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The essential oil obtained from the dry leaves of Gynoxys szyszylowiczii Hieron. was described in this study for the first time. The chemical analysis, conducted on two stationary phases of different polarity, permitted to identify sixty-four compounds, that were quantified with at least one column. The main components, on a non-polar and polar stationary phase respectively, were germacrene D (21.6-19.2%), α-pinene (4.4-4.9%), n-tricosane (4.3% on both columns), (E)-ß-caryophyllene (3.3-4.3%), 1-docosene (3.2-2.8%), α-cadinol (2.8-3.1%), and cis-ß-guaiene (2.6-3.0%). This investigation was complemented by the enantioselective analysis of some major chiral compounds, carried out on two chiral selectors based on ß-cyclodextrines. As a result, (S)-( +)-α-phellandrene, (S)-( +)-ß-phellandrene, and (1S,2R,6R,7R,8R)-( +)-α-copaene appeared enantiomerically pure, whereas α-pinene, ß-pinene, terpinen-4-ol, and germacrene D were detected as scalemic mixtures. Finally, linalool was practically racemic. The distillation yield, analytically calculated by weight of dry plant material, was 0.03%.
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The present study belonged to an unfunded project, dealing on the systematic description of unprecedented essential oils (EOs), distilled from 12 species of genus Gynoxys Cuatrec. In this very case, the aim was the first chemical and enantiomeric analyses of two volatile fractions, obtained from the leaves of Gynoxys cuicochensis Cuatrec. and Gynoxys sancti-antonii Cuatrec. These EOs were analyzed by GC-MS (qualitatively) and GC-FID (quantitatively), detecting 89 and 60 components from G. cuicochensis and G. sancti-antonii, respectively. Major components for G. cuicochensis EO, on a nonpolar and polar stationary phase, were α-pinene (29.4-29.6%), p-vinylguaiacol (3.3-3.6%), and germacrene D (20.8-19.9%). In G. sancti-antonii EO, the main compounds were α-pinene (3.0-2.9%), ß-pinene (12.9-12.1%), γ-curcumene (19.7-18.3%), germacrene D (9.0% on the polar phase), ar-curcumene (5.3% on the polar phase), δ-cadinene (4.1-4.6%), α-muurolol (3.3-2.4%), α-cadinol (3.0% on both columns), and an undetermined compound, of molecular weight 220. In addition to chemical composition, the enantioselective analysis of the main chiral compounds was carried out on two different chiral selectors. In G. cuicochensis EO, (1R,5R)-(+)-α-pinene, (S)-(+)-ß-phellandrene, (R)-(-)-piperitone, and (S)-(-)-germacrene D were enantiomerically pure, whereas ß-pinene, sabinene, α-phellandrene, limonene, linalool, and terpinen-4-ol were observed as scalemic mixtures. On the other hand, in G. sancti-antonii EO, the pure enantiomers were (1S,5S)-(-)-α-pinene, (1R,5R)-(+)-sabinene, (R)-(-)-ß-phellandrene, (S)-(-)-limonene, (1S,2R,6R,7R,8R)-(+)-α-copaene, (R)-(-)-terpinen-4-ol, and (S)-(-)-germacrene D, whereas ß-pinene, linalool, and α-terpineol were present as scalemic mixtures. The principal component analysis demonstrated that G. cuicochensis volatile fraction was quite similar to many of the other EOs of the same genus, whereas G. sancti-antonii produced the most dissimilar EO. Furthermore, the enantioselective analyses showed the usual variable enantiomeric distribution, with a greater presence of enantiomerically pure compounds in G. sancti-antonii EO.
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In the present study, the essential oil from dry leaves of Steiractinia sodiroi (Hieron.) S.F. Blake is described for the first time. The plant material, collected in the Province of Loja (Ecuador), was analytically steam-distilled in a Marcusson-type apparatus, affording an essential oil with a 0.2 ± 0.12% yield. The volatile fraction was submitted to GC-MS and GC-FID analyses, on two stationary phases of different polarity. A total of sixty-seven compounds, corresponding to 95.6-91.2% by weight of the whole oil mass, on the two columns respectively, were detected and quantified with at least one column. The quantification was carried out calculating the relative response factors of each constituent according to their combustion enthalpy. The major components were limonene (25.6-24.9%), sabinene (11.7-12.4%), germacrene D (7.7-7.0%), α-pinene (7.8-6.9%), δ-cadinene (7.3-7.0%), (E)-ß-caryophyllene (4.8-4.5%), and bicyclogermacrene (3.6-3.0%). The chemical composition was complemented with the enantioselective analysis of some major chiral compounds, conducted by means of two ß-cyclodextrin-based capillary columns. Three constituents, (S)-(+)-α-phellandrene, (R)-(-)-1-octen-3-ol, and (S)-(-)-limonene were enantiomerically pure, whereas (1R,5R)-(+)-ß-pinene, (1S,5S)-(-)-sabinene, (R)-(-)-terpinen-4-ol, (R)-(+)-α-terpineol, and (R)-(+)-germacrene D presented an enantiomeric excess. Finally, α-pinene was present as a racemic mixture.
Asunto(s)
Asteraceae , Aceites Volátiles , Aceites Volátiles/química , Ecuador , Estereoisomerismo , LimonenoRESUMEN
The leaves of Nectandra laurel Klotzsch ex Nees, belonging to the family, Lauraceae, were collected in the province of Loja (Ecuador), dried, and analytically steam-distilled. An unprecedented essential oil was obtained, with a 0.03% yield by weight of dry plant material. The volatile fraction was submitted to qualitative (GC-MS) and quantitative (GC-FID) chemical analysis, on two orthogonal stationary phases. Seventy-eight compounds were detected and quantified on at least one column. The essential oil was dominated by sesquiterpene hydrocarbons (53.0-53.8% on the non-polar and polar stationary phase, respectively), followed by oxygenated sesquiterpenoids (18.9-19.0%). A third group was constituted by metabolites of other origins, mainly aliphatic compounds, apparently derived from the acetate pathway (11.7-8.5%). The major components of the EO (≥3.0% with at least one column) were δ-selinene (30.5-28.8%), δ-cadinene (5.4-6.4%), epi-α-cadinol (4.9-5.2%), an undetermined compound with a molecular weight of 204 (3.4-4.2%), α-pinene (3.3-2.9%), and α-cadinol (2.9-3.0%). Finally, the essential oil was submitted to enantioselective analysis, on two ß-cyclodextrin-based chiral selectors, determining the enantiomeric distribution of seven chiral terpenes. Among them, (1R,5R)-(+)-α-pinene, (1R,5R)-(+)-ß-pinene, and (R)-(-)-α-phellandrene were enantiomerically pure, whereas camphene, borneol, α-copaene, and α-terpineol were present as scalemic mixtures.
RESUMEN
The fresh leaves of Gynoxys laurifolia (Kunth) Cass. (Asteraceae), collected in the province of Loja (Ecuador), were submitted to steam distillation, producing an essential oil with a yield of 0.02% by weight. This volatile fraction, described here for the first time, was submitted to qualitative (GC-MS) and quantitative (GC-FID) chemical analyses, on two orthogonal columns (non-polar and polar stationary phase). A total of 90 components, corresponding to 95.9-95.0% by weight on the non-polar and polar stationary phase, respectively, were detected and quantified with at least one column. Major constituents (≥3%) were: germacrene D (18.9-18.0%), (E)-ß-caryophyllene (13.2-15.0%), α-pinene (11.0-10.3%), ß-pinene (4.5-4.4%), ß-phellandrene (4.0-3.0%), bicyclogermacrene (4.0-3.0%), and bakkenolide A (3.2-3.4%). This essential oil was dominated by sesquiterpene hydrocarbons (about 45%), followed by monoterpene hydrocarbons (about 25-30%). This research was complemented with the enantioselective analysis of some common chiral terpenes, carried out through 2,3-diethyl-6-tert-butyldimethylsilyl-ß-cyclodextrin and 2,3-diacetyl-6-tert-butyldimethylsilyl-ß-cyclodextrin as stationary phase chiral selectors. As a result, (1S,5S)-(-)-ß-pinene, (R)-(-)-α-phellandrene, (R)-(-)-ß-phellandrene, (S)-(-)-limonene, (S)-(+)-linalyl acetate, and (S)-(-)-germacrene D were observed as enantiomerically pure compounds, whereas α-pinene, linalool, terpinene-4-ol, and α-terpineol were present as scalemic mixtures. Finally, sabinene was practically racemic. Due to plant wildness and the relatively low distillation yield, no industrial applications can be identified, in the first instance for this essential oil. The focus of the present study is therefore academic.
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The present study describes the chemical and enantiomeric composition of a new essential oil, distilled from the dry leaves of Gynoxys buxifolia (Kunth) Cass. The chemical analysis was conducted by GC-MS and GC-FID, on two orthogonal capillary columns. A total of 72 compounds were detected and quantified with at least one column, corresponding to about 85% by weight of the whole oil mass. Of the 72 components, 70 were identified by comparing the respective linear retention indices and mass spectra with data from the literature, whereas the two main constituents were identified by preparative purification and NMR experiments. The quantitative analysis was carried out calculating the relative response factor of each compound according to their combustion enthalpy. The major constituents of the EO (≥3%) were: furanoeremophilane (31.3-28.3%), bakkenolide A (17.6-16.3%), caryophyllene oxide (6.0-5.8%), and (E)-ß-caryophyllene (4.4%). Additionally, the hydrolate was also analyzed with respect to the dissolved organic phase. About 40.7-43.4 mg/100 mL of organic compounds was detected in solution, of which p-vinylguaiacol was the main component (25.4-29.9 mg/100 mL). Finally, the enantioselective analysis of some chiral terpenes was carried out, with a capillary column based on ß-cyclodextrin chiral stationary phase. In this analysis, (1S,5S)-(-)-α-pinene, (1S,5S)-(-)-ß-pinene, (S)-(+)-α-phellandrene, (S)-(+)-ß-phellandrene, and (S)-(-)-terpinen-4-ol were detected as enantiomerically pure, whereas (S)-(-)-sabinene showed an enantiomeric excess of 69.2%. The essential oil described in the present study is a good source of two uncommon volatile compounds: furanoeremophilane and bakkenolide A. The former lacks bioactivity information and deserves further investigation, whereas the latter is a promising selective anticancer product.
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An essential oil, distilled from the leaves of the Andean species Gynoxys rugulosa Muschl., is described in the present study for the first time. The chemical composition was qualitatively and quantitatively determined by GC-MS and GC-FID, respectively. On the one hand, the qualitative composition was obtained by comparing the mass spectrum and the linear retention index of each component with data from literature. On the other hand, the quantitative composition was determined by calculating the relative response factor of each constituent, according to its combustion enthalpy. Both analyses were carried out with two orthogonal columns of nonpolar and polar stationary phases. A total of 112 compounds were detected and quantified with at least one column, corresponding to 87.3-93.0% of the whole oil mass. Among the 112 detected components, 103 were identified. The main constituents were α-pinene (5.3-6.0%), (E)-ß-caryophyllene (2.4-2.8%), α-humulene (3.0-3.2%), germacrene D (4.9-6.5%), δ-cadinene (2.2-2.3%), caryophyllene oxide (1.6-2.2%), α-cadinol (3.8-4.4%), 1-nonadecanol (1.7-1.9%), 1-eicosanol (0.9-1.2%), n-tricosane (3.3-3.4%), 1-heneicosanol (4.5-5.8%), n-pentacosane (5.8-7.1%), 1-tricosanol (4.0-4.5%), and n-heptacosane (3.0-3.5%). Furthermore, an enantioselective analysis was carried out on the essential oil, by means of two cyclodextrin-based capillary columns. The enantiomers of α-pinene, ß-pinene, sabinene, α-phellandrene, ß-phellandrene, linalool, α-copaene, terpinen-4-ol, α-terpineol, and germacrene D were detected, and the respective enantiomeric excess was calculated.
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Kaunia longipetiolata (Sch.Bip. ex Rusby) R. M. King and H. Rob. (Asteraceae) is a plant native to southern Ecuador. The dry leaves afforded, by steam distillation, an essential oil that was qualitatively and quantitatively analyzed by GC-MS and GC-FID, respectively, on two orthogonal columns of different polarity. Sesquiterpenes predominated in the volatile fraction, among which α-zingiberene (19.7-19.1%), ar-curcumene (17.3-18.1%), caryophyllene oxide (5.1-5.3%), (Z)-ß-caryophyllene (3.0-3.1%), (2Z,6Z)-farnesal (2.6-3.6%), and spathulenol (2.0-2.1%) were the major components. In addition to the identified compounds, two main unidentified constituents (possibly oxygenated sesquiterpenes) with probable molecular masses of 292 and 230, respectively, were detected. They constituted about 5% and 8% (w/w), respectively, of the whole essential oil. The oil chemical composition was complemented with the enantioselective analysis of ten chiral components. Four scalemic mixtures and six enantiomerically pure terpenes were identified. An enantiomeric excess (ee) was determined for (1R,5R)-(+)-ß-pinene (65.0%), (R)-(-)-α-phellandrene (94.6%), (S)-(+)-linalool (15.0%), and (R)-(-)-terpinen-4-ol (33.8%). On the other hand, (1R,5R)-(+)-α-pinene, (1R,5R)-(+)-sabinene, (S)-(-)-limonene, (S)-(+)-ß-phellandrene, (1R,2S,6S,7S,8S)-(-)-α-copaene, and (R)-(+)-germacrene D were enantiomerically pure. Finally, the non-volatile fraction obtained by extraction of the leaves with MeOH was investigated. Eight known compounds were isolated by liquid column chromatographic separations. Their structures were determined by NMR spectroscopy as dehydroleucodine, kauniolide, (3S,3aR,4aR,6aS,9aS,9bR)-3-hydroxy-1,4a-dimethyl-7-methylene-5,6,6a,7,9a,9b-hexahydro-3H-oxireno[2',3':8,8a]azuleno[4,5-b]furan-8(4aH)-one, novanin, bisabola-1,10-diene-3,4-trans-diol, (R)-2-(2-(acetoxymethyl)oxiran-2-yl)-5-methylphenyl isobutyrate, eupalitin-3-O-glucoside, and 3,5-di-O-caffeoylquinic acid. Literature data about the identified metabolites indicate that K. longipetiolata is a rich source of biologically active natural products.
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A method to identify anticancer compounds in plants was proposed based on the hypothesis that these compounds are primarily present in plants to provide them with an ecological advantage over neighboring plants and other competitors. According to this view, identifying plants that contain compounds that inhibit or interfere with the development of other plant species may facilitate the discovery of novel anticancer agents. The method was developed and tested using Magnolia grandiflora, Gynoxys verrucosa, Picradeniopsis oppositifolia, and Hedyosmum racemosum, which are plant species known to possess compounds with cytotoxic activities. Plant extracts were screened for growth inhibitory activity, and then a thin-layer chromatography bioautography assay was conducted. This located the major antileukemic compounds 1, 2, 4, and 5 in the extracts. Once the active compounds were located, they were extracted and purified, and their structures were determined. The growth inhibitory activity of the purified compounds showed a significant correlation with their antileukemic activity. The proposed approach is rapid, inexpensive, and can easily be implemented in areas of the world with high biodiversity but with less access to advanced facilities and biological assays.
Asunto(s)
Asteraceae , Asteraceae/química , Cromatografía en Capa Delgada , Extractos Vegetales/química , Extractos Vegetales/farmacología , PlantasRESUMEN
A previously uninvestigated essential oil (EO) was distilled from Gynoxys miniphylla Cuatrec. (Asteraceae) and submitted to chemical and enantioselective analyses. The qualitative and quantitative analyses were conducted by GC-MS and GC-FID, over two orthogonal columns (5%-phenyl-methylpolysiloxane and polyethylene glycol stationary phases). Major constituents (≥2%) were, on both columns, respectively, as follows: α-phellandrene (16.1-17.2%), α-pinene (14.0-15.0%), germacrene D (13.3-14.8%), trans-myrtanol acetate (8.80%), δ-cadinene (4.2-4.6%), ß-phellandrene (3.3-2.8%), (E)-ß-caryophyllene (3.1-2.0%), o-cymene (2.4%), α-cadinol (2.3-2.6%), and α-humulene (1.7-2.0%). All the quantified compounds corresponded to 93.5-97.3% by weight of the whole essential oil, with monoterpenes counting for 53.8-55.6% of the total, and sesquiterpenes for 38.5-41.4%. For what concerns the enantioselective analyses, the chiral components were investigated through a ß-cyclodextrin-based enantioselective column (2,3-diethyl-6-tert-butyldimethylsilyl-ß-cyclodextrin). A total of six chiral metabolites were analysed and the respective enantiomeric excess calculated as follows: (1S,5S)-(-)-α-pinene (98.2%), (1S,5S)-(-)-ß-pinene (11.9%), (1R,5R)-(+)-sabinene (14.0%), (R)-(-)-α-phellandrene (100.0%), (R)-(-)-ß-phellandrene (100.0%), and (S)-(-)-germacrene D (95.5%). According to the chemical composition and enantiomeric distribution of major compounds, this EO can be considered promising as a cholinergic, antiviral and, probably, analgesic product.
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As part of a project devoted to the phytochemical study of Ecuadorian biodiversity, new essential oils are systematically distilled and analysed. In the present work, Jungia rugosa Less (Asteraceae) has been selected and some wild specimens collected to investigate the volatile fraction. The essential oil, obtained from fresh leaves, was analysed for the first time in the present study. The chemical composition was determined by gas chromatography, coupled to mass spectrometry (GC-MS) for qualitative analysis, and to flame ionization detector (GC-FID) for quantitation. The calculation of relative response factors (RRF), based on combustion enthalpy, was carried out for each quantified component. Fifty-six compounds were identified and quantified in a 5% phenyl-polydimethylsiloxane non-polar column and 53 compounds in a polyethylene glycol polar column, including four undetermined compounds. The main feature of this essential oil was the exclusive sesquiterpenes content, both hydrocarbons (74.7% and 80.4%) and oxygenated (8.3% and 9.6%). Major constituents were: γ-curcumene (47.1% and 49.7%) and ß-sesquiphellandrene (17.0% and 17.9%), together with two abundant undetermined oxygenated sesquiterpenes, whose abundance was 6.7-7.2% and 4.7-3.3%, respectively. In addition, the essential oil was submitted to enantioselective evaluation in two ß-cyclodextrin-based enantioselective columns, determining the enantiomeric purity of a minor component (1S,2R,6R,7R,8R)-(+)-α-copaene. Finally, the AChE inhibition activity of the EO was evaluated in vitro. In conclusion, this volatile fraction is suitable for further investigation, according to two main lines: (a) the purification and structure elucidation of the major undetermined compounds, (b) a bio-guided fractionation, intended to investigate the presence of new sesquiterpene AChE inhibitors among the minor components.
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The traditional Ecuadorian spice Ishpingo, characterized by a strong cinnamon-like aroma, is constituted by the dry cupules of Amazonian species Ocotea quixos. Nevertheless, bark and leaves also present aromatic properties and are sometimes used as substitutes. In the present study, the essential oils, distilled from these morphological structures, are comparatively analyzed for their chemical and enantiomeric compositions. A total of 88 components were identified with 2 orthogonal GC columns, whereas 79, corresponding to more than 94%, were also quantified with at least 1 column. Major compounds were (E)-methyl cinnamate in cupules (35.9-34.2%), (E)-cinnamaldehyde in bark (44.7-47.0%), and (E)-cinnamyl acetate (46.0-50.4%) in leaves. For what concerns the enantioselective analysis, 10 chiral terpenes and terpenoids were detected, of which 6 were present as enantiomeric pairs in at least 1 essential oil, the others being enantiomerically pure. Both quantitative and enantioselective analyses were submitted to Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA), where their results confirmed significative difference among the three products.
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Dehydroleucodine is a bioactive sesquiterpene lactone. Herein, four dehydroleucodine amino derivatives were synthesized using the amines proline, piperidine, morpholine, and tyramine, and spectroscopic methods and single-crystal X-ray diffraction unambiguously established their structures. The cytotoxic activity of these compounds was evaluated against eight acute myeloid leukemia cell lines, and their toxicity to peripheral blood mononuclear cells was also determined. The proline adduct was the most active compound, it showed anti-leukemic activity, upregulated heme oxygenase 1 (HMOX1) and the primary stress-inducible isoform of the heath shock 70 kDa protein 1 (HSPA1A), and downregulated NFkB1 transcription, it was also found to be about 270 times more water soluble than dehydroleucodine.
Asunto(s)
Proliferación Celular/efectos de los fármacos , Lactonas/química , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucocitos Mononucleares/efectos de los fármacos , Sesquiterpenos/química , Línea Celular Tumoral , Cristalografía por Rayos X , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/genética , Hemo-Oxigenasa 1/genética , Humanos , Lactonas/síntesis química , Lactonas/farmacología , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Morfolinas/química , Subunidad p50 de NF-kappa B/genética , Piperidinas/química , Sesquiterpenos/síntesis química , Sesquiterpenos/farmacología , Tiramina/químicaRESUMEN
Gaiadandendron punctatum G.Don. (violeta de campo) is a plant used in traditional medicine by the Saraguro people, an ancient indigenous group that lives in southern Ecuador. From samples collected in the region, six glycoside flavonoids, five with quercetin and one with kaempferol as aglycon, were isolated and characterized from hydroalcoholic extracts of leaves and flowers. Rutin (2) was found in flowers and leaves, nicotiflorin (1) was found in flowers, artabotryside A (3) was found in leaves, and three novel quercetin flavonoid glycosides were isolated, elucidated, and characterized via 1D and 2D NMR experiments (1H, 13C, COSY, DEPT, HMBC, HSQC, TOCSY, NOESY, ROESY), acid hydrolysis-derivatization-GC-MS analysis, HPLC-MS, IR, UV, and optical rotation. The new quercetin flavonoid glycosides were named hecpatrin (4) (isolated from leaves), gaiadendrin (5) (isolated from leaves), and puchikrin (6) (isolated from flowers). The hydroalcoholic extracts of the leaves presented antimicrobial activity against Micrococcus luteus, Staphylococcus aureus, and Enterococcus faecalis and the hydroalcoholic extract of the flowers was active against Micrococcus luteus. However, glycoside flavonoids presented scarce antimicrobial activity against bacteria. Hydroalcoholic extracts from leaves and flowers and their secondary metabolites showed inhibition against the α-glucosidase enzyme at different concentrations. Rutin, gaiadendrin, and nicotiflorin showed competitive α-glucosidase inhibition, while hecpatrin presented non-competitive inhibition.
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Antiinfecciosos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Glicósidos/aislamiento & purificación , Loranthaceae/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Ecuador , Enterococcus faecalis/efectos de los fármacos , Flavonoides/química , Flavonoides/farmacología , Flores/química , Cromatografía de Gases y Espectrometría de Masas , Glicósidos/química , Glicósidos/farmacología , Pruebas de Sensibilidad Microbiana , Micrococcus luteus/efectos de los fármacos , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Quercetina , Staphylococcus aureus/efectos de los fármacosRESUMEN
[This corrects the article DOI: 10.1371/journal.pone.0136527.].
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Ecuador owns many high quantity and wealthy ecosystems that contain an elevated biodiversity in flora and fauna. The use of native medicinal plants has been maintained by at least 18 different indigenous cultures; furthermore, this country has been the witness of the discovery of important medicinal plants, such as Cinchona, and is an understudied resource of new natural products. The objective of this review is to update the ethnopharmacological and phytochemical studies accomplished on the Ecuadorian flora, pointing to the 253 native families and more than 15,000 species registered at present.
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Etnofarmacología , Fitoquímicos , Plantas Medicinales/química , Plantas Medicinales/clasificación , Humanos , FitoterapiaRESUMEN
The sesquiterpene lactones dehydroleucodine (1) and leucodine (2) were isolated from Gynoxys verrucosa, a species used in traditional medicine in southern Ecuador. The activity of these compounds was determined against eight acute myeloid leukemia (AML) cell lines and compared with their activity against normal peripheral blood mononuclear cells. Compound 1 showed cytotoxic activity against the tested cell lines, with LD50 values between 5.0 and 18.9 µM. Compound 2 was inactive against all of the tested cell lines, demonstrating that the exocyclic methylene in the lactone ring is required for cytotoxic activity. Importantly, compound 1 induced less toxicity to normal blood cells than to AML cell lines and was active against human AML cell samples from five patients, with an average LD50 of 9.4 µM. Mechanistic assays suggest that compound 1 has a similar mechanism of action to parthenolide (3). Although these compounds have significant structural differences, their lipophilic surface signatures show striking similarities.
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Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Asteraceae/química , Lactonas/aislamiento & purificación , Lactonas/farmacología , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Antineoplásicos/química , Western Blotting , Ensayos de Selección de Medicamentos Antitumorales , Ecuador , Células HL-60 , Células HeLa , Humanos , Lactonas/química , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucocitos Mononucleares/efectos de los fármacos , Medicina Tradicional , Estructura Molecular , Sesquiterpenos/químicaRESUMEN
Blends of poly(lactic acid) (PLA) and poly(ε-caprolactone) (PCL), loaded with different amounts of Amoxicillin antibiotic (AMOX) were electrospun to investigate their release properties and obtain a controlled and tuneable release. The processing parameters for electrospinning were set up and reliable membranes were obtained. Morphology and thermal behaviour were found dependent on the component ratio as well as on the incorporated drug amount. A very different release kinetics of the two pristine polymers, very rapid for PCL and very slow for PLA, reflected in intermediate release time. However comparing the release amount with that predicted by the mixture rule a preferential incorporation of AMOX into PLA can be inferred.
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Amoxicilina/farmacocinética , Portadores de Fármacos/química , Técnicas Electroquímicas/métodos , Ácido Láctico/química , Nanofibras/química , Poliésteres/química , Polímeros/química , Amoxicilina/química , NanotecnologíaRESUMEN
Accumulating evidence supports the idea that secondary metabolites obtained from medicinal plants (phytometabolites) may be important contributors in the development of new chemotherapeutic agents to reduce the occurrence or recurrence of cancer. Our study focused on Dehydroleucodine (DhL), a sesquiterpene found in the provinces of Loja and Zamora-Chinchipe. In this study, we showed that DhL displayed cytostatic and cytotoxic activities on the human cerebral astrocytoma D384 cell line. With lactone isolated from Gynoxys verrucosa Wedd, a medicinal plant from Ecuador, we found that DhL induced cell death in D384 cells by triggering cell cycle arrest and inducing apoptosis and DNA damage. We further found that the cell death resulted in the increased expression of CDKN1A and BAX proteins. A marked induction of the levels of total TP73 and phosphorylated TP53, TP73, and γ-H2AX proteins was observed in D384 cells exposed to DhL, but no increase in total TP53 levels was detected. Overall these studies demonstrated the marked effect of DhL on the diminished survival of human astrocytoma cells through the induced expression of TP73 and phosphorylation of TP73 and TP53, suggesting their key roles in the tumor cell response to DhL treatment.