Acetylcholinesterase inhibition studies of alkaloid components from Crinum asiaticum var. sinicum: in vitro assessments by molecular docking and molecular dynamics simulations

Alkaloids are among the most important and best-known secondary metabolites as sources of new drugs from medicinal plants and marine organisms. A phytochemical investigation of the whole plant of Crinum asiaticum var. sinicum resulted in the isolation of seven alkaloids (1-7), including one new dimeric compound, bis-(-)-8-demethylmaritidine (1). Their structures were elucidated using NMR and HR-ESI-MS. The absolute configuration of new compound 1 was established by circular dichroism spectroscopy. All isolated compounds were evaluated for their inhibitory effects on acetylcholinesterase (AChE) activity in vitro. Among them, compound 1 exhibited the most potent AChE inhibition. Moreover, molecular docking and molecular dynamics simulations were carried out for the most active compound to investigate their binding interactions and dynamics behavior of the AChE protein-ligand complex. Therefore, compound 1 may be a potential candidate for effectively treating Alzheimer's disease.

Amaryllidaceae alkaloids from the bulbs of Crinum latifolium L. and their cholinesterase inhibitory activities

Eleven previously undescribed Amaryllidaceae alkaloids, crinalatifolines A-K (1-11), and two first naturally occurring alkaloids, dihydroambelline (12) and N-demethyldihydrogalanthamine (13), were isolated from the bulbs of Crinum latifolium L. Additionally, thirty-seven known alkaloids and one alkaloid artifact were also isolated from this plant species. Their structures and absolute configurations were elucidated using extensive spectroscopic techniques, including IR, NMR, MS, and ECD. Evaluations of the cholinesterase inhibitory activities of most of these compounds were conducted. Among the tested compounds, ungeremine exhibited the highest potency against acetylcholinesterase and butyrylcholinesterase, with the IC50 values of 0.10 and 1.21 μM, respectively. These values were 9.4- and 2.4-fold more potent than the reference drug galanthamine.

Micro-morpho-anatomical transitions at various stages of in vitro development of Crinum malabaricum Lekhak and Yadav: A critically endangered medicinal plant

Crinum malabaricum Lekhak & Yadav is a recently discovered and critically endangered aquatic bulbous plant of the family Amaryllidaceae. It gained attention as a wild source of the acetylcholinesterase inhibiting alkaloid 'galanthamine' used to treat Alzheimer and Parkinson diseases. The bulbs of this plant contain the highest amount of galanthamine among Crinum species. In vitro regeneration systems were developed to produce quality uniform plantlets of C. malabaricum. Bright field light microscopy was used to analyse micro-morpho-anatomical developments taking place in the leaves and roots during in vitro, ex vitro and in vivo transitions of plantlets. Leaves and roots of plants raised in vitro possessed a higher degree of microscopic structural anomalies, such as underdeveloped epicuticular wax deposition, immature and non-functional stomata, more aquiferous parenchyma with a reduced lumen. Roots developed in vitro were characterized by extremely large, uneven cortical cells and reduced intercellular spaces. The vascular tissues were under-developed and only primary vascular tissues were observed. As a result of ex vitro acclimation, there was a significant acceleration in the improvement of tissue systems in leaves and roots. Such plantlets can tolerate elevated temperatures and light under in vivo conditions. Thus, the microscopic evaluation of the structural trajectory in different stages of plantlet development provides an understanding of the acclimation process and structural adaptations, which could help enhance survival of in vitro raised plantlets under ex vitro and in vivo conditions.

ANTIMALARIAL activities and alkaloids from Crinum jagus (Thomps) DANDY

ETHNOPHARMACOLOGICAL RELEVANCE

Locally, among the Yoruba speaking people of South Western, Nigeria, the bulb of Crinum jagus (CJ), known as "ogede odo" is used to treat malaria and as an anthelmintic among other uses.

AIMS OF THIS STUDY

Study aimed at identifying the purified active fractions and constituents of this fraction in an antiplasmodial activity-guided process.

MATERIALS AND METHODS

Antiplasmodial activity-guided fractionation of the bulb and leaf extracts of CJ was investigated against chloroquine-sensitive (NK 65) Plasmodium berghei using 4-day suppressive and prophylactic methods. Molluscicidal activity of the extracts was assayed on adult Biomphalaria glabrata molluscs following WHO test protocols. Fractionation and purification of the active bulb extract was achieved using various chromatographic and spectroscopic techniques to isolate its constituents. Isolated compounds were identified using different spectroscopic methods.

RESULTS AND DISCUSSION

Both extracts had oral median lethal dose (LD₅₀) greater than 5000 mg/kg body weight (b.wt.). The leaf extract had 40% lethality on molluscs while the bulb extract was inactive. The chemosuppressive and prophylactic antimalarial effects of the bulb extract were 76.55 ± 2.76% and 90.49 ± 2.70% (p<0.05) respectively at 1000 mg/kg b. wt. while the reference drugs; chloroquine and pyrimethamine, had 80.26 ± 3.09% and 50.39 ± 6.80% chemosuppressive effects, respectively. Lycorine (1) and crinamine (2) were isolated from the alkaloidal fraction with 71.36 ± 12.54% antiplasmodial activity.

CONCLUSION

The leaf and bulb extracts of Crinum jagus displayed low molluscicidal and moderate antimalarial activities. Lycorine and crinamine were identified from the antiplasmodial alkaloidal active fraction of the bulb.

Lycorine Alkaloid and Crinum americanum L. (Amaryllidaceae) Extracts Display Antifungal Activity on Clinically Relevant Candida Species

Candida species are the main fungal agents causing infectious conditions in hospital patients. The development of new drugs with antifungal potential, increased efficacy, and reduced toxicity is essential to face the challenge of fungal resistance to standard treatments. The aim of this study is to evaluate the in vitro antifungal effects of two crude extracts of Crinum americanum L., a rich alkaloid fraction and lycorine alkaloid, on the Candida species. As such, we used a disk diffusion susceptibility test, determined the minimum inhibitory concentration (MIC), and characterized the components of the extracts using Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (ESI FT-ICR MS). The extracts were found to have antifungal activity against various Candida species. The chemical characterization of the extracts indicated the presence of alkaloids such as lycorine and crinine. The Amaryllidaceae family has a promising antifungal potential. Furthermore, it was found that the alkaloid lycorine directly contributes to the effects that were observed for the extracts and fraction of C. americanum.

Exploring the effect of Crinum latifolia in obesity: possible role of oxidative, angiogenic, and inflammatory pathways

Obesity is a multifaceted disease encompassing deposition of an unnecessary amount of fat which upsurges the possibility of other complications, viz., hypertension and certain type of cancers. Although obesity results from combination of genetic factors, improper diet and inadequate physical exercise also play a major role in its onset. The present study aims at exploring the anti-obesity activity of Crinum latifolia leaf extract in obese rats. The leaves were extracted using hydroalcoholic extraction which was later diluted with water and given to obese rats. The dosing was started from the 4^th week (by oral administration of extract of Crinum latifolia (100 mg/kg and 200 mg/kg) and combination of Crinum latifolia leaf extract 200 mg/kg and orlistat 30 mg/kg) till the 10^th week. Various angiogenic, antioxidant, biochemical, and inflammatory biomarkers were assessed at the end of the study. The obese symptoms were progressively reduced in treatment groups when compared to disease control groups. The angiogenic parameters and inflammatory parameters were consequently reduced in treatment groups. The oxidative parameters superoxide dismutase (SOD) and catalase were gradually increased, while levels of TBARS were reduced in treatment groups showing antioxidant nature of leaf hydroalcoholic extract. The Crinum latifolia leaf extract possesses anti-obesity properties and therefore can be used as a therapeutic option in the management of obesity.

Isolation and Biological Characterization of Homoisoflavanoids and the Alkylamide N-p-Coumaroyltyramine from Crinum biflorum Rottb., an Amaryllidaceae Species Collected in Senegal

Crinum biflorum Rottb. (syn. Crinum distichum) is an Amaryllidaceae plant used in African traditional medicine but very few studies have been performed on this species from a chemical and applicative point of view. Bulbs of C. biflorum, collected in Senegal, were extracted with ethanol by Soxhlet and the corresponding organic extract was purified using chromatographic methods. The pure compounds were chemically characterized by spectroscopic techniques (1D and 2D 1H and 13C NMR, HR MS and ECD) and X-ray analysis. Four homoisoflavonoids (1-4) and one alkylamide (5) were isolated and characterized as 5,6,7-trimethoxy-3-(4-hydroxybenzyl)chroman-4-one (1), as 3-hydroxy-5,6,7-trimethoxy-3-(4-hydroxybenzyl)chroman-4-one (2), as 3-hydroxy-5,6,7-trimethoxy-3-(4-methoxybenzyl)chroman-4-one (3) and as 5,6,7-trimethoxy-3-(4-methoxybenzyl)chroman-4-one (4), and the alkylamide as (E)-N-(4-hydroxyphenethyl)-3-(4-hydroxyphenyl)acrylamide (5), commonly named N-p-coumaroyltyramine. The relative configuration of compound 1 was verified thanks to the X-ray analysis which also allowed us to confirm its racemic nature. The absolute configurations of compounds 2 and 3 were assigned by comparing their ECD spectra with those previously reported for urgineanins A and B. Flavanoids 1, 3 and 4 showed promising anticancer properties being cytotoxic at low micromolar concentrations towards HeLa and A431 human cancer cell lines. The N-p-coumaroyltyramine (5) was selectively toxic to A431 and HeLa cancer cells while it protected immortalized HaCaT cells against oxidative stress induced by hydrogen peroxide. Compounds 1-4 also inhibited acetylcholinesterase activity with compound 3 being the most potent. The anti-amylase and the strong anti-glucosidase activity of compound 5 were confirmed. Our results show that C. biflorum produces compounds of therapeutic interest with anti-diabetic, anti-tumoral and anti-acetylcholinesterase properties.

Crinamine Induces Apoptosis and Inhibits Proliferation, Migration, and Angiogenesis in Cervical Cancer SiHa Cells

Crinum asiaticum is a perennial herb widely distributed in many warmer regions, including Thailand, and is well-known for its medicinal and ornamental values. Crinum alkaloids contain numerous compounds, such as crinamine. Even though its mechanism of action is still unknown, crinamine was previously shown to possess anticancer activity. In this study, we demonstrate that crinamine was more cytotoxic to cervical cancer cells than normal cells. It also inhibited anchorage-independent tumor spheroid growth more effectively than existing chemotherapeutic drugs carboplatin and 5-fluorouracil or the CDK9 inhibitor FIT-039. Additionally, unlike cisplatin, crinamine induced apoptosis without promoting DNA double-strand breaks. It suppressed cervical cancer cell migration by inhibiting the expression of positive regulators of epithelial-mesenchymal transition SNAI1 and VIM. Importantly, crinamine also exerted anti-angiogenic activities by inhibiting secretion of VEGF-A protein in cervical cancer cells and blood vessel development in zebrafish embryos. Gene expression analysis revealed that its mechanism of action might be attributed, in part, to downregulation of cancer-related genes, such as AKT1, BCL2L1, CCND1, CDK4, PLK1, and RHOA. Our findings provide a first insight into crinamine's anticancer activity, highlighting its potential use as an alternative bioactive compound for cervical cancer chemoprevention and therapy.

Anticonvulsant activity of an active fraction extracted from Crinum jagus L. (Amaryllidaceae), and its possible effects on fully kindled seizures, depression-like behaviour and oxidative stress in experimental rodent models

ETHNOPHARMACOLOGICAL RELEVANCE

The leaf extract of Crinum jagus L. (Amaryllidaceae) is widely used in traditional Cameroonian medicine as antiepileptic remedy and for the treatment of convulsion, depression and mood disorders associated with epilepsy.

AIM OF THE STUDY

Hence, this study was conducted to evaluate the effects of an active fraction extracted from the leaves of Crinum jagus against seizures, depression-like behaviour and oxidative stress in pentylenetetrazole (PTZ)-induced kindling in mice.

MATERIALS AND METHODS

Bioactive-guided fractionation of the leaf extract of Crinum jagus by using 70mg/kg PTZ-induced convulsions in mice, afforded a potent anticonvulsant fraction (flavonol kaempferol; C4.4). The effects of C4.4 on 30mg/kg PTZ-induced kindling, kindling-induced depression like-behaviour and oxidative stress was evaluated. Mice were injected PTZ (30mg/kg, i.p.) once every alternate day (48±1h) until the development of kindling. Depression was assessed using tail suspension test and forced swim test while the oxidative stress parameters were estimated in the whole brain at the end of experiments. Mice were submitted to the rota-rod task and open-field test in order to assess any non-specific muscle-relaxant or sedative effects of C4.4. Acute toxicity of C4.4 was also assessed in mice.

RESULTS

Convulsions-induced by 70mg/kg PTZ were strongly antagonized by C4.4. Oral administration of C4.4 significantly increased the latency to myoclonic jerks, clonic seizures as well as generalized tonic-clonic seizures, improved the seizure mean stage and decreased the number of myoclonic jerks in PTZ-kindled mice. The data indicated also that C4.4 significantly reduced the immobility times in the tail suspension test and the forced swim test. This active fraction has also antioxidant properties by decreasing the lipid peroxidation, and augmenting endogenous antioxidant enzymes in brain. C4.4 administered (12.5-50mg/kg) did not alter the locomotion of animals in the open-field or rotarod tests, which suggest a lack of a central depressant effect. The animals did not exhibit any acute toxicity to C4.4 at the therapeutic doses.

CONCLUSION

These results suggest that pretreatment with C4.4 ameliorates convulsions-induced by PTZ, protects mice against kindling development, depression-like behaviour and oxidative stress in PTZ-kindled mice. These finding provides scientific rationale for the use of Crinum jagus extracts for the amelioration of epilepsy observed in traditional medicine in Cameroon.

Hedgehog/GLI-mediated transcriptional activity inhibitors from Crinum asiaticum

The inhibition of the hedgehog (Hh) signaling pathway has emerged as an attractive anti-cancer strategy. As part of our continuing search for natural inhibitors of the Hh/GLI1 signaling pathway, we isolated three alkaloids (1-3) from Crinum asiaticum. Compounds 1 and 3 showed potent Hh/GLI1-mediated transcriptional inhibitory activity and exhibited cytotoxicity against human pancreatic (PANC1) and prostate (DU145) cancer cells. Our data revealed that compounds 1 and 3 clearly inhibited the Hh signaling pathway by down-regulating the expression of GLI-related proteins (PTCH and BCL2) in DU145 cells.

Effects of hippadine on the blood pressure and heart rate in male spontaneously hypertensive Wistar rats

ETHNOPHARMACOLOGICAL RELEVANCE

Hippadine is an alkaloid isolated from Crinum macowanii. Crinum macowanii is used in South Africa to treat oedema, 'heart disease', rheumatic fever, cancer and skin diseases, and belongs to the plant family Amaryllidaceae, assumed to have originated in the South African region. The aim of this study was to evaluate the effect of hippadine, an alkaloid extracted from Crinum macowanii, on the blood pressure (BP) and heart rate (HR) in anaesthetized male spontaneously hypertensive Wistar rats (SHR); and to find out if α1 and⧸or β1 adrenoceptors contribute to its effects.

MATERIALS AND METHODS

Hippadine (2.5-12.5mg/kg), adrenaline (0.05-0.20mg/kg), atenolol (0.5-40mg/kg) and prazosin hydrochloride (100-500µg/kg) were infused intravenously, and the BP and HR measured via a pressure transducer connecting the femoral artery and the PowerLab. Adrenaline increased the systolic, diastolic and mean arterial BP, while hippadine, atenolol and prazosin respectively decreased the systolic, diastolic and mean arterial BP. Increases in HR were observed with both adrenaline and prazosin, while reductions in HR were observed with atenolol and hippadine. Infusion of adrenaline in rats pre-treated with atenolol (30mg/kg), prazosin (400µg/kg), and hippadine (10mg/kg) led to similar increases in BP and HR in all groups. All changes in HR or BP were significant (p<0.05) and dose dependent.

CONCLUSION

Hippadine decreases the BP and HR in SHR, and these effects may be due to α1 and β1 adrenoceptor inhibition.

Alkaloids of Crinum x powellii “Album” (Amaryllidaceae) and their Topoisomerase Inhibitory Activity

The alkaloids lycorine, 1-O-acetyllycorine and ismine were isolated from the basic dichloromethane- soluble fraction of Crinum x powellii “Album” bulbs. The alkaloid structures were established by physical and spectroscopic analyses, including 1D NMR techniques and GCMS analysis. The three alkaloids are reported for the first time for this hybrid. Additionally, the three alkaloids isolated were tested against a mechanism-based bioassay utilizing genetically engineered mutants of the yeast Saccharomyces cerevisiae strains RAD+, RAD52Y and RS321 where lycorine was the only alkaloid that displayed moderate topoisomerase I inhibitory activity.

Anti-tuberculosis activities of the crude methanolic extract and purified fractions of the bulb of Crinum jagus

Tuberculosis (TB) is of great public health burden globally especially in developing countries of Africa and Asia . Current TB regimen involves multiple therapies and of long duration leading to poor patient adherence. There is also the challenge of multidrug resistant TB. Hence, there is a need for discovery of new anti- TB drugs. This study was designed to investigate the in -vitro activity of the crude methanolic extract and chromatographic fractions of the bulb of Crinum jagus against Mycobacterium tuberculosis isolates. The extracts were screened for anti- TB activity against three different M. tuberculosis isolates and a drug susceptible reference strain H37Rv using Lowenstein Jensen (L-J) medium and Middlebrook 7H10agar. The crude extract was prepared using soxhlet extraction apparatus while the purified fractions were obtained by column chromatography. The two media were inoculated with M. tuberculosis strains, after which the crude and purified extracts were added. After 4-6 weeks incubation, colony forming units were counted and percentage inhibition calculated. The crude extract and the purified fractions showed inhibitory activity on all the isolates tested including the reference strain. Fraction 3 showed the highest inhibitory percentage (86%) among the extracts. At a concentration of 1.0mg/ml, the percentage inhibition of fraction 3, rifampicin and isoniazid against M. tuberculosis strain 3 were 83%, 95% and 86% in L-J medium respectively while 86%, 96% and 89% were obtained respectively in Middle brook medium. Results showed that the crude methanolic extract and the purified fractions of the bulb of Crinum jagus exhibited anti-mycobacterial activity which is an indication of promising potential of this plant for the development of anti-tuberculosis agent.

Extracts of Crinum latifolium inhibit the cell viability of mouse lymphoma cell line EL4 and induce activation of anti-tumour activity of macrophages in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Crinum latifolium L. (CL) leaf extracts have been traditionally used in Vietnam and are now used all over the world for the treatment of prostate cancer. However, the precise cellular mechanisms of the action of CL extracts remain unclear.

AIM OF THE STUDY

To examine the effects of CL samples on the anti-tumour activity of peritoneal murine macrophages.

MATERIALS AND METHODS

The properties of three extracts (aqueous, flavonoid, alkaloid), one fraction (alkaloid), and one pure compound (6-hydroxycrinamidine) obtained from CL, were studied (i) for redox capacities (DPPH and bleaching beta-carotene assays), (ii) on murine peritoneal macrophages (MTT assay) and on lymphoma EL4-luc2 cells (luciferine assay) for cytotoxicity, (iii) on macrophage polarization (production of ROS and gene expression by PCR), and (iv) on the tumoricidal functions of murine peritoneal macrophages (lymphoma cytotoxicity by co-culture with syngeneic macrophages).

RESULTS

The total flavonoid extract with a high antioxidant activity (IC50=107.36 mg/L, DPPH assay) showed an inhibitory action on cancer cells. Alkaloid extracts inhibited the proliferation of lymphoma cells either by directly acting on tumour cells or by activating of the tumoricidal functions of syngeneic macrophages. The aqueous extract induced mRNA expression of tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin 6 (IL-6) indicating differentiation of macrophages into pro-inflammatory M1 polarized macrophages. The total flavonoid, alkaloid extracts and an alkaloid fraction induced the expression of the formyl peptide receptor (FPR) on the surface of the polarized macrophages that could lead to the activation of macrophages towards the M1 phenotype. Aqueous and flavonoid extracts enhanced NADPH quinine oxido-reductase 1 (NQO1) mRNA expression in polarized macrophages which could play an important role in cancer chemoprevention. All the samples studied were non-toxic to normal living cells and the pure alkaloid tested, 6-hydroxycrinamidine, was not active in any of the models investigated.

CONCLUSIONS

Our results indicate that CL extracts and alkaloid fraction (but not pure 6-hydroxycrinamidine) inhibit the proliferation of lymphoma cells in multiple pathways. Our results are in accordance with traditional usage and encourage further studies and in vivo assays.

Comprehensive study of alkaloids from Crinum asiaticum var. sinicum assisted by HPLC-DAD-SPE-NMR

A comprehensive study of the alkaloids presentin the leaves of Crinum asiaticum var. sinicum, assisted by HPLC-SPE-NMR, led to the characterization of 21 compounds of similar polarity on an analytical scale. Thirteen of these were isolated for further structural confirmation. Seven are proved to be new, namely, (+)-siculine (4), 1-epijosephinine (11), 7-methoxycrinamabine (10), 2-O-acetylcrinamabine (16), 3-O-acetyl-8-O-demethylmaritidine (17), 2-O-acetylbulbisine (18), and 1-O-acetylbulbisine (19). In addition, dihydrovittatine (6) and 8-O-demethyloxomaritidine (21) were isolated for the first time from Nature, although they have been prepared previously as synthetic products. Their structures were established by spectroscopic analysis.

Antibacterial agents from the leaves of Crinum purpurascens herb (Amaryllidaceae)

BACKGROUND

Typhoid fevers and urogenital infections continue to be serious health problems in developing countries. In our search for therapeutic agents from natural sources with potential for the treatment of typhoid fevers and urogenital infections, extract and compounds were obtained from Crinum purpurascens and tested.

METHODS

Two alkaloids (4,5-ethano-9,10-methylenedioxy-7-phenanthridone or hippadine (1) and 4,5-ethano-9-hydroxy-10-methoxy-7-phenanthridone or pratorimine (2)) and one steroid (â-D-glucopyranoside of sitosterol (3)) were isolated from the CH(2)Cl(2)/MeOH (1:1) leaf extract of Crinum purpurascens and screened for antibacterial activity using both agar diffusion and broth dilution techniques.

RESULTS

For the CH(2)Cl(2)/MeOH extract, the MIC values obtained were 3 mg/ml (against P. aeruginosa), 4 mg/ml (against E. coli, K. pneumoniae and S. aureus) and 6 mg/ml (against S. typhi and S. paratyphi B), whereas the MBC values varied between 7 and 12 mg/ml. For compound 1, the MIC values varied between 200 and 250 µg/ml, whereas the MBC value was 300 µg/ml against all the bacteria strains used. Compound 2 did not show any antimicrobial activity against these bacteria strains. For compound 3, the MIC values varied between 250 and 300 µg/ml, whereas the MBC values were 300 µg/ml (against S. typhi and S. paratyphi B) and > 300 µg/ml (against the other bacteria strains).

CONCLUSION

These data suggest that C. purpurascens leaf extract contains antibacterial agents which could be used in the treatment of typhoid fevers and urogenital infections.

Analysis of Amaryllidaceae alkaloids from Crinum by high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry

A high-performance liquid chromatography/electrospray ionization multi-stage tandem mass spectrometry (HPLC/ESI-MS(n)) method was developed to analyze two structurally related groups of Amaryllidaceae alkaloids (AmAs), crinane- and tazettine-type alkaloids, in the species Crinum latifolium and C. asiaticum, as well as different organs of C. latifolium. In ESI-MS(n) spectra of the two types of alkaloids, characteristic fragmentation reactions were observed that allowed us to determine and differentiate them. Based on the fragmentation rules of reference standards, crinane-type alkaloids displayed concurrent neutral loss of C(2)H(5)N (43 u) and C(2)H(6)N (44 u) as well as characteristic ions of m/z 213 and 211, whereas tazettine-type alkaloids exhibited neutral loss of C(3)H(7)N (57 u) [or C(2)H(5)N (43 u), C(3)H(7)NO (73 u)] from the [M+H](+) and [M+H-H(2)O](+) ions. These were supported by quadrupole time-of-flight (Q-Tof)-MS/MS analysis. The chemical complexity of the mixture was resolved by profiling. The compositions of the main crinane- and tazettine-type alkaloids in the above-mentioned species and organs were also compared. Overall, 28 AmAs comprising 14 crinane-type and 14 tazettine-type alkaloids were identified and studied by MS. Among them, 14 AmAs were tentatively characterized from the two species for the first time. This method allowed a rapid analysis of alkaloid distribution and composition of Crinum species, and may also be used for quality control and screening of extracts designated for pharmaceutical application.

Anti-inflammatory activity of Crinum asiaticum Linne var. japonicum extract and its application as a cosmeceutical ingredient

Crinum asiaticum Linne var. japonicum has long been used as a rheumatic remedy, as an anti-pyretic and as an anti-ulcer treatment, and for the alleviation of local pain and fever in Korea and Malaysia. In order to investigate the possibility of Crinum asiaticum Linne var. japonicum extract as a cosmetic ingredient, we measured its anti-inflammatory effect by its inhibition of iNOS (inducible nitric oxide synthase) and the release of PGE2, IL-6, and IL-8. We also measured its anti-allergic effect by its inhibition of beta-hexosamidase release. An HPLC experiment after extraction with 95% EtOH at pH 3.5 showed that Crinum asiaticum Linne var. japonicum was mainly composed of lycorine (up to 1%), a well-known immunosuppressor. The content of lycorine varied, depending on the type of plant tissue analyzed and the extraction method. In an anti-inflammatory assay for inhibition of nitric oxide formation on lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells, the ethanol extract of Crinum asiaticum showed an inhibitory activity of NO production in a dose-dependent manner (IC50 = 58.5 microg/ml). Additional study by RT-PCR demonstrated that the extract of Crinum asiaticum significantly suppressed the expression of the iNOS gene. Moreover, the extract of Crinum asiaticum did not show any cytotoxicity, but did show a cell proliferation effect against LPS (a 10 approximately 60% increase in cell viability). In an assay to determine inhibition of the H2O2-activated release of PGE2, IL-6, and IL-8 in human normal fibroblast cell lines, the release of PGE2 and IL-6 was almost completely inhibited above concentrations of 0.05% and 1%, respectively. Moreover, the release of IL-8 was completely inhibited over the entire range of concentration (>0.0025%). In order to investigate the skin-sensitizing potentials of the extract of Crinum asiaticum, a human clinical test was performed after repeated epicutaneous 48-h applications under an occlusive patch (RIPT). The repeated and single cutaneous applications of Crinum asiaticum Linne var. japonicum extract under the occlusive patch did not provoke any cumulative irritation and sensitization reactions. The result showed that the extract of Crinum asiaticum Linne var. japonicum has a sufficient anti-inflammatory effect. Therefore, Crinum asiaticum Linne var. japonicum extract may be useful for development as an ingredient in cosmetic products.

A new tyrosinase inhibitor from Crinum yemense as potential treatment for hyperpigmentation

A new pyran derivative, 6-hydroxy-2H-pyran-3-carbaldehyde, has been isolated from the methanolic extract of Crinum yemense along with the known alkaloid haemanthamine, benzoic acid and 1,1'-bis(1,1'-carboxyethyl) ether which is isolated from a natural source for the first time. Structure elucidation of these compounds based on spectroscopicevidences. The pyran derivative was found to be a tyrosinase inhibitor more potent than kojic acid.

Crinamine from Crinum asiaticum var. japonicum inhibits hypoxia inducible factor-1 activity but not activity of hypoxia inducible factor-2

In a search for natural product inhibitors of hypoxia inducible factor-1 (HIF-1) function, crinamine (1), a crinane type alkaloid, showed potent dose dependent inhibition (IC50 = 2.7 microM) of HIF-1alpha in a cell-based reporter gene assay. Crinamine (1) was isolated from the aerial parts of Crinum asiaticum var. japonicum together with lycorine (2), norgalanthamine (3) and epinorgalanthamine (4). The other components (2-4) showed no significant inhibition of HIF-1alpha induced transcriptional activity.

Preparation of secolycorines against acetylcholinesterase

5,6-Secolycorines possessing a 5,6-dihydrophenanthridine skeleton were facilely prepared from lycorine through chemical transformations, mainly including N-alkylation, Hofmann degradation type reaction, reductive cleavage of trichloroethylcarbonyl moiety, and hydrogenation. Several secolycorine derivatives showed potent inhibitory activity against acetylcholinesterase with the IC(50) value at micromolar range and are more potent than galanthamine.

Bio-guided isolation of cholinesterase inhibitors from the bulbs of

In a search for potential acetylcholinesterase (AChE) inhibitors, the ethanol extract of the bulbs of Crinum x powellii (Amaryllidaceae) was found to demonstrate a marked inhibition of this enzyme. Using a bio-guided isolation strategy, linoleic acid ethyl ester has been identified as the compound responsible for this inhibition. Three other molecules - the alkaloid hippadine, the glycosylated benzyl alcohol derivative calleryanin and 4'-hydroxy-7-methoxyflavan - were also isolated and characterized for the first time from Crinum x powellii. The structures of these compounds were elucidated by spectrometric methods including EI, D/CI mass spectrometry, (1)H, (13)C and 2D NMR experiments. Linoleic acid was also found to inhibit AChE.

Augustamine type alkaloids from Crinum kirkii

Sixteen more Amaryllidaceae alkaloids have been isolated from bulbs of Crinum kirkii Baker of which noraugustamine and 4a,N-dedihydronoraugustamine are hitherto unknown. Their structures and those of earlier known alkaloids have been established by physical and spectroscopic analysis. Application of 2D NMR techniques was used for complete characterization of the alkaloids as well as of 3-O-acetylsanguinine. 1,2-Diacetyllycorine and 3-O-acetylsanguinine showed activity against Trypanosoma brucci rhodesiense, the parasite associated with sleeping sickness. 3-O-acetylsanguinine also showed some activity against Trypanosoma cruzi.

Alkaloids from the bulbs of Crinum bulbispermum

Two new alkaloids, namely 8-hydroxylycorin-7-one and 2-deoxylycorine were isolated from Crinum bulbispermum along with the known compounds vittatine, 11-hydroxyvittatine and hippamine.

Choline esterase inhibitory properties of alkaloids from two Nigerian Crinum species

The bulbs of Crinum jagus and Crinum glaucum are used in traditional medicine in southern Nigeria for memory loss and other mental symptoms associated with ageing. Alkaloidal extracts of bulbs from each species showed inhibition of acetylcholinesterase, an activity exploited therapeutically to raise the depressed levels of acetylcholine in the brain associated with Alzheimer's disease. Using the in situ bioautographic test method for enzyme inhibition, a number of alkaloids were isolated and their activity quantified using the Ellman spectrophotometric test. The most active alkaloids isolated were hamayne (IC50 250 microM) and lycorine (IC50 450 microM) whilst other alkaloids were comparatively inactive with haemanthamane giving 3% inhibition and crinamine giving 4.4% inhibition at 50 mg ml(-1) (174 microM). These contrast with the positive control physostigmine which gave IC50 of 0.25 microM. Cholinesterase activity appears to be associated with the presence of two free hydroxy groups in this structural type of Amaryllidaceae alkaloid.

New crinine-type alkaloids with inhibitory effect on induction of inducible nitric oxide synthase from Crinum yemense

The 80% aqueous methanolic extract from the bulbs of Crinum yemense showed a potent inhibitory effect on nitric oxide production in lipopolysaccharide-activated macrophages. Three new crinine-type alkaloids, yemenines A (1), B (2), and C (3), were isolated from the herbal extract together with six known alkaloids. The absolute configurations of 1-3 were determined on the basis of chemical and physicochemical evidence. The effects of the isolated alkaloids on nitric oxide production in lipopolysaccharide-activated macrophages were examined, and several alkaloids, e.g. 1, (+)-bulbispermine (6), (+)-crinamine (7), (+)-6-hydroxycrinamine (8), and (-)-lycorine (9), showed inhibitory effects on nitric oxide production and induction of inducible nitric oxide synthase.

Alkaloid production in Crinum moorei cultures

The alkaloids cherylline (1), crinamidine (2), crinine (3), epibuphanisine (4), lycorine (5), powelline (6), undulatine (7), 1-epideacetylbowdensine (8), and 3-O-acetylhamayne (9) were identified in the in vitro propagated bulblets of Crinum moorei. In addition, crinine, powelline, and undulatine were detected in the solidified Murashige and Skoog (MS) medium. The identity of the alkaloids was confirmed by comparing retention times and mass spectra with known samples. Light, as well as benzyladenine (BA) and charcoal supplementation of the tissue culture medium, influenced the levels of specific alkaloids in both the bulblets and media.

Preliminary structure-antiangiogenic activity relationships of 4-senecioyloxymethyl-6,7-dimethoxycoumarin

Through a systematic modification of the novel angiogenesis inhibitor 4-senecioyloxymethyl-6,7-dimethoxycoumarin (1) we found that a 6,7-dimethoxy moiety is important for bioactivity of 1. Replacement of the lactone functionality in coumarin 1 by an amide decreased its activity. By substitution of the senecioyl chain with various cinnamoyl groups we discovered 6d, bearing a 4-methoxycinnamoyl instead of senecioyl side chain, with inhibitory activity in HUVEC tube formation assay enhanced by one order of magnitude compared to 1. We have also synthesized compound 12, an analogue of 6d, with equipotency and improved water solubility.

The anti-allergic effects of Crinum glaucum aqueous extract

The aqueous extract of Crinum glaucum was investigated for its effects on rat passive cutaneous anaphylactic reaction, rat peritoneal mast cell degranulation and allergic bronchoconstriction in the guinea pig. The extract demonstrated a significant (p < 0.05) reduction in area of dye leakage. The extract, administered for five days, inhibited mast cell degranulation of normal and passively sensitized rats induced by dextran and antigen. Allergic bronchoconstriction in actively sensitized guinea pigs was inhibited by the extract. The effects of the extract observed were comparable to those of sodium cromoglycate. These results substantiate the efficacy of the extract in the treatment of asthma, in traditional medicine.