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Ethnopharmacology of the Popoluca, Mexico: an evaluation.

Medicinal plants are an essential part of indigenous pharmaceutical systems. We studied the medicinal plants used by the Popoluca of the Sierra Santa Marta (Eastern Mexico). This study is part of a series on the ethnopharmacology of various Macro-Mayan groups. During 16 months of ethnobotanical fieldwork, 614 taxa used medicinally and 4488 individual use-reports were documented. The data are analysed using the concept of the "healers' consensus" in order to identify culturally important medicinal plants. The medicinal uses of the plants were grouped into 13 illness categories. The responses for each species were summarized for each of the categories and were ordered by frequency of mention. The most frequently recorded medicinal plants of the Popoluca are Hamelia patens, used to stop bleeding from wounds, and Byrsonima crassifolia, used against diarrhoea. The high-ranked medicinal species were assessed pharmacognostically using published phytochemical and pharmacological data. Popoluca medicinal uses were fairly consistent with published data on active ingredients for those plants for which such data exist. However, data is still lacking for many other species. Toxicological studies are particularly scarce. This study will be used as a basis for subsequent studies on the pharmacology and phytochemistry of medicinal plant species.

Animals↗

Soybean glycinin A1aB1b subunit has a molecular chaperone-like function to assist folding of the other subunit having low folding ability.

Soybean (Glycine max L.) glycinin is composed of five subunits which are classified into two groups (group I: A1aB1b, A1bB2, and A2B1a; group II: A3B4 and A5A4B3). All the common soybean cultivars contain both group I and II subunits (Maruyama, N. et al., Phytochemistry, 64, 701-708 (2003)). The biosynthesis of group I starts earlier compared with that of the A3B4 subunit during seed development (Meinke, D.W. et al., Planta, 153, 130-139 (1981)). We have revealed that group I A1aB1b was mostly expressed as a soluble protein, but that A3B4 was expressed mainly as an insoluble protein in Escherichia coli under the same expression conditions; namely, A1aB1b had higher folding ability than A3B4. We therefore assumed that A1aB1b assists folding of group II subunits like a molecular chaperone does. In order to ascertain this, A1aB1b and A3B4 were co-expressed in E. coli. All of the expressed proteins of A3B4 were recovered in a soluble fraction. To confirm this result, we also co-expressed A1aB1b with modified A3B4 versions having extremely low folding ability. All expressed modified A3B4 versions were soluble. These results clearly suggest that A1aB1b has a molecular chaperone-like function in their folding.

Cloning, Molecular↗

Invasive plant suppresses the growth of native tree seedlings by disrupting belowground mutualisms.

The impact of exotic species on native organisms is widely acknowledged, but poorly understood. Very few studies have empirically investigated how invading plants may alter delicate ecological interactions among resident species in the invaded range. We present novel evidence that antifungal phytochemistry of the invasive plant, Alliaria petiolata, a European invader of North American forests, suppresses native plant growth by disrupting mutualistic associations between native canopy tree seedlings and belowground arbuscular mycorrhizal fungi. Our results elucidate an indirect mechanism by which invasive plants can impact native flora, and may help explain how this plant successfully invades relatively undisturbed forest habitat.

Brassicaceae↗

Occurrence and characterization of a UDP-glucose:hydroxamic acid glucosyltransferase isolated from wheat (Triticum aestivum) seedlings.

Cyclic hydroxamic acid glucosides are present at high concentrations immediately after germination in wheat (Triticum aestivum L.). Changes in the activity of UDP-Glucose:cyclic hydroxamic acid glucosyltransferase (EC 2.4.1.-) in wheat were investigated using the cyclic hydroxamic acids 2.4-dihydroxy-1,4-benzoxazin-3-one (DIBOA) and its 7-methoxy derivative (DIMBOA) as sugar acceptors. Glucosyltransferase activity on both substrates was detected in dry seeds, with activity increasing after imbibition, peaking in shoots and roots 36-48 hours after imbibition and decreasing thereafter. The transience of glucosyltransferase activity was concurrent with the transient occurrence of the hydroxamic acid glucosides [Nakagawa E., Amano T., Hirai N., and Iwamura H. (1995) Phytochemistry 38, 1349-1354], suggesting that glucosyltransferases regulate the accumulation of hydroxamic acid glucosides in wheat seedlings. Two peaks in activity of UDP-Glucose:DIMBOA glucosyltransferase were detected using a Mono Q column, indicating the presence of at least two isozymes of this glucosyltransferase. The enzyme in the major peak was purified about 1500-fold and shown to be in a monomeric form with a molecular mass of 47 or 49 kDa. The enzyme reacted strongly with DIMBOA, less so with DIBOA. The enzyme of the minor peak on the Mono Q chromatogram, which was also a monomeric enzyme with a molecular mass of 47 kDa, showed similar substrate specificity to that of the major peak enzyme.

Chromatography, Affinity↗

Insecticidal activity of synthetic amides on Spodoptera frugiperda.

The phytochemistry of the genus Piper (Piperaceae) has been widely studied due to the biological properties of amides from these plants. In this work, we have synthesized and evaluated the toxic effect of 11 amides against the fall armyworm Spodoptera frugiperda larvae. The naturally occurring piperine was also evaluated. The most active amide was N-[3-(3',4'-methylenedioxyphenyl)-2-(E)-propenoyl]piperidine with a LD50 of 1.07 microg mg(-1) larvae. This amide was also evaluated by ingestion.

Amides↗

Biodynamic constituents in the Mexican morning glories: purgative remedies transcending boundaries.

Jalap, a pre-Hispanic herbal remedy still considered a useful laxative, is an ingredient in some over-the-counter products sold by herbalists in contemporary Mexico. The purgative crude drugs are prepared from the roots of several morning glories species which all have been identified as members of the Ipomoea genus (Convolvulaceae). Their incorporation as therapeutical agents into Europe is an outstanding example of the assimilation of botanical drugs from the Americas as substitutes for traditional Old World remedies. Phytochemical investigations on the resin glycosides, main constituents of these drugs, were initiated during the second half of the XIX century; however, the structures of their active ingredients had remained poorly known, and still are for some members of these purgative root species. Modern analytical techniques with higher resolution capabilities (HPLC) for the isolation of the active principles of these crude drugs used in conjunction with powerful spectroscopic methods (high field NMR) have facilitated the investigation of these relevant, to the herbal product market, convolvulaceous species during the last decade. The advantages and limitations of theses techniques will be discussed. This review will also describe the ethnobotanical information associated with the Mexican morning glory species and how the traditional usages of these plants have played an important role in the selection of these materials for chemical studies. Little is as yet known about either the mechanism of purge action caused by the resin glycosides or the ecological significance of these same compounds for the producing plants. Over the five centuries of Mexican herbal medicine, one hundred years of phytochemistry has only partially elucidated the active ingredients of the jalap roots but has exemplified how to further contemporary drug discoveries through the investigation of those plants traditionally held to be economically and medicinally important in developing countries.

Cathartics↗

Activity and biological effects of neem products against arthropods of medical and veterinary importance.

Botanical insecticides are relatively safe and degradable, and are readily available sources of biopesticides. The most prominent phytochemical pesticides in recent years are those derived from neem trees, which have been studied extensively in the fields of entomology and phytochemistry, and have uses for medicinal and cosmetic purposes. The neem products have been obtained from several species of neem trees in the family Meliaceae. Six species in this family have been the subject of botanical pesticide research. They are Azadirachta indica A. Juss, Azadirachta excelsa Jack, Azadirachta siamens Valeton, Melia azedarach L., Melia toosendan Sieb. and Zucc., and Melia volkensii Gürke. The Meliaceae, especially A. indica (Indian neem tree), contains at least 35 biologically active principles. Azadirachtin is the predominant insecticidal active ingredient in the seed, leaves, and other parts of the neem tree. Azadirachtin and other compounds in neem products exhibit various modes of action against insects such as antifeedancy, growth regulation, fecundity suppression and sterilization, oviposition repellency or attractancy, changes in biological fitness, and blocking development of vector-borne pathogens. Some of these bioactivity parameters of neem products have been investigated at least in some species of insects of medical and veterinary importance, such as mosquitoes, flies, triatomines, cockroaches, fleas, lice, and others. Here we review, synthesize, and analyze published information on the activity, modes of action, and other biological effects of neem products against arthropods of medical and veterinary importance. The amount of information on the activity, use, and application of neem products for the control of disease vectors and human and animal pests is limited. Additional research is needed to determine the potential usefulness of neem products in vector control programs.

Animals↗

Heterochromatin banding patterns in Rutaceae-Aurantioideae--a case of parallel chromosomal evolution.

The heterochromatin banding patterns in the karyotypes of 17 species belonging to 15 genera of Rutaceae subfamily Aurantioideae (= Citroideae) were analyzed with the fluorochromes chromomycin (CMA) and 4'-6-diamidino-2-phenylindole-2HCl (DAPI). All species were diploids, except one tetraploid (Clausena excavata) and two hexaploids [Glycosmis parviflora agg. (aggregate) and G. pentaphylla agg.]. There are only CMA/DAPI bands, including those associated with the nucleolus. Using recent cpDNA (chloroplast DNA) sequence data as a phylogenetic background, it becomes evident that generally more basal genera with rather plesiomorphic traits in their morphology, anatomy, and phytochemistry exhibit very small amounts of heterochromatin (e.g., Glycosmis, Severinia, Swinglea), whereas relatively advanced genera from different clades with more apomorphic characters display numerous large CMA bands (e.g., Merrillia, Feroniella, Fortunella). Heterochromatin increase (from 0.7 to 13.7%) is interpreted as apomorphic. The bands are mostly located in the larger chromosomes and at telomeric regions of larger arms. However, one of the largest chromosome pair has been conserved throughout the subfamily with only very little heterochromatin. The heterochromatin-rich patterns observed in different clades of Aurantioideae appear quite similar, suggesting a kind of parallel chromosomal evolution. In respect to the current classification of the subfamily, it is proposed to divide Murraya s.l. (sensu lato) into Bergera and Murraya s.s. (sensu stricto) and to place the former near Clausena into Clauseneae s.s. and the latter together with Merrillia into Citreae s.l. The subtribes recognized within Clauseneae s.s. and Citreae s.l. appear heterogeneous and should be abandoned. On the other hand, the monophyletic nature of the core group of Citrinae, i.e., the Citrus clade with Eremocitrus, Microcitrus, Clymenia, Poncirus, Fortunella, and Citrus, is well supported.

Journal Article↗

On the "activation" of cytokinins.

A number of cytokinin analogs containing modifications in the heterocyclic moiety were prepared. These compounds were tested for activity as cytokinins and anticytokinins in the tabacco bioassay and the results were used to determine whether any position(s) of the heterocyclic nucleus of cytokinins may require derivatization as part of an over-all "activation" process. 3-substituted 4-alkylaminopyrazolo [3,4-d]pyrimidines and 4-alkylaminopyrrolo[2,3-d]pyrimidines, for example, have (substituted) carbon rather than nitrogen atoms at positions 3 and 5, respectively (analogous to position 7 in purines) and would be predicted to be metabolically stable at these positions. The finding that these compounds had cytokinin activity suggested that modification at the metabolically stable positions. The finding that these compounds had cytokinin activity suggested that modification at the metabolically stable position, and by extension at position 7 in cytokinin analogues which are purines, is not a prerequisite for the expression of cytokinin activity. Similar consideration of other heterocyclic analogs which have cytokinin activity suggests that the active form of a cytokinin can be the exogenous compound itself. Certain structural analogs of cytokinins were found to inhibit the growth of tobacco callus promoted by 6-(3-methyl-2-butenylamino)purine. These compounds were studied as potential cytokinin antagonists, i.e. having activity analogous to the 7-alkylamino-3-methylpyrazolo[4,3-d]pyrimidines (Hecht, S. M., 2068-2610; Skoog, F., Schmitz, R.Y., Hecht, S.M., and Bock, R. M. (1973) Phytochemistry 12, 25-37). The activity of these compounds is discussed and criteria are proposed to distinguish between those species which are specific anticytokinins and those which otherwise inhibit growth.

Biological Assay↗

[A-ring formylated flavonoids and oxoaporphinoid alkaloid from Dasymaschalon rostratum Merr. et Chun].

OBJECTIVE: To study the chemical components in the stem of Dasymaschalon rostratum. METHOD: The components were extracted with solvent, separated and purified with chromatographic methods, identified by NMR, MS, UV, IR and physicol-chemical constants. RESULTS: Three A-ring-formylated flavonoids and one oxoaporphinnoid aikaloid were isolated and identified as lawinal, unonal, isounonal and 7-oxodehydroasimilobine. CONCLUSION: All the four compounds were isolated for the first time from the genus Dasymaschalon. According to all the phytochemistry papers on Annonaceae, A-ring formylated flavonoids in this family were isolated from the genus Desmos for the first time. Thus, it is an interesting discovery in chemotaxonomy which reveals the close relationship between the two genera Desmos and Dasymaschalon.

Annonaceae↗

[Applied fundamental research of echinacea species].

Echinacea is a most famous "immune herb" in western countries, and continues to be the best selling herb for many years. For the last five years, our research group has cooperated with Institute of Medicinal Plants in Huairou District of Beijing, carrying out studies on Echinacea purpurea, which involved botany, cultivation, pharmacognosy, phytochemistry, quality control, pharmacology and toxicology of the species. Two other species introduced from Canada, Echinacea angustifolia and Echinacea pallida, were also included in the taxonomic, cultivated and pharmacognostic studies. The results acquired have opened up the path to introduce Echinacea species into Traditional Chinese Medicine, thus established the possibility of developing more promising drugs from them.

Animals↗

[The effects of the active constituents of Alisma orientalis on renal stone formation and bikunin expression in rat urolithiasis model].

OBJECTIVE: To evaluate the effects of the active constituents of Alisma orientalis on the expression of bikunin mRNA in rat urolithiasis model, and explore the mechanism of this traditional Chinese medicine on prevention of urinary calculi. METHODS: Modern phytochemistry and bioactivity guided isolation techniques were applied to extract the active constituents of Alisma orientalis. Hyperoxaluria and the renal oxalate calcium stone formation were induced in rats by infusion into the stomach with 1% ethylene glycol and 2% ammonium chloride. 30 adult male Wistar rats were randomized into 3 groups of 10 rats: control group, infused into the stomach with running water; stone-forming group, infused into the stomach with 1% ethylene glycol and 2% ammonium chloride so as to make into renal oxalate calcium stone model; and group of Alisma orientalis, infused into the stomach with 2% ammonium chloride and the constituents of Alisma orientalis. Four weeks after the rats were killed and their kidneys were taken out. Reverse transcription polymerase chain reaction technique was used to examine the bikunin mRNA expression levels in the rat renal tissues. The calcium oxalate deposits in the kidneys were detected by microscopy. The serum creatinnine and blood urea nitrogen levels, renal tissue calcium content, 24 h urinary calcium and oxalate excretion were also detected. RESULTS: In the group administered with the active constituents of Alisma orientalis, calcium oxalate deposits in the kidney, serum creatinnine and blood urea nitrogen levels, the bikunin mRNA expression levels, renal tissue calcium content and 24 h urinary calcium excretion were all significantly lower than those in the model group (the bikunin mRNA expression levels: 0.53 +/- 0.17 vs 0.71 +/- 0.25, P < 0.05; renal tissue calcium content: 4.70 mg/g +/- 0.08 mg/g vs 9.49 mg/g +/- 0.45 mg/g, P < 0.01; 24 h urinary calcium excretion: 37 micromol +/- 2 micromol vs 62 micromol +/- 2 micromol, P < 0.01). CONCLUSION: The active constituents of Alisma orientalis can down-regulate the bikunin mRNA expression, decrease the calcium oxalate formation in rat kidney, and inhibit the renal stone formation in rat urolithiasis model.

Alisma↗

[Histochemical localization of ginsenosides in Gynostemma pentaphyllum and the content changes of total gypenosides].

The light microscopy technique, histochemistry and phytochemistry methods were applied in the study of the localization of gingsenosides in the vegetative organs in Gynostemma pentaphyllum, and the content of total gypenosides related to different growing periods, organs and genders. The results showed that ginsenosides distributed mainly in the assimilating tissue and phloem parenchyma cells, very little in collenchyma, epidermis and phelloderm, and no coloration in xylem and pith parenchyma. The accumulation of gingsenosides in the leaf occupied first place, the stem came second, and the root was the lowest. The content of total gypenosides showed a changing trend from low to high, then to low, during the whole growing period from vegetative growth to florescence and fructescence, and withering period. The content in leaf is higher than that in stem, and of male is higher than of female. It is suggested that harvest the above-ground parts only and remaining the rhizome and root in florescence and fructescence (Sept. to Oct.) is of benefit to both improving herbal quality and quantity, and accelerating the sustainable utilization for wild resources.

Gynostemma↗

[Review of bioactivities of natural cycloartane triterpenoids].

Cycloartane triterpenoids, which exist widely in nature, are mainly distributed in Astragalus (Leguminosae) species, Trib. Cimicifuga (Ranunculaceae) and Thalictrium (Ranunculaceae) species and possess various bioactivities. Along with the development of isolation techniques of phytochemistry, more and more this kind of compounds are isolated and identified. However, bioactivity researches on the compounds are relatively lagged behind. Most researches are still in screening level, deficient in mechanism elucidation, short of action proven in vivo and SAR analysis. The author summarized the bioactivity of this kind of compounds from all aspects: anti-tumor, anti-virus, antibacterial, anti-inflammation, immune-regulatory, cardiovascular system, hepatic protection and so forth. This will be benefit for the further research and development of the compounds.

Animals↗

[Advances in research of chemical constituents and pharmacological activites of Ephedra].

The collected information is an attempt to cover the more recent developments in the phytochemistry and pharmacology of this genus. During the past years, alkaloids, flavonoids, volatile oils, organic acids, polysaccharides, tannins and phenolic constituents have been isolated from Ephedra. Pharmacological studies are described according to hypoglycemic effects, anticoagulated blood properties, depressurization, immunosuppressive activity, antioxidation and antivirus activity and so on. The information summarized here is intended to provid a rational foundation for the futher development and utilization of Ephedra which is rich in China.

Alkaloids↗

Transcriptional activity of a complex of wheat RNA polymerase II and nonhistone chromosomal protein (NHCP).

A protein stimulating RNA polymerase activity that has been isolated and partially characterized previously (Walerych, W., Fabisz-Kijowska, A. et al., 1982, Phytochemistry, 21, 1495-1507) was subjected to investigations on its possible involvement in transcription process. Affinity chromatography revealed that this protein strongly binds to RNA polymerase-Sepharose column. The NHCP protects the enzyme against thermal inactivation, while the polymerase stabilizes the NHCP and maintains its ability to stimulate DNA transcription. The NHCP increases the affinity of RNA polymerase to DNA. Upon its addition, longer transcripts are obtained when a zein gene is used as a template for in vitro transcription. The RNA polymerase-NHCP complex formed has greater affinity to DNA than free enzyme. This seems to be due to enhanced sensitivity of bound enzyme to signals encoded in DNA sequences.

Chromatography, Affinity↗

Characterization and sequence analysis of a developmentally regulated putative cell wall protein gene isolated from soybean.

A cDNA clone, pTU04, which hybridizes to two different sizes of mRNA on Northern blots was isolated from soybean suspension culture cell poly(A) RNA. Northern analysis reveals that meristematic tissue produces a 1050-nucleotide mRNA while quiescent mature cells produce primarily a 1220-nucleotide mRNA homologous to pTU04. The cDNA and its corresponding genomic clone have been partially characterized. The nucleotide sequence of the gene predicts a proline-rich protein, designated SbPRP1, which contains a signal peptide sequence and 43 repeats of a sequence consisting primarily of Pro-Pro-Val-Tyr-Lys (CCA-CCA-GTT-TAC-AAG). From nuclease S1 and hybrid-select translation analyses, the cDNA clone pTU04 appears to represent the mRNA for the mature tissue 1220-nucleotide RNA observed on Northern blots. Although there is no direct proof that the encoded protein is a cell wall protein, it has the properties similar to previously isolated cell wall proteins: 1) it is very basic with a high content of Pro, Tyr, and Lys; 2) it has similar hydropathic properties; and 3) its repeating unit shares sequence homology with that of more highly characterized cell wall proteins, generally termed extensin (Chen, J., and Varner, J. E. (1985) EMBO J. 4, 2145-2151; Smith, J. J., Muldoon, E. P., Willard, J. J., and Lamport, D. T. A. (1986) Phytochemistry 25, 1021-1030.

Amino Acid Sequence↗

Compositae and Frullania phytodermatitis.

Clinical features, botany, phytochemistry, patch testing and ecology of Compositae and Frullania (liverwort) allergic contact phytodermatitis are discussed. Allergic contact dermatitis from Compositae continues to attract world-wide attention owing to spread of noxious weeds in India, Europe, Japan and Australia.

Chrysanthemum cinerariifolium↗