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PubMed1988

Identification by methane chemical ionization gas chromatography/mass spectrometry of the products obtained by steam distillation and aqueous acid extraction of commercial Piper methysticum.

Bornyl cinnamate has been identified as a constituent of kava resin and of the steam distillate of Piper methysticum. 5-Hydroxydihydrokawain was identified in commercial samples of P. methysticum originating from Vanuatu provided an initial aqueous extraction was employed. Commercial preparations, and fresh samples of the root of this plant from Fiji, lacked this compound. Two previously described N-cinnamoyl pyrrolidine alkaloids were also observed along with stigmasterol in kava resin from Fiji and Vanuatu. The products derived from aqueous 2 M hydrochloric acid extraction of P. methysticum were determined from methane chemical ionization gas chromatography/mass spectrometry analysis which identified a series of hydroxylated compounds (15a-d) derived from formal decarbonylation of the parent kava lactones. The products (13a-c) of dehydration of these compounds were also observed. The efficiency of kava resin extraction from plant material by water (the traditional method of preparation of the kava beverage) was typically 5-10% of that recovered by direct extraction with an organic solvent.

Fiji↗
PubMed2004

Enhanced cognitive performance and cheerful mood by standardized extracts of Piper methysticum (Kava-kava).

The acute effects of the herbal anxiolytic Kava-kava (Piper methysticum G. Forster) on emotional reactivity and cognitive performance were investigated in a double-blind randomized placebo-controlled trial involving healthy volunteers. Subjects' reports of mood change were assessed with the state-trait-cheerfulness-inventory, which measures the three concepts of cheerfulness, seriousness and bad mood as both traits and states. Cognitive performance was examined with the Sperling partial report and the Sternberg item recognition task, which were used as an index for visual attention and short-term memory processing. The intake of a single dose of Kava extract (300 mg; p.o.) led to an increase in state cheerfulness, while the phytopharmacon did not influence state seriousness and bad mood. The mood-elevating effects of Kava were most prominent in trait cheerful subjects, indicating that trait cheerfulness moderated the drug-induced increase in cheerful mood. Furthermore, Kava improved the accuracy and the speed of performing the partial report and the item recognition task, indicative of a beneficial effect of the phytopharmacon on visual attention and short-term memory retrieval, respectively. Thus, unlike conventional benzodiazepine-type anxiolytics, which tend to impair cognitive performance and to increase the occurrence of negative affective states, Kava is a potent anxiolytic agent, which, additionally, can facilitate cognitive functioning and can increase positive affectivity related to exhilaration.

Adolescent↗
PubMedDate not supplied

High-performance liquid chromatography-coordination ion spray-mass spectrometry (HPLC-CIS/MS): a new tool for the analysis of non-polar compound classes in plant extracts using the example of Piper methysticum Forst.

An efficient method to characterise complex plant extracts is described using the example of Piper methysticum Forst. (kava; Piperaceae). The method is based on the on-line coupling of high-performance liquid chromatography to a new detection technique: coordination ion spray-mass spectrometry (CIS/MS). CIS/MS is a universal, novel ionisation technique improving selectivity as well as sensitivity. Charged complexes were formed through addition of central complexing ions such as sodium, silver and cobalt. The advantages of CIS/MS detection compared with the electrospray ionisation detection are discussed. The experimental set-up and the application of this simple and robust technique is described to show the its various fields of application in the analysis of plant extracts.

Chromatography, High Pressure Liquid↗
PubMed2006

PIPER: an FFT-based protein docking program with pairwise potentials.

The Fast Fourier Transform (FFT) correlation approach to protein-protein docking can evaluate the energies of billions of docked conformations on a grid if the energy is described in the form of a correlation function. Here, this restriction is removed, and the approach is efficiently used with pairwise interaction potentials that substantially improve the docking results. The basic idea is approximating the interaction matrix by its eigenvectors corresponding to the few dominant eigenvalues, resulting in an energy expression written as the sum of a few correlation functions, and solving the problem by repeated FFT calculations. In addition to describing how the method is implemented, we present a novel class of structure-based pairwise intermolecular potentials. The DARS (Decoys As the Reference State) potentials are extracted from structures of protein-protein complexes and use large sets of docked conformations as decoys to derive atom pair distributions in the reference state. The current version of the DARS potential works well for enzyme-inhibitor complexes. With the new FFT-based program, DARS provides much better docking results than the earlier approaches, in many cases generating 50% more near-native docked conformations. Although the potential is far from optimal for antibody-antigen pairs, the results are still slightly better than those given by an earlier FFT method. The docking program PIPER is freely available for noncommercial applications.

Antibodies↗
PubMed2003

Anxiolytic properties of Piper methysticum extract samples and fractions in the chick social-separation-stress procedure.

Piper methysticum extract (Kava kava) possesses anxiolytic properties. However, it is unknown whether these effects are best predicted by total kavalactone content or by one or more of its primary kavalactone constituents. Using the chick social separation-stress procedure as an anxiolytic bioassay, P. methysticum samples containing 12.8-100.0% total kavalactones (Exp. 1) and fractions containing 1-6 kavalactones of varying concentrations (0.1-67.5%; Exps. 2-3) were screened for activity and compared against a 5.0 mg/kg dose of chlordiazepoxide (CDP; Exp. 3). Eight-day-old chicks received IP injections of either vehicle or test compounds 30 min before being placed in the presence of two conspecifics or in isolation for a 3 min observation period. Dependent measures were ventral recumbency latency (sedation), distress vocalizations, and a measure of stress-induced analgesia (in Exps. 1 and 2 only). P. methysticum extract samples attenuated distress vocalizations in a concentration-dependent manner. The P. methysticum fraction that contained the highest concentration of dihydrokavain attenuated distress vocalizations in a manner equivalent to that of CDP. The extract samples and fractions that possessed anxiolytic properties did not possess the sedative properties found in CDP. Collectively, these findings suggest that dihydrokavain may be necessary and sufficient in mediating the anxiolytic properties of P. methysticum extract.

Animals↗
PubMed1996

Nutrient and antinutrient composition of three varieties of Piper species.

The proximate composition of three varieties of Piper guineense (Odusa-Ibibio/Efik) viz. 'Uyat Odusa' (cultivated and peppery), 'Eting-keni Ikot' (wild forest variety) and 'Eting-keni mben inyang' (wild, riverine variety), were determined using available standard methods. Also determined were mineral, antinutrient and ascorbate levels. The cultivated pepperic variety had the highest content of crude protein and moisture (18.9% and 97% respectively) while the wild, riverine variety had the highest content of ether extract, carbohydrate and calories (7.79%, 63.38% and 398 cals respectively). The cultivated variety had appreciable amounts of phosphorus (1.12 mg/100 g), potassium (1.2 mg/100 g), sodium (0.24 mg/100 g), zinc (0.18 mg/100 g), and copper (0.18 mg/100 g) while the forest variety contained more of calcium (12.38 mg/100 g), magnesium (1.21 mg/100 g) and iron (0.85 mg/100 g). The wild riverine variety appeared to have the least mineral content but had the highest ascorbate level of 173.4 mg/100 g. Of four antinutrients assayed, the cultivated pepperic one had the least quantities while the forest variety was highest in hydrocyanic acid (85.8 mg/100 g) and glucosinolates (0.20 mg/100 g). The wild riverine variety had the highest level of total oxalate (165.0 mg/100 g). These quantities are however far below documented toxic levels.

Adult↗
PubMed1979

Carcinogenicity examination of betel nuts and piper betel leaves.

A dry powder of betel nuts, piper betel leaves and lime was administered to rats. Epidermal thickening was frequently observed in the upper digestive tracts of rats in groups fed the betel nut diet mixed with lime and the betel leaves diet, and a forestomach papilloma was seen in 1 rat given betel leaves diet. These epidermal changes were scarcely seen in rats given either betel nut or normal diet alone.

Animals↗
PubMed1994

Kavapyrone enriched extract from Piper methysticum as modulator of the GABA binding site in different regions of rat brain.

Regional differences in the modulation of [3H] muscimol binding to GABAA receptor complexes by kavapyrones, compounds of the rhizome of the plant Piper methysticum which possess sedative activity, were demonstrated using membrane fractions obtained from target brain centers of kavapyrone action: hippocampus (HIP), amygdala (AMY) and medulla oblongata (MED), and from brain centers outside the main kavapyrone effects as frontal cortex (FC) and cerebellum (CER). The kava extract enhanced the binding of [3H] muscimol in a concentration-dependent manner with maximal potentiation of 358% over control in HIP followed by AMY and MED (main target brain centers). Minimal stimulation was observed in CER followed by FC. In contrast, apart from CER, the potency of kavapyrones was similar in the brain areas investigated with EC50 values ranging between 200 and 300 microM kavapyrones. Scatchard analysis revealed that the observed effects of kavapyrones were due to an increase in the number of binding sites (Bmax), rather than to a change in affinity. At a kavapyrone concentration of 500 microM the order of enhancement in Bmax was HIP = AMY > MED > FC > CER. When kavapyrones are included together with pentobarbital or HPO the two classes of compounds produced a more than additive, i.e., synergetic effect on [3H] muscimol binding. Our findings suggest that one way kavapyrones might mediate sedative effects in vivo is through effects on GABAA receptor binding.

Animals↗
PubMed2003

Quantitative elimination of Flavokavines A and B from Kava Kava (Piper methysticum G. Forst) by isoelectric focused adsorptive bubble separation.

Adsorptive bubble separation, though still rarely used, is a suitable method for enrichment of surface-active macromolecules such as enzymes and proteins. There is a lack of investigations with small molecules, which can also be separated from complex mixtures by this method. In this work, an aqueous extract of Kava Kava ( Piper methysticum G. Forst) was used as a model system. Enrichment of undesirable Flavokavine A (7) and Flavokavine B (8) in the foam was influenced by the pH value, the amount of saponin as surface active substance, and the flow rate of the foam-forming gas. Efficiency was highest with diluted samples at pH 6.5. Under these conditions, transfer of Kavapyrone (1-6) to the foam was negligible.

Adsorption↗
PubMed1992

Separation of insecticidal components from an extract of the roots of male Piper guineense (west African black pepper) by gas chromatography.

A petroleum ether extract of Piper guineense male roots showed insecticidal activity when tested against Musca domestica. Gas chromatography of the extract yielded four active fractions, one of which was a pure component which was identified by spectral and chemical methods as pellitorine (N-isobutyl-2E,4E-decadienamide). The root extract lost about half of its insecticidal potency during passage down the GLC column, and much of the residual activity was due to the presence of pellitorine. It was concluded that GLC facilitates the isolation of active components in a pure form, but causes some insecticidal components of the root extract to be lost.

Africa, Western↗
PubMed1985

Inhibitory action of Piper betle on the initiation of 7,12-dimethylbenz[a]anthracene-induced mammary carcinogenesis in rats.

When an aqueous extract of the leaves of Piper betle, a medicinal plant, was given orally at different dose levels during the initiation phase of 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary carcinogenesis in rats, higher doses of the extract inhibited the emergence of tumors. However, when the extract was fed to the rats bearing DMBA-induced mammary tumors for 8 weeks, no appreciable degree of inhibition of tumor growth was noticed. Betel leaf extract at the dose levels used in the present study did not affect the body weight gain among rats.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1993

Anticonvulsant effects of extracts of the west African black pepper, Piper guineense.

A water extract of the West African black pepper Piper guineense L. was tested for activity against audiogenic seizures in DBA/2 mice, and against seizures induced in T.O. mice by N-methyl-DL-aspartate (NMDLA), pentylenetetrazole (PTZ) and maximal electroschock. Single intraperitoneal doses of the extract produced significant protection of DBA/2 mice against audiogenic seizures. The highest of three doses tested produced 100% and 58% protection at 6 h and 18 h after treatment, respectively. The extract also protected T.O. mice against convulsions induced by NMDLA and maximal electroshock but it had no significant effect on PTZ-induced convulsions. The doses of the extract tested did not cause significant impairment of performance of T.O. mice on a rotarod test. The results indicate that the extract of P. guineense has prolonged anticonvulsant activity at doses which do not cause significant CNS depression.

Acoustic Stimulation↗
PubMed1995

C-fiber-evoked autonomic cardiovascular effects after injection of Piper betle inflorescence extracts.

Piper betle inflorescence extracts contain eugenol (6.2%) and safrole (78.9%). Intravenous injections of water extracts of P. betle inflorescence (PBE), eugenol, and safrole in rats induced hypotensive and bradycardiac effects, whereas both intraarterial and intrathecal injections of PBE, eugenol and safrole resulted in hypotensive and tachycardiac effects. Moreover, the effects of intravenous injections of PBE were reversed or inhibited by the pretreatment with bilateral vagotomy, atropine (1 mg/kg, i.p.) and capsaicin (100 mg/kg, s.c.). Effects of intraarterial injections of PBE on blood pressure were inhibited by the pretreatment with substance P (SP) antagonist (1 nmol, i.t.) and clonidine (2.5 micrograms, i.t.), while heart rate was only inhibited by the pretreatment with SP antagonist (1 nmol, i.t.). In addition, the tachycardia resulting from intrathecal injections of PBE was inhibited by pretreatment with propranolol (0.3 mg/kg, i.v.). Eugenol and safrole induced the same pattern on blood pressure and heart rate changes as PBE in rats after various treatments. This report suggests that acute administration of betel inflorescence extracts by different routes may activate C-fiber-evoked parasympathetic and sympathetic cardiovascular reflexes in rats.

Animals↗
PubMed1996

Antiamoebic activity of Piper longum fruits against Entamoeba histolytica in vitro and in vivo.

The fruits of Piper longum used in traditional remedies against intestinal distress have been tested for their efficacy against experimental caecal amoebiasis of rats. The ethanolic extract, hexane fraction, n-butanol soluble fraction exerted in vitro amoebicidal action at 1000 micrograms/mL and the chloroform fraction at 500 micrograms/mL. The ethanolic extract and piperine, a pure compound, from this plant material cured 90% and 40% of rats with caecal amoebiasis, respectively.

Alkaloids↗
PubMed2006

Inhibition of TNFalpha-induced activation of nuclear factor kappaB by kava (Piper methysticum) derivatives.

The inducible transcription factor nuclear factor kappaB (NF-kappaB) plays a central role in the regulation of immune, inflammatory and carcinogenic responses. While normal activation of NF-kappaB is required for cell survival and immunity, its deregulated expression is a characteristic of inflammatory and infectious diseases. In this study, we investigated the molecular mechanisms induced by lactones and chalcones isolated from Fijian kava (Piper methysticum) used in traditional medicine against urinary tract infections and asthma. In order to understand underlying regulatory mechanisms, inhibition of both NF-kappaB-driven reporter gene expression and TNFalpha-induced binding of NF-kappaB to a consensus response element was achieved at concentrations of 320 microM (flavokavain A), 175 microM (flavokavain B) and 870 microM (kavain and dihydrokavain). Moreover, kavain and flavokavains A and B treatment led to inhibition of both inhibitor of kappaB (IkappaB) degradation and subsequent translocation of p50 and p65 NF-kappaB subunits from the cytoplasm to the nucleus as shown by Western blot analysis. Additionally, kinase selectivity screening demonstrates that flavokavain A, but not kavain, nor flavokavain B, inhibits the IkappaB kinase (IKK) as well as PRAK (p38-regulated/activated kinase), MAPKAP-K3 (MAPK-activated protein kinase 3), DYRK1A (dual-specificity tyrosine-phosporylated and regulated kinase 1A) and Aurora B. Altogether, these results give a first insight into anti-inflammatory mechanisms triggered by traditionally used chemopreventive kava compounds.

Blotting, Western↗
PubMed2006

Translation and cultural adaptation of the Piper Fatigue Scale for use in Sweden.

The aim of this study was to translate and culturally adapt the revised Piper Fatigue Scale to Swedish. For translation, guidelines for cross-cultural adaptation were used. Two teams independently translated the instrument and two other teams produced back-translations, after which a multidisciplinary committee decided on a Swedish version. In pre-test interviews, ten cancer patients were encouraged to think out loud while completing the Swedish version. Their verbal responses were analysed and used for a second revision. The initial translations varied in words, expressions and grammar, shown in a lack of equivalence to the original instrument after back-translation. In order to establish semantic equivalence, the committee changed some grammatical constructions, and some words were replaced for experiential and conceptual equivalence. When analysing the pre-test, obscurities due to the phrasing of some items were revealed and dealt with in the second revision. This study does not fulfil the process of validation for a translated instrument but offers a sound basis for further accumulation of evidence for validity, and facilitates the choice of an appropriate instrument for studying cancer-related fatigue in Sweden.

Activities of Daily Living↗