Narciclasine-4-O-ß-D-xylopyranoside, a new narciclasine glycoside from Zephyranthes minuta.

A new narciclasine glycoside, narciclasine-4-O-ß-D-xylopyranoside (1) was characterised along with four known alkaloids pancratistatin (2), 1-O-(3-hydroxybutyryl) pancratistatin (3), vittatine (4), 9-O-demethylgalanthine (5) from Zephyranthes minuta. Their structures were established on the basis of spectroscopic data analysis. The in vitro cytotoxic study of extract, fractions and isolated compounds against two human cancer cell lines (KB and SiHa) indicated the potential activity of extract and n-butanol fraction due to presence of active alkaloids pancratistatin, 1-O-(3-hydroxybutyryl) pancratistatin, lycorine and haemanthamine.

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.

Antifilarial activity of diterpenoids from Taxodium distichum.

BACKGROUND: Lymphatic filariasis caused by Wuchereria bancrofti, Brugia malayi and B. timori, is a debilitating disease with an adverse social and economic impact. The infection remains unabated in spite of treatment with existing antifilarial drugs diethylcarbamazine (DEC) and ivermectin which are chiefly microfilaricides. There is therefore, need for macrofilaricides, embryostatic agents and better microfilaricides. In the present study we explored the antifilarial potential of crude extract and its molecular fractions of the plant Taxodium distichum using in vitro assay systems and rodent models of B. malayi infection. METHODS: Ethanolic extract (A001) of aerial parts of T. distichum was solvent fractionated and sub-fractionated. Four molecules, 3-Acetoxylabda-8(20), 13-diene-15-oic acid (K001), Beta-sitosterol (K002), labda-8(20),13-diene-15-oic acid (K003) and Metasequoic acid A (K004) were isolated from the fractions and their structure determined by spectroscopic analysis. The extract, subfractions and molecules were evaluated for antifilarial activity against B. malayi by 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) reduction and motility assays in vitro and in two animal models, Meriones unguiculatus and Mastomys coucha, harbouring B. malayi infection. RESULTS: A001 was effective in killing microfilariae (mf) and adult worms in vitro. The diterpenoid K003 produced 100 % reduction in motility of both mf and adult worms and > 80 % inhibition in MTT reduction potential of adult female worms. In B. malayi-M. unguiculatus model, A001 killed all the adult worms in > 80 % of infected animals. K003 was embryostatic (> 95 %) in this model. In the B. malayi-M. coucha model, K003 killed ~54 % of adult worms (macrofilaricidal activity) and rendered > 36 % female worms sterile; it also stopped any further rise in microfilaraemia after day 42 post-initiation of treatment. CONCLUSION: Ethanolic extract of aerial parts of the plant T. distichum possesses potent antifilarial activity and the active principle was localised to K003 which showed significant macrofilaricidal activity and late suppression of peripheral microfilaraemia and some embryostatic activity. These findings indicate that labdane diterpenoid molecule(s) may provide valuable leads for design and development of new macrofilaricidal agent(s). To the best of our knowledge, this is the first report on antifilarial efficacy of products from the plant T. distichum.

Zephgrabetaine: a new betaine-type amaryllidaceae alkaloid from Zephyranthes grandiflora.

Zephgrabetaine (1), a new betaine type Amaryllidaceae alkaloid, along with seven known alkaloids, lycorine, galanthine, lycoramine, hamayne, haemanthamine, tortuosine, and ungeremine were isolated from the bulbs of Zephyranthes grandiflora and their structures elucidated by spectroscopic data analysis. The isolated alkaloids were tested for in vitro cytotoxic activities against two cell lines, C-6 (rat glioma cells) and CHO-K1 (Chinese hamster ovary cells). A dose dependent cytotoxic effect was exhibited by all the alkaloids on these two cancer cell lines with prominent activity of lycorine and haemanthamine.

Simultaneous quantification of Amaryllidaceae alkaloids from Zephyranthes grandiflora by UPLC-DAD/ESI-MS/MS.

A rapid, simple and sensitive ultra performance liquid chromatography-diode array detection method (UPLC-DAD) was developed and validated for quantification of four biologically important Amaryllidaceae alkaloids viz. lycoramine, hamayne, haemanthamine and tortuosine in Zephyranthes grandiflora. The method employed BEH C(18) column (2.1mm×100mm, 1.7µm particle size) with linear gradient elution of acetonitrile and water (0.05% formic acid) in a flow rate of 0.3mL/min and at λ(max) 280nm. Standard calibration curve for the analytes were linear (r(2)≥0.9999), precise (intra-day RSDs<1.33% and inter-day RSDs<2.67%) and accurate (97.8-105.3%). The developed method was applied to the quality assessment of samples collected during different seasons and showed significant variation with an optimum amounts of these alkaloids in rainy season. The method was also applied for identification of Amaryllidaceae alkaloids in the plant and overall, seventeen Amaryllidaceae alkaloids of different structural types lycorine, haemanthamine, galanthamine, narciclasine were characterised. This study provides a qualitative and quantitative method for analysis of Amaryllidaceae alkaloids.