharmacologically active ingredient causing neuromuscular blockade which is irreversible.
The ethanol‐insoluble fraction of an aqueous Cervi Cornu Vernum extract improves the condition of renal anaemia in rats fed an adenine diet
Authors: Yokozawa Takako , Ogama Takako , Namba Tsuneo , Hattori Masao
Published: October 2006

Levels of red blood cell count (RBC), haemoglobin (Hb) and haematocrit (Ht) were decreased significantly in rats fed an adenine diet. Their erythrocyte indices, such as mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC), were similar to those of normal rats, but uraemic symptoms were present as well, providing evidence of renal anaemia. Administration of the EtOH‐insoluble fraction of an aqueous extract of Cervi Cornu Vernum improved the renal anaemia, and the changes were reflected in the morphology of the erythrocytes. Furthermore, there was a significant increase in total protein and albumin. These findings suggest that the EtOH‐insoluble fraction of Cervi Cornu Vernum improves the state of undernutrition resulting from renal anaemia.
Cholertic activity of Thapsia chem I, II, and III in rats: Comparison with terpenoid constituents and peppermint oil
Authors: Trabace Luigia , Avato Pinarosa , Mazzoccoli Michele , Siro‐Brigiani Giovanni
Published: October 2006

The influence on bile flow of the fruit essence from three chemotypes of the genus Thapsia and their major components has been investigated. For comparative purposes menthol and peppermint oil were also included in the assay. All the drugs tested showed toa different extent choleretic activity calculated on the increase of the bile amount in male adbult Wistar rats. Thapsia Chem I (50 mg/kg) containing 88% geranylacetate was found to indued choleresis in treated rats to a level as high as peppermint oil containing 42% menthol. A similar activity was confirmed when pure geranylacetate was assayed.
Pharmacological effects of butylidenephthalide
Authors: Ko Wun‐Chang , Chang Li‐Duang , Wang Gwo‐Yang , Lin Lung‐Ching
Published: October 2006

The pharmacological effects of synthetic butylidenephthalide (Bdph), the most potent antispasmodic agent found in the neutral oil of Ligusticum wallichii Franch., were examined in this study. In vivo, Bdph exerted a significant antihypertensive effect in anaesthetized renal hypertensive rats at a dose of 30 mg/kg (i.v. or i.p.), or 60 mg/kg (p.o.). Bdph antagonized noradrenaline (NA) induced increases in blood pressure in anaesthetized normotensive rats. In addition, Bdph prevented the pituitrin‐induced T‐wave lowering of the ECG in anaesthetized rats. It also dose‐dependently decreased coronary arterial pressure in dogs. It is concluded that Bdph dilates coronary vessels. In vitro, Bdph non‐competitively antagonized adrenaline‐induced contraction in isolated rabbit aortic strips. It also significantly antagonized the NA‐induced maximum decrease in perfusion rate of isolated rabbit ears. However, the vasodilator effect may cause a heat loss because Bdph significantly lowered the rectal temperature of rats at ambient temperature of 20°C, but not at 30°C. Bdph might be a useful coronary dilator and antihypertensive drug.
Antifungal effects of α‐terthienyl from Tagetes patula on five dermatophytes
Authors: Romagnoli C. , Mares D. , Fasulo M. P. , Bruni A.
Published: October 2006

Alpha‐terthienyl (αT), a thiophene compound isolated from Tagetes patula (Asteraceae), exhibits antifungal activity towards five strains of dermatophytes (Trichophyton mentagrophytes, T. rubrum, T. violaceum, Epidermophyton floccosum, Microsporum cookei). αT plus UVA irradiation for 90 min acted as a fungistatic at concentrations between 6 μM and 24 μM. Between 1 and 10 days after irradiation, the fungal growth was reduced or arrested with marked responses for T. mentagrophytes, T. rubrum and M. cookei. The ultrastructural events that occur in Trichophyton mentagrophytes after treatment were studied by electron microscopy. In the dark, αT caused no important ultrastructural modifications within the hyphae. After UVA irradiation the photoactive compound caused damage to membranes of the nucleus, mitochondria and endoplasmic reticulum. Plasmolytic and autolytic changes resulted in plasma membrane breakage and in cell wall aberrations. UVA‐activated αT would appear to target protein‐rich membranes of the dermatophytes.
Hypolipedaemic activity of picroliv in albino rats
Authors: Khanna A. K. , Chander R. , Kapoor N. K. , Dhawan B. N.
Published: October 2006

The hypolipidaemic action of picroliv, a standarized preparaton from Picrorhiza kurrooa, has been studied in normal as well as in triton‐ and cholesterol‐fed rats. Serum lipids were found to be lowered by picroliv (25 mg/kg b.w.) in triton WR‐1339‐induced hyperlipaemia. Chronic feeding of this drug (6 mg/kg b.w.) in normal rats and in animals simultaneously treated with cholesterol (25 mg/kg b.w.) for 30 days caused lowering in the lipid and protein levels constituting β‐lipoproteins followed by an increase in high density lipoprotein cholesterol in experimental animals. Picroliv alters lipolytic activities in plasma, liver, heart an adipose tissues and stimulated receptor mediated catabolism of low density lipoprotein. The lipid lowering action of the natural product is mediated through inhibition of cholesterol biosynthesis in liver, increased faecal bile acid excretion and enhanced plasma lecithin: cholesterol acyltransferase activity.
Laminaria ochroleuca: A preliminary study of its effect on the central nervous system
Authors: Vázquez‐Freire M. J. , Lamela M. , Calleja J. M.
Published: October 2006

The effects were studied of a methanolic extract of the brown alga Laminaria ochroleuca on the central nervous system (CNS) of mice. Spontaneous motor activity, exploratory behaviour, motor coordination, d‐amphetamine‐induced hypermotility, body temperature, pentobarbital‐induced hypnosis, pentylenetetrazole‐induced convulsions and analgesic activity were assessed. At doses between 25 and 100mg/kg, the extract showed significant activity in all tests except that of pentylenetetrazole‐induced convulsions. It is concluded that the methanolic extract of Laminaria ochroleuca is a CNS depressant with slight analgesic activity.
A study on the action of a modified Wen‐Pi‐Tang prescription, using uraemic toxins in blood as indices
Authors: Yokozawa Takako , Miyauchi Isao , Oura Hikokichi , Zheng Ping Dong , Zhou Jia Jun
Published: October 2006

A modified Wen‐Pi‐Tang prescription (named Fu‐Zheng‐Jiang‐Zhuo‐Tang) containing Angelicae Radix, Paeonia Radix, Polygoni Radix, Pinellia Tuber and Zuo‐Jin‐Wan instead of Aconiti Tuber, Zingiberis Rhizoma and Glycyrrhizae Radix was given to rats with renal failure, and a decrease in the blood levels of uraemic toxins was observed. This effect closely resembled that of Wen‐Pi‐Tang, but these two prescriptions showed different effects when their Rhei Rhizoma contents were exchanged.
Participation of the serotonergic system in the memory effects of Ginkgo biloba L. and Panax ginseng C. A. Mey
Authors: Petkov V. D. , Belcheva S. , Konstantinova E. , Kehayov R. , Petkov V. V. , Hadjiivanova Chr.
Published: October 2006

The 7‐day oral administration of the extracts from Ginkgo biloba (GK501) and Panax ginseng (G115) as well as their combination PHL‐00701 (Gincosan®) produced changes in rat behaviour suggesting memory‐enhancing effects. Single doses of agonists and antagonists of different serotonin receptor subtypes influenced the rat's capability for retention of learned behaviour and the behavioural effects of the drugs tested. GK501 decreased the density (Bmax) of 5‐HT1 receptors in the frontal cerebral cortex and hippocampus. Data concerning the effects of the drugs tested suggest the participation of the serotonergic transmitter system as an important neurochemical correlate of rat behaviour and of the memory effects of the drugs studied. This participation is modulated by the differences in the functions of the serotonin receptor subtypes.
Oxytocic and oestrogenic effects of Monechma ciliatum methanol extract in vivo and in vitro in rodents
Authors: Uguru M. O. , Okwuasaba F. K. , Ekwenchi M. M. , Uguru V. E.
Published: October 2006

Various solvent extracts of the leaves of Monechma ciliatum (family Acanthecaea) were tested for oxytocic properties on uterine preparations in vivo and in vitro. The methanol extract (HME) contracted the nonpregnant uterus of the rat, guinea‐pig and mouse as well as preparations obtained from guinea‐pigs on days 6–7 and 11–12 of pregnancy. The rat pregnant uterus was not affected by the extract. Oral administration of HME to rats on days 15, 16 and 17 of pregnancy had no abortifacient effect compared with oxytocin. However, laparotomy on day 23 revealed fetal death in utero. The extract was also found to have oestrogenic activity based on parameters such as uterine weight ratio, premature vaginal opening and degree of vaginal cornification.
Cardiovascular effects of the aqueous extract of Moringa pterygosperma
Authors: Limaye Dnyanesh Arun , Nimbkar Anil Yashvant , Jain Rajeev , Ahmad Mansoor
Published: October 2006

The aqueous extract of stem bark of Moriga pterygosperma (Family Moraingaceae) was investigated for its effect on various pharmacological parameters. In cardiovascular profile at lower concentrations (1–10 ng) it produced a dose dependent positive inotropic effect (n = 3, 1.29 ± 0.021 for 10 ng) and at higher concentrations (0.1–1 μg) a dose dependent negative inotropic effect (n = 3, 0.53 ± 0.033 for 1 μg) on the isolated frog heart. It also produced a dose dependent hypotensive effect on dog blood pressure (n = 3, 82 ± 0.98 for 20 mg/kg). It failed to elicit any effect on isolated guinea‐pig ileum, rat stomach fundus or frog rectus abdominis muscle.
Shilajit attenuates streptozotocin induced diabetes mellitus and decrease in pancreatic islet superoxide dismutase activity in rats
Authors: Bhattacharya Salil K.
Published: October 2006

Diabetes mellitus was induced in male Wistar rats by the administration of streptozotocin (STZ, 45 mg/kg, s.c. on 2 consecutive days). Hyperglycaemia and superoxide dismutase activity of pancreatic islet cells was assessed on days 7, 14, 21 and 28, following STZ administration. In two other groups, shilajit (50 and 100 mg/kg, p.o.) was administered concurrently for 28 days. STZ induced significant hyperglycaemia by day 14, which increased progressively on days 21 and 28. STZ also induced a decrease in pancreatic islet cell superoxide dismutase, which was apparent by day 7 and increased progressively, thereafter on days 14, 21 and 28. Shilajit (50 and 100 mg/kg, p.o.) had no discernible per se effect on blood glucose levels in normal rats but attenuated the hyperglycaemic response of STZ from day 14 onwards, though only the effect of the higher dose was statistically significant. Similarly, both the doses of shilajit reduced the STZ‐induced decrease in superoxide dismutase activity from day 14 onwards, the effect of the lower dose being statistically insignificant. The findings confirm earlier observations that STZ‐induced hyperglycaemia may be the consequence of a decrease in pancreatic islet superoxide dismutase activity, leading to accumulation of free radicals and damage of the β‐cells. Shilajit attenuates both these effects of STZ possibly by its action as a free radical scavenger. The findings support the postulate that shilajit can prevent maturity onset diabetes mellitus.
Hypoglycaemic activity of selected European plants
Authors: Neef H. , Declercq P. , Laekeman G.
Published: October 2006

Nine European plants were selected to be screened for hypoglycaemic activity. Selection criteria were based on traditional use and literature references. Total extracts of the plants were prepared by boiling the dried material with water or macerating it with 80% ethanol. Male Swiss mice were orally loaded with glucose after the extracts had been given by oral gavage. Four extracts improved the glucose tolerance: Adiantum capillus veneris, Daucus carota, Galega officinalis and Juglans regia. Further investigation will be focused on bioguided isolation of active fractions.
Comparative study on the cytotoxic effect of viscotoxin and mistletoe lectin on tumour cells in culture
Authors: Urech K. , Schaller G. , Ziska P. , Giannattasio M.
Published: October 2006

A comparative study was carried out on the effect of viscotoxin and mistletoe lectin I, two mistletoe proteins known to be toxic to mammals, on three tumour cell lines in culture (Yoshida sarcoma cells, T‐cell leukaemia cells Molt4, and myeloid cells K562). Both viscotoxin and mistletoe lectin were cytotoxic for the three cell lines tested, although the cell sensitivity was dependent on the type of cells used. Yoshida cells were the most sensitive to viscotoxin (ED50= 0.7 μg/mL) and less sensitive to mistletoe lectin (ED50= 12.8 μg/mL). K562 cells were more sensitive to mistletoe lectin (ED50= 75 pg/mL) than Molt4 cells (ED50= 1.3 ng/mL), whose high sensitivity to mistletoe lectin is well known. Data are also reported showing that this cell line dependent sensitivity can be exploited to demonstrate and/or to discriminate the toxic activities of either substances in crude mistletoe extracts. In particular the Yoshida cell line can represent a suitable system for a bioassay of viscotoxin in these extracts.
Evaluation of the folklore use of Rhaptopetalum coriaceum olio as an abortifacient
Authors: Onu U. Oden
Published: October 2006

The antifertility effects of the methanol extract of Rhaptopetalum coriaceum stem bark were investigated in pregnant rats and oestrogen‐primed isolated rat uterus. Graded intraperitoneal doses (350, 700 and 1400 mg/kg) of the extract produced fetal discharges which were expressed as percent antifertility (16.6%, 50.0%, and 66.6% respectively). The extract induced an increase of spontaneous activity of oestrogen‐dominated rat uterus in a concentration‐related manner with an EC50 of 48.6 mg/mL.
Studies on the antiinflammatory and related pharmacological activities of Psidium guajava: A preliminary report
Authors: Sen T. , Nasralla Hussam S. H. , Chaudhuri A. K. Nag
Published: October 2006

The methanolic fraction of Psidium guajava fruit extract was found to possess significant inhibitory activity against carragenin, kaolin and turpentine‐induced oedema formation. The fraction significantly inhibited protein exudation. The proliferative form of inflammation was significantly counteracted following cotton pellet‐induced granuloma formation in rats. Acetic acid‐induced algesia (writhing) in mice was significantly inhibited by the fraction. Significant antipyretic activity of the fraction was observed following yeast‐induced pyrexia in rats. Potent antiarthritic activity was observed with the fraction against formaldehyde‐induced chronic arthritis in rats.
Antiinflammatory and vasoprotective activities of polysaccharides isolated from fruit bodies of higher Fungi P.1. polysaccharides from Trametes gibbosa (Pers.: Fr)Fr. (Polyporaceae)
Authors: Czarnecki Ryszard , Grzybek Jan
Published: October 2006

Polysaccharide fractions TG‐1 and TG‐2 were isolated from the fruit bodies of Trametes gibbosa (Pers.: Fr.) Fr.(Polyporaceae). Both fractions are glucans with trace amounts of other sugars. The polysaccharide fractions administered to rats intravenously, strongly inhibited vessel permeability in the rat pleural exudate model, induced by carragenan, but did not influence its density. Both polysaccharide fractions decreased considerably the total protein level in the pleural effusion. Fractions TG‐1 and TG‐2 antagonized effectively the inflammation mediator complex induced by carragenan and they neutralized the pharmacological effects with respect to small vessel permeability. At the same time they increased the number of neutrophils and eosinophils and decreased the number of lymphocytes in the peripheral blood. The pharmacological activity of polysaccharide fractions TG‐1 and TG‐2 confirms their function as potential factors responsible for the stabilization of a wall vessel, especially in pathological conditions leading to endothelial damage.
Analgesic and antipyretic effects of Ecballium elaterium (L.) A. Richard. Extract in rodents
Authors: Agil M. Ahmad , Risco S. , Miró M. , Navarro M. C. , Ocete M. A. , Jiménez J.
Published: October 2006

The dried (elaterium) or fresh juice from Ecballium elaterium fruit is used in the treatment of various inflammatory conditions in popular medicine. In this study the elaterium is examined for its analgesic and antipyretic effects in several animal models. The elaterium exhibits both analgesic and antipyretic activities.
Antihepatotoxic Effects of chlorogenic acid from Anthocephalus cadamba
Authors: Kapil A. , Koul I. B. , Suri O. P.
Published: October 2006

In the present study, chlorogenic acid (CGA) isolated from Anthocephalus cadamba was screened for hepatoprotective activity by in vitro and in vivo assay methods using carbon tetrachloride (CCl4) as a model of liver injury. Intraperitoneal administration of CGA to mice at a dose of 100 mg/kg body weight for 8 days caused significant reversal in lipid peroxidation, enzymatic leakage, cytochrome P450 (Cyt P450) inactivation and produced enhancement of cellular antioxidant defence in CCl4‐intoxicated mice, revealing that the antioxidative action of CGA is responsible for its liver protective activity. CGA exhibited a better therapeutic protective action than silymarin (SM), in CCl4‐administered mice.
Effect of Fabiana imbricata constituents on Rhopalosiphum padi and Heliothis zea
Authors: Schmeda/hirschmann G. , Román P. , Theoduloz C. , Donoso B. C. , Corcuera L. J.
Published: October 2006

The main secondary metabolites of Fabiana imbricata showed toxicity towards the greenbug Rhopalosiphum padi when administered in an artificial diet. A dose‐dependent toxicity was observed for fabiaimbricatan‐15‐oic acid and oleanolic acid at doses up to 3.0 mM (p <0.01). Both compounds apparently act as antifeedants at higher doses. Rutin also showed a dose‐related toxicity. Scopoletin and p‐hydroxyacetophenone were toxic at 6.0 mM. None of the compounds tested were toxic towards the fifth instar Heliothis zea larvae.
Effects of essential oils from certain Ziziphora species on swimming performance in mice
Authors: Öztürk Yusuf , Aydm Süleyman , Tecik Bahar , Başer K. Hüsnü Can
Published: October 2006

In Turkish folk medicine, Ziziphora species have been used as an infusion for various purposes such as for the sedative, stomachic, carminative, activities etc. Since some of the folkloric uses may be related to antistress (adaptogenic) activity or central nervous system depression, the effects of essential oils obtained from Z. tenuior, Z. taurica ssp. taurica and Z. taurica ssp. cleonioides on mice swimming performance were investigated. Acute lethal toxicities of these three Ziziphora oils were also studied. On the basis of our findings obtained, these essential oils from the Ziziphora species decreased the swimming time suggesting a central nervous system depressant activity.
Effects of leaf and root extracts of Nauclea latifolia on purinergic neurotransmission in the rat bladder
Authors: Udoh Francis V.
Published: October 2006

The leaf and root parts or their combination of Nauclea latifolia were separately extracted and their pharmacological effects on purinergic transmission in the bladder investigated. The leaf extract was very potent in potentiating purinergic neurotransmission by potentiating ATP induced contractions. These actions were more pronounced than the depression of potassium chloride evoked contraction of the bladder. The root extract depressed purinergic contraction of the bladder by a direct depressant action on the bladder smooth muscle since it did not modify ATP induced contractions. The leaf and root extracts antagonized each other when combined together. It is concluded that the leaf and root extracts of N. latifolia possess interesting pharmacological actions on the bladder.
Antiviral activity of Achyrocline flaccida Wein DC aqueous extract
Authors: Garcia G. , Cavallaro L. , Broussalis A. , Ferraro G. , Martino V. , De Torres R. , Coussio J. , Campos R.
Published: October 2006

Aqueous extracts (AE) of chyrocline flaccida exhibit true antiviral activity in vitro against different members of the Herpesvirus family (herpes simplex virus type 1 and 2, human cytomegalovirus, bovine herpesvirus and lower activity with pseudorabies virus). The extract had no activity against some RNA (naked and enveloped) viruses and adenoviruses. The extract was not virucidal but its antiviral index (AI) was sufficiently high to justify further analysis. A preliminary characterization indicates that an early step of viral replication was affected by the aqueous extract.
Biological screening of Italian medicinal plants for antibacterial activity
Authors: Izzo A. A. , di Carlo G. , Biscardi D. , de Fusco R. , Mascolo N. , Borrelli F. , Capasso F. , Fasulo M. P. , Autore G.
Published: October 2006

Some 68 plant extracts from 65 species belonging to 25 families were investigated for antibacterial activity against eight gram‐positive and gram‐negative bacteria. Of the 68 extracts, 64 (94.1%) exhibited inhibitory effects against one or more microorganisms. Furthermore, among the active extracts, 12 from 11 species exhibited a broad spectrum of activity. Discussion on the probable chemical components responsible for this activity is included.
Pharmacological evaluation of the dichloromethanol extract from Inula crithmoides L.
Authors: Barrachina M. D. , Bello R. , Esplugues J. , Sanz I. , Yúfera E. Primo
Published: October 2006

The pharmacological effect of the dichloromethanol extract of Inula crithmoides L. was analysed in in vitro and in vivo models. The extract dose‐dependently decreased arterial blood pressure and furthermore it showed low acute toxicity, CNS depressor activity and analgesic and antiinflammatory effects. Preincubation of the guineapig ileum and rat duodenum (100 μg/mL) produced a significant reduction in the contractile effects of histamine and acetylcholine and a concentration‐related inhibition of the effects of serotonin. Following further fractionation the methylene chloride/acetone (50/50) fraction caused a significant decrease in motor activity and significantly reduced the threshold of pain chemical stimulus.
Antibacterial activity of diosquinone and plumbagin from the root of Diospyros mespiliformis (Hostch) (Ebenaceae)
Authors: Lajubutu B. A. , Pinney R. J. , Roberts M. F. , Odelola H. A. , Oso B. A.
Published: October 2006

Diosquinone and plumbagin isolated from the root of Diospyros mespiliformis (Hostch), a common Ingredient in several folk medicines and foods, have been shown to have antibacterial activity against a wide range of organisms. The minimum inhibitory concentrations (MICs) of diosquinone against Staphylococcus aureus NCTC 6571 and S. aureus E3T ranged from 3 to 30 μg/mL, while those against Escherichia coli KL16 and Pseudomonas aeruginosa NCTC 6750 ranged from 15 to 16 μg/mL. MICs were found to increase with the concentration of cells used in the inoculum. Bacterial studies showed that S. aureus NCTC 6571 exhibited a paradoxical biphasic response to dioquinone in nutrient broth, whereas bacterial activity against E. coli KL16 increased with concentration up to the highest concentration of dioquinone tested. Activity against E. coli KL16 was more pronounced in phosphate‐buffered saline than in nutrient broth.
The immunomodulatory effect of saikosaponin derivatives and the root extract of Bupleurum kaoi in mice
Authors: Yen Ming‐Hong , Lin Chun‐Ching , Yen Chuan‐Min
Published: October 2006

The saikosaponins ‐a(SSa), ‐d(SSd), ‐f(SSf), crude saponin mixture (CSM) and H2O‐layer components (HLC) which were isolated from the root of Bupleurum kaoi Liu, Chao et Chuang (Umbelliferae), demonstrated an immunomodulatory effect. Mice of the BALB/c strain were injected peritoneally with drugs to assess immune responses weekly over a 4 week period. The results showed that the mean ratio of thymus weight to body weight increased during week 1 but declined gradually thereafter; the ratio of helper T‐cells to suppressor T‐cells (Th/Ts) from mice treated with SSf and HLC gradually increased; however, in mice treated with SSa, SSd and CSM, the ratio rose to a maximum at week 3 and then decreased; the IL‐2 level of treated mice was significantly higher than that of the control group throughout the test period; the ratio of spleen weight to body weight in all drug treated groups increased weekly; the activity of B‐cell stimulation in mice was promoted week by week; levels of IgA, IgG and IgM in serum of SSd and SSa treated animals increased. An in vitro study, involving stimulation of IL‐1 demonstrated the following order of potency: SSd<SSa, 23‐O‐AcSSa and CSM<SSf and HLC.
In vitro and in vivo antimalarial activity of cryptolepine, a plant‐derived indoloquinoline
Authors: Kirby G. C. , Paine A. , Warhurst D. C. , Noamese B. K. , Phillipson J. D.
Published: October 2006

Cryptolepine is an indoloquinoline, high yields of which may be extracted from the roots of the West African shrub Cryptolepis sanguinolenta. The use of this plant as a traditional treatment for malaria is widespread in Ghana and is reported to be clinically effective. We have tested cryptolepine for in vitro antiplasmodial activity against the multidrug resistant (K1) strain of Plasmodium falciparum and found it to be highly active with an IC50 value of 0.031±0.0085 (SE) μg/mL, equivalent to 0.134±0.037 μM (n = 3). In a 4‐day suppression test there was, however, no significant reduction in parasitaemia in P. berghei‐infected mice treated subcutaneously with cryptolepine (7–113 mg/kg/d×4), when compared with untreated controls. Like 9‐aminoacridine, this compound appears to intercalate with DNA and this may explain the high degree of antimalarial activity demonstrated in vitro.
Antiinflammatory activity and effects on isolated smooth muscle of extracts from different Teucrium species
Authors: Barrachina M. D. , Bello R. , Martínez‐Cuesta M. A. , Esplugues J. , Primo‐Yúfera E.
Published: October 2006

The present study analyses the antiinflammatory effects and the action on in vitro motility of methanol and dichloromethanol extracts and stems of four Teucrium species (T. flavum, T. cartaginenses, T. buxifolium and T. pumillum). The antiinflammatory activity was tested in the carrageenan‐induced paw oedema in rats. T. flavum methanol (200 mg/kg, i.p.) and dichloromethanol (138 mg/kg, i.p.) extracts showed a significant anti‐inflammatory effect through the 24 h experimental period and reduced the Emax induced by histamine and serotonin in vitro on guinea‐pig ileum and rat uterus respectively. These extracts did not modify the contractile effects induced by acetylcholine on rat duodenum and noradrenaline on rat vas deferens. The methanol extracts of T. pumillum (50 mg/kg, i.p.) and T. buxifolium (26 mg/kg, i.p.) exhibited significant antiinflammatory effects only in the acute phase of the oedema (2 h) without affecting the chronic phase (24 h). In guinea‐pig ileum, rat uterus and rat vas deferens, the methanol extract of T. pumillum reduced the maximal effect induced by histamine, serotonin and noradrenaline, respectively, whereas the methanol extract of T. buxifolium lacked any effect on the contractile activity induced by various agonists in vitro. When tested for antiinflammatory activity the methanol (200 mg/kg, i.p.) and dichloromethanol (200 mg/kg, i.p.) extracts of T. cartaginenses did not modify the oedematous response induced by carrageenan administration.
Effects of flavonoids on cytochrome P‐450 from rat liver microsomes: Inhibition of enzyme activities and protection against peroxidative damage
Authors: Ubeda A. , Esteve M. L. , Alcaraz M. J. , Cheeseman K. H. , Slater T. F.
Published: October 2006

A series of flavonoids, able to inhibit non‐enzymic and enzymic lipid peroxidation, were investigated as inhibitors of cytochrome P‐450 mediated reactions (aminopyrine N‐demethylation and aniline hydroxylation) in rat liver microsomes. The most potent compounds were chrysin, luteolin, amentoflavone and eriodictyol (aminopyrine N‐demethylation) and apigenin, kaempferol and quercetin (aniline hydroxylation). Some structure‐activity relationships were established for inhibition of aminopyrine N‐demethylation and it was observed that the resorcinol configuration of the ring A is a determinant feature, whereas O‐glycosylation abolished the activity. Most of the compounds showed lower activity on aniline hydroxylation. The presence of these flavonoids during incubation of microsomes in a medium containing NADPH did not modify the cytochrome P‐450 concentration and protected against lipid peroxidation induced degradation of this cytochrome.
Investigation of korean plant extracts for potential phytotherapeutic agents against B‐virus hepatitis
Authors: Chung T. H. , Kim J. C. , Kim M. K. , Choi S. C. , Kim S. L. , Chung J. M. , Lee I. S. , Kim S. H. , Hahn K. S. , Lee I. P.
Published: October 2006

The present study was undertaken to identify potential phytotherapeutic agents among the aqueous extracts of 151 herbal medicinal plants of Korea. Extracts were assayed for (1) binding potency to hepatitis B‐virus surface antigen (HBsAg), and (2) inhibition of serum hepatitis B‐virus DNA polymerase activity. Of the 151 aqueous plant extracts tested, 33 demonstrated a positive precipitation reaction with HBsAg+ serum, and 15 of these specifically bound HBsAg in serum as well as recombinant HBsAg (Hepavax®). Nine extracts competitively inhibited >80% of anti‐HBsAg antibody binding to Hepavax® HBsAg. Furthermore, nine of these 15 plant extracts also exhibited greater than 25%—50% inhibition of hepatitis B‐virus (HBV) DNA polymerase activity, and also significantly stimulated production of the potent cytokine, tumour necrosis factor (TNF). None of the extract concentrations used altered liver function parameters of normal rats.
Wound healing effects ofAloegel and other topical antibacterial agents on rat skin
Authors: Heggers John P. , Kucukcelebi Ahmet , Stabenau Catherine J. , Ko Francis , Broemeling Lyle D. , Robson Martin C. , Winters Wendell D.
Published: October 2006

The effects of topical antibacterials were studied in an acute wound healing model. Sprague‐Dawley rats after appropriate anaesthesia received four 1.5 cm2dorsal defects through the skin and panniculus carnosus. Skin defects were treated for 14 days with 2% mupirocin ointment, 1% clindamycin cream, 1% silver sulfadiazine cream +Aloe veragel, and silver sulfadiazine combined withAloegel. An untreated group served as controls. Each group was comprised of 10 animals each to achieve statistical significance. Wound closure rate was assessed by serial planimetry. Following healing, the breaking strength of each resultant scar was determined. Wound half‐lives and overall healing rates were calculated by regressing the log of the areas of all wounds over time. Overall healing rates of all the treated groups were significantly different compared with control group (p<0.05). TheAloegroup had the shortest half‐life and healed faster than the control group. All the other treated groups had no longer half‐lives when compared with the control group. While silver sulfadiazine +Aloeincreased the breaking strength of the healed wound,Aloealone did not, but demonstrated an increase over the control. TopicalAloesignificantly enhances the rate of wound healing and when combined with silver sulfadiazine reverses the wound retardant effect observed with silver sulfadiazine. Clindamycin and mupirocin significantly delay wound closure. However mupirocin enhanced the breaking strength of the wound.
Effects of antiinflammatory plant extracts on ovoimplantation in rats
Authors: Rao V. S. N. , Silva J. C. R. , Medeiros F. C.
Published: October 2006

The effects of five antiinflammatory plant extracts on ovoimplantation was investigated in albino rats. Rats treated with plant extracts from days 4 to 6 (periimplantation) of pregnancy showed either a total absence (20%–40%) or a considerably reduced number of implantations in utero. The observation suggests that the use of antiinflammatory plant extracts during the periimplantation period impairs fertility probably by reducing the vascular permeability which is an obligate accompaniment of normal implantation.
Hypoglycaemic activity of Nelumbo nucifera gaertn. (Fam. Nymphaeaceae) rhizome (methanolic extract) in streptozotocin‐induced diabetic rats
Authors: Mukherjee Pulok Kumar , Pal Saroj K. , Saha Kakali , Saha B. P.
Published: October 2006

The hypoglycaemic effect of the rhizome extract of Nelumbo nucifera was studied in streptozotocin‐induced diabetic rats. A methanol extract of the plant obtained by soxhlet extraction from finely pulverized rhizomes was used. The LD50 of the extract was found to be 2 g/kg. The extract (300 mg/kg and 600 mg/kg, orally) caused a reduction of blood glucose levels in streptozotocin‐induced diabetic rats by 53% (p<0.001) and 55% (p<0.001) respectively at the end of 12 h. The results of this study indicate that the methanol extract of the rhizome possesses favourable hypoglycaemic activity in hyperglycaemic animals taking chlorpropamide as a standard.
Castanospermine, an HIV inhibitor from tissue cultures of Castanospermum australe
Authors: Roja G. , Heble M. R.
Published: October 2006

Tree species are important sources of phytotherapeutics. The seeds of the tree Castanospermum australe contain alkaloids effective against HIV. Unorganized callus cultures were established from the leaves of the mature tree on a chemically defined nutrient medium of Murashige and Skoog supplemented with 2,4‐dichlorophenoxyacetic acid and benzyladenine. The alkaloids were separated and identified by gas liquid chromatographic analysis. The cultures synthesized castanospermine (0.004% F.W.) indicating that the biosynthetic ability of the highly differentiated seeds of the tree is expressed in the unorganized cells.
Effects of Sclerocarya birroea Hochst. extract on some metabolic activities in the rat
Authors: Trovato A. , Kirjavainen S. , Galati E. M. , Forestieri A. M. , Iauk L.
Published: October 2006

The decoction of Sclerocarya birroea Hochst. shows hypoglycaemic effects, an increase in plasma IRI in normal rats and an incremented oral‐glucose tolerance. The decoction is also active against diet‐induced hypercholesterolaemia.
Catechols and quercetin reduce MTT through iron ions: A possible artefact in cell viability assays
Authors: Habtemariam Solomon
Published: October 2006

The reduction of MTT (d‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) by mitochondrial enzymes to its blue formazan product is a widely used colorimetric assay method to determine the viability of cells in culture. In the present study the reduction of MTT by several agents in the absence of living cells was investigated. Several catechols and the flavonoid quercetin were found to reduce MTT in serum‐supplemented Dulbecco's modified Eagle's medium. All the agents tested failed to reduce MTT in Hank's balanced salt solution, but supplementing this buffer with serum or iron ions resulted in MTT reduction. The involvement of an iron‐catalysed redox reaction in the reduction of MTT induced by catechols and flavonoids was demonstrated. Caution is needed in using MTT in cell viability assays involving such chemicals.
Free Wilson Analysis. Theory, Applications and its Relationship to Hansch Analysis
Authors: Kubinyi Hugo
Published: October 2006

The Free Wilson model is a simple and efficient method for the quantitative description of structure activity relationships. It is the only numerical method which directly relates structural features with biological properties, in contrast to Hansch analysis, where physicochemical properties are correlated with biological activity values. Nevertheless both approaches are closely interrelated, not only from a theoretical point of view, but also in their practical applicability. In many cases both models can be combined to a mixed approach which includes Free Wilson type parameters to describe the activity contributions of certain structural modifications and physicochemical parameters to describe the effect of some other substituents on the biological activity. Many successful applications, especially from the work of Hansch and his group on the structure activity relationships of enzyme inhibitors, demonstrate that this combined model is the most powerful tool of classical QSAR.
Qualitative and Quantitative Structure‐Activity Relationships for Calcium Channel Modulating 1,4‐Dihydropyridine Derivatives: A Hypothetical Molecular Receptor Model
Authors: Höltje Hans‐Dieter , Marrer Stephan
Published: October 2006

Based on force field methods, quantum chemical calculations and using molecular graphics a hypothetical receptor model for calcium antagonists and agonists from the 1,4‐dihydropyridine (DHP) series has been developed. In a previous study it could be shown, that calcium channel activating DHP's reduced the molecular electrostatic receptor potential, while this is increased by calcium channel blocking DHP's. These effects offer a possible explanation for the opposite behaviour of chiral dihydropyridines. In continuation of this work a quantitative structure‐activity study with a group of calcium channel blockers provided a three binding site model for the drug receptor interaction. Calculated interaction energies correlate well with biological potencies (r = 0.94, s = 0.28). The postulated receptor model shows structural similarities to segments of the very recently published amino acid sequence of the receptor for 1,4‐dihydropyridine calcium channel blockers.
The Effect of Molecular Structure on the Distribution and Elimination of Some Organic Acids in Rats
Authors: Lázniček Milan , Kvêtina Jaroslav
Published: October 2006

The pharmacokinetics and distribution of nine model acidic drugs (iodobenzoic, iodophenylacetic and iodohippuric acid derivatives) in rats were investigated following intravenous injection. The distribution volume of the central compartment increases linearly with increasing free drug fraction in plasma. Relatively weaker correlations were found between the distribution volume at steady‐state and lipophilicity or plasma protein binding. Even when a statistically relevant correlation between total plasma clearance and lipophilicity was found, this relation expresses rather the difference between individual acids. Comparing the individual position isomers, substitution of the aromatic ring with iodine in the para position leads to a strong decrease in the total plasma clearance value in contrast to a change in their lipophilicity. It shows that the total plasma clearance value is dependent not only on the lipophilicity, but on the geometry of drugs under study as well.
Viscosimetric Evaluation of Solvent Effects. II. Determination of the Range of the Applicability of the Method
Authors: Batko Anna , Mazurkiewicz Józef , Tomasik Piotr
Published: October 2006

The intrinsic viscosities of solutions of a naphthalene derivative series i.e. quinoline, isoquinoline, 2‐methoxynaphthalene, 2‐naphthyl acetate, 1‐nitronaphthalene, 1‐naphthol and 2‐naphthol were determined in a series of aromatic solvents like benzene, toluene, anisole, pyridine, chlorobenzene and nitrobenzene. These magnitudes were correlated with various parameters which characterize solvents and solvent – solute interactions, the Lewis acidity and basicity, the Kirkwood function, the dipol moment, the molar polarizability, the function of polarizability as well as the Večeřa parameters. The polar solvation seems to be the predominating component of the solvent – solute effect in the case of quinoline, isoquinoline, 2‐methoxynaphthalene and 2‐naphthyl acetate whereas other factors become more important in case of the remaining compounds studied. The viscosimetric method appears to be suitable for the quantitative study of the solvent effect even if mainly Van der Waals forces are involved in the solvent – solute interactions and molecular weight of solute reaches hardly about 130 a.m.u.
Principal Properties for Aromatic Substituents. A Multivariate Approach for Design in QSAR
Authors: Skagerberg Bert , Bonelli Daniela , Clementi Sergio , Cruciani Gabriele , Ebert Cynthia
Published: October 2006

A set of a hundred aromatic substituents were multivariately characterized by nine descriptor variables taken from the literature. From the 9*100 data set were calculated four principal properties for the aromatic substituents as the four first dimensions in a principal components analysis, PCA. The first three principal properties were used to develop a strategy for selecting substituents from eight subgroups according to a factorial design.
Theoretical Approximation to the Reaction Mechanism of Adenosine Deaminase
Authors: Orozco Modesto , Lluis Carmen , Mallol Josefa , Canela Enric I. , Franco Rafael
Published: October 2006

A quantum chemistry‐based strategy has been used for obtaining correlations between electronic parameters and the relative activity of some adenosine analogues that are substrates of adenosine deaminase. A semi‐empirical method (MOPAC program using AM1 hamiltonian) has been used for designing a molecule, alternative to adenosine, and less expensive from a computational point of view. It has been demonstrated that 9‐hydroxymethyl‐adenine effectively mimics adenosine behaviour in terms of electronic characteristics of purine ring. The parameters studied were net charge on N1 and C6, global (∑Q) charge over pyrimidine and purine rings and orbital frontier parameters over C6 and N1. For analogues of adenosine and formycin in which ribose were substituted by a hydroxymethyl group, correlations between these parameters and the log Vm of reaction (collected from experimental data) with adenosine deaminase have been studied. The results indicate that there is an increase in the maximum rate of deamination Vm when the negative net charge over the pyrimidine and purine rings also increases. In view of the results obtained with different forms (neutral, protonated at N1 and hydroxylated at C6) of adenosine and formycin analogues it is suggested that the protonation at N1 is the rate limiting step of the reaction catalyzed by adenosine deaminase.
Conformational Analysis on Calcium Channel Active Diphenylalkylamines, Diphenylbutylpiperidines, Phenylalkylamines, and Perhexiline
Authors: Höltje Hans‐Dieter , Maurhofer Ernst
Published: October 2006

A conformational analysis on calcium antagonists with diphenylalkylamine and diphenylbutylamine structure was performed based on force field calculations. Superposition of all energetically permitted conformations of all compounds under study led to the development of a common pharmacophore for both diphenylalkylamines (DPAAs) and diphenylbutylpiperidines (DPBPs). The pharmacophore consists of a – under physiological conditions protonated – nitrogen atom and three aromatic substructures. Conformational calculations on the verapamil derivative S( — )‐D595 and perhexiline showed that both substances possibly also interact with the DPAA/DPBP‐receptor.