Phytochemical Analysis, Antispasmodic, Myorelaxant, and Antioxidant Effect of Dysphania ambrosioides (L.) Mosyakin and Clemants Flower Hydroethanolic Extracts and Its Chloroform and Ethyl Acetate Fractions.

Dysphania ambrosioides (L.) Mosyakin and Clemants is an annual or ephemeral perennial herb used traditionally in the Mediterranean region in folk medicine to treat various illnesses, including those related to the digestive system. This study aims to assess the antispasmodic, myorelaxant, and antioxidant effects of D. ambrosioides flower hydroethanolic extract and its chloroform and ethyl acetate fractions in a comparative study to evaluate the result of the extraction type on the potential activity of the extract. Both rat and rabbit jejunum were used to evaluate the antispasmodic and myorelaxant effect, while the antioxidant effect was evaluated using DPPH, a ferric reducing power assay, and a beta-carotene bleaching test. LC/MS-MS analysis was carried out to reveal the composition of the different types of extract. Following the results, the hydroethanolic extract showed a significant myorelaxant effect (IC50 = 0.39 ± 0.01 mg/mL). Moreover, it was shown that the hydroethanolic extract demonstrated the best antispasmodic activity (IC50 = 0.51 ± 0.05 mg/mL), followed by the ethyl acetate (IC50 = 4.05 ± 0.32 mg/mL) and chloroform (IC50 = 4.34 ± 0.45 mg/mL) fractions. The antioxidant tests showed that the hydroethanolic extract demonstrated high antioxidant activity, followed by the ethyl acetate and chloroform fractions. The LC/MS-MS analysis indicates that the plant extract was rich in flavonoids, to which the extract activity has been attributed. This study supports the traditional use of this plant to treat digestive problems, especially those with spasms.

Spasmogenic and spasmolytic activities of Agastache mexicana ssp. mexicana and A. mexicana ssp. xolocotziana methanolic extracts on the guinea pig ileum.

ETHNOPHARMACOLOGICAL RELEVANCE: Agastache mexicana has been used in traditional medicine for relief of abdominal pain and treatment of other diseases. Two subspecies have been identified: A. mexicana ssp. mexicana (AMM) and A. mexicana ssp. xolocotziana (AMX) and both are used traditionally without distinction or in combination. AIM OF THE STUDY: To determine the effect of methanol extracts of A. mexicana ssp. mexicana and A. mexicana ssp. xolocotziana on gut motility and their possible mechanism of action. MATERIALS AND METHODS: The effect of AMM and AMX methanol extracts were tested on the spontaneous activity in the isolated guinea pig ileum and on tissues pre-contracted with KCl, electrical field stimulation (EFS) or ACh. In addition, the possible mechanism of action of each subspecies on gut motility was analyzed in the presence of hexametonium, indomethacin, L-NAME, verapamil, atropine or pyrylamine. A comparative chromatographic profile of these extracts was also done to indicate the most abundant flavonoids presents in methanol extracts of both subspecies. RESULTS: AMM, but not AMX, induced a contractile effect in the guinea pig ileum. This spasmogenic effect was partially inhibited by atropine, antagonist of muscarinic receptors; and pyrilamine, antagonist of H1 receptors. In contrast, AMX, but not AMM, diminished the contractions induced by KCl, EFS or ACh. The spasmolytic activity of AMX was partially inhibited by hexamethonium, ganglionic blocker; and indomethacin, inhibitor of the synthesis of prostaglandins; but not by L-NAME, inhibitor of nitric oxide synthase. In addition, AMX diminished the maximal contraction induced by CaCl2 in a calcium-free medium. Chromatographic analyses of these methanol extracts showed the presence of acacetin and tilanin in both. CONCLUSIONS: These results suggest that in folk medicine only AMX should be used as spasmolytic, and not in combination with AMM as traditionally occurs, due to the spasmogenic effects of the latter. In addition, activation of nicotinic receptors, prostaglandins and calcium channels, but not nitric oxide mechanisms, could be responsible for the spasmolytic activity of AMX. On the other hand, release of ACh and histamine could be involved in the spasmogenic effect induced by AMM. Acacetin and tilanin are present in methanol extracts of both subspecies and both flavonoids were more abundant in AMX than AMM. Our findings contribute to the validation of the traditional use of Agastache mexicana in relieving gastrointestinal disorders, but indicate that the subspecie that should be used for this effect is A. mexicana ssp. xolocotziana.

The medical plant butterbur (Petasites): analytical and physiological (re)view.

Butterbur (Petasites) is an ancient plant which has been used for medical and edible purposes with its spasmolytic agents. However, toxic alkaloid content of the plant limits its direct usage. The paper covers the pyrrolizidine alkaloids (PAs) and butterbur themes in detail in order to display the outline of alkaloid-free plant extract production for medical and edible purposes. The toxic PAs and medicinal constituents of the plant are described with emphasis on analytics, physiological effects and published patent data on alkaloid free extract production. The analytics is based on several commonly used analytical methods including liquid chromatography-mass spectrometry, gas chromatography-mass spectrometry and enzyme linked immunoassay analysis of PAs and N-oxides based on published literature data of butterbur. The analyses of major medicinal constituents of butterbur are given and the physiological effects of these compounds have been discussed to attract attention to the importance of alkaloid-free extract production. The concentration distributions of the medicinal constituents and toxic PAs in different parts of the plant and the outcomes of the published patent data provide comprehensive information for proper plant raw-material selection and production of alkaloid-free butterbur extracts. The review is intended to guide researchers interested in medical plant extracts by providing comprehensive data on the medical plant butterbur and its chemical constituents.

Quantitatively analyze composition principle of Ma Huang Tang by structural equation modeling.

ETHNOPHARMACOLOGICAL RELEVANCE: In Chinese classic formulas, Ma Huang Tang (MHT), composed of Ephedra, Cassia twig, Bitter apricot kernel and Prepared licorice, has been widely used to treat cold, influenza, acute bronchitis, bronchial asthma and other pulmonary diseases. However, there is no quantitative interpretation about composition principle of MHT as well as other Chinese compound prescriptions. This study was aimed using structural equation modeling (SEM) to decipher 'monarch, minister, assistant and guide' which is the unique and integrated composition principle of Chinese compound recipes, by taking MHT for instance. MATERIALS AND METHODS: Sixteen prescriptions of different dose ratios were combined orthogonally from four herbal drugs of MHT, then their diaphoretic, antispasmodic and analgesic effects were assessed by the indicators of the rat sweating point number, the spasmolysis percentage of guinea pig trachea and the murine writhing number, respectively. Basing on SME, the systematology analysis method to complex causality, path diagrams for herbal drugs were drawn with the Amos software and the relationships of the four herbal ingredients and therapeutic effects were measured. RESULTS: Sixteen recipes induced SD rats sweating, remitted spasm of guinea pig trachea smooth muscle, and relieved ICR mouse pain due to acetic acid in comparison with animal model group or normal control groups. Three different SME models were specified and the relevant relationship was analyzed. According to the results of measured standardized path coefficients, Ephedra exerts the greatest contribution to the integral potency, so it acts as the monarch drug in MHT; Cassia twig is slightly weakly effective than Ephedra, and has the most significant interaction with Ephedra, which shows that it is the minister drug; the direct effects of Bitter apricot kernel and Prepared licorice on the integral potency are non-significant, while these two drugs have very significant synergetic effect with Ephedra or Cassia twig, thus they can be interpreted as subordinate drugs to strengthen the therapeutical effects of the monarch and minister drugs; the higher interaction values of Bitter apricot kernel suggest that it is the assistant drug, and Prepared licorice is the guide drug with lower values. CONCLUSION: SME can be used to quantitatively analyze the composition principle of Chinese compound prescriptions like MHT, which demystifies the ancient and classical system theory of traditional Chinese medicine from a totally new viewpoint.

Bioassay-guided fractionation of a thymol-deprived hydrophilic thyme extract and its antispasmodic effect.

ETHNOPHARMACOLOGICAL RELEVANCE: Extracts from Thymus vulgaris L. and Thymus zygis L. are traditionally used for bronchitis, catarrhs of the respiratory tract and supportive treatment of pertussis. A potential spasmolytic effect is thought to be due to the presence of the monoterpenoid phenols thymol and carvacrol in the extract. Based on previous data the present investigation aimed to clarify if thymol-deprived thyme extracts (as been in use within German drug market) have antispasmodic activity. Additionally compounds responsible for this effect had to be identified. MATERIALS AND METHODS: Thyme fluid extract was subsequently fractionated by FCPC, LPLC, and HPLC and compounds isolated were identified by spectroscopic methods. Bioassay testing was done by quantification of antispasmodic activity in the preconstricted rat smooth muscle trachea model against papaverin as positive control. RESULTS: Thymol-deprived spissum extract (SE) had good antispasmodic activity (-37%, related to the maximum contraction). Bioassay-guided fractionation indicated that rosmarinic acid and apigenin do not contribute to this effect. Luteolin contributed significantly to the antispasmodic activity (-9%). CONCLUSIONS: Thyme extracts have antispasmodic activity, which is at least due to synergistic effects of phenolic volatile oil compounds and the flavone luteolin. Specifications of thyme-containing preparations should refer to this flavone in addition to focusing on the volatile phenols.

Volatile composition and biological activity of key lime Citrus aurantifolia essential oil.

The essential oil of Citrus aurantifolia (Christm) Swingle fruits (limes) was studied for its potential spasmolytic effects in relation to its chemical composition. The essential oil, extracted by hydrodistillation (HD), was analyzed by GC-FID and GC-MS. The antispasmodic activity was evaluated on isolated rabbit jejunum, aorta and uterus. The results indicated that the essential oil of C. aurantifolia possesses important spasmolytic properties, which are likely to be due to its major constituents, limonene (58.4%), beta-pinene (15.4%), gamma-terpinene (8.5%), and citral (4.4%).

Gut modulatory effects of Daphne oleoides are mediated through cholinergic and Ca++ antagonist mechanisms.

CONTEXT: The present study describes the spasmogenic and spasmolytic activities of Daphne oleoides Schreb. (Thymelaeaceae), exploring the possible underlying pharmacological mechanisms. AIM: Pharmacological investigation of Daphne oleoides to provide evidence for its therapeutic application in gastrointestinal motility disorders. MATERIALS AND METHODS: Methanol crude extract of Daphne oleoides (Do.Cr) was studied in gastrointestinal isolated tissues. RESULTS: In spontaneously contracting rabbit jejunum preparations, Do.Cr at 0.3-3.0 mg/mL caused moderate stimulation, followed by relaxant effect at the next higher concentrations (5.0-10 mg/mL). In presence of atropine, spasmogenic effect was blocked and the relaxation was emerged, suggesting that the spasmogenic effect of Daphne oleoides is mediated through activation of muscarinic receptors. When tested against the high K+ (80 mM)-induced contractions, Do.Cr (0.3-5.0 mg/mL), like verapamil, inhibited the induced contractions, suggesting Ca++ channel blockade (CCB) effect. The CCB effect was further confirmed when pre-treatment of the tissue with Do.Cr shifted the Ca++ concentration-response curves to the right, similar to that caused by verapamil. DISCUSSION AND CONCLUSION: These results indicate that Daphne oleoides exhibits gut excitatory and inhibitory effects, occurred via cholinergic and Ca++ antagonistic pathways, respectively.

Antidiarrhoea and toxicological evaluation of the leaf extract of Dissotis rotundifolia Triana (Melastomataceae).

BACKGROUND: The leaves of Dissotis rotundifolia are used ethnomedically across Africa without scientific basis or safety concerns. Determination of its phytochemical constituents, antimicrobial activity, effects on the gastrointestinal tract (GIT) as well as toxicological profile will provide supportive scientific evidence in favour of its continous usage. METHOD: Chemical and chromatographic tests were employed in phytochemical investigations. Inhibitory activity against clinical strains of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Salmonella typhi were compared with Gentamycin. Our report includes minimum inhibitory concentration (MIC) against the tested organisms. The effect of the ethanol extract on the motility of the GIT in mice using the charcoal plug method and castor oil induced diarrhoea in rats was evaluated. Toxicological evaluation was determined by administering 250 mg/kg and 500 mg/kg of extracts on male Wistar rats for 14 days with normal saline as control. The tissues of the kidneys, liver, heart and testes were examined. RESULTS: Phytochemical studies revealed the presence of alkaloids, saponin and cardiac glycosides. The crude ethanol extract and fractions inhibited the growth of E. coli, P. aeruginosa, S. aureus and S. typhi to varying extents. The degree of transition exhibited by the charcoal meal was dose-dependent. In the castor oil induced diarrhoea test, all the doses showed anti-spasmodic effects. The LD50 in mice was above 500 mg/kg body weight. Toxicological evaluation at 500 mg/kg showed increased cytoplasmic eosinophilia and densely stained nuclei of the liver, tubular necrosis of the kidney, presence of ill-defined testes with indistinct cell outlines and no remarkable changes in the heart. CONCLUSION: Ethanol extracts of Dissotis rotundifolia have demonstrated antimicrobial activity against clinical strains of selected microorganisms. The plant showed potential for application in the treatment of diarrhoea, thereby justifying its usage across Africa. It also demonstrated toxicity in certain organs at the dose of 500 mg/kg, and it will be necessary to fully establish its safety profile.

Inhibitory effects of active fraction and its main components of Shaofu Zhuyu decoction on uterus contraction.

Shaofu Zhuyu decoction is a famous formula for treating primary dysmenorrhea in China since the Qing dynasty. In this paper, the inhibitory effects of active-guided fraction and its main bioactive components of Shaofu Zhuyu decoction on a model of non-pregnant mice uterine contraction induced by oxytocin in vitro were investigated. Qualitative and quantitative chemical analyses were used to correlate the chemical composition of active fraction with the spasmolytic effects. Seven ingredients in the active fraction were identified and quantified by HPLC-DAD. Three ingredients, ferulic acid, vanillic acid, and typhaneoside, were evaluated for their effects on mice isolated uterine contraction induced by oxytocin in vitro. The ED(50) of them were 63.0 microg/ml, 57.6 microg/ml, 109.7 microg/ml, respectively. Furthermore, the inhibitory activity of the combination of these three compounds was prior to the fraction and seven compounds group. The ED(50) was 65.5 microg/ml. The data stated that ferulic acid, vanillic acid, and typhaneoside were possibly the main active components in the bioactive fraction of Shaofu Zhuyu decoction. The study also implied that Shaofu Zhuyu decoction may have direct inhibitory effects on the contractility of the mice uterus and justified the traditional use of the prescription for treating the uterine cramping associated dysmenorrhea.

In vitro antimicrobial, antioxidant, and antispasmodic activities and the composition of the essential oil of Origanum acutidens (Hand.-Mazz.) Ietswaart.

The radical scavenging, antimicrobial, and antispasmodic activities and the composition of Origanum acutidens (Hand.-Mazz.) Ietswaart (Order Labiatte) essential oil were evaluated in vitro. Gas chromatography/mass spectrometry analysis of the oil resulted in the identification of 20 compounds, representing 93.61% of the oil; carvacrol (65%) was the main component. The sample was also subjected to a screening for antioxidant activity by using the 1,1-diphenyl-2-picrylhydrazyl and beta-carotene/linoleic acid assays. The essential oil exhibited strong antioxidant activity. Using the agar disk diffusion method, antimicrobial activities of the essential oils were determined for nine microorganisms; antimicrobial activity was shown against eight of them. O. acutidens oil exhibited spontaneous contractions in rat ileum at the 100% level at 0.1 mg/mL level.

Effect of essential oil of Anthemis mauritiana Maire & Sennen flowers on intestinal smooth muscle contractility.

The aim of the present study is to determine the chemical composition of the essential oil extracted from the flowers of Anthemis mauritiana Maire & Sennen (EOAM) and to investigate its antispasmodic effects on intestinal smooth muscle. The phytochemical composition was revealed by gas chromatography-mass spectrometer. Eighteen compounds were identified representing 90.56% of the oil. The major constituents were described as alpha-pinene (27.02%), sabinene (15.25%), cedrenol (14.53%) germacrene (9.61%) geraniol formate (6.82%), and caryophylene (5.38%). EOAM (10-100 microg/ml) elicited reversible relaxation of spontaneous contractions of isolated rabbit jejunal smooth muscle preparations, and similarly inhibited contractions induced by high-potassium solution ([K(+)](o) = 76 mM) and carbachol (10(-6) M) with IC(50) values of 14.98 and 27.29 microg/ml, respectively. Furthermore, EOAM exhibited an inhibitory effect on the dose-response curves induced by carbachol and CaCl(2) on rat jejunum preparations. These results clearly demonstrated the antispasmodic effect of EOAM which was strongly suggested to be mainly due to an inhibitory effect on Ca(2+) influx through the membrane of jejunal smooth muscle cells.

Pharmacological and phytochemical study on a Sisymbrium officinale Scop. extract.

ETHNOPHARMACOLOGICAL RELEVANCE: The aerial parts of Sisymbrium officinale Scop. are commonly used to treat airway ailments, moreover in antiquity the herbal drug was reputed to possess anticancer properties. The results obtained in present work support the traditional use and the properties ascribed to Sisymbrium officinale. AIM OF THE STUDY: In order to give a scientific basis to the traditional uses of Sisymbrium officinale, this study was aimed to evaluate in vitro the myorelaxant activity, the antimicrobial properties and the antimutagenic effect of an aqueous dry extract of the aerial parts of the plant. A phytochemical characterization of the extract was also performed. MATERIALS AND METHODS: The myorelaxant activity was studied against the contractions induced by carbachol, histamine and leukotriene C(4), in isolated guinea-pig trachea. The antimicrobial activity was tested against six bacteria and one yeast. The Ames test, performed by the preincubation method, was used to study the antimutagenic activity of the extract by its capability to inhibit the mutagenic effect of 2-nitrofluorene, sodium azide, methyl methanesulfonate and 2-aminoanthracene, in Salmonella typhimurium TA98, Salmonella typhimurium TA100 and Escherichia coli WP2uvrA strains. The chemical composition of the extract was analyzed by TLC and HPLC. RESULTS: Sisymbrium officinale showed to reduce the chemically-induced contractions of isolated guinea-pig trachea with major potency against leukotriene C(4) and histamine. The extract did not show any antibacterial activity. The Ames test showed a strong antimutagenic activity against 2-aminoanthracene, in Escherichia coli WP2uvrA and in Salmonella typhimurium TA98 strains. The phytochemical study highlighted the presence of putranjivine, the glucosinolate marker of Sisymbrium officinale, and of proline. CONCLUSIONS: The myorelaxant activity of Sisymbrium officinale offers a scientific basis to its use in traditional medicine. The strong antimutagenic effect suggests further studies to evaluate its possible chemopreventive activity.

Pharmacological basis for the medicinal use of Zanthoxylum armatum in gut, airways and cardiovascular disorders.

This study describes the gut, airways and cardiovascular modulatory activities of Zanthoxylum armatum DC. (Rutaceae) to rationalize some of its medicinal uses. The crude extract of Zanthoxylum armatum (Za.Cr) caused concentration-dependent relaxation of spontaneous and high K(+) (80 mM)-induced contractions in isolated rabbit jejunum, being more effective against K(+) and suggestive of Ca(++) antagonist effect, which was confirmed when pretreatment of the tissues with Za.Cr shifted Ca(++) concentration-response curves to the right, like that caused by verapamil. Za.Cr inhibited the castor-oil-induced diarrhea in mice at 300-1000 mg/kg. In rabbit tracheal preparations, Za.Cr relaxed the carbachol (1 microM) and high K(+)-induced contractions, in a pattern similar to that of verapamil. In isolated rabbit aortic rings, Za.Cr exhibited vasodilator effect against phenylephrine (1 microM) and K(+)-induced contractions. When tested in guinea pig atria, Za.Cr caused inhibition of both atrial force and rate of spontaneous contractions, like that caused by verapamil. These results indicate that Zanthoxylum armatum exhibits spasmolytic effects, mediated possibly through Ca(++) antagonist mechanism, which provides pharmacological base for its medicinal use in the gastrointestinal, respiratory and cardiovascular disorders.

Beta2-adrenoceptor-mediated tracheal relaxation induced by higenamine from Nandina domestica Thunberg.

The fruit of Nandina domestica Thunberg (ND, Berberidaceae) has been used to improve cough and breathing difficulties in Japan for many years, but very little is known about the constituent of ND responsible for this effect. We have recently reported that the crude extract from ND (NDE) inhibits histamine- and serotonin-induced contraction of isolated guinea pig trachea, and the inhibitory activity was not explained by nantenine, a well-known alkaloid isolated from ND. To explore other constituent(s) of NDE with tracheal smooth muscle relaxant activity, we fractionated NDE and assessed the pharmacological effects of the fractions using isolated guinea pig tracheal ring preparations. NDE was introduced into a polyaromatic absorbent resin column and stepwise eluted to yield five fractions, among which only the 40 % methanol fraction was active in relaxing tracheal smooth muscle precontracted with histamine. Further separation of the 40 % methanol fraction with high-performance liquid chromatography yielded multiple subfractions, one of which was remarkably active in relaxing histamine-precontracted trachea. Chemical analysis with a time-of-flight mass spectrometer and nuclear magnetic resonance spectrometer identified the constituent of the most active subfraction as higenamine, a benzyltetrahydroisoquinoline alkaloid. The potency and efficacy of the active constituent from NDE in relaxing trachea were almost equivalent to synthetic higenamine. In addition, the effect of the active constituent from NDE was competitively inhibited by the selective beta (2)-adrenoceptor antagonist ICI 118,551. These results indicate that the major constituent responsible for the effect of NDE is higenamine, which probably causes the tracheal relaxation through stimulation of beta (2) adrenoceptors.

Muscarinic, Ca(++) antagonist and specific butyrylcholinesterase inhibitory activity of dried ginger extract might explain its use in dementia.

Ginger rhizome (Zingiber officinale) has been used for centuries to treat dementia in South Asia. This study was undertaken to possibly justify its use. A 70% aqueous/methanolic extract of dried ginger (Zo.Cr) was used. Zo.Cr tested positive for the presence of terpenoids, flavonoids, secondary amines, phenols, alkaloids and saponins. When tested on isolated rat stomach fundus, Zo.Cr showed a spasmogenic effect (0.03-5.00 mg mL(-1)); it relaxed the tissue at concentrations > or =5 mg mL(-1). The stimulant effect was resistant to blockade by hexamethonium and methysergide, but sensitive to atropine, indicating activity via muscarinic receptors. In atropinized (0.1 microM) preparations, Zo.Cr (0.3-3.0 mg mL(-1)) relaxed high K(+) (80 mM)-induced contractions, indicating Ca(++) antagonism in addition to the muscarinic effect. This possible Ca(++) antagonist activity was investigated in Ca(++)-free conditions, with the inhibitory effect of the extract tested against contractions induced by externally administered Ca(++). Zo.Cr (0.1-0.3 mg mL(-1)), similar to verapamil (0.03-0.10 microM), shifted the contractions induced by externally administered Ca(++) to the right, thus suggesting an inhibitory interaction between Zo.Cr and voltage-operated Ca(++) channels. Zo.Cr (0.1-3.0 microg mL(-1)) also potentiated acetylcholine peak responses in stomach fundus, similar to physostigmine, a cholinesterase inhibitor. Zo.Cr, in an in-vitro assay, showed specific inhibition of butyrylcholinesterase (BuChE) rather than acetylcholinesterase enzyme. Different pure compounds of ginger also showed spasmolytic activity in stomach fundus, with 6-gingerol being the most potent. 6-Gingerol also showed a specific anti-BuChE effect. This study shows a unique combination of muscarinic, possible Ca(++) antagonist and BuChE inhibitory activities of dried ginger, indicating its benefit in dementia, including Alzheimer's disease.

Achillea millefolium L. s.l. revisited: recent findings confirm the traditional use.

Yarrow (Achillea millefolium L. s.l.) is traditionally used in the treatment of inflammatory and spasmodic gastro-intestinal disorders, hepato-biliary complaints and inflammation. Now we could show that the flavonoids mediated the antispasmodic properties of yarrow, whereas the dicaffeoylquinic acids caused the choleretic effects. Moreover, we observed an in vitro-inhibition of human neutrophil elastase, a protease involved in the inflammatory process, by extracts and fractions from yarrow, which suggests additional mechanisms of antiphlogistic action. The presented results confirm the traditional use of yarrow.

Tyrosinase inhibitory pentacyclic triterpenes and analgesic and spasmolytic activities of methanol extracts of Rhododendron collettianum.

During the course of screening of medicinal plants of Pakistan for the isolation and structure elucidation of bioactive natural products, it was found that the methanol extract of the Rhododendron collettianum showed analgesic and spasmolytic activities. The methanol extract was then extracted with chloroform. Nine pentacyclic triterpenes were isolated from the chloroform extract and their structures were elucidated as erythrodiol (1), betulinic acid (2), maslinic acid (3), 2alpha,3alpha,23-trihydroxyolean-12-en-28-oic acid (4), bayogenin (5), arjunilic acid (6), methyl arjunolate (7), arjungenin (8) and 3beta, 23, 24-trihydroxyolean-12-en-28-oic acid (9). Among the triterpenes (1-9) tested, arjunilic acid (6) was found to be most potent. Their structure-activity relationship (SAR) showed that if the configuration of the -OH group at C-2 is changed from alpha to beta the potency is decreased. In most of the compounds the position and configuration of the -OH group was found to be important for the inhibitory potency against the enzyme tyrosinase. For the comparison, the standard tyrosinase inhibitors kojic acid (IC50=16.67 microm) and L-mimosine (IC50=3.68 microm) were used as controls.

Antispasmodic saponins from bulbs of red onion, Allium cepa L. var. Tropea.

A phytochemical analysis of the polar extract from the red bulbs of Allium cepa L. var. Tropea, typical of Calabria, a southern region of Italy, was performed extensively for the first time, leading to the isolation of four new furostanol saponins, named tropeoside A1/A2 (1a/1b) and tropeoside B1/B2 (3a/3b), along with the respective 22-O-methyl derivatives (2a/2b and 4a/4b), almost certainly extraction artifacts. High concentrations of ascalonicoside A1/A2 (5a/5b) and ascalonicoside B (6), previously isolated from Allium ascalonicum Hort., were also found. This is the first report of furostanol saponins in this A. cepa variety. The chemical structures of the new compounds were established through a combination of extensive nuclear magnetic resonance, mass spectrometry and chemical analyses. High concentrations of quercetin, quercetin 4(I)-glucoside, taxifolin, taxifolin 7-glucoside, and phenylalanine were also isolated. The new saponins were found to possess antispasmodic activity in the guinea pig isolated ileum; such an effect might contribute to explaining the traditional use of onion in the treatment of disturbances of the gastrointestinal tract.

Spasmolytic effects of baccharis conferta and some of its constituents.

The Nahua of the Mexican state of Veracruz use Baccharis conferta in the treatment of a variety of gastrointestinal illnesses, especially diarrhoea associated with gastrointestinal cramps. The aerial parts of B. conferta were investigated phytochemically and pharmacologically using the guinea pig ileum assay as a model (histamine, KCI and electric stimulation). The crude ethanolic extract showed a dose-dependent antispasmodic effect that was particularly strong in flavonoid-rich fractions (e.g. IC50 value for fraction E.3.1 from the ethyl acetate fraction, in histamine-induced contraction, 10 microg mL(-1)). Several flavonoids (apigenin-4',7-dimethylether, naringenin-4',7-dimethylether, pectolinarigenin and cirsimaritin) were isolated, while others were identified in complex fractions by GC-MS. The flavonoids play an important role in the antispasmodic activity of this indigenous drug. Additionally, oleanolic acid and its methyl ester as well as erythrodiol were isolated. Oleanolic acid methyl ester shows weak antibacterial activity against M. luteusand E. coli (20 microg/spot in a TLC assay). The phytochemical as well as the pharmacological data provide some in-vitro evidence forthe use of B. conferta in thetreatment of gastrointestinal cramps.

Variability in the content of the constituents of Hypericum perforatum L. and some commercial extracts.

Seven samples of Hypericum perforatum L. (St. John's wort) were collected throughout Tuscany; the dried extracts were assayed to determine the concentration of the constituents. Total flavonol content ranged from 4.58% to 15.90%; hypericins ranged from 0.05% to 0.11%; and hyperforins ranged from 1.37% to 20.80%. In addition, four commercially dried extracts were analyzed using the same high-performance liquid chromatographic (HPLC) method; their flavonol contents varied from 10.64% to 15.01%, hypericins varied from 0.03% to 0.20%, and hyperforins varied from 1.18% to 6.54%. The aim of this investigation was to evaluate the contents of the different constituents depending on environmental factors and drying and storage conditions of the wild samples. In addition, the contents of the constituents of the products available to the consumer that were related to quality and the relation of this to safety and efficacy were also evaluated.