Dynamics of alkaloid accumulation in Narcissus cv. Hawera: a source of Sceletium-type alkaloids.

The Sceletium-type alkaloids, known for their anxiolytic and antidepressant activities, have been recently found to be biosynthesized in Narcissus cv. Hawera, which is largely used as an ornamental plant. An alkaloid fraction enriched with Sceletium-type alkaloids from the plant has shown promising antidepressant and anxiolytic activities. In the present study, qualitative and quantitative analyses of the alkaloids in the plant organs were performed during one vegetation season by GC-MS. The alkaloid pattern and total alkaloid content was found to depend strongly on the stage of development and plant organ. The alkaloid content of bulbs was found to be highest during the dormancy period and lowest in sprouting bulbs. The leaves showed the highest alkaloid content during the intensive vegetative growth and lowest during flowering. In total, 13 alkaloids were detected in the methanol extracts of Narcissus cv. Hawera, six Sceletium-type and seven typical Amaryllidaceae alkaloids. Major alkaloids in the alkaloid pattern were lycorine, 6-epi-mesembrenol, mesembrenone, sanguinine, and galanthamine. The leaves of flowering plants were found to have the highest amount of 6-epi-mesembrenol. Mesembrenone was found to be dominant alkaloid in the leaves of sprouting bulbs and in the flowers. Considering the biomass of the plant, the dormant bulbs are the best source of alkaloid fractions enriched with 6-epi-mesembrenol. The flowers and the young leaves can be used for preparation of alkaloid fractions enriched with mesembrenone. The results indicates that Narcissus cv. Hawera is an emerging source of valuable bioactive compounds and its utilization can be extended as a medicinal plant.

Advances on the Amaryllidacea Alkaloids Collected in South Africa, Andean South America and the Mediterranean Basin.

The alkaloids are one of the most represented family of natural occurring biological active compounds. Amaryllidaceae are also very well known for their beautiful flower and are thus used as ornamental plants in historic and public gardens. The Amaryllidacea alkaloids constitute an important group that is subdivided into different subfamilies with different carbon skeletons. They are well known from ancient times for their long application in folk medicine, and in particular, Narcissus poeticus L. was known to Hippocrates of Cos (ca. B.C. 460-370), who treated uterine tumors with a formulate prepared from narcissus oil. To date, more than 600 alkaloids of 15 chemical groups exhibiting various biological activities have been isolated from the Amaryllidaceae plants. This plant genus is diffused in regions of Southern Africa, Andean South America and the Mediterranean basin. Thus, this review describes the chemical and biological activity of the alkaloids collected in these regions in the last two decades as weel those of isocarbostyls isolated from Amaryllidaceae in the same regions and same period.

Supercritical CO2 Extraction of Narcissus poeticus L. Flowers for the Isolation of Volatile Fragrance Compounds.

The flowers of Narcissus poeticus are used for the isolation of valuable fragrance substances. So far, as the majority of these substances consist of volatile and sensitive to heat compounds, there is a need of developing effective methods for their recovery. In this study, freeze-dried N. poeticus inflorescences were extracted with pure supercritical CO2 (SFE-CO2) and its mixture with 5% co-solvent ethanol (EtOH) at 40 °C. Extract yields varied from 1.63% (12 MPa) to 3.12% (48 MPa, 5% EtOH). In total, 116 volatile compounds were identified by GC-TOF/MS in the extracts, which were divided into 20 different groups. Benzyl benzoate (9.44-10.22%), benzyl linoleate (1.72-2.17%) and benzyl alcohol (0.18-1.00%) were the major volatiles among aromatic compounds. The amount of the recovered benzyl benzoate in N. poeticus SFE-CO2 extracts varied from 58.98 ± 2.61 (24 MPa) to 91.52 ± 1.36 (48 MPa) mg/kg plant dry weight (pdw). α-Terpineol dominated among oxygenated monoterpenes (1.08-3.42%); its yield was from 9.25 ± 0.63 (12 MPa) to 29.88 ± 1.25 (48 MPa/EtOH) mg/kg pdw. Limonene was the major monoterpene hydrocarbon; (3E)-hexenol and heneicosanol dominated among alcohols and phenols; dihydroactinidiolide and 4,8,12,16-tetramethyl heptadecan-4-olide were the most abundant lactones; heptanal, nonanal, (2E,4E)-decadienal and octadecanal were the most abundant aldehydes. The most important prenol lipids were triterpenoid squalene, from 0.86 ± 0.10 (24 MPa) to 7.73 ± 0.18 (48 MPa/EtOH) mg/kg pdw and D-α-tocopherol, from 1.20 ± 0.04 (12 MPa) to 15.39 ± 0.31 (48 MPa/EtOH) mg/kg pdw. Aliphatic hydrocarbons (waxes) constituted the main part (41.47 to 54.93%) in the extracts; while in case of a 5% EtOH the percentage of alkanes was the lowest. The fraction of waxes may be removed for the separation of higher value fragrance materials. In general, the results obtained are promising for a wider application of SFE-CO2 for the recovery of fragrance substances from N. poeticus flowers.

GC-MS analysis of Amaryllidaceae and Sceletium-type alkaloids in bioactive fractions from Narcissus cv. Hawera.

RATIONALE: Narcissus cv. Hawera has been found to biosynthesize some Sceletium-type alkaloids with antidepressant and anxiolytic activities. This ornamental plant has been poorly studied as a source of bioactive alkaloids including some contraversive reports on in vitro and intact plants. In this study, a detailed GC-MS characterization of its alkaloid fractions is presented. METHODS: GC-MS was used for the identification of compounds in the alkaloid fractions. Both underivatized and silylated samples were analyzed simultaneously. Elevated plus maze and tail suspension tests were used to assay the anxiolytic and antidepressant activities. Ellman's and MTT-dye reduction assays were used to evaluate the acetylcholinesterase (AChE) inhibitory and cytotoxicity activities, respectively. RESULTS: Of the 29 alkaloids, 13 of Sceletium-type were detected. Two new alkaloids were identified as 2-oxo-mesembrine and 2-oxo-epi-mesembrenol. Lycorine was found as a major compound (43.5%) in the crude silylated methanol extract. After the elimination of lycorine by pre-crystallization, the major alkaloids were 40.8% 6-epi-mesembranol, 16.2% 6-epi-mesembrenol, and 13.8% sanguinine. This fraction showed anxiolytic and antidepressant-like activities as well as potent AChE inhibitory and antineoplastic activities. CONCLUSIONS: Silylation of the alkaloid fractions from Narcissus cv. Hawera provides better separation, structural information, and improved sensitivity for compounds with two and more hydroxyl groups. The lycorine-free alkaloid fraction shows a great potential for further pharmacological studies.

Pseudolycorine N-oxide, a new N-oxide from Narcissus tazetta.

A new N-oxide, Pseudolycorine N-oxide (1) was characterised along with eleven known alkaloids homolycorine (2), O-methylmaritidine (3), 8-O-demethylhomolycorine (4), homolycorine N-oxide (5), lycorine (6), narciclasine (7), pseudolycorine (8), ungeremine (9), 8-O-demethylmaritidine (10), zefbetaine (11) and lycorine N-oxide (12), from Narcissus tazetta. Their structures were established on the basis of spectroscopic data analysis. The extract, fractions and isolated compounds were screened for in vitro cytotoxicity against two human cancer cell lines, human cervical cancer (SiHa) and human epidermoid carcinoma (KB) cells. The study demonstrated the cytotoxic potential of extract and its chloroform and n-butanol fractions. Further, the results revealed the bioactive potential of narciclasine, pseudolycorine and homolycorine alkaloids. However, new N-oxide (1) was not active against these cell lines.

Simultaneous quantification and identification of Amaryllidaceae alkaloids in Narcissus tazetta by ultra performance liquid chromatography-diode array detector-electrospray ionisation tandem mass spectrometry.

Narcissus tazetta is used traditionally for treatment of sores, wounds, skin diseases, cancer in different parts of world. Present study focus on the analysis of amaryllidaceae alkaloids in this plant using an ultra-performance liquid chromatography-diode array detection method. The method was developed for simultaneous quantification of eight Amaryllidaceae alkaloids i.e. pseudolycorine (1), lycorine (2), galanthamine (3), 8-O-demethylhomolycorine (4), N-methylhaemanthidine chloride (5), homolycorine (6), narciclasine (7) and zefbetaine (8) in Narcissus tazetta. The method was validated using a BEH C18 column with linear gradient. Standard calibration curve for the analytes showed good linearity ( r2≥0.999). The method was validated for intra-day (RSDs<0.91%) and inter-day (RSDs<0.65%) precisions and accuracy (recovery 92.2-112.5%). The developed method was successively applied for studying the variation of alkaloids in different parts of Narcissus tazetta, i.e. bulbs, roots, flowers, flower stalks and leaves. The study showed a significant variation of these alkaloids in different parts of the plant. Among the alkaloids under investigation, pseudolycorine had highest content in all the parts. Furthermore, application of the developed method to the identification of phytocomponents allowed the identification of sixteen alkaloids.

Screening of Amaryllidaceae alkaloids in bulbs and tissue cultures of Narcissus papyraceus and four varieties of N. tazetta.

Narcissus spp. are an economically important crop for medicines in relation with the alkaloids production, mainly galanthamine, an acetylcholinesterase inhibitor used for the treatment of Alzheimer's disease. In this article an extensively study of the phytochemistry of both bulbs of different species and varieties of Narcissus grown in Iran and in vitro culture of these plants was investigated. In particular, the Amaryllidaceae alkaloid profile and the galanthamine and lycorine contents in wild bulbs of Narcissus papyraceus (G5) and four varieties of Narcissus tazetta (N. tazetta var. Shahla (G4), N. tazetta var. Shastpar (G1), N. tazetta var. Meskin (G2), N. tazetta var. Panjehgorbei (G3)), growing in Iran are reported. The alkaloid profiles were investigated by GC-MS and LC-MS and the quantitative analysis was performed using GC-MS. In total, thirty alkaloids were identified among them nine alkaloids were observed with the both methods of analysis. The variety Meskin of N. tazetta (G2), showed the highest diversity of alkaloids and the highest content in galanthamine. On this last species (G2) and on N. tazetta var. Shahla (G4), the effects of auxins 2,4-dichlorophenoxyacetic acid (2,4-D), 4-amino-3,5,6-trichloropicolinic acid (Picloram) and naphthalene acetic acid (NAA) at concentrations of 25 and 50 µM were studied on the induction of callus and its capacity to induce organogenesis and alkaloid diversity. All auxins, at the concentrations of 25 and 50 µM, produced calli. Bulblets and roots were formed on calli grown only in the presence of 25 or 50 µM NAA. GC-MS analyses showed the presence of galanthamine and lycorine in calli, roots and bulblets, with all auxins whatever the concentration used while demethylmaritidine and tazettine were found in differentiated tissue cultures cultivated on the medium containing NAA (25 or 50 µM) or in calli initiated with Picloram (50 µM). Precursor 4'-O-methylnorbelladine (MN) of Amaryllidaceae alkaloids feeding was found to significantly improve the accumulation of both galanthamine (82 µg/g DW) and lycorine (1800 µg/g DW) in bulblets of N. tazetta var. Meskin (G2).

Assessment of Human Skin Gene Expression by Different Blends of Plant Extracts with Implications to Periorbital Skin Aging.

Since the skin is the major protective barrier of the body, it is affected by intrinsic and extrinsic factors. Environmental influences such as ultraviolet (UV) irradiation, pollution or dry/cold air are involved in the generation of radical oxygen species (ROS) and impact skin aging and dermal health. Assessment of human skin gene expression and other biomarkers including epigenetic factors are used to evaluate the biological/molecular activities of key compounds in cosmetic formulas. The objective of this study was to quantify human gene expression when epidermal full-thickness skin equivalents were exposed to: (a) a mixture of betaine, pentylene glycol, Saccharomyces cerevisiae and Rhodiola rosea root extract (BlendE) for antioxidant, skin barrier function and oxidative stress (with hydrogen peroxide challenge); and (b) a mixture of Narcissus tazetta bulb extract and Schisandra chinensis fruit extract (BlendIP) for various biomarkers and microRNA analysis. For BlendE, several antioxidants, protective oxidative stress biomarkers and many skin barrier function parameters were significantly increased. When BlendE was evaluated, the negative impact of the hydrogen peroxide was significantly reduced for the matrix metalloproteinases (MMP 3 and MMP 12), the skin aging and oxidative stress biomarkers, namely FBN2, ANXA1 and HGF. When BlendIP was tested for cell proliferation and dermal structural components to enhance the integrity of the skin around the eyes: 8 growth factors, 7 signaling, 7 structural/barrier function and 7 oxidative stress biomarkers were significantly increased. Finally, when BlendIP was tested via real-time RT-PCR for microRNA expression: miR-146a, miR-22, miR155, miR16 and miR21 were all significantly increased over control levels. Therefore, human skin gene expression studies are important tools to assess active ingredient compounds such as plant extract blends to advance dermal hypotheses toward validating cosmetic formulations with botanical molecules.

Fingerprints of flower absolutes using supercritical fluid chromatography hyphenated with high resolution mass spectrometry.

Supercritical fluid chromatography hyphenated with high resolution mass spectrometry (SFC-HRMS) was developed for fingerprint analysis of different flower absolutes commonly used in cosmetics field, especially in perfumes. Supercritical fluid chromatography-atmospheric pressure photoionization-high resolution mass spectrometry (SFC-APPI-HRMS) technique was employed to identify the components of the fingerprint. The samples were separated with a porous graphitic carbon (PGC) Hypercarb™ column (100 mm × 2.1 mm, 3 µm) by gradient elution using supercritical CO2 and ethanol (0.0-20.0 min (2-30% B), 20.0-25.0 min (30% B), 25.0-26.0 min (30-2% B) and 26.0-30.0 min (2% B)) as mobile phase at a flow rate of 1.5 mL/min. In order to compare the SFC fingerprints between five different flower absolutes: Jasminum grandiflorum absolutes, Jasminum sambac absolutes, Narcissus jonquilla absolutes, Narcissus poeticus absolutes, Lavandula angustifolia absolutes from different suppliers and batches, the chemometric procedure including principal component analysis (PCA) was applied to classify the samples according to their genus and their species. Consistent results were obtained to show that samples could be successfully discriminated.

Isolation, Synthesis, and Semisynthesis of Amaryllidaceae Constituents from Narcissus and Galanthus sp.: De Novo Total Synthesis of 2- epi-Narciclasine.

An efficient protocol for the isolation of narciclasine from common Amaryllidaceae bulbs, separation from haemanthamine, and the occurrence of a trace alkaloid, 2- epi-narciclasine, are reported. Attempts to convert natural narciclasine to its C-2 epimer by Mitsunobu inversion or oxidation/reduction sequences were compromised by rearrangement and aromatization processes, through which a synthesis of the alkaloid narciprimine was achieved. The methylation of the 7-hydroxy group of natural narciclasine followed by protection of the 3,4-diol function and oxidation/reduction sequence provided the target C-2 epimer. A de novo chemoenzymatic synthesis of 2- epi-narciclasine from m-dibromobenzene is also described. Haemanthamine and narciprimine were readily detected in the crude extracts of Narcissus and Galanthus bulbs containing narciclasine, and the occurrence of 2- epi-narciclasine as a trace natural product in Galanthus sp. is reported for the first time.

Chemical Characterization of Narcissus poeticus from Sirente -Velino (Apennines - Italy): Galantamine Accumulation and Distribution of Allergenic Compounds in the Flower.

Species of Narcissus (family Amaryllidaceae) are a potential source for large-scale extraction of alkaloids and fragrances. The bulbs typically accumulate a large number of alkaloids, including galantamine, a benzazepine alkaloid proven to be a cholinesterase inhibitor and which is used in the treatment of Alzheimer's disease. The presence of galantamine in N. poeticus L. collected in Abruzzo (Italy) was assessed and several levels of alkaloid were found in all parts of the plant (flower, stem, bulb and root) and not only in the bulb. The amount of galantamine obtained was tested by using two different extraction solvents. Extraction of N. poeticus absolute from the flowers was also performed, as this product is an important floral note in perfumery, and the distribution of allergenic compounds in the coronas and in the tepals was assessed. Moreover, the in vitro propagation of N.:Poeticus was tested as it may be a valuable resource from which to produce biomolecules, as an alternative to chemical synthetic processes.

Chemical constituents of Narcissus tazetta var. chinensis and their antioxidant activities.

Two new flavan derivatives tazettones C-D (1-2), one new ß-coumaranone (tazettone E, 3), one new flavan (tazettone F, 4), and one new phenylpropanoid (tazettone G, 5), together with six known flavonoids (6-11), were isolated from the bulbs of Narcissus tazetta var. chinensis Roem. Their structures were elucidated by spectroscopic analysis. In addition, the structures of 1-3 were confirmed by single crystal X-ray diffraction. All isolated compounds were tested for antioxidant activity by Cell Counting Kit-8 (CCK-8) assay. Compounds 6-8 and 10-11 exhibited potent antioxidant activity against H2O2-induced impairment in human SH-SY5Y neuroblastoma cells at tested concentrations.

Narciclasine - an Amaryllidaceae Alkaloid with Potent Antitumor and Anti-Inflammatory Properties.

The isocarbostyril alkaloid narciclasine, also known as lycoricidinol, was discovered in Narcissus species (Amaryllidaceae) in 1967. A few years later, the 60S subunit of ribosomes, and thus protein biosynthesis, were shown to be directly targeted by narciclasine. Due to its selective and highly potent cytotoxic action on cancer cells, narciclasine was intensively investigated as an antitumor compound both in vitro and in vivo. However, narciclasine did not show a strong pharmacological activity in animal tumor models. During the last decade, new fascinating actions, mechanisms, and targets of narciclasine have emerged. This review intends to present a brief but comprehensive overview of these novel insights. Beneficial therapeutical actions have been reported particularly in brain tumor models. The translation elongation factor eEF1A, which does not only participate in protein biosynthesis but also in the regulation of the actin cytoskeleton, was discovered as new direct target. Moreover, narciclasine was found to trigger actin stress fiber formation via the activation of the small GTPase RhoA. Progress has also been made regarding the pharmacokinetic characterization of the alkaloid. The synthesis of a great number of narciclasine derivatives led to a substantial understanding of its pharmacophore and of the structure-activity relationships. However, an optimized compound did not result from these efforts. Most importantly, a new field of indication has emerged: Narciclasine was proven to exert profound anti-inflammatory actions in vivo. Taken together, there has been a strong advance in the preclinical knowledge about the alkaloid. Nevertheless, narciclasine has not been tested in human clinical trials up to now.

Phenylethanoid and phenylpropanoid glycosides with melanogenesis inhibitory activity from the flowers of Narcissus tazetta var. chinensis.

A methanol extract of the flowers of Narcissus tazetta var. chinensis Roem. (Amaryllidaceae) demonstrated inhibitory effects on melanogenesis in theophylline-stimulated murine B16 melanoma 4A5 cells. From the extract, four new phenylethanoid glycosides, tazettosides A­D (1­4), and a new phenylpropanoid glycoside, tazettoside E (5), were isolated along with 23 known compounds (6­28). Of the isolates, 1 (IC50 = 22.0 µM) and 4 (82.5 µM), 3-methoxy-8,9-methylenedioxy-3,4-dihydrophenanthridine (13, IC50 = 28.5 µM), 5,6-dihydrobicolorine (14, 23.7 µM), tazettine (16, 60.8 µM), benzyl ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranoside (18, 27.8 µM), 2-(3,4-dimethoxyphenyl)ethyl ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranoside (21, 74.6 µM), 3-phenylpropyl ß-D-glucopyranoside (22, 59.0 µM), and cinnamyl ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranoside (24, 88.0 µM) showed inhibitory effects without notable cytotoxicity at the effective concentrations.

HPTLC and GC/MS Study of Amaryllidaceae Alkaloids of Two Narcissus Species.

In this article, we report on the alkaloid profile and dynamic of alkaloid content and diversity in two Narcissus plants at different stages of development. The alkaloid profile of the two Narcissus species was investigated by GC/MS and HPTLC. Fifty eight Amaryllidaceae alkaloids were detected, and 25 of them were identified in the different organs of N. tazetta and N. papyraceus. The alkaloid 3-O-methyl-9-O-demethylmaritidine is tentatively identified here for the first time from the Amaryllidaceae family, and four alkaloids (tazettamide, sternbergine, 1-O-acetyllycorine, 2,11-didehydro-2-dehydroxylycorine) are tentatively identified for the first time in the genus Narcissus. The different organs of the two species analyzed showed remarkable differences in their alkaloid pattern, type of biosynthesis, main alkaloid and number of alkaloids. Lycorine-type alkaloids dominated the alkaloid, metabolism in N. papyraceus, while alkaloids of narciclasine-, galanthamine- and homolycorine-types were found only in the species N. tazetta L.

Jonquailine, a new pretazettine-type alkaloid isolated from Narcissus jonquilla quail, with activity against drug-resistant cancer.

A new alkaloid, belonging to the pretazettine group of Amaryllidaceae alkaloids, was isolated from dried bulbs of Narcissus jonquilla quail and named jonquailine. Its structure, including the absolute configuration, was elucidated using various NMR, ECD and ESI MS techniques. Initial biological evaluation revealed significant antiproliferative effects against glioblastoma, melanoma, uterine sarcoma and non-small-cell lung cancer cells displaying various forms of drug resistance, including resistance to apoptosis and multi-drug resistance. Jonquailine was also found to synergize with paclitaxel in its antiproliferative action against drug-resistant lung cancer cells. The results obtained compared with literature data also showed that the hydroxylation at C-8 is an important feature for the anticancer activity but this seems unaffected by the stereochemistry or the acetalization of the lactol.

In vitro cytotoxicity of some Narcissus plants extracts.

This study compares the chloroform extracts of bulbs and roots of Narcissus papyraceus Ker Gawl. and Narcissus tazetta L. The cytotoxicity of the plant extracts was evaluated against human hepatocellular carcinoma cell line (HEPG2) and colon carcinoma cell line (HCT116) in comparison to doxorubicin. The extracts from the after-flowering (AF) bulbs of N. tazetta L. and N. papyraceus exhibited strong cytotoxic activity against HEPG2 (IC50: 2.2, 3.5 µg mL(-1)) and HCT116 (IC50: 4.2, 3.9 µg mL(-1)) cell lines, respectively. N. tazetta L. bulbs exhibited the least cell viability percentage in HepG-2 cell line (5.32%), while the AF root extracts of N. papyraceus exhibited the least cell viability percentage in HCT116 cell line (4.93%), when applied at a concentration of 50 µg mL(-1), thereby being more active than doxorubicin at the same concentration.

Chemical composition of bioactive alkaloid extracts from some Narcissus species and varieties and their biological activity.

Alkaloid extracts of eight Narcissus (Amaryllidaceae) species and varieties were studied with respect to their acetylcholinesterase (HuAChE) and butyrylcholinesterase (HuBuChE) inhibitory activity and alkaloid patterns. Thirty alkaloids were determined by GC/MS, and twenty-five of them identified from their mass spectra, retention times and retention indexes. Promising HuAChE inhibition activity was demonstrated by six Narcissus taxa and HuBuChE inhibition by N. jonquila cv. Double Campernelle and N. nanus cv. Elka with IC50 values of 24.1 +/- 1.9 microg/mL and 25.1 +/- 1.8 microg/mL, respectively. Two alkaloids were isolated in pure form using preparative TLC and identified as the galanthamine type alkaloid narwedine and the lycorine type alkaloid incartine. Both compounds were tested for their biological activity. They were considered inactive in HuAChE/HuBuChE assays, but showed promising prolyl oligopeptidase inhibition activities with IC50 values of 0.95 +/- 0.12 mM and 0.91 g 0.09 mM, respectively.

A new approach to develop a standardized method for assessment of acetylcholinesterase inhibitory activity of different extracts using HPTLC and image analysis.

A new, validated, sensitive and cheap method for preliminary quantitative evaluation of acetylcholine esterase inhibitory activity is presented. The proposed method combines HPTLC with data analysis by means of image processing software. An in-situ TLC autobiographic method was employed in which regions of the TLC plate which contain acetylcholinesterase inhibitors show up as white spots against the yellow background. Bleaching of the yellow color, caused by substances with acetylcholinesterase inhibitory activity was observed and recorded using a digital camera. ImageJ, JustTLC and Sorbfil, three image processing programs were evaluated for quantitative measurements. For evaluation of the assay efficiency, acetylcholinesterase inhibitory activity of different Amaryllidaceae plant extracts was expressed as Standard Activity Coefficients (SACs), which are relative measures of the activity to the well known acetylcholinesterase inhibitor eserine. We attempted to validate the method according to the ICH guideline. Different statistical data revealed that all image analysis software are able to detect the acetylcholine esterase inhibitory activity at very low concentration levels with the ImageJ program being the best of all three tested software regarding sensitivity, linearity and precision.

Wild daffodils of the section Ganymedes from the Iberian Peninsula as a source of mesembrane alkaloids.

The aim of this work was to perform a detailed study of the alkaloid content of Narcissus triandrus, as well as a complete analysis of the alkaloid profile of 18 wild populations, comprising all the taxa of the section Ganymedes. Through the application of a combination of spectroscopic and chromatographic methods, the isolation and structural elucidation of 3 compounds are reported for the first time from a natural source (2-oxomesembrenone, 7,7a-dehydromesembrenone and 2-oxoepimesembranol), together with the identification of 5 major common mesembrane alkaloids. Additionally, the GC-MS analysis of the alkaloid profile demonstrated the regular presence of mesembranes in all the studied plants, showing mesembrenone as the predominant compound without any typical Amaryllidaceae alkaloid being detected.