The long and the short of it: a global analysis of hawkmoth pollination niches and interaction networks.

1. Proboscis length has been proposed as a key dimension of plant pollination niches, but this niche space has not previously been explored at regional and global scales for any pollination system. Hawkmoths are ideal organisms for exploring pollinator niches as they are important pollinators in most of the biodiverse regions of the earth and vary greatly in proboscis length, with some species having the longest proboscides of all insects. 2. Using datasets for nine biogeographical regions spanning the Old and New World, we ask whether it is possible to identify distinct hawkmoth pollination niches based on the frequency distribution of proboscis length, and whether these niches are reflected in the depths of flowers that are pollinated by hawkmoths. We also investigate the levels of specialization in hawkmoth pollination systems at the regional and community level using data from interaction network studies. 3. We found that most regional hawkmoth assemblages have bimodal or multimodal distributions of proboscis length, and that these are matched by similar distributions of floral tube lengths. Hawkmoths, particularly those with longer proboscides, are polyphagous and at the network level show foraging specialization equivalent to or less than that of bees and hummingbirds. In the case of plants, shorter-tubed flowers are usually visited by numerous hawkmoth species, while those that are longer-tubed tend to exclude shorter-proboscid hawkmoths and thus become ecologically specialized on longer-proboscid hawkmoth species. Longer-tubed flowers tend to have greater nectar rewards and this promotes short-term constancy by long-proboscid hawkmoths. 4. Our results show that pollinator proboscis length is a key niche axis for plants and can account for patterns of evolution in functional traits such as floral tube length and nectar volume. We also highlight a paradoxical trend for nectar resource niche breadth to increase according to proboscis length of pollinators, while pollinator niche breadth decreases according to the tube length of flowers.

Cytotoxic and Antileishmanial Components from the Bark Extract of Ruyschiaphylladenia from Monteverde, Costa Rica.

The bark of Ruyschiaphylladenia was collected from Monteverde, Costa Rica, and extracted with acetone. Bioactivity-directed chromatographic separation of the crude acetone bark extract of R. phylladenia led to isolation and identification of lupeol, betulinic acid, and isofraxidin. Lupeol and betulinic acid showed in-vitro cytotoxic activity to MCF-7, MDA-MB-231, and 5637 human tumor cell lines. Isofraxidin was not cytotoxic, but did show antileishmanial activity to Leishmania amazonensis promastigotes.

Phytochemical investigations of Lonchocarpus bark extracts from Monteverde, Costa Rica.

The acetone bark extracts of three species of Lonchocarpus from Monteverde, Costa Rica, L. atropurpureus, L. oliganthus, and L. monteviridis, were screened for antibacterial, cytotoxic, and antioxidant activities. L. orotinus extract was antibacterial against Bacillus cereus (MIC = 39 microg/mL), while L. monteviridis exhibited the most antioxidant activity. None of the Lonchocarpus extracts showed cytotoxic activity against MCF-7 cells. Fatty acids and atraric acid were isolated and purified from L. atropurpureus bark, fatty acids and loliolide from L. oliganthus bark, and leonuriside A and beta-D-glucopyranos-1-yl N-methylpyrrole-2-carboxylate from L. monteviridis bark. Atraric acid showed cytotoxic and antimicrobial activities.

A phytochemical investigation of Zanthoxylum setulosum.

The crude bark extract of Zanthoxylum setulosum from Monteverde, Costa Rica was notably cytotoxic (100% kill at 100 microg/mL) to MCF-7, MDA-MB-231, and MDA-MB-468 cells in vitro. Phytochemical studies of the bark extract revealed the triterpenoid lupeol, the lignan sesamin, the sesquiterpene sesquichamaenol, and the xanthone lichexanthone. This is the first report of the isolation of sesquichamaenol and lichexanthone from the bark extract of Z. setulosum. All structures were determined using NMR spectroscopic techniques (1H NMR and 13 degrees C NMR) and GC-MS and by comparison with literature data. Lupeol proved to be the cytotoxic component of Z. setulosum bark.

Prenylated isoflavonoids from Rhynchosia edulis.

Four new prenylated isoflavones, rhynedulins A-C (1-3) and rhynedulinal (4), were isolated by bioassay-guided fractionation of the dichloromethane bark extract of Rhynchosia edulis. Five previously described compounds, scandenal, ulexin B, cajanone, cajanin, and cyclochandalone, were also isolated. These isoflavonoids showed weak inhibitory activity towards rhodesain, the major cathepsin-L like protease in Trypanosoma brucei. They also have weak antiproliferative activity towards MCF-7 cells.

Phytochemical investigation of Verbesina turbacensis Kunth: trypanosome cysteine protease inhibition by (-)-bornyl esters.

The bark and leaf essential oils of Verbesina turbacensis were obtained by hydrodistillation and analyzed by GC-MS. The bark oil of the plant was composed mainly of monoterpene hydrocarbons (83.5-90.4%), predominately alpha-pinene, while the leaf oil was composed mainly of sesquiterpene hydrocarbons, dominated by germacrene-D (29.1-36.9%), and delta-elemene (21.7-22.1%). Three bornyl hydroxycinnamic esters isolated from the acetone bark extract were found to inhibit the cysteine protease, rhodesain. Molecular docking analysis to probe the inhibitory interactions of the esters was also carried out.

Chemical composition of the leaf essential oil of Casimiroa edulis La Llave & Lex. (Rutaceae) from Monteverde, Costa Rica.

The leaf essential oil of Casimiroa edulis (Rutaceae), collected from Monteverde, Costa Rica, has been obtained by hydrodistillation and analyzed by GC-MS. The leaf oil was dominated by sesquiterpene hydrocarbons, predominately germacrene D (16-22%) and (E)-caryophyllene (16-17%), consistent with the traditional use of this plant as a sedative, sleep inducer and hypotensive.

Essential oil compositions of three Lantana species from Monteverde, Costa Rica.

The leaf essential oils of three species of Lantana from Monteverde, Costa Rica (L. camara, L. velutina, and L. hirta) were obtained by hydrodistillation and the chemical compositions determined by GC-MS analysis. The principal components of L. velutina were limonene (21.4%), (E)-caryophyllene (23.4%) and bicyclogermacrene (8.2%). The leaf oil composition of L. hirta was relatively simple, containing mostly 1-octen-3-ol (64.6%), germacrene D (24.5%), and (E)-caryophyllene (10.9%). Two different samples of L. camara, however, yielded vastly different leaf oil compositions; one was dominated by sesquiterpenes, (E)-caryophyllene (30.3%), gamma-muurolene (27.2%), bicyclogermacrene (24.4%) and beta-elemene (14.2%); the second sample, on the other hand, was composed largely of fatty acid-derivatives, (Z)-3-hexenol and 1-octen-3-ol. The very different compositions for L. camara are consistent with the wide diversity of chemical compositions observed in previous reports for this species.

Essential oil compositions and cytotoxic activities of Dendropanax capillaris, Oreopanax nubigenus, and Schefflera rodrigueziana from Monteverde, Costa Rica.

The leaf essential oils of Dendropanax capillaris, Oreopanax nubigenus and Schefflera rodrigueziana (Araliaceae) were isolated by hydrodistillation and analyzed by GC-MS. The leaf oil of Dendropanax capillaris was composed of only four compounds, beta-pinene (25.3%), 6-3-carene (44.7%), daucene (17.1%), and dauca-5,8-diene (12.9%). Oreopanax nubigenus leaf oil was dominated by the sesquiterpene hydrocarbons germacrene D (70.1%) and beta-caryophyllene (11.8%), while Schefflera rodrigueziana leaf oil was made up entirely of sesquiterpene hydrocarbons, mostly germacrene D (27.6%), beta-cubebene (27.2%), beta-caryophyllene (12.2%), beta-cubebene (11.1%), and alpha-copaene (10.8%). Both O. nubigenus and S. rodrigueziana leaf oils showed notable in-vitro cytotoxicity on MDA-MB-231 cells, which may be attributable to the relatively high concentrations of germacrene D and beta-caryophyllene in those oils.

Leaf essential oil composition of three species of Myrcianthes from Monteverde, Costa Rica.

To examine the chemical diversity of essential oils from Myrcianthes species (Myrtaceae) as well as potential chemotaxonomic relationships between them, the leaf essential oils of M. fragrans (Sw.) McVaugh, M. rhopaloides (Kunth) McVaugh, and an undescribed species, Myrcianthes 'black fruit', from Monteverde, Costa Rica, were isolated by hydrodistillation and analyzed by GC/MS. The most abundant components of the essential oil of M. fragrans were 1,3,5-trimethoxybenzene (15.7%), (Z)-hex-3-en-1-ol (10.0%), alpha-cadinol (10.4%), eudesma-4(15),7-dien-1beta-ol (9.0%), caryophyllene oxide (7.8%), and spathulenol (7.5%). The leaf oils of two different samples of Myrcianthes rhopaloides were quantitatively different with one sample composed mostly of linalool (17.7%), alpha-cadinol (14.4%), spathulenol (11.1%), tau-cadinol (9.6%), and 1-epicubenol (6.9%), and the other was made up largely of (E)-hex-2-enal (46.1%), 1,8-cineole (12.5%), linalool (9.1%), alpha-cadinol (6.7%), and alpha-terpineol (4.4%). The major components in the leaf essential oil of Myrcianthes 'black fruit' were 1,8-cineole (38.3%), alpha-terpineol (21.2%), heptan-2-ol (15.5%), terpinen-4-ol (4.2%), and beta-pinene (3.8%). The leaf oil compositions of Myrcianthes in this study are very different from leaf oils from other members of Myrcianthes reported in the literature. A cluster analysis reveals large chemical variation not only between members of the genus, but also between samples of the same species.

Bioactivity and chemical composition of the leaf essential oils of Zanthoxylum rhoifolium and Zanthoxylum setulosum from Monteverde, Costa Rica.

The leaf essential oils of Zanthoxylum rhoifolium and Zanthoxylum setulosum (Rutaceae) from Monteverde, Costa Rica have been obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The principal constituents of Z. rhoifolium leaf oil were germacrene D (14.6%), limonene (12.5%), trans-2-hexenal (11.3%), beta-elemene (9.2%), 2-undecanone (9.2%), myrcene (7.9%), bicyclogermacrene (7.5%), and germacrene A (5.2%). The leaf oil of Z. setulosum was composed largely of beta-phellandrene (37.5%), beta-caryophyllene (13.7%), alpha-pinene (11.9%), germacrene D (10.9%), myrcene (5.9%), and nerolidol (5.4%). The essential oils were screened for in-vitro cytotoxic activity against Hep G2, MCF-7, and PC-3 human tumor cell lines; antibacterial activity against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli; and for Artemia salina (brine shrimp) lethality. Neither Z. rhoifolium nor Z. setulosum leaf oils exhibited cytotoxicity or antibacterial activity. Both oils showed activity against A. salina.

Isolation of cupanioside, a novel cytotoxic and antibacterial long-chain fatty alcohol glycoside from the bark of Cupania glabra.

The crude dichloromethane extract from the stem bark of Cupania glabra (Sapindaceae), showed in vitro cytotoxic activity against Hep G2, MDA-MB-231, Hs 578T, MCF-7, and PC-3 cells, and antibacterial activity against Bacillus cereus, Staphylococcus aureus, and Escherichia coli. Bioactivity-directed fractionation led to isolation of the new 1-O-[2'',3'',4''-tri-O-acetyl-alpha-L-rhamnopyranosyl-(1-->2)-beta- D-glucopyranosyl]-hexadecanol (cupanioside) as the cytotoxic agent. The structure was elucidated by analysis of 2D-NMR spectra.

Leaf essential oil composition of five Zanthoxylum species from Monteverde, Costa Rica.

The leaf essential oils from five species of Zanthoxylum (Rutaceae) from Monteverde, Costa Rica, have been obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The species examined include Z. fagara, Z. acuminatum, Z. melanostictum, Z. monophyllum, and an undescribed species. The most abundant classes of compounds found in Zanthoxylum leaf oils are acyclic and menthane monoterpenoids as well as simple alcohols, aldehydes, and ketones. In terms of molecular diversity, menthane and acyclic monoterpenoids, cadinane and mesocyclic sesquiterpenoids, and simple alcohols, aldehydes, and ketones dominate the essential oils of Zanthoxylum species. Monoterpenoids make up the majority of the mass of the leaf oils of Z. monophyllum, Z. acuminatum, Z. fagara, and Zanthoxylum sp. nov. Linalool, 4-terpineol, alpha-terpineol, and trans-2-hexenol, are found in all of the Zanthoxylum species examined in this study.

Phytomedicinal potential of tropical cloudforest plants from Monteverde, Costa Rica

A pharmacological survey of plants from Monteverde, Costa Rica, including 165 species representing 61 families has been carried out. Crude plant extracts have been tested for in-vitro bactericidal and fungicidal activity as well as cytotoxic and anti-herpes activity. Of these, 123 extracts exhibited notable cytotoxicity, 62 showed antibacterial activity, 4 showed antifungal activity, and 8 showed promising antiviral activity. Thus, 101 of the plant species examined in this work, or 62, showed marked bioactivity in one or more bioassays. These results underscore the phytomedicinal potential of Neotropical cloud forests.

Phytomedicinal potential of tropical cloudforest plants from Monteverde, Costa Rica.

A pharmacological survey of plants from Monteverde, Costa Rica, including 165 species representing 61 families has been carried out. Crude plant extracts have been tested for in-vitro bactericidal and fungicidal activity as well as cytotoxic and anti-herpes activity. Of these, 123 extracts exhibited notable cytotoxicity, 62 showed antibacterial activity, 4 showed antifungal activity, and 8 showed promising antiviral activity. Thus, 101 of the plant species examined in this work, or 62%, showed marked bioactivity in one or more bioassays. These results underscore the phytomedicinal potential of Neotropical cloud forests.