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Monique S J Simmonds

Publications and source records attributed to Monique S J Simmonds.

At least 19 recordsLinked to original sources
PubMed2006

Insect-antifeedant and antibacterial activity of diterpenoids from species of Plectranthus.

Bio-assay guided fractionation of an acetone extract of leaf material from Plectranthus saccatus Benth. resulted in the isolation of a beyerane diterpenoid. This compound, characterised by spectroscopic methods as ent-3beta-(3-methyl-2-butenoyl)oxy-15-beyeren-19-oic acid, showed insect antifeedant activity against Spodoptera littoralis. Known quinonoid abietane diterpenoids obtained from new sources included a mixture of the (4R,19R) and (4R,19S) diastereoisomers of coleon A from P. aff. puberulentus J.K. Morton, coleon A lactone from P. puberulentus J.K. Morton, and coleon U and coleon U quinone from P. forsteri 'Marginatus' Benth. These compounds, and the crude acetone extracts from the leaf surfaces of 11 species of Plectranthus, were tested for antifeedant activity against S. littoralis, antibacterial activity against Bacillus subtilis and Pseudomonas syringae and antifungal activity against Cladosporium herbarum. The coleon A mixture showed potent antifeedant activity against S. littoralis, whereas coleon U showed the greatest antimicrobial activity.

Abietanes↗
PubMed2006

Botanical nomenclature in pharmacovigilance and a recommendation for standardisation.

Nomenclature of plants in pharmacology can be presented by pharmaceutical names or scientific names in the form of Linnaean binomials. In this paper, positive and negative aspects of both systems are discussed in the context of the scientific nomenclatural framework and the systems' practical applicability. The Uppsala Monitoring Centre (UMC) runs the WHO Programme for International Drug Monitoring and is responsible for the WHO Adverse Drug Reaction (ADR) database that currently contains 3.6 million records. In order for the UMC to monitor pharmacovigilance through ADRs to herbal medicine products the following nomenclatural criteria are important: (i) the name should indicate only one species of plant; (ii) the source for this name must be authoritative; (iii) the name should indicate which part of the plant is used. Based on these criteria, the UMC investigated four options: (i) adopt main names used in recognised (inter-) national pharmacopoeias or authoritative publications; (ii) adopt option 1, but cite the publication for all names in abbreviated form; (iii) three-part pharmaceutical names consisting of Latinised part name plus Latinised genus name, plus Latinised specific epithet; (iv) scientific binomial names, optionally with author and plant part used. The UMC has chosen the latter option and will at its adoption utilise the scientific botanical nomenclature as defined by the International Code of Botanical Nomenclature. This decision satisfies all criteria set by the UMC and renders the necessity of creating a new system or upgrading an old inconsistent system obsolete. The UMC has also issued an extensive synonymy checklist of vernacular, pharmaceutical and scientific names for the herbals in the WHO ADR database. We strongly recommend the adoption of scientific names to denote plant ingredients in medicine.

Humans↗
PubMed2005

Data-directed scan sequence for the general assignment of C-glycosylflavone O-glycosides in plant extracts by liquid chromatography-ion trap mass spectrometry.

An ion trap LC-MS/MS method is described for the analysis of C-glycosylflavone O-glycosides in crude methanolic extracts of plants. The method employs survey scans with and without the application of up-front collision induced dissociation (CID) to generate diagnostic ions for data-directed MS/MS. The spectra acquired allow assignment of the C-linked sugar to either the C-6 or C-8 position of the aglycone and provide data on the molecular mass of the compound, the number and type of O-linked sugars and the molecular mass of the flavone aglycone. These data for the majority of C-glycosylflavone O-glycosides in an extract are obtained automatically in one LC-MS/MS analysis without manual pre-programming. Key to the assignment of the C-6 or C-8 site of C-glycosylation is the generation, by up-front CID, of the (0,1)X+ product ion formed by internal cleavage of the C-linked sugar. MS/MS of this ion is found to have diagnostic value in addition to the (0,2)X+ product ion described by other authors. Ion trap MS/MS spectra of [M+H]+ of the 6,8-di-C-glycosylflavones schaftoside and isoschaftoside show an additional and previously unreported diagnostic product ion that is useful in determining the type of sugar at the C-6 position. The product ion spectra of protonated kaempferol 3-O-glucosylrhamnosides show similarities to the spectra of C-glycosylflavone O-glycosides; this is a potential source of confusion if the analysis of such glycosides is limited solely to MS/MS of [M+H]+.

Chromatography, Liquid↗
PubMed2005

Plectranthus: a review of ethnobotanical uses.

Plectranthus is a large and widespread genus with a diversity of ethnobotanical uses. The genus is plagued with numerous nomenclatural disharmonies that make it difficult to collate accurate data on the uses. The aim of this review is to gather together all ethnobotanical information on Plectranthus and to map the data onto the most up-to-date phylogenetic classification in order to see if there are similar uses among related species and hence provide a framework for the prediction and exploration of new uses of species. The uses of 62 species of Plectranthus were mapped onto a current phylogeny based on DNA sequence data. The phylogeny reveals two major Clades, 1 and 2. The members of Clade 1 (corresponding to the formally recognized genus Coleus) were richer in number and diversity of uses than members of Clade 2 (comprising the remaining species of Plectranthus). The high incidence of synonymy can lead to problems in uncovering a species' ethnobotanical profile. About 30% of all citations of Plectranthus use a synonym and most of the synonyms are attributed to 10 of the most used species, 9 of which are in Clade 1. Members of the 'Coleus' Clade are the most studied group both taxonomically and economically. The higher incidence of study may be as a result of the higher diversity of uses and the fact that species in Clade 1, such as Plectranthus barbatus, Plectranthus amboinicus and Plectranthus mollis, are geographically more widespread than those in Clade 2. Plectranthus species in Clade 1 are frequently used as medicines and are used to treat a range of ailments, particularly digestive, skin, infective and respiratory problems. Plectranthus used as foods, flavours, fodder and materials are also mostly found in Clade 1. Monoterpenoids, sesquiterpenoids, diterpenoids and phenolics have been reported in species of Plectranthus. The abietane diterpenoids are the most diverse of the diterpenoids isolated from species of Plectranthus. The labdane diterpenoid, forskolin, occurs in Plectranthus barbatus and could explain some of the traditional uses of this species. This review highlights the fact that not enough is known about the chemistry of other species of Plectranthus to explain their traditional uses.

Animals↗
PubMed2005

Ethnobotanical study of some Ghanaian anti-malarial plants.

An ethnobotanical study was conducted in the Wechiau Community Hippopotamus Sanctuary area in Ghana, through interviews and quadrate studies, to investigate the range and abundance of species used in the treatment of malaria. Forty-one species belonging to 17 families were encountered during the study. Of the 17 families studied Leguminosae and Anacardiaceae predominated in terms of number of species used to treat malaria. Eight plant species namely, Afraegle paniculata (Rutaceae), Haematostaphis barteri (Anacardiaceae), Indigo era pulchra (Leguminosae), Monanthotaxis sp. (Annonaceae), Ozoroa insignis (Anacardiaceae), Strychnos innocua (Loganiaceae), Strychnos spinosa (Loganiaceae) and Xeroderris stuhlmannii (Leguminosae) have not previously been documented for the treatment of malaria in Ghana. The results are discussed and recommendations made for future research to support the conservation and sustainable harvesting of the species reported to have medicinal properties.

Antimalarials↗
PubMed2005

Identification and antioxidant potential of flavonoids and low molecular weight phenols in olive cultivar chemlali growing in Tunisia.

Increasing interest in phenolic compounds in olives is due to their antioxidant and health-enhancing properties. In this study the phenolics in fruits of the Tunisian olive cultivar Chemlali were extracted by methanol-water and fractionated using Sephadex LH-20 column chromatography. The identification of phenolic monomers and flavonoids was based on separation by high-performance liquid chromatography equipped with a diode array detector followed by liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry analysis. Oleuropein, a secoiridoid glycoside esterified with a phenolic acid, was the major compound. Eight phenolic monomers and 12 flavonoids were also identified in Chemlali olives. Five flavonoids were isolated and purified using Sephadex LH-20 column chromatography and preparative paper chromatography. The antioxidant activity of the extract and the purified compounds was evaluated by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl and by using the beta-carotene-linoleate model assay. Acid hydrolysis of the extract enhanced its antioxidant activity. Hydroxytyrosol and quercetin showed antioxidant activities similar to that of 2,6-di-tert-butyl-4-methylphenol. A hydroxyl group at the ortho position at 3' on the B ring of the flavonoid nucleus could contribute to the antioxidant activity of the flavonoids.

Antioxidants↗
PubMed2004

Extremely potent antifeedant neo-clerodane derivatives of scutecyprol A.

Two known neo-clerodane diterpenoids, scutecyprol A (1) and scutalbin C (2), have been isolated from the acetone extract of the aerial parts of Scutellaria sieberi. The antifeedant activity of scutecyprol A (1), of its 15-oxo derivative (3), and of several halohydrins (4-9), synthesized starting from compounds 1 and 3, against Spodoptera littoralis have been determined and structure-antifeedant relationships are discussed.

Animals↗
PubMed2004

Effect of different photoperiods on the growth, infectivity and colonization of Trinidadian strains of Paecilomyces fumosoroseus on the greenhouse whitefly, Trialeurodes vaporariorum, using a glass slide bioassay.

Growth, infectivity and colonization rates for blastospores and conidia of Trinidadian strains T, T10, and T11 of Paecilomyces fumosoroseus (Wize) Brown and Smith were assessed for activity against late fourth-instar nymphs of Trialeurodes vaporariorum (Westwood) (Homoptera:Aleyrodidae) under two different photoperiods (24 and 16 hour photophase). A glass-slide bioassay and a fungal development index, modified for both blastospores and conidia, were used to compare the development rates of the fungal strains on the insect hosts. Fewer adult whiteflies emerged from nymphs treated with blastospores and reared under a 16:8 hour light:dark photoperiod than a 24:0 hour photoperiod. Eclosion times of whitefly adults that emerged from nymphs treated with the different strains of conidia were similar over the 8 day experimental period at both light regimes. The percent eclosion of adult whiteflies seems to be directly correlated with the speed of infection of the blastospore or conidial treatment and the photoperiod regime. The longer photophase had a significant positive effect on development index for blastospores; however, a lesser effect was observed for the conidia at either light regime. Blastospore strain T11 offered the most potential of the three Trinidadian strains against T. vaporariorum fourth-instar nymphs, especially under constant light. The glass-slide bioassay was successfully used to compare both blastospores and conidia of P. fumosoroseus. It can be used to determine the pathogenicity and the efficacy of various fungal preparations against aleyrodid pests.

Animals↗
PubMed2004

Evaluation of the quality of sandalwood essential oils by gas chromatography-mass spectrometry.

Trade and historic oils from 'sandalwoods', labelled as Amyris balsamifera, Eremophila mitchelli, Fusanus acuminatus (= Santalum acuminatum), Santalum album, S. austrocaledonicum, S. latifolium, S. spicatum and S. yasi, were assessed using gas chromatography-mass spectrometry (GC-MS). Using GC-MS, none of the oils assessed complied with the internationally recognised standard of a 90% santalol content, and only about half of the trade sandalwood oils met with recent International Organisation for Standardisation standards. The majority of trade oils, reportedly from S. album, contained approximately 50-70% santalols (Z-alpha and Z-beta). Thus, the internationally recognised specification (90% santalols) for S. album requires re-evaluation by more efficient analysis methods. In view of the issues associated with the quality of sandalwood oils being traded, specifications of > or = 43% Z-alpha-santalol and > or = 18% Z-beta-santalol for S. album oil estimated by GC-MS are suggested. GC-MS are recommended as it assists with authentication and quality control issues associated with sandalwood oils.

Gas Chromatography-Mass Spectrometry↗
PubMed2004

Comparison of anti-feedant and insecticidal activity of nimbin and salannin photo-oxidation products with neem (Azadirachta indica) limonoids.

Photo-oxidation of the neem limonoids nimbin and salannin with UV light in the presence of oxygen gives two isomeric lactone products per limonoid, nimbinolide and isonimbinolide, and salanninolide and isosalanninolide, respectively. When compared in insect tests with the important limonoids of neem seeds, azadirachtin, nimbin and salannin, isonimbinolide and isosalanninolide show activity greater than that of nimbin or salannin and in some respects show activity approaching that of azadirachtin. The photo-oxidation products were tested for anti-feedant activity and toxicity against larvae of three species of Lepidoptera, Spodoptera littoralis (Boisd), Spodoptera frugiperda (FE Smith) and Helicoverpa armigera (Hübner) and nymphs of the locusts Schistocerca gregaria (Forskål) and Locusta migratoria (L).

Animals↗
PubMed2004

Effects of plant-derived compounds on larvae of a blow fly species that causes secondary myiases: laboratory studies.

No-choice and binary-choice bioassays were used to test the effect of a range of plant-derived insecticides on the behaviour of larvae of the black blow fly Phormia regina (Meigen). Azadirachtin (100 and 10 ppm), pyrethrum extract (10 ppm) and the naphthoquinone BTG 505 (1000 ppm) acted as deterrents for P. regina larvae. The mortality of larvae was reduced in instances where they moved away from a treated diet. Larvae given a choice were heavier, when compared with larvae reared exclusively on diets containing either azadirachtin (100 or 10 ppm) or the naphthoquinones, BTG 504 (1000 ppm) or BTG 505 (1000 ppm). The deterrent effect of azadirachtin, pyrethrum and the naphthoquinone BTG 505 together with their larvicidal activity, could be utilized in prophylaxis against myiasis infections due to larvae of Phormia regina.

Animals↗
PubMed2004

Antibacterial activity of the Chinese traditional medicine, Zi Hua Di Ding.

The antibacterial activity of extracts from species of plants used in the Chinese medicine, Zi Hua Di Ding (Viola yedoensis, V. prionantha, Corydalis bungeana and Gueldenstaedtia verna), was tested against Bacillus subtilis and Pseudomonas syringae using a bioautographic assay. The petroleum ether and ethyl acetate extracts of all four species of plants showed activity against both species of bacteria, whereas the methanol and aqueous methanol extracts were inactive. Three fractions from the petroleum ether extracts of V. yedoensis, V. prionantha and C. bungeana showed activity against B. subtilis at 6.25 microg/mL. Preliminary analysis of these active fractions indicates that they contain long chain carboxylic acids.

Anti-Bacterial Agents↗
PubMed2004

Metabolomic analysis of saponins in crude extracts of Quillaja saponaria by liquid chromatography/mass spectrometry for product authentication.

Analysis of 50% aqueous methanolic extracts of bark of Quillaja saponaria Molina (quillaja) by liquid chromatography/mass spectrometry (LC/MS), using negative ion electrospray, revealed over 100 saponins. The majority could be assigned to known structures or generalised variations of these from the product ion spectra obtained by serial mass spectrometry in a quadrupole ion trap mass spectrometer. Ten saponins contained a fatty acid domain terminated with both a pentose and deoxyhexose unit, a feature thus far only reported in QS-III. Twenty saponins were based on a hydroxylated derivative of quillaic acid, whereas only six 22beta-hydroxyquillaic acid saponins have been described. The occurrence of pairs of saponins differing only by the presence of a rhamnose or xylose unit in the C-3-substituted saccharide was readily observed in two-dimensional mass maps, and these showed the presence of the unreported 'rhamnose partner' of QS-III. However, one sample labelled as Q. saponaria appeared to lack all saponins containing rhamnose in the C-3 saccharide. Methods to authenticate saponin extracts of quillaja by LC/MS are suggested based on the general metabolomic profile, the occurrence of specific major saponins covering known structural variations, or the presence of saponins containing the unusual fatty acid domain, revealed by neutral loss analysis.

Chromatography, High Pressure Liquid↗
PubMed2004

Flavonoid glycosides and isoquinolinone alkaloids from Corydalis bungeana.

Two flavonol O-glycosides identified as the 3-O-alpha-arabinopyranosyl(1'''-->6'')-beta-glucopyranoside 7-O-beta-glucopyranosides of kaempferol and quercetin were isolated from the whole plant of Corydalis bungeana Turcz. together with eight known flavonol O-glycosides. Two isoquinolinone alkaloids were also obtained from the same source, including the new derivative, 6,7-methylenedioxy-2-(6-acetyl-2,3-methylenedioxybenzyl)-1(2H)-isoquinolinone. The structures were determined by spectroscopic methods (NMR and high-resolution MS).

Alkaloids↗
PubMed2004

Phylogeny and evolution of basils and allies (Ocimeae, Labiatae) based on three plastid DNA regions.

A phylogeny of basils and allies (Lamiaceae, tribe Ocimeae) based on sequences of the trnL intron, trnL-trnF intergene spacer and rps 16 intron of the plastid genome is presented. Several methods were used to reconstruct phylogenies and to assess statistical support for clades: maximum parsimony with equally and successively weighted characters, bootstrap resampling, and Bayesian inference. The phylogeny is used to investigate the distribution of morphological, pericarp anatomy, chemical, and pollen characters as well as the geographical distribution of the clades. Tribe Ocimeae is monophyletic and easily diagnosable with morphological synapomorphies. There are monophyletic clades within Ocimeae that broadly correspond to currently recognised subtribes: Lavandulinae, Hyptidinae, Ociminae, and Plectranthinae. Only Lavandulinae has clear non-molecular synapomorphies. Several currently recognised genera are not monophyletic. Floral morphology consistent with sternotribic pollination is most common in Ocimeae, but there are independent departures from this model. Buzz pollination is likely in some species, the only postulated occurrence of this within Lamiaceae. Quinone diterpenoids and flavones in the leaf exudates differ in their distributions across the phylogeny and this could contribute to differences in the recorded medicinal as well as pesticidal uses of the species in the different clades. Mapping geographic distribution on to an ultrametric phylogenetic tree produced using non-parametric rate smoothing supports an Asiatic origin for Ocimeae. There are several secondary occurrences in Asia arising from the African Ociminae and Plectranthinae clades. Colonisation of Madagascar occurred at least five times, and New World colonisation occurred at least three times.

Bayes Theorem↗
PubMed2004

Neoclerodanes from Teucrium orientale.

Two new neoclerodane diterpenoids, 6-deacetyl-teucrolivin A (5) and 8beta-hydroxy-teucrolivin B (6), were isolated from the aerial parts of Teucrium orientale, along with four already known neoclerodane diterpenoids, teucrolivin A (1), teucrolivin B (2), teucrolivin C (3) and teucrolivin H (4), previously isolated from Teucrium oliverianum. Their structures were elucidated on the basis of spectroscopic evidence and chemical transformations. Compounds 1-3 were assayed for antifeedant activity against Spodoptera littoralis, S. frugiperda and Heliocoverpa armigera. Teucrolivin A was the most potent of the three compounds tested.

Animals↗