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At least 109 records · Page 6Linked to original sources

A multidisciplinary approach to ritual enema scenes on ancient Maya pottery.

There are various enema scenes on classic Maya pottery, which undoubtedly represent rituals and may very well indicate that the ancient Maya took intoxicating enemas in a ritual context. This idea is quite contrary to the traditional view that the ancient Maya were a contemplative people, who did not indulge in ritual ecstasy. The occasional display of vomiting actors would seem to provide a plausible reason why the Maya opted for rectal application. Some scenes present a fair amount of evidence that an alcoholic beverage may have been taken rectally. Anecdotal experimental evidence suggests that an alcoholic liquid may certainly induce or intensify a state of inebriation, when it is administered via the rectal route. Other scenes open up the possibility that tobacco and the water lily or some other flowering plant may have served as an enema ingredient. The phytochemistry and psychopharmacology of tobacco are well documented and there can be little doubt that this herb may produce toxic effects, when it is taken in the form of a clyster. Unfortunately, little is still known about the constituents and pharmacological activity of the water lily. It is sometimes speculated that this plant is hallucinogenic, but experimental confirmation of this view is still awaited.

Central America↗

Ethnopharmacologic and phytochemical studies of the Thymelaeaceae.

The ethnobotany, ethnopharmacology and phytochemistry of the Thymelaeaceae are reviewed. Some members of this family find wide use commercially whilst others are used as deadly poisons or possess extreme irritant properties. The phytochemical evidence thus far available indicates that the daphnane and tigliane diterpene esters are clearly responsible for the toxic reactions observed, but chemotaxonomically it is not possible to predict which additional genera are likely to contain these toxins. Caution should therefore be exercised when studying members of this plant family.

Animals↗

Methods in ethnopharmacology.

A variety of pharmacological models are utilized in the evaluation of ethnomedicine. Most investigations are focused on developing new leads for therapeutic agents. However, there should be more efforts focused on the development of ethnomedicines because of their accessibility and acceptability in areas where modern medicine is not readily available. Testing methods to identify the active agents must be carefully selected utilizing information from ethnoanthropology, ethnobotany, phytochemistry, toxicology and pharmacology. New pharmacological models focused on cellular and molecular mechanisms can be used for ethnomedical evaluations but with great caution since they are based on known mechanisms of actions and limited by knowledge of the disease state.

Animals↗

Plant-derived triterpenoid sweetness inhibitors.

Considerable recent attention has been focused on naturally occurring compounds with taste-modifying activity, which are of potential use in both dietary sweetness management and in gaining a better understanding of the sweet taste sensation. This review summarizes information on the phytochemistry and biological activity of more than 40 triterpenoid sweetness inhibitors that have been isolated from the leaves of three medicinal plants, namely, Gymnema sylvestre R.Br. (Asclepiadaceae), Ziziphus jujuba P. Miller (Rhamnaceae), and Hovenia dulcis Thunb. (Rhamnaceae).

Drug Antagonism↗

Natural products research: perspectives from a major pharmaceutical company.

Natural products research continues to provide a tremendous variety of lead structures which are used as templates for the development of new drugs by the pharmaceutical industry. Advances in bioassay technology and in chemical methodology have combined to make natural products a cost effective source for new leads. While microbial products have been the mainstay of industrial natural products discovery, in recent years phytochemistry has again become a field of active interest. Drug discovery programs based on microbial products and phytochemicals are discussed and contrasted.

Animals↗

Biomolecular NMR: a chaperone to drug discovery.

Biomolecular NMR now contributes routinely to every step in the development of new chemical entities ahead of clinical trials. The versatility of NMR--from detection of ligand binding over a wide range of affinities and a wide range of drug targets with its wealth of molecular information, to metabolomic profiling, both ex vivo and in vivo--has paved the way for broadly distributed applications in academia and the pharmaceutical industry. Proteomics and initial target selection both benefit from NMR: screenings by NMR identify lead compounds capable of inhibiting protein-protein interactions, still one of the most difficult development tasks in drug discovery. NMR hardware improvements have given access to the microgram domain of phytochemistry, which should lead to the discovery of novel bioactive natural compounds. Steering medicinal chemists through the lead optimisation process by providing detailed information about protein-ligand interactions has led to impressive success in the development of novel drugs. The study of biofluid composition--metabonomics--provides information about pharmacokinetics and helps toxicological safety assessment in animal model systems. In vivo, magnetic resonance spectroscopy interrogates metabolite distributions in living cells and tissues with increasing precision, which significantly impacts the development of anticancer or neurological disorder therapeutics. An overview of different steps in recent drug discovery is presented to illuminate the links with the most recent advances in NMR methodology.

Drug Design↗

Apoptotic activity of betulinic acid derivatives on murine melanoma B16 cell line.

The mitochondrion plays a crucial role in the process of apoptosis and has thus become one of the targets for the search for potential chemotherapeutic agents. Betulinic acid [3beta-hydroxy-lup-20(19)lupaen-28-carbonic acid], a lupane-type triterpene which is abundant in many plant species, has been shown to exert a direct effect on the mitochondria and subsequent apoptosis in melanoma cells. Chemical synthesis and modification of betulinic acid are being explored to develop more potent derivatives. We present here the apoptotic activity of several natural derivatives of betulinic acid which were isolated from the roots of a Chinese medicinal herb, Pulsatilla chinensis (Bge) Regel [Ye, W., Ji, N.N., Zhao, S.X., Liu, J.H., Ye, T., McKervey, M.A., Stevenson, P., 1996. Triterpenoids from Pulsatilla chinensis. Phytochemistry 42, 799-802]. Of the five compounds tested, 3-oxo-23-hydroxybetulinic acid was the most cytotoxic on murine melanoma B16 cells (IC50=22.5 microg/ml), followed by 23-hydroxybetulinic acid and betulinic acid (IC50=32 and 76 microg/ml, respectively), with lupeol and betulin exhibiting the weakest cytotoxicity (IC50> or =100 microg/ml). Exposure of B16 cells to betulinic acid, 23-hydroxybetulinic acid and 3-oxo-23-hydroxybetulinic acid caused a rapid increase in reactive oxidative species production and a concomitant dissipation of mitochondrial membrane potential in a dose- and time-dependent manner, which resulted in cell apoptosis, as demonstrated by fluorescence microscopy, gel electrophoresis and flow-cytometric analysis. Cell cycle analysis further demonstrated that both 3-oxo-23-hydroxybetulinic acid and 23-hydroxybetulinic acid dramatically increased DNA fragmentation at the expense of G1 cells at doses as low as 12.5 and 25 microg/ml, respectively, thereby showing their potent apoptotic properties. Our results showed that hydroxylation at the C3 position of betulinic acid is likely to enhance the apoptotic activity of betulinic acid derivatives (23-hydroxybetulinic acid and 3-oxo-23-hydroxybetulinic acid) on murine melanoma B16 cells.

Animals↗

The Goodeniaceae.

The Goodeniaceae family contributes some of the more spectacular wildflowers found on the Australian continent. The bright and vibrant colours that characterise members of the family has attracted much horticultural interest. A number of species have traditionally been used for medicinal purposes by indigenous communities, and the phytochemistry of some has been investigated. These aspects are considered in this review to determine correspondence between the reputed medicinal effects and the bioactivity of the secondary metabolites produced.

Asteraceae↗

Preliminary toxicity and phytochemical studies of the stem bark aqueous extract of Musanga cecropioides in rats.

These studies were designed to determine the preliminary oral toxicity profile of the crude aqueous stem bark extract of Musanga cecropioides (MCW) in adult Sprague-Dawley rats and its active chemical constituents by way of phytochemistry. The acute oral toxicity study was conducted using limit dose test of Up and Down Procedure according to the OECD/OCDE Test Guidelines on Acute Oral Toxicity (AOT425statPgm, version: 1.0) at a limit dose of 3,000 mg/kg body weight/oral route. Repeat dose oral toxicity studies were conducted by daily oral dosing of 750 mg/kg body weight of MCW dissolved in 1 ml of 0.9% saline and 1 ml of 0.9% saline to rats in the test and control groups, respectively, for 28 days. On day 29, blood samples for bioassays were collected by cardiac puncture under diethyl ether anesthesia. The phytochemical analysis was conducted using standard procedures. The LD(50) estimate of the extract was calculated to be greater than 3,000 mg/kg body weight/oral route. The extract caused a significant (P<0.05) decrease in weight gain, differential eosinophil count and increase in serum creatinine but did not affect the organ weights, other serum electrolytes (Na(+), K(+), HCO(3)(-)), liver enzymes and other hematological indices in test rats. Its phytochemical analysis showed it contains saponins, flavonoids, alkaloids, tannins, phlobatannins, glycosides, reducing sugars and anthraquinones. These results show that the aqueous extract of Musanga cecropioides is relatively safe toxicologically when administered orally. Thus, its use in folkloric medicine as an oral antihypertensive is relatively safe when used over the tested period.

Animals↗

Punica granatum (pomegranate) and its potential for prevention and treatment of inflammation and cancer.

The last 7 years have seen over seven times as many publications indexed by Medline dealing with pomegranate and Punica granatum than in all the years preceding them. Because of this, and the virtual explosion of interest in pomegranate as a medicinal and nutritional product that has followed, this review is accordingly launched. The pomegranate tree, Punica granatum, especially its fruit, possesses a vast ethnomedical history and represents a phytochemical reservoir of heuristic medicinal value. The tree/fruit can be divided into several anatomical compartments: (1) seed, (2) juice, (3) peel, (4) leaf, (5) flower, (6) bark, and (7) roots, each of which has interesting pharmacologic activity. Juice and peels, for example, possess potent antioxidant properties, while juice, peel and oil are all weakly estrogenic and heuristically of interest for the treatment of menopausal symptoms and sequellae. The use of juice, peel and oil have also been shown to possess anticancer activities, including interference with tumor cell proliferation, cell cycle, invasion and angiogenesis. These may be associated with plant based anti-inflammatory effects, The phytochemistry and pharmacological actions of all Punica granatum components suggest a wide range of clinical applications for the treatment and prevention of cancer, as well as other diseases where chronic inflammation is believed to play an essential etiologic role.

Animals↗

Cestrum diurnum leaf as a source of 1,25(OH)2 Vitamin D3 improves egg shell thickness.

A continuing concern of the poultry industry is the high incidence (12%) of egg losses in the laying house due to poor egg shell quality. Calcium (Ca) homeostasis is a key factor in egg shell formation. The economy of Ca utilisation is under the control of Vitamin D(3), particularly its active metabolite 1,25-dihydroxy cholecalciferol [1,25(OH)(2)D(3)]. Supplementation of 1,25(OH)(2)D(3) has been shown to increase specific gravity, shell thickness and shell weight of the egg. However, commercially available synthetic 1,25(OH)(2)D(3) is very expensive. Earlier studies from our Institute [Phytochemistry 37 (1994) 677] have identified a cheap, natural and rich source of 1,25(OH)(2)D(3) in the leaves of Cestrum diurnum (CD), a member of the Solanaceae family. In this study, CD leaves were explored as a source of 1,25(OH)(2)D(3) in the feed of layer birds to improve the egg shell thickness. Fifteen-week-old white leghorn layers were divided into four treatments of 60 birds each and as follows: (I) normal diet with Vitamin D(3), (II) normal diet with Vitamin D(3) + CD, (III) normal diet without Vitamin D(3) and, (IV) normal diet without Vitamin D(3) + CD powder. CD leaf powder was incorporated in to the feed at 0.3% level. The experimental feeding was continued up to 72 weeks of age of the birds. Weekly food intake and daily egg production were noted throughout the experimental period and the specific gravity of the eggs, feed consumed to lay one egg and egg shell thickness were determined. Incorporation of CD leaves in the feed had the maximal effect on all the parameters studied. The feed consumed to lay one egg was 20 g less than the control group. The specific gravity of the egg was higher by 0.005, than the control egg, indicating a 5% decrease in the breakage of eggs in CD fed chicks. Also there was a significant increase (P < 0.001) in egg shell thickness. The data suggest that incorporation of CD leaf powder in the feed of poultry layers increased the egg shell thickness, which in turn could decrease the economic loss due to breakage of eggs.

Animals↗

A furanocoumarin and polymethoxylated flavonoids from the Yucatec Mayan plant Casimiroa tetrameria.

As part of an ongoing study of the medicinal plants of the Yucatec Maya, Casimiroa tetrameria was investigated for its phytochemistry. From an ethyl acetate partition of an ethanol extract of the leaves, eight flavonoids and a furanocoumarin were isolated and characterised as 5,6,2',3',5',6'-hexamethoxyflavone, 5,6,2',3',6'-pentamethoxyflavone and 5-methoxy-8-(3''-hydroxymethyl-but-2''-enyloxy)-psoralen using a combination of 1H, 13C NMR and NOESY spectroscopy.

Casimiroa↗

The shape of things to come: structural and synthetic studies of taxol and related compounds.

The history of the development of Taxol (paclitaxel) as an anticancer drug is reviewed, and some aspects of the phytochemistry of Taxus species and of the medicinal chemistry of taxol are discussed. The nature of the taxol-tubulin interaction is then described, with an emphasis on studies that led to the discovery and experimental proof of the T-taxol conformation as the tubulin-binding conformation of taxol. The implications of this conformation for future drug development are also briefly covered.

Animals↗

Painting new pathways: Castilleja enters the genomic era.

Castilleja (Orobanchaceae), commonly known as Indian paintbrush, is a genus of approximately 200 hemiparasitic species found primarily across the Americas. Long studied for its taxonomic complexity, vibrant floral displays, and ecological interactions with host plants, Castilleja has recently emerged as a versatile research system spanning parasitic biology, specialized metabolism, conservation genetics, and pharmacology. The availability of whole-genome sequencing is transforming the field, revealing expanded gene families involved in host recognition, enabling genomic species delimitation of cryptic taxa, and providing frameworks for mapping biosynthetic pathways of bioactive compounds, including iridoid glycosides and phenylethanoid glycosides. This review synthesizes advances across these disciplines and highlights how genomics serves as an integrative force connecting taxonomy, ecology, phytochemistry, and parasitic biology in this genus.

Castilleja↗

Jolkinolide B induces neuroendocrine differentiation of human prostate LNCaP cancer cell line.

Euphorbia fischeriana is a Chinese herbal medicine which has been reported to possess chemotherapeutic effects, yet the underlying mechanism is unclear. In order to understand its possible anti-tumor property, we have isolated a number of chemical compounds from the roots of this plant [Phytochemistry 52 (1999) 117] and studied their in vitro effects by using human prostate LNCaP cancer cell line. Among the six compounds tested, jolkinolide B exhibited the most potent anti-proliferative activity (IC(50)=12.5 microg/mL=40 microM) and it inhibited DNA synthesis by down-regulating bromodeoxyuridine (BrdU) incorporation in LNCaP cells in a dose-dependent manner. Jolkinolide B, at concentrations up to 25 microg/mL, induced G1 arrest and neuroendocrine differentiation of LNCaP cells. Immunoblotting analysis confirmed the increased expression of neuroendocrine markers, keratin 8/18 (K8/18) and neuron specific enolase (NSE), in these cells. Apoptotic bodies and DNA fragmentation were observed by fluorescence microscopy and flow cytometry when the cells were exposed to a concentration higher than 25 microg/mL jolkinolide B. Taken all data together, jolkinolide B seems to play a role in the regulation of proliferation, differentiation, and apoptosis of LNCaP cells.

Antineoplastic Agents, Phytogenic↗

Isolation and structure elucidation of a highly haemolytic saponin from the Merck saponin extract using high-field gradient-enhanced NMR techniques.

Saponins SAPO50 and SAPO30, of which SAPO50 is highly haemolytic, have been isolated from the commercial Merck Saponin. Their structures have been determined exclusively by high-field gradient-enhanced NMR methods. The 1H and 13C NMR spectra of these saponins in pyridine-deuterium oxide have been assigned by homonuclear and heteronuclear correlation experiments. Anomeric configurations were obtained by combined use of 1JCH, 3JH-1.H-2, and 1D-NOESY data. Sugar residues were identified by use of 3JHH values obtained from their subspectra recorded using an optimized 1D-zeta-TOCSY sequence. Linkage assignments were made using the ge-HMBC and 1D-NOESY spectra. This study shows that SAPO50 represents a hitherto undescribed saponin with the following structure: 3-O-beta-D-xylopyranosyl-(1-->3)-[beta-D-galactopyranosyl- (1-->2)]-beta-D-glucuronopyranosyl gypsogenin 28-O-(6-deoxy-beta-D-glucopyranosyl)-(1-->4)-[beta-D-xylopyranosyl-(1--> 3)- beta-D-xylopyranosyl-(1-->4)]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D- fucopyranoside. SAPO30, however, corresponds to a saponin previously described [D. Frechet, B. Christ, B. Monegier du Sorbier, H. Fischer, and M. Vuilhorgne, Phytochemistry, 30 (1991) 927-931].

Carbohydrate Conformation↗

Contributions of Jeffrey Harborne and co-workers to the study of anthocyanins.

Jeffrey Harborne and his co-workers have played a unique role in the over-all study of plant pigments and of anthocyanins in particular through their many publications and through Jeffrey's editorial work with Phytochemistry. Jeffrey has made important contributions to our understanding of the separation and structural identification of anthocyanins; to co-pigmentation; and to the role of anthocyanins in systematics and ecology in both reproductive and vegetative tissues. This work has had considerable influence on much of the current research on the genetics and regulation of anthocyanin biosynthesis.

Anthocyanins↗

Polyphenolics of Salvia--a review.

Salvia is an important genus widely cultivated and used in flavouring and folk medicines. The genus has attracted great interest so much so that it has been the subject of numerous chemical studies. It is a rich source of polyphenols, with an excess of 160 polyphenols having been identified, some of which are unique to the genus. A large number of these polyphenolic compounds are apparently constructed from the caffeic acid building block via a variety of condensation reactions. The nature of these polyphenols which have been reported is compiled in this report together with some bioactivity data in an effort to show the rapid development in the phytochemistry and the therapeutic applications of the Salvia species.

Animals↗