Variety Of Alkaloids Research Articles

A thorough evaluation of matrix-free laser desorption ionization on structurally diverse alkaloids and their direct detection in plant extracts.

Alkaloids represent a major group of natural products (NPs), derived from highly diverse organisms. These structurally varied specialized metabolites are widely used for medicinal purposes and also known as toxic contaminants in agriculture and dietary supplements. While the detection of alkaloids is generally facilitated by GC- or LC-MS, these techniques do require considerable efforts in sample preparation and method optimization. Bypassing these limitations and also reducing experimental time, matrix-free laser desorption ionization (LDI) and related methods may provide an interesting alternative. As many alkaloids show close structural similarities to matrices used in matrix-assisted laser desorption ionization (MALDI), they should ionize upon simple laser irradiation without matrix support. With this in mind, the current work presents a systematic evaluation of LDI properties of a wide range of structurally diverse alkaloids. Facilitating a direct comparison between LDI and ESI-MS fragmentation, all tested compounds were further studied by electrospray ionization (ESI). Moreover, crude plant extracts of Atropa belladonna, Cinchona succirubra, and Colchicum autumnale were analyzed by LDI in order to evaluate direct alkaloid detection and dereplication from complex mixtures. Finally, dose-dependent evaluation of MALDI and LDI detection using an extract of Rosmarinus officinalis spiked with atropine, colchicine, or quinine was conducted. Overall, present results suggest that LDI provides a versatile analytical tool for analyzing structurally diverse alkaloids as single compounds and from complex mixtures. It may further serve various potential applications ranging from quality control to the screening for toxic compounds as well as the build up of MS databases. Graphical abstract.

Monoterpene indole alkaloids with acetylcholinesterase inhibitory activity from the leaves of Rauvolfia vomitoria

Seventeen monoterpene indole alkaloids, including seven new alkaloids (1–7) and ten known analogues (8–17), were isolated and identified from the leaves of R. vomitoria. The structures of new alkaloids were elucidated by extensive spectroscopic analysis and single-crystal X-ray diffraction analysis. Rauvomitorine I (1) represents the first example of an unprecedented C22 yohimbine-type monoterpene indole alkaloid featuring a carboxymethyl at C-14. The exceedingly rare vobasenal (2–3) and affinisine oxindole (5–6) framework type alkaloids are first reported from the Rauvolfia genus. Most notably, the structure of vobasenal-type alkaloids (2–3) were first determined by single-crystal X-ray diffraction analyses. Alkaloids 1–17 were tested their cytotoxicity against five cancer cell lines, however, none of them showed significant cytotoxicity at a concentration of 40 μM. All the isolated alkaloids were evaluated their acetylcholinesterase (AChE) inhibitory activities. Alkaloid 3 exhibited significant anti-AChE activity with an IC50 value of 16.39 ± 1.41 μM and alkaloids 8 and 10 showed moderate anti-AChE activities whereas the others (2, 9, 13, and 17) were weak inhibitors. This is the first report of vobasenal-type alkaloids as AChE inhibitors, indicating this type of alkaloids may be important sources for the discovery of new AChE inhibitors. A preliminary structure–activity relationship for AChE inhibitory activities showed the presence of the N-methyl group in vobasenal-type alkaloids may be essential for anti-AChE activity. Further molecular docking studies of vobasenal-type alkaloids revealed that interaction with Trp133 and Trp86 residues at hydrophobic subsite are necessary for the AChE inhibitory activities. This study not only enriches the chemical diversity of alkaloids in Apocynaceae plants but also provides new potential leading compounds and versatile scaffolds for the design and development of new AChE inhibitors to treat AD.

Anti-diabetic potential of mucilage from Hippeastrum vittatum bulbs in streptozotocin-induced diabetic rats

Plants belonging to the family Amaryllidaceae have been the focus of abundant studies thanks to their structurally diverse alkaloids with excellent biological and pharmacological profiles. Nevertheless, the anti-diabetic properties of these plant species have been considered to a lesser extent, in particular those of the subfamily Amaryllidoideae. Hence, in this work, the potential hypoglycaemic effects of the crude mucilage of Hippeastrum vittatum (L'Her.) (syn. Amaryllis vittata) bulbs were examined at 150 and 250 mg/kg using the streptozotocin-induced diabetic rat model. Overall, as compared to the untreated diabetic rats, oral administration of the mucilage at 150 mg/kg significantly ameliorated the induced hyperglycaemia by 45.37% and 61.95% after 2 and 4 h, respectively, whereas the maximum hypoglycemic actions were observed at 250 mg/kg, causing 57.37% and 65.74% reduction in the elevated blood glucose levels after 2 and 3 h, respectively. These effects were also markedly comparable to those of the standard hypoglycaemic drug gliclazide (50 mg/kg, p.o.). As the first report on the anti-hyperglycaemic activity of the genus Hippeastrum, the obtained results enlighten the potential of the water-soluble polysaccharide fraction from this plant and other Amaryllidaceae species for the development of natural hypoglycaemic agents that could be helpful as alternative or complementary therapies for type-2 diabetes.

A yeast platform for high-level synthesis of tetrahydroisoquinoline alkaloids

The tetrahydroisoquinoline (THIQ) moiety is a privileged substructure of many bioactive natural products and semi-synthetic analogs. Plants manufacture more than 3,000 THIQ alkaloids, including the opioids morphine and codeine. While microbial species have been engineered to synthesize a few compounds from the benzylisoquinoline alkaloid (BIA) family of THIQs, low product titers impede industrial viability and limit access to the full chemical space. Here we report a yeast THIQ platform by increasing production of the central BIA intermediate (S)-reticuline to 4.6 g L−1, a 57,000-fold improvement over our first-generation strain. We show that gains in BIA output coincide with the formation of several substituted THIQs derived from amino acid catabolism. We use these insights to repurpose the Ehrlich pathway and synthesize an array of THIQ structures. This work provides a blueprint for building diverse alkaloid scaffolds and enables the targeted overproduction of thousands of THIQ products, including natural and semi-synthetic opioids.

Efficient C-H Amination Catalysis Using Nickel-Dipyrrin Complexes.

A dipyrrin-supported nickel catalyst (AdFL)Ni(py) (AdFL: 1,9-di(1-adamantyl)-5-perfluorophenyldipyrrin; py: pyridine) displays productive intramolecular C-H bond amination to afford N-heterocyclic products using aliphatic azide substrates. The catalytic amination conditions are mild, requiring 0.1-2 mol% catalyst loading and operational at room temperature. The scope of C-H bond substrates was explored and benzylic, tertiary, secondary, and primary C-H bonds are successfully aminated. The amination chemoselectivity was examined using substrates featuring multiple activatable C-H bonds. Uniformly, the catalyst showcases high chemoselectivity favoring C-H bonds with lower bond dissociation energy as well as a wide range of functional group tolerance (e.g., ethers, halides, thioetheres, esters, etc.). Sequential cyclization of substrates with ester groups could be achieved, providing facile preparation of an indolizidine framework commonly found in a variety of alkaloids. The amination cyclization reaction mechanism was examined employing nuclear magnetic resonance (NMR) spectroscopy to determine the reaction kinetic profile. A large, primary intermolecular kinetic isotope effect (KIE = 31.9 ± 1.0) suggests H-atom abstraction (HAA) is the rate-determining step, indicative of H-atom tunneling being operative. The reaction rate has first order dependence in the catalyst and zeroth order in substrate, consistent with the resting state of the catalyst as the corresponding nickel iminyl radical. The presence of the nickel iminyl was determined by multinuclear NMR spectroscopy observed during catalysis. The activation parameters (ΔH‡ = 13.4 ± 0.5 kcal/mol; ΔS‡= -24.3 ± 1.7 cal/mol·K) were measured using Eyring analysis, implying a highly ordered transition state during the HAA step. The proposed mechanism of rapid iminyl formation, rate-determining HAA, and subsequent radical recombination was corroborated by intramolecular isotope labeling experiments and theoretical calculations.

Structural diversity, bioactivities, and biosynthesis of natural diterpenoid alkaloids.

Covering: 2009 to 2018. Diterpenoid alkaloids, originating from the amination of natural tetracyclic diterpenes, are a diverse class of compounds having complex structural features with many stereocenters. The important pharmacological activities and structural complexity of the diterpenoid alkaloids have long interested scientists due to their medicinal uses, infamous toxicity, and unique biosynthesis. Since 2009, 373 diterpenoid alkaloids, assigned to 46 skeletons, have been isolated and identified from plants mostly in the Ranunculaceae family. The names, classes, molecular weight, molecular formula, NMR data, and plant sources of these diterpene alkaloids are collated here. This review will be a detailed update of the naturally occurring diterpene alkaloids reported from the plant kingdom from 2009-2018, providing an in-depth discussion of their diversity, biological activities, pharmacokinetics, toxicity, application, evolution, and biosynthesis.

Stereoselective synthesis of 2,6-disubstituted piperidine alkaloids.

Among the large number of structurally diverse alkaloids, 2,6-disubstituted piperidine and its analogs have often been targeted when exploiting new synthetic techniques perhaps because of their strong pharmacological properties. This review outlines synthetic strategies to build the 2,6-disubstituted piperidine structural motif with a focus on stereochemical control of two substituents at C2 and C6. The key reactions in this process are then classified on the basis of how the piperidine rings were built with specific examples of natural products that control the stereochemical outcomes and their transition states.

Repurposing of plant alkaloids for cancer therapy: Pharmacology and toxicology.

Drug repurposing (or repositioning) is an emerging concept to use old drugs for new treatment indications. Phytochemicals isolated from medicinal plants have been largely neglected in this context, although their pharmacological activities have been well investigated in the past, and they may have considerable potentials for repositioning. A grand number of plant alkaloids inhibit syngeneic or xenograft tumor growth in vivo. Molecular modes of action in cancer cells include induction of cell cycle arrest, intrinsic and extrinsic apoptosis, autophagy, inhibition of angiogenesis and glycolysis, stress and anti-inflammatory responses, regulation of immune functions, cellular differentiation, and inhibition of invasion and metastasis. Numerous underlying signaling processes are affected by plant alkaloids. Furthermore, plant alkaloids suppress carcinogenesis, indicating chemopreventive properties. Some plant alkaloids reveal toxicities such as hepato-, nephro- or genotoxicity, which disqualifies them for repositioning purposes. Others even protect from hepatotoxicity or cardiotoxicity of xenobiotics and established anticancer drugs. The present survey of the published literature clearly demonstrates that plant alkaloids have the potential for repositioning in cancer therapy. Exploitation of the chemical diversity of natural alkaloids may enrich the candidate pool of compounds for cancer chemotherapy and -prevention. Their further preclinical and clinical development should follow the same stringent rules as for any other synthetic drug as well. Prospective randomized, placebo-controlled clinical phase I and II trials should be initiated to unravel the full potential of plant alkaloids for drug repositioning.

Anti-Infective and Anti-Cancer Properties of the Annona Species: Their Ethnomedicinal Uses, Alkaloid Diversity, and Pharmacological Activities.

Annona species have been a valuable source of anti-infective and anticancer agents. However, only limited evaluations of their alkaloids have been carried out. This review collates and evaluates the biological data from extracts and purified isolates for their anti-infective and anti-cancer activities. An isoquinoline backbone is a major structural alkaloid moiety of the Annona genus, and more than 83 alkaloids have been isolated from this genus alone. Crude extracts of Annona genus are reported with moderate activities against Plasmodium falciparum showing larvicidal activities. However, no pure compounds from the Annona genus were tested against the parasite. The methanol extract of Annona muricata showed apparent antimicrobial activities. The isolated alkaloids from this genus including liriodenine, anonaine, asimilobine showed sensitivity against Staphylococcus epidermidis. Other alkaloids such as (+)-Xylopine and isocoreximine indicated significant anti-cancer activity against A549 and K-562 cell lines, respectively. This review revealed that the alkaloids from Annona genus are rich in structural diversity and pharmacological activities. Further exploration of this genus and their alkaloids has potential for developing novel anti-infective and anticancer drugs.

Composition and Bioactivity of Essential Oil From the Leaves of Genipa americana Against the Coconut Mite Aceria guerreronis

Genipa americana L. has a diversity of secondary metabolites, including iridoids, phenolic compounds, and alkaloids. Pharmacological and biological properties have also been reported. This study has aimed to evaluate the chemical composition of the essential oil (EO) obtained from the leaves of G. americana and its bioactivity against Aceria guerreronis Keifer (Acari: Eriophyidae), a serious pest of coconut production areas worldwide. EO from the leaves was extracted and analyzed by Gas Chromatography-Mass Spectrometry and flame ionization detection (GC-MS/FID). For the bioassays, the adult coconut mites were subjected to increasing concentrations of EO. The analyses showed a predominance of sesquiterpenes, followed by monoterpenes, aldehydes, and fatty acids. The EO (LC50 = 0.41 mg mL-1; LC90 = 6.43 mg mL-1) showed toxicity and repellent effects against the coconut mite. The tested EO has the potential to develop as a natural product, with acaricidal activities against A. guerreronis, in order to assist in the control of the coconut mite.

Pyrrolo[2,1-a]isoquinoline scaffold in drug discovery: advances in synthesis and medicinal chemistry.

Pyrrolo[2,1-a]isoquinoline (PIq) is a nitrogen heterocyclic scaffold of diverse alkaloids endowed with several biological activities, including antiretroviral and antitumor activities. Several 5,6-dihydro-PIq (DHPIq) alkaloids, belonging to the lamellarins' family, have proved to be cytotoxic to tumor cells, as well as reversers of multidrug resistance. In this review, we provide an overview of the main achievements over the last decade in the synthetic approaches to access libraries of PIq compounds along with a survey, as comprehensive as possible, of bioactivity, mechanism of action, pharmacophore and structure-activity relationships of synthetic analogs of DHPIq-based alkaloids. The focus is mainly on the potential exploitation of the (DH)PIq scaffold in design and development of novel antitumor drugs.

Ameliorative effect of synthesized silver nanoparticles by green route method from Zingiber zerumbet on mycoplasmal pneumonia in experimental mice

Mycoplasma pneumoniae (MP) can infect both the upper and lower respiratory tracts related diseases and a common cause of community-acquired pneumonia, mostly in young children and adolescents. Zingiber zerumbet (L.) belongs to the family of Zingiberaceae and it is a perennial and aromatic plant that cultivates in subtropical and tropical countries. This plant is traditionally found throughout Southeast Asia and the Pacific region, where it is commonly used in foods, and beverages purposes. Zingiber zerumbet is a valuable foundation of diverse classes of bioactive major compounds that fit to a varied diversity of chemical metabolites, including polyphenols, alkaloids and terpenes. The numerous studies of Z. zerumbet have shown the enormous pharmacological potential of this plant and its derived bioactive compounds in the treatment of various immune-related diseases like inflammation and other chronic diseases. Based on the previous scientific reports, there are no scientific investigations that claim the antipneumonial activity of the Z. zerumbet based silver nanoparticle. Therefore, the aim of the present study was designed and evaluated the anti-pneumonial potential of biosynthesized with Z. zerumbet based silver nanoparticles in mycoplasmal pneumonia in experimental rats.

Evolution of phytochemical diversity in Pilocarpus (Rutaceae)

The evolution of phytochemical diversity and biosynthetic pathways in plants can be evaluated from a phylogenetic and environmental perspective. Pilocarpus Vahl (Rutaceae), an economically important medicinal plant in the family Rutaceae, has a great diversity of imidazole alkaloids and coumarins. In this study, we used phylogenetic comparative methods to determine whether there is a phylogenetic signal for chemical traits across the genus Pilocarpus; this included ancestral reconstructions of continuous and discrete chemical traits. Bioclimatic variables found to be associated with the distribution of this genus were used to perform OLS regressions between chemical traits and bioclimatic variables. Next, these regression models were evaluated to test whether bioclimatic traits could significantly predict compound concentrations. Our study found that in terms of compound concentration, variation is most significantly associated with adaptive environmental convergence rather than phylogenetic relationships. The best predictive model of chemical traits was the OLS regression that modeled the relationship between coumarin and precipitation in the coldest quarter. However, we also found one chemical trait was dependent on phylogenetic history and bioclimatic factors. These findings emphasize that consideration of both environmental and phylogenetic factors is essential to tease out the intricate processes in the evolution of chemical diversity in plants. These methods can benefit fields such as conservation management, ecology, and evolutionary biology.

Identification of structurally diverse alkaloids in Talguenea quinquinervia (gill. Et hook) by liquid chromatography/electrospray ionisation tandem mass spectroscopy and insecticidal activity.

Talguenea quinquinervia has been used in folk medicine and to dye wool, and the main constituents are alkaloids and triterpenes. Identification of these type of compounds in this specie is a necessary step to understand the biological properties. To evaluate the relationship between the chemical composition of root from T. quinquinervia and its insecticidal properties using liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS). Alkaloids were extracted using Soxhlet extraction with methanol. Total extract was partitioned at pH2 and 12 to enrich alkaloid constituents and to remove interferences. The separation of alkaloids in the Talguenea extract was performed on a C18 column using gradient elution and their tandem mass spectra were obtained by quadrupole time-of-flight tandem mass spectrometry (QTOF-MS/MS) to perform accurate mass measurements of fragment ions for the alkaloid constituents. Several types of alkaloids were separated and identified by LC-ESI-MS/MS. The structural assignment of individual alkaloids was performed based on convergence of MS/MS spectral data, pH partitioning behaviour, LC retention behaviour, and accurate mass measurements. The pH partition of the extract provided structural information about unknown alkaloids extracted from T. quinquinervia. A total of 20 compounds were identified and tentatively characterised, and of these 15 alkaloids were reported for the first time in the investigated T. quinquinervia. The chemical profiling of alkaloids in T. quinquinervia with different origins was performed for the first time and provided diagnostic ions for diverse alkaloids in T. quinquinervia. Insecticidal activity observed can be explain by the presence of alkaloid and pentacyclic triterpenes on the fractions assayed.

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).

R. nukuhivensis acts by reinforcing skin barrier function, boosting skin immunity and by inhibiting IL-22 induced keratinocyte hyperproliferation

Rauvolfia nukuhivensis is a well-known plant used for its wide range of beneficial effects in Marquesas islands. It is made up of diverse indole alkaloids and is used as traditional medicine for skin application. The actual mechanism behind the virtue of this plant is still unknown. Hence, in this study we aimed at deciphering the impact of R. nukuhivensis on skin immune system in context of (1) homeostasis, (2) pathogen infection and (3) inflammation. Here we show that R. nukuhivensis enhances cellular metabolic activity and wound healing without inducing cellular stress or disturbing cellular homeostasis. It reinforces the epithelial barrier by up-regulating hBD-1. Nevertheless, in pathogenic stress, R. nukuhivensis acts by preparing the immune system to be reactive and effective directly. Indeed, it enhances the innate immune response by increasing pathogens sensors such as TLR5. Finally, R. nukuhivensis blocks IL-22 induced hyperproliferation via PTEN and Filaggrin up-regulation as well as BCL-2 downregulation. In conclusion, this study provides evidence on the several cutaneous application potentials of R. nukuhivensis such as boosting the immune response or in restoring the integrity of the epithelial barrier.

Symbiotic skin bacteria as a source for sex-specific scents in frogs

Amphibians are known to possess a wide variety of compounds stored in their skin glands. While significant progress has been made in understanding the chemical diversity and biological relevance of alkaloids, amines, steroids, and peptides, most aspects of the odorous secretions are completely unknown. In this study, we examined sexual variations in the volatile profile from the skin of the tree frog Boana prasina and combined culture and culture-independent methods to investigate if microorganisms might be a source of these compounds. We found that sesquiterpenes, thioethers, and methoxypyrazines are major contributors to the observed sex differences. We also observed that each sex has a distinct profile of methoxypyrazines, and that the chemical origin of these compounds can be traced to a Pseudomonas sp. strain isolated from the frog's skin. This symbiotic bacterium was present in almost all individuals examined from different sites and was maintained in captive conditions, supporting its significance as the source of methoxypyrazines in these frogs. Our results highlight the potential relevance of bacteria as a source of chemical signals in amphibians and contribute to increasing our understanding of the role that symbiotic associations have in animals.

Amaryllidaceae and Sceletium alkaloids.

Covering: July 2015 to June 2017. Previous review: Nat. Prod. Rep., 2016, 33, 1318-1343 Recent progress on the isolation, identification, biological activity and synthetic studies of the structurally diverse alkaloids from plants of family Amaryllidaceae has been summarized in this review. In addition, the structurally related alkaloids isolated from Sceletium species are discussed.

Pyrroloindoline cyclization in tryptophan-containing cyclodipeptides mediated by an unprecedented indole C3 methyltransferase from Streptomyces sp. HPH0547.

Diverse bioactive alkaloids with a tryptophan 2,5-diketopiperazine (DKP) core and an annulated structure forming a methylated pyrroloindoline-DKP assembly have been isolated from various microbial sources. However, little is known about their biosynthesis. In this study, a novel indole C3 methyltransferase from Streptomyces sp. HPH0547 was discovered and characterized. Structural elucidation of the products revealed that this enzyme catalyzed unique pyrroloindoline cyclization in tryptophan-containing cyclodipeptides. This is the first C3 methyltransferase reported to catalyze pyrroloindoline cyclization in cyclic dipeptides, which provides a feasible and simple method to access diverse alkaloids.

Discovery and characterisation of lycorine-type alkaloids in Lycoris spp. (Amaryllidaceae) using UHPLC-QTOF-MS.

Lycorine, one of the most common alkaloids in Lycoris spp., is believed to possess pharmacological activity. To discover and identify lycorine-type alkaloids in the crude extracts of bulbs from six Lycoris spp. by ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) detection. A qualitative analytical method with a data mining strategy was utilised. Based on the fragmentation patterns of standards investigated in positive tandem mass spectrometry (MS/MS) mode, the fragmentation rules of lycorine-type alkaloids were summarised. These types of alkaloids were additionally classified as different subtypes based on structural features and MS/MS fragmentation patterns, and the diagnostic ions for characterisation of different subtypes of alkaloids were designated. Thirty-seven lycorine type alkaloids, including 16 previously undescribed compounds, were efficiently screened out and tentatively identified from the crude extracts of six Lycoris spp. Lycoris sprengri may be a preferable species for studying or extracting lycorine-type alkaloids because of elevated relative concentrations and highest diversity of alkaloids. The UHPLC-QTOF-MS and MS/MS data-mining strategy proved useful for the detection and tentative identification of lycorine-type alkaloids in bulbs of Lycoris spp. and could be extended to other Amaryllidaceae genera. The consequent profiling of the lycorine-type alkaloids will be useful in the quality control of raw materials of Lycoris species and the exploration of superior species.