A New Glucosyl Flavone with Inhibitory Activity of Cancer Cell Viability and Other Bioactive Constituents from the Traditional Kurdish Plant Plantago loeflingii L.

A new glucosyl flavone, 5,7,2',5'-tetrahydroxyflavone 7-O-ß-d-glucopyranoside, named loeflingiin, together with apigenin 6-C-glucoside (isovitexin), coumarins citropten and isompinellin, triterpenoids betulin and betulinic acid, and a mixture of phytosterols ß-sitosterol, stigmasterol and campesterol were isolated for the first time from the leaves of wild Plantago loeflingii L. (Plantaginaceae) collected in the Iraqi Kurdistan region. The plant is used by local people to treat wounds and as a vulnerary remedy. The structures of isolated compounds were determined by spectroscopic analysis. The activities of isovitexin and loeflingiinon the viability of breast (MCF7), ovarian (BG-1), endometrial (Ishikawa), and mesothelioma (IST-MES1) human cancer cells and two normal cell lines were determined with an MTT assay. Notably, the new 7-O-glucosyl flavone showed effects higher than cisplatin against the Ishikawa and IST-MESI cell lines. The significant biological activities exhibited by all the compounds isolated from P. loeflingii provided scientific evidence to support the use of the plant in the Kurdish traditional medicine.

A Validated HPLC-UV-ESI-IT-MS Method for the Quantification of Carnosol in Lepechinia mutica, a Medicinal Plant Endemic to Ecuador.

The diphenolic diterpene carnosol was isolated from several species of the family Lamiaceae, including Lepechinia mutica, a medicinal plant endemic to Ecuador. The compound has exhibited high antioxidant, anti-inflammatory, antimicrobial, neuroprotective, and antifungal properties, as well as promising cytotoxicity against prostate, breast, skin, leukemia, and human colon cancer cell lines. In this paper, we developed and validated a simple, accurate, and reliable analytical HPLC-UV-ESI-IT-MS method, carried out on a C18 column, which is potentially suitable to quantify carnosol in plant extracts. The procedure complied with the established ICH validation parameters of analytical range (linearity in the range of 0.19-5.64 µg/g dried leaves; REAVERGE = 4.9%; R2 = 0.99907), analysis repeatability (RSD = 2.8-3.6%), intermediate precision (RSD = 1.9-3.6%), accuracy (estimated as % carnosol recovery in the range of 81 to 108%), and robustness. Finally, the LOD (0.04 µg/mg) and LOQ (0.19 µg/mg) values of carnosol/dried leaves were determined. Using this validated method, the content of carnosol in L. mutica was estimated to be 0.81 ± 0.04 mg/g of dried leaves (0.081%).

Chemical Composition and In Vitro Evaluation of Antioxidant and Antiproliferative Effects of Volatile Oils Hydrodistilled from Onobrychis carduchorum C.C. Towns., a Kurdish Traditional Plant.

The volatile oils hydrodistilled from the aerial parts and roots of O. carduchorum C.C Towns. (Fabaceae) have been chemically characterized for the first time. A total of 43 constituents with an abundance >0.03% were identified and quantified in the two oils by GC/MS and GC/FID analyses. They comprise 38 components (98.58%) of the oil isolated from the aerial parts (OCA) and 34 components (93.33%) of the oil from the roots (OCR). Six constituents, α-pinene (23.11 ± 0.1%), ß-elemene (17.33 ± 0.1%), 1,8-cineole (12.15 ± 0.2%), furfural (7.91 ± 0.1%), terpineol-4-ol (6.32 ± 0.2%), and limonene (4.13 ± 0.1%), accounted for about 75% of the total OCA oil. On the other hand, 1,8-cineole (15.79 ± 0.1%), furfural (10.44 ± 0.1%), ß-elemene (10.14 ± 0.2%), α-terpineol (7.74 ± 0.1%), linalool (7.45 ± 0.1%), and α-pinene (4.76 ± 0.1%) made up about 60% of the OCR oil. The IC50 values of the scavenging activities of the OCA and OCR oils towards the DPPH radical and H2O2 were 79.8 ± 0.5 and 153.3 ± 0.6 µg/mL and 394.09 ± 0.2 and 311.67 ± 0.4 µg/mL, respectively. In addition, in the MTS assay, the OCA and OCR oils showed significant antiproliferative effects against T47D, MDA-MB-453, BG-1, and A549 human cancer cells that were more powerful than those against two normal human cell lines, HEK-293 and HFF-1. The abundant presence of ß-elemene as an antiproliferative component of the two oils suggested the existence of a new chemotype of O. carduchorum.

Constituents and Selective BuChE Inhibitory Activity of the Essential Oil from Hypericum aciculare Kunth.

A potential source of new inhibitors of cholinesterase enzymes are certain compounds of natural plant origin; therefore, in the study described herein we have determined the chemical composition and the acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities of the essential oil (EO) steam distilled from aerial parts of Hypericum aciculare, which was collected in southern Ecuador. The oil qualitative and quantitative composition was determined by GC-FID and GC-MS using a non-polar and a polar chromatographic column. A total of fifty-three constituents were identified, that accounted for about 98% of the EO content. The hydrocarbon n-nonane (16.4-28.7%) and the aldehyde n-decanal (20.7-23.1%) were the predominant oil constituents. In addition, the EO showed significant inhibition of BuChE (IC50 = 28.3 ± 2.7 µg/mL) and moderate activity towards AChE (IC50 = 82.1 ± 12.1 µg/mL). Thus, the EO from H. aciculare aerial parts is an interesting candidate to investigate the mechanism of selective ChE inhibition by the two ChE enzymes with the aim to discover potential targets to control the progression of the Alzheimer's disease (AD).

New Tricholidic Acid Triterpenoids from the Mushroom Tricholoma ustaloides Collected in an Italian Beech Wood.

The secondary metabolites produced by Tricholoma ustaloides Romagn., a mushroom species belonging to the large Tricholoma genus (Basidiomycota, Tricholomataceae), are unknown. Therefore, encouraged by the interesting results obtained in our previous chemical analyses of a few Tricholoma species collected in Italian woods, we aimed to investigate the secondary metabolites of Tricholoma ustaloides. The chemical analysis involved the isolation and characterization of secondary metabolites through an extensive chromatographic study. The structures of isolated metabolites, including the absolute configuration, were established based on a detailed analysis of MS, NMR spectroscopic, optical rotation, and circular dicroism data, and on comparison with those of related compounds reported in the literature. Two novel lanostane triterpenoids, named tricholidic acids B and C, together with triglycerides, a mixture of free fatty acids, five unidentified metabolites, and the known rare saponaceolides F and J, tricholidic acid, and tricholomenyn C, were isolated from an EtOAc extract of fruiting bodies of Tricholoma ustaloides that were collected in an Italian beech wood. This is the second example of isolation of tricholidic acid derivatives from a natural source. Saponaceolides F and J exhibited high cytotoxicity (IC50 values ≤ 10 µM) against a panel of five human cancer cell lines. The toxicity against myeloid leukemia (HL-60), lung cancer (A-549), hepatocellular cancer (HepG2), renal cancer (Caki-1), and breast cancer (MCF-7) cells was higher than that shown by the very well-known cytotoxic drug cisplatin.

Constituents, Enantiomeric Content, and ChE Inhibitory Activity of the Essential Oil from Hypericum laricifolium Juss. Aerial Parts Collected in Ecuador.

The physical properties, chemical composition, enantiomer distribution, and cholinesterase (ChE) inhibitory activity were determined for a steam-distilled essential oil (EO), with a yield of 0.15 ± 0.05 % (w/w), from H. laricifolium aerial parts, collected in southern Ecuador. The oil qualitative and quantitative analyses were performed by GC-EIMS and GC-FID techniques, using two capillary columns containing a non-polar 5%-phenyl-methylpolysiloxane and a polar polyethylene glycol stationary phase, respectively. The main constituents (>10%) detected on the two columns were, respectively, limonene (24.29, 23.16%), (E)-ß-ocimene (21.89, 27.15%), and (Z)-ß-ocimene (12.88, 16.03%). The EO enantioselective analysis was carried out using a column based on 2,3-diethyl-6-tert-butyldimethylsilyl-ß-cyclodextrin. Two mixtures of chiral monoterpenes were detected containing (1R,5R)-(+)-α-pinene (ee = 83.68%), and (S)-(-)-limonene (ee = 88.30%) as the major enantiomers. This finding led to some hypotheses about the existence in the plant of two enantioselective biosynthetic pathways. Finally, the EO exhibited selective inhibitory effects in vitro against butyrylcholinesterase (BuChE) (IC50 = 36.80 ± 2.40 µg/mL), which were about three times greater than against acetylcholinesterase (IC50 = 106.10 ± 20.20). Thus, the EO from Ecuadorian H. laricifolium is an interesting candidate for investigating the mechanism of the selective inhibition of BuChE and for discovering novel drugs to manage the progression of Alzheimer's disease.

Essential Oil and Non-Volatile Metabolites from Kaunia longipetiolata (Sch.Bip. ex Rusby) R. M. King and H. Rob., an Andean Plant Native to Southern Ecuador.

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.

Iridoids Isolation from a Phytochemical Study of the Medicinal Plant Teucrium parviflorum Collected in Iraqi Kurdistan.

Herbal medicines are still widely practiced in Kurdistan Region-Iraq, especially by people living in villages on mountainous regions. Among plants belonging to the genus Teucrium (family Lamiaceae), which are commonly employed in the Kurdish traditional medicine, we have analyzed, for the first time, the methanol and aqueous methanol extracts of T. parviflorum aerial parts. The plant is mainly used by Kurds to treat jaundice, liver disorders and stomachache. We aimed to determine the phytochemical profile of the extracts and the structures of the main components, so to provide a scientific rationale for the ancient use of the plant in the ethno-pharmacological field. TLC analysis of the two extracts on silica gel and reversed phase TLC plates, using different visualization systems, indicated similar contents and the presence of phenolics, flavonoids, terpenoids and sugars. The chlorophyll-free extracts exhibited weak/no antimicrobial activities against a panel of bacteria (MICs = 800-1600 µg/mL) and fungal strains (MICs ≥ 5 mg/mL). At the concentration of 600 µg/mL, the methanol extract showed moderate antiproliferative effects against A549 and MCF-7 cancer cell lines in the MTS assay. Moreover, both extracts exhibited a significant dose-dependent free radical scavenging action against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical (EC50 = 62.11 and 44.25 µg/mL, respectively). In a phytochemical study, a high phenolic content (77.08 and 81.47 mg GAE/g dry extract, respectively) was found in both extracts by the Folin-Ciocalteu assay. Medium pressure liquid chromatographic (MPLC) separation of the methanol extract on a reversed phase cartridge eluted with a gradient of MeOH in H2O, afforded two bioactive iridoid glucosides, harpagide (1) and 8-O-acetylharpagide (2). The structures of 1 and 2 were established by spectral data, chemical reactions, and comparison with the literature. Interestingly, significant amounts of hepatotoxic furano neo-clerodane diterpenoids, commonly occurring in Teucrium species, were not detected in the extract. The wide range of biological activities reported in the literature for compounds 1 and 2 and the significant antiradical effects of the extracts give scientific support to the traditional use in Iraqi Kurdistan of T. parviflorum aerial parts for the preparation of herbal remedies.

Chemical Characterization and Biological Activity of the Essential Oil from Araucaria brasiliensis Collected in Ecuador.

The purpose of this study was to determine the chemical composition, physical properties, enantiomeric composition and cholinesterase inhibitory activity of the essential oil (EO) steam-distilled from the leaves of the plant Araucaria brasiliensis Loud. collected in Ecuador. The chemical composition was determined by gas chromatography coupled to mass spectrometry (GC-MS) analysis on two capillary GC columns (DB5-ms and HP-INNOWax). Thirty-three compounds were identified in the EO; the main compounds were beyerene (26.08%), kaurene (24.86%), myrcene (11.02%), α-pinene (9.99%) and 5,15-rosadiene (5.87%). Diterpene hydrocarbons (65.41%), followed by monoterpene hydrocarbons (21.11%), were the most representative components of the EO. Enantioselective analysis of the EO showed four pairs of enantiomeric compounds, α-pinene, camphene, γ-muurolene and δ-cadinene. In an in vitro assay, the EO showed moderate inhibitory activity towards the enzyme butyrylcholinesterase (BuChE) (95.7 µg/mL), while it was inactive towards acetylcholinesterase (AChE) (225.3 µg/mL). Further in vivo studies are needed to confirm the anticholinesterase potential of the EO.

Essential Oil and Major Non-Volatile Secondary Metabolites from the Leaves of Amazonian Piper subscutatum.

The essential oil and the major non-volatile secondary metabolites from the leaves of Piper subscutatum (Miq.) C. DC. (Family Piperaceae), collected in the Ecuadorian Amazon, were analyzed for the first time in the present study. The essential oil was submitted to chemical and enantioselective analyses by GC-MS and GC-FID. (E)-ß-caryophyllene (25.3-25.2%), ß-chamigrene (10.3-7.8%), (E)-nerolidol (8.1-7.7%), ß-selinene (7.2-7.7%), δ-cadinene (2.7-3.9%), bicyclogermacrene (3.7-2.4%), and ß-pinene (2.6-3.4%) were the major components. The enantioselective analysis, carried out on a ß-cyclodextrin-based column, showed four scalemic mixtures in which (1R,5R)-(+)-α-pinene, (1S,5S)-(-)-ß-pinene, (S)-(-)-limonene, and (1R,2S,6S,7S,8S)-(-)-α-copaene were the major enantiomers, with enantiomeric excesses of 28.8%, 77.8%, 18.4%, and 6.0%, respectively. The study was complemented with the chemical analysis of the organic fraction dissolved in the hydrolate, whose major components were 6-methyl-5-hepten-2-one (63.7-64.4%) and linalool (6.5-6.0%). Concerning the non-volatile fraction, five lignans were the major components. (-)-Beilshminol B, (-)-grandisin, (-)-3',4'-methylenedioxy-3,4,5-trimethoxy-7,7'-epoxylignan, (-)-3',4'-methylenedioxy-3,4,5,5'-tetramethoxy-7,7'-epoxylignan, and (-)-3,4,3',4'-dimethylenedioxy-5,5'-dimethoxy-7,7'-epoxylignan were identified by means of NMR spectroscopy, mass spectrometry and X-ray crystallography. The absolute configuration 7S,8S,7'S,8'S was tentatively assigned to all of them.

Selective BuChE Inhibitory Activity, Chemical Composition, and Enantiomeric Content of the Essential Oil from Salvia leucantha Cav. Collected in Ecuador.

The essential oil (EO) of Salvia leucantha Cav. was isolated by steam distillation of the aerial parts collected in the South of Ecuador. Its physical properties were evaluated and the chemical composition of the oil was determined by GC-MS and GC-FID analyses using two chromatographic columns, DB-5ms and HP-INNOWax. Six major compounds were identified, namely, the sesquiterpenes 6.9-guaiadiene (19.14%), (E)-caryophyllene (16.80%), germacrene D (10.22%), (E)-ß-farnesene (10.00%), and bicyclogermacrene (7.52%), and the monoterpenoid bornyl acetate (14.74%). Furthermore, four pairs of enantiomers were determined by enantioselective GC-MS of the essential oil. (-)-germacrene D and (+)-α-pinene showed the highest enantiomeric excess (ee%). In an in vitro assay, the essential oil demonstrated an interesting inhibitory activity of the enzyme butyrylcholinesterase (BuChE), with an IC50 = 32.60 µg/mL, which is the highest determined for a Salvia species. In contrast, the oil was weakly active against acetylcholinesterase (AChE) with an IC50 > 250 µg/mL.

Structures and Bioactivities of Steroidal Saponins Isolated from the Genera Dracaena and Sansevieria.

The species Dracaena and Sansevieria, that are well-known for different uses in traditional medicines and as indoor ornamental plants with air purifying property, are rich sources of bioactive secondary metabolites. In fact, a wide variety of phytochemical constituents have been isolated so far from about seventeen species. This paper has reviewed the literature of about 180 steroidal saponins, isolated from Dracaena and Sansevieria species, as a basis for further studies. Saponins are among the most characteristic metabolites isolated from the two genera. They show a great variety in structural motifs and a wide range of biological activities, including anti-inflammatory, anti-microbial, anti-proliferative effects and, in most case, remarkable cytotoxic properties.

Phytochemistry of Verbascum Species Growing in Iraqi Kurdistan and Bioactive Iridoids from the Flowers of Verbascum calvum.

Traditional medicine is still widely practiced in Iraqi Kurdistan, especially by people living in villages on mountainous regions; medicinal plants are also sold in the markets of the large towns, such as at Erbil, the capital of the Kurdistan Autonomous Region. About a dozen of Verbascum species (Scrophulariaceae) are commonly employed in the Kurdish traditional medicine, especially for treating burns and other skin diseases. However, the isolation of bioactive secondary metabolites from these plants has not been the subject of intense scientific investigations in Iraq. Therefore, the information reported in the literature about the species growing in Kurdistan has been summarized in the first part of this paper, although investigations have been performed on vegetable samples collected in neighbouring countries, such as Turkey and Iran. In the second part of the work, we have investigated, for the first time, the contents of a methanol and a hydromethanol extract of V. calvum flowers. The extracts exhibited weak antimicrobial activities, whereas the methanol extract showed significant antiproliferative effects against an A549 lung cancer cell line. Moreover, both extracts exhibited a significant dose-dependent free radical scavenging action against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, comparable to that of ascorbic acid. In the subsequent phytochemical study, a high phenolic content was determined in both extracts by the Folin-Ciocalteu assay and medium-pressure liquid chromatographic (MPLC) separation led to the isolation of iridoid glucosides ajugol and aucubin from the methanol extract. In conclusion, the high anti-inflammatory effects of aucubin and the remarkable antioxidant (antiradical) properties of the extracts give scientific support to the traditional use of V. calvum flowers for the preparation in Kurdistan of remedies to cure skin burns and inflammations.

Bioactive Phytochemical Constituents of Wild Edible Mushrooms from Southeast Asia.

Mushrooms have a long history of uses for their medicinal and nutritional properties. They have been consumed by people for thousands of years. Edible mushrooms are collected in the wild or cultivated worldwide. Recently, mushroom extracts and their secondary metabolites have acquired considerable attention due to their biological effects, which include antioxidant, antimicrobial, anti-cancer, anti-inflammatory, anti-obesity, and immunomodulatory activities. Thus, in addition to phytochemists, nutritionists and consumers are now deeply interested in the phytochemical constituents of mushrooms, which provide beneficial effects to humans in terms of health promotion and reduction of disease-related risks. In recent years, scientific reports on the nutritional, phytochemical and pharmacological properties of mushroom have been overwhelming. However, the bioactive compounds and biological properties of wild edible mushrooms growing in Southeast Asian countries have been rarely described. In this review, the bioactive compounds isolated from 25 selected wild edible mushrooms growing in Southeast Asia have been reviewed, together with their biological activities. Phytoconstituents with antioxidant and antimicrobial activities have been highlighted. Several evidences indicate that mushrooms are good sources for natural antioxidants and antimicrobial agents.

Selective BuChE inhibitory activity, chemical composition, and enantiomer content of the volatile oil from the Ecuadorian plant Clinopodium brownei

ABSTRACT This paper describes the chemical composition and the enantiomer content of the volatile oil hydrodistilled from Clinopodium brownei (Sw.) Kuntze, Lamiaceae. The plant was collected in the South of Ecuador. Thirty one components were identified by GC-MS, which accounted for the 96.15% of the volatile oil. The major components were pulegone (48.44%), menthone (34.55%) and β-acorenol (3.41%). Oxygenated monoterpenes (86.06%), followed by oxygenated sesquiterpenes (5.36%) constituted the most abundant fractions. The enantiomeric compositions of β-pinene, sabinene, 3-octanol, menthone, pulegone and menthyl acetate were determined by enantioselective GC-MS. (-)-Menthone showed the highest enantiomeric excess (ee = 83.4%). In in vitro tests, the volatile oil showed high selective inhibitory activity for butyrylcholinesterase with an IC50, 13.4 ± 1.8 µg/ml. In contrast, it was weakly active against acetylcholinesterase with an IC50 >250 µg/ml.

Carnosol from Lepechinia mutica and tiliroside from Vallea stipularis: Two promising inhibitors of BuChE

Abstract Lepechinia mutica (Benth.) Epling, Lamiaceae, and Vallea stipularis L.f., Elaeocarpaceae, are the object of the present study. These plants are endemic to the Andean region and have attracted our attention on the basis of interesting results obtained in a preliminary anticholinesterase screening. Actually, carnosol and tiliroside, isolated from L. mutica and V. stipularis, respectively, have shown a promising selective inhibitory activity against butyrylcholinesterase. Specifically, the anti-butyrylcholinesterase activity of carnosol was 5.15 µM and that of tiliroside was 52.9 µM, compared to 8.568 ± 0.570 µM of the positive control Donepezil. Carnosol and tiliroside were purified chromatographically from the ethyl acetate extract of L. mutica and V. stipularis, respectively. Spectrophotometric methods were used for enzymatic studies.

Chemical composition and antimicrobial activity of Myrcianthes fragrans essential oil, a natural aromatizer of the traditional Ecuadorian beverage colada morada.

ETHNOBOTANICAL AND ETHNOMEDICINAL RELEVANCE: The importance given in Ecuador to the rescue of traditional knowledge and nutritional value of ancestral foods and drinks, has stimulated our investigation of the chemical composition and some biological activities of M. fragrans ('arrayán') essential oil, a natural aromatic additive used in the preparation of the traditional fruit-juice 'colada morada', which is typically drunk in the Day of the Dead or All Soul´s Day. MATERIAL AND METHODS: Different essential oils of Myrcianthes fragrans (Sw.) McVaught were obtained by hydrodistillation of the aerial parts of the plant collected in Cerro Villonaco (Loja-Ecuador) at three different phenological growth stages, i.e., during foliation (Fo), flowering (Fl) and fruiting (Fr) stages. The chemical compositions of the essential oils were determined by GC/MS and GC/FID techniques. The antimicrobial activities were determined by the broth microdilution method and reported as minimal inhibitory concentration (MIC, ug/mL). AIMS OF THE STUDY: i) to investigate the traditional uses of arrayán (M. fragrans) in the South region of Ecuador; ii) to identify the main components of the essential oils isolated at different phenological stages; iiì) to test the antimicrobial activity of the essential oils against bacteria and yeasts causing human ailments and a yeast causing food spoilage. RESULTS: 37, 46 and 38 compounds, representing 96.5%, 96.2%, and 95.6% of the three essential oils (Fo, Fl and Fr), respectively, have been identified. Oxygenated monoterpenes (OM) were the major components with percentages of 63.1 (Fo), 49.4 (Fl), and 61.9% (Fr), respectively. The main constituents of the essential oils were the monoterpene aldehydes geranial (1) and neral (2), the content of which varied, depending on the phenological development stage of the plant, spanning from 31.1% and 23.6% (Fo), to 23.6% and 17.8% (Fl), and 29.7% and 24.3% (Fr), respectively. In vitro antimicrobial tests showed that the essential oils from M. fragrans exhibited good activity against the Gram-negative bacteria, K. pneumoniae, and against the yeasts, C. albicans and S. cerevisiae. CONCLUSIONS: The oil is characterized by a high concentration of the monoterpene aldehydes geranial and neral (citral), that make the aroma of colada morada prepared in southern Ecuador quite different from the beverage made in other regions of the country, where other types of myrtles (Myrtaceae spp.) are used. Moreover, the oil may become a new rich source of the important industrial chemical citral. The pleasant aromatic properties and the good in vitro antimicrobial activity of arrayán oil suggest a plausible scientific explanation for the traditional uses of the plant not only as a natural aromatizer of a traditional beverage but also as a natural anti-infective and anti-yeast agent.

Chemical Composition, Enantiomeric Analysis, AEDA Sensorial Evaluation and Antifungal Activity of the Essential Oil from the Ecuadorian Plant Lepechinia mutica Benth (Lamiaceae).

This study describes the GC-FID, GC/MS, GC-O, and enantioselective GC analysis of the essential oil hydrodistilled from leaves of Lepechinica mutica (Lamiaceae), collected in Ecuador. GC-FID and GC/MS analyses allowed the characterization and quantification of 79 components, representing 97.3% of the total sample. Sesquiterpene hydrocarbons (38.50%) and monoterpene hydrocarbons (30.59%) were found to be the most abundant volatiles, while oxygenated sesquiterpenes (16.20%) and oxygenated monoterpenes (2.10%) were the minor components. In order to better characterize the oil aroma, the most important odorants, from the sensorial point of view, were identified by Aroma Extract Dilution Analysis (AEDA) GC-O. They were α-Pinene, ß-Phellandrene, and Dauca-5,8-diene, exhibiting the characteristic woody, herbaceus, and earthy odors, respectively. Enantioselective GC analysis of L. mutica essential oil revealed the presence of twelve couples and two enantiomerically pure chiral monoterpenoids. Their enantiomeric excesses were from a few percent units to 100%. Moreover, the essential oil exhibited moderate in vitro activity against five fungal strains, being especially effective against M. canis, which is a severe zoophilic dermatophyte causal agent of pet and human infections.

Correction: Phytometabolite Dehydroleucodine Induces Cell Cycle Arrest, Apoptosis, and DNA Damage in Human Astrocytoma Cells through p73/p53 Regulation.

[This corrects the article DOI: 10.1371/journal.pone.0136527.].

Composition, Antifungal and Antiproliferative Activities of the Hydrodistilled Oils from Leaves and Flower Heads of Pterocephalus nestorianus Nábelek.

This article reports the first study of the chemical composition, and antifungal and antiproliferative properties of the volatile extracts obtained by hydrodistillation of the flower heads and leaves of the traditional Kurdish medicinal plant Pterocephalus nestorianus Nábelek, collected in the wild. A total of 55 constituents, 43 of the flower heads' oil (PFO) and 46 of the leaves' oil (PLO), respectively, were identified by GC/MS, constituting 99.68% and 99.04% of the two oils, respectively. The oils were obtained in 0.15% and 0.10% yields (w/w), respectively, on air-dried vegetable material. The prevalent constituents of the PFO were α-terpineol (2.41%), α-linalool (6.42%), 6,10,14-trimethylpentadecan-2-one (2.59%), myristic acid (24.65%), and lauric acid (50.44%), while the major components of PLO were (E)-hex-2-enal (2.26%), (E)-hex-2-en-1-ol (2.04), myristic acid (34.03%), and lauric acid (50.35%). The two oils showed significant inhibitory and fungicidal activities against the medically important fungi Candida albicans, Candida tropicalis, Microsporum canis, and Trichophyton mentagrophytes, with minimum inhibitory concentration ranging from 0.7 to 3.3 mg/ml and minimum fungicidal concentration varying from 1.4 to 6.6 mg/ml. The antiproliferative activity of the two oils was assayed against one normal and six human tumor cell lines. Both oils showed selective cytotoxic activity, with IC50 values ranging from 1.4 to 3.3 µg/ml.