New stilbenes and phenolic constituents from the rhizomes of Belamcanda chinensis

A pair of stilbenes with γ-lactam unit [(+)-1 and (-)-1], a new phenolic glucoside (2), and a new isoflavone glucoside (3), together with two known compounds (4-5) were isolated from the rhizomes of Belamcanda chinensis. The chemical structures of the undescribed compounds were elucidated on the basis of detailed spectroscopic analyses. Compounds 1, 4, and 5 (10 μM) exhibited anti-inflammatory activities with inhibition rates of 30.46%, 60.34%, and 37.91%, respectively, against the NF-κB signaling pathway.

Induction of apoptosis by Eleutherine bulbosa (Mill.) Urb. bulb extracted under optimised extraction condition on human retinoblastoma cancer cells (WERI-Rb-1)

ETHNOPHARMACOLOGICAL RELEVANCE

The bulb of Eleutherine bulbosa (Mill.) Urb. is an indigenous medicinal plant traditionally used among Dayak people for the management of diabetes, breast cancer, hypertension, stroke, and fertility problems in women. The bulb has been reported with a potent cytotoxic potential but with limited underlying mechanisms.

AIM OF THE STUDY

This study aimed to investigate the cytotoxic properties of E. bulbosa ethanolic bulb extracted under optimised extraction condition on retinoblastoma cancer cells (WERI-Rb-1) through in vitro cell culture bioassays. The optimised extraction condition has been determined in the previous reports.

MATERIALS AND METHODS

Cytotoxic assay was analysed through MTT assay. Comparison between non-optimised and optimised extraction condition from E. bulbosa ethanolic bulb extract was evaluated. Morphological assessment of apoptotic cells was conducted through acridine orange propidium iodide (AOPI) staining using fluorescence microscopy. Apoptosis assay was carried out through Annexin V-FITC and cell cycle analysis through PI staining. The effect of varying concentrations (IC₂₅, IC₅₀, IC₇₅) of the optimised E. bulbosa ethanolic bulb extract was observed. The mRNA expression was also conducted to confirm the underlying mechanism.

RESULTS

The optimised E. bulbosa ethanolic bulb extract markedly suppressed the proliferation of retinoblastoma cancer cells significantly with an IC₅₀ value of 15.7 μg/mL as compared to non-optimised extract (p < 0.01). Fluorescence microscopy revealed that retinoblastoma cancer cells manifested early features of apoptosis-like membrane blebbing, chromatin condensation and formation of apoptotic bodies in a dose-dependent manner. The number of apoptotic cells were greatly observed in early and late apoptosis through Annexin V-FITC and the extract also induced cell arrestment as compared to the untreated group. The apoptosis was confirmed with the upregulation of Bax, Bad, p53, Caspase 3, Caspase 8, and Caspase 9 genes meanwhile, Bcl-2, BcL-xL, Nrf-2, and HO-1 genes were downregulated.

CONCLUSION

The optimised E. bulbosa ethanolic bulb extract induced a significant cell death and cell cycle arrestment on retinoblastoma cancer cells. It could be suggested that the induction of apoptosis in retinoblastoma cancer cells may be due to the synergistic effect of the bioactive compounds extracted under optimised extraction condition. Our findings indicated that E. bulbosa bulb could be promising chemotherapeutic potential to treat retinoblastoma cancer cells.

Eleutherine bulbosa (Mill.) Urb. Bulb: Review of the Pharmacological Activities and Its Prospects for Application

Natural product is an excellent candidate for alternative medicine for disease management. The bulb of E. bulbosa is one of the notable Iridaceae family with a variety therapeutic potential that is widely cultivated in Southeast Asia. The bulb has been used traditionally among the Dayak community as a folk medicine to treat several diseases like diabetes, breast cancer, nasal congestion, and fertility problems. The bulb is exceptionally rich in phytochemicals like phenolic and flavonoid derivatives, naphthalene, anthraquinone, and naphthoquinone. The electronic database was searched using various keywords, i.e., E. bulbosa, E. americana, E. palmifolia, E. platifolia, and others due to the interchangeably used scientific names of different countries. Scientific investigations revealed that various pharmacological activities were recorded from the bulb of E. bulbosa including anti-cancer, anti-diabetic, anti-bacterial, anti-fungi, anti-viral, anti-inflammatory, dermatological problems, anti-oxidant, and anti-fertility. The potential application of the bulb in the food industry and in animal nutrition was also discussed to demonstrate its great versatility. This is a compact study and is the first study to review the extensive pharmacological activities of the E. bulbosa bulb and its potential applications. The development of innovative food and pharma products from the bulb of E. bulbosa is of great interest.

Activity and Toxicity of Eleutherine palmifolia (L.) Merr. Extract on BALB/c Mice Colitis-Associated Colon Cancer Model

OBJECTIVE

Eleutherine palmifolia (L.) Merr. extract (EPE) containing isoliquiritigenin and oxyresveratrol is believed to be an anticancer agent. This study evaluates colon histopathology, TNF-α, TGF-β, and hepatotoxicity on BALB/c mice colitis-associated colon cancer (CAC) model treated with EPE.

METHODS

In vivo study was performed on BALB/c mice CAC model induced by 10 mg/kgBW AOM on the first day followed by administration that each cycle consisted of 5% DSS in water for seven days and regular water for seven days. The indicators of the formation of CAC were observed by a fecal occult blood test (FOBT) and serum amyloid α (SAA) test. The treatment was conducted once a week started from the seventh week up to the twentieth week with six treatment groups: I was administrated by regular water only (negative control), II was administrated by AOM and DSS only (positive control), III was administrated by doxorubicin,  IV-VI were treated by EPE (0.25 mg/kg BW, 0.50 mg/kg BW, and 1.00 mg/kg BW) respectively. The colon and liver's histopathology was observed using hematoxylin-eosin (HE) staining, TNF-α with immunohistochemistry (IHC), and level measurement of TGF-β colon with ELISA reader. The data were used one-way ANOVA followed by post hoc as statistical analysis.

RESULTS

The administration of EPE increased the expression of TNF-α, the total of goblet cells of the colon, and decreased the level of TGF-β. Administration of EPE 0.50 mg/20g BW decreased a liver histopathological score but induced a histopathological alteration of the liver at a dose of 1.00 mg/20g BW.

CONCLUSION

This study indicate that EPE could be recommended as a colon anticancer through increase the goblet cells, induce apoptosis through increase TNF-α, and decrease TGF-β.

Effect in white shrimp Litopenaeus vannamei of Eleutherine bulbosa (Mill.) Urb. Powder on immune genes expression and resistance against Vibrio parahaemolyticus infection

This study investigated the influence of Eleutherine bulbosa (Mill.) Urb. on the immune responses, bacterial population in the intestines, and resistance of white shrimp, Litopenaeus vannamei, against infection with Vibrio parahaemolyticus. Shrimp were fed with three dosages of powder, at 6.25 g kg-1 (P6.25), 12.5 g kg-1 (P12.5), and 25 g kg-1 (P25). One dosage of the crude extract was provided, 1.25 g kg-1 (E1.25), and the controls without administration of E. bulbosa consisted of a positive control (PC) and a negative control (NC). Feed supplementation was carried out for 30 days; then shrimp from all treatments were challenged by intramuscular injection with V. parahaemolyticus (10⁶ cfu/mL), except for the NC. The results showed that supplementation with the powder and extract of E. bulbosa for 30 days resulted in significantly higher (P < 0.05) immune responses (total hemocyte count (THC), phenoloxidase activity (PO), respiratory bursts (RBs)), gene expression (prophenoloxidase (proPO), lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP)), and total bacterial count (TBC) compared to PC/NC. In post challenge testing, there were significantly higher levels for THC, PO, RBs, proPO, LGBP, and PE (peroxinetin), and the treatments were able to suppress V. parahaemolyticus in the intestines, hepatopancreas, and muscles and to reduce damage to the muscles and hepatopancreas. The survival rate with P12.5 was significantly higher compared to the other treatments. It was concluded that the shrimp receiving supplementation with the powder and extract of E. bulbosa had increased immunity and resistance against V. parahaemolyticus infection, with the best dosage being the P12.5 treatment.

Biosynthesis of the anti-diabetic metabolite montbretin A: glucosylation of the central intermediate mini-MbA

Type 2 diabetes (T2D) affects over 320 million people worldwide. Healthy lifestyles, improved drugs and effective nutraceuticals are different components of a response against the growing T2D epidemic. The specialized metabolite montbretin A (MbA) is being developed for treatment of T2D and obesity due to its unique pharmacological activity as a highly effective and selective inhibitor of the human pancreatic α-amylase. MbA is an acylated flavonol glycoside found in small amounts in montbretia (Crocosmia × crocosmiiflora) corms. MbA cannot be obtained in sufficient quantities for drug development from its natural source or by chemical synthesis. To overcome these limitations through metabolic engineering, we are investigating the genes and enzymes of MbA biosynthesis. We previously reported the first three steps of MbA biosynthesis from myricetin to myricetin 3-O-(6'-O-caffeoyl)-glucosyl rhamnoside (mini-MbA). Here, we describe the sequence of reactions from mini-MbA to MbA, and the discovery and characterization of the gene and enzyme responsible for the glucosylation of mini-MbA. The UDP-dependent glucosyltransferase CcUGT3 (UGT703E1) catalyzes the 1,2-glucosylation of mini-MbA to produce myricetin 3-O-(glucosyl-6'-O-caffeoyl)-glucosyl rhamnoside. Co-expression of CcUGT3 with genes for myricetin and mini-MbA biosynthesis in Nicotiana benthamiana validated its biological function and expanded the set of genes available for metabolic engineering of MbA.

Iridal-Type Triterpenoids with a Cyclopentane Unit from the Rhizomes of Belamcanda chinensis

Ten new iridal-type triterpenoid derivatives, polycycloiridals K-T (1-10), with a cyclopentane moiety originating from the cyclization of the homofarnesyl side chain were isolated from the rhizomes of Belamcanda chinensis. Their structures were established by spectroscopic data, a single-crystal X-ray diffraction analysis, TDDFT quantum mechanical calculations, and chemical derivatization. Compounds 2 and 10 exhibited 33.4% and 32.9% inhibitory activities, respectively, against PTP1b (protein tyrosine phosphatase) at a concentration of 10 μM. A putative biosynthetic pathway is proposed.

Evaluation of in vitro neutralization of epoxyscillirosidine by antibodies raised in sheep

Intoxication by Moraea pallida Bak. (yellow tulp) in livestock is of great importance in South Africa, ranking top among all plant-induced cardiac glycoside toxicosis. The toxic principle, a bufadienolide, is 1α, 2α-epoxyscillirosidine. Treatment of poisoning is challenging and affected livestock often succumbs due to the stress of handling. Manipulating animals to resist poisoning is a potential management strategy. The goal of this study was to explore the potential to develop a vaccine against epoxyscillirosidine by raising antibodies against epoxyscillirosidine in sheep and to assess the neutralization ability of the antibodies in vitro. Epoxyscillirosidine was successfully conjugated to keyhole limpet haemocyanin (KLH) and bovine serum albumin (BSA) rendering them immunogenic. The sheep, vaccinated with epoxyscillirosidine-KLH conjugate (n = 4) and KLH (n = 2) with Montanide, developed antibodies as determined with an indirect enzyme linked immunosorbent assay (ELISA). Total immunoglobulins from sera of vaccinated and control sheep that were purified and concentrated using ammonium sulphate precipitation were 11,940 and 7850 μg, respectively. The in vitro neutralization assay using the methyl blue tetrazolium bromide (MTT) cell viability assay indicated no significant difference (p > 0.05) between anti-epoxyscillirosidine-KLH and KLH antibodies. Rather, the antibodies seemed to enhance the cytotoxicity of epoxyscillirosidine in H9c2 cells. Thus, it is necessary to develop improved vaccination methods to generate antibodies capable of neutralizing the functional group responsible for epoxyscillirosidine toxicity.

[A new naphthalene derivative from bulbs of Eleutherine americana]

A new naphthalene derivative and three known compounds were isolated from the petroleum ether extract of the bulbs of Eleutherine americana by using various chromatographic techniques, such as column chromatography over silica gel and semi-preparative HPLC. Their structures were elucidated by spectroscopic date (MS, UV, IR, NMR), which were identified as eleutherol B (1), 4,8-dihydroxy-3-methoxy-1-methylanthraquinone-2-carboxylic acid methyl ester (2), 8-hydroxy-3,4-dimethoxy-1-methylanthraquinone-2-carboxylic acid methyl ester (3), and isoeleutherine (4). Compound 1 is a new compound. The diastolic blood vessels activity of compound 1 and 2 were potent, reaching 82.5% and 85.3% at the concentration of 10 μmol·L⁻¹, which were basically the same as that of the positive drug tanshinone ⅡA.

Probing the Antiallergic and Anti-inflammatory Activity of Biflavonoids and Dihydroflavonols from Dietes bicolor

Dietes bicolor (Iridaceae) is an ornamental plant used by African local healers to treat diarrhea and dysentery. A new dihydroflavonol, (2R,3R)-3,5,7-trihydroxy-8-methoxyflavanone (1); two known dihydroflavonols, trans-3-hydroxy-5-methoxy-6,7-methylenedioxyflavanone (2) and trans-3-hydroxy-5,7-dimethoxyflavanone (3); the known isoflavone orobol 7,3'-di-O-methyl ether (4); the known biflavones lanaroflavone (5), robustaflavone (6), and amentoflavone (7); and β-sitosterol (8) were isolated from the CH₂Cl₂ fraction of D. bicolor leaves. The extract showed potent activity in antiallergic and anti-inflammatory assays. The structures of the isolates were identified by spectroscopic and spectrometric methods. Compounds 6 and 7 (400 μM) exhibited antiallergic activity by inhibiting antigen-induced β-hexosaminidase release at 45.7% and 46.3%, respectively. Moreover, 6 and 7 exerted anti-inflammatory activity as demonstrated by the inhibition of superoxide anion generation with an IC₅₀ value of 1.0 μM as well as the inhibition of elastase release with IC₅₀ values of 0.45 and 0.75 μM, respectively. The anti-inflammatory activity was further explained by the virtual docking of the isolated compounds to the binding sites in the human neutrophil elastase (HNE) crystal structure using Discovery Studio 2.5. It was concluded that the biflavonoids bind directly to HNE and inhibit its enzymatic activity based on the CDOCKER algorithm. The data provided evidence for the potential use of D. bicolor against certain diseases related to allergy and inflammation.

Belamcanda chinensis (L.) DC-An ethnopharmacological, phytochemical and pharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE

Belamcanda chinensis (L.) DC is the sole species in the genus Belamcanda Adans. (Iridaceae), found mainly in Northeast Asia. Bombus chinensis has long been used in traditional Chinese medicine for its multiple therapeutic uses in the form of antipyretic agents, antidote, expectorant, antiphlogistic and analgesic.

AIM OF THE REVIEW

This manuscript comprehensively summarizes the various studies published in recent years on the botany, ethnopharmacology, phytochemistry, biological activity and toxicology of B. chinensis. We hope to provide a foundation for future studies on the mechanism of action and development of better therapeutic agents based on B. chinensis.

MATERIAL AND METHODS

All information available on B. chinensis was collected using electronic search engines, such as PubMed, SciFinder Scholar, CNKI, TPL (www.theplantlist.org), Google Scholar and Web of Science.

RESULTS

The analysis shown that ethno-medical uses of B. chinensis have been recorded in China, Japan and Korea since a long time. Based on a phytochemical investigation, this plant contains flavonoids, terpenoids, quinones, phenolic compounds, ketones, organic acids, etc. Crude extracts and pure compounds isolated from B. chinensis exhibited various biological effects.

CONCLUSIONS

In light of its long traditional use and the modern phytochemical and pharmacological studies summarized here, B. chinensis is known to be a promising medicinal plant with the isolated extracts and chemical components showing a wide range of biological activities. Thus, it is imperative that the necessary programs and value assessment of B. chinensis be established for further studies. It is also important that the synergistic or antagonistic effects of this traditional herbal medicine are investigated in depth to identify more bioactive components by bioactivity-guided isolation strategies, and to illustrate the mechanisms of action targeting on ethnomedical uses. Future clinical studies can also focus on the main therapeutic aspects, toxicity and adverse effects of B. chinensis.

Antiproliferative effect of extracts and pyranonaphthoquinones obtained from Cipura paludosa bulbs

CONTEXT

Cipura paludosa Aubl. (Iridaceae) is widely used in folk medicine to treat several ailments. Experimental studies have confirmed its anti-inflammatory, antinociceptive, and neuroprotective effects.

OBJECTIVE

This study evaluates the possible antiproliferative potential of the crude methanol extract and three isolated compounds from the bulbs of C. paludosa.

MATERIALS AND METHODS

Phytochemical analysis was carried out by conventional chromatographic techniques, and the resulting compounds were identified by NMR (1)H and (13)C. The antiproliferative activity was analysed using the sulforhodamine B assay.

RESULTS

Crude methanol extract of C. paludosa bulbs showed GI50 values of between 1.6 and 30.8 μg/mL. The naphthoquinone derivatives (eleutherine, isoeleutherine, and eleutherol) isolated from the bulbs of C. paludosa exhibited promising cytotoxicity against several human tumour cell lines, especially the two main compounds, eleutherine and isoeleutherine, against glioma and breast cancer cell lines, with TGI values of between 2.6 and 13.8 μg/mL.

CONCLUSION

Cipura paludosa bulbs produce active principles with relevant antiproliferative potential, such as naphthoquinone derivatives, identified as eleutherine, isoeleutherine, and eleutherol. This is the first report indicating C. paludosa with antiproliferative potential.

Antifungal Activity of Pyranonaphthoquinones Obtained from Cipura paludosa Bulbs

Previous studies with the bulbs of Cipura paludosa (Iridaceae) showed the presence of pyranonaphthoquinones, including eleutherine, isoeleutherine and eleutherol. The aim of this study was to evaluate the antifungal properties of these compounds. The activity was tested against the clinically relevant yeasts Candida albicans, C. tropicalis, Saccharomyces cerevisiae and Cryptococcus neoformans with the microbroth dilution method, following the guidelines of CLSI. Eleutherine, isoeleutherine and eleutherol all presented significant antifungal activity, especially the first two, the major components, with MIC values between 7.8 and 250 µg/mL. In conclusion, these results demonstrate that C. paludosa bulbs produce active principles with relevant antifungal potential, contributing, at least in part, to the antimicrobial effect evidenced for this plant and justifying its popular use against infections.

Antibacterial and antibiotic resistance modifying activity of the extracts from Allanblackia gabonensis, Combretum molle and Gladiolus quartinianus against Gram-negative bacteria including multi-drug resistant phenotypes

BACKGROUND

Bacterial resistance to antibiotics is becoming a serious problem worldwide. The discovery of new and effective antimicrobials and/or resistance modulators is necessary to tackle the spread of resistance or to reverse the multi-drug resistance. We investigated the antibacterial and antibiotic-resistance modifying activities of the methanol extracts from Allanblackia gabonensis, Gladiolus quartinianus and Combretum molle against 29 Gram-negative bacteria including multi-drug resistant (MDR) phenotypes.

METHODS

The broth microdilution method was used to determine the minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) of the samples meanwhile the standard phytochemical methods were used for the preliminary phytochemical screening of the plant extracts.

RESULTS

Phytochemical analysis showed the presence of alkaloids, flavonoids, phenols and tannins in all studied extracts. Other chemical classes of secondary metabolites were selectively presents. Extracts from A. gabonensis and C. molle displayed a broad spectrum of activity with MICs varying from 16 to 1024 μg/mL against about 72.41% of the tested bacteria. The extract from the fruits of A. gabonensis had the best activity, with MIC values below 100 μg/mL on 37.9% of tested bacteria. Percentages of antibiotic-modulating effects ranging from 67 to 100% were observed against tested MDR bacteria when combining the leaves extract from C. molle (at MIC/2 and MIC/4) with chloramphenicol, kanamycin, streptomycin and tetracycline.

CONCLUSION

The overall results of the present study provide information for the possible use of the studied plant, especially Allanblackia gabonensis and Combretum molle in the control of Gram-negative bacterial infections including MDR species as antibacterials as well as resistance modulators.

Applications of microencapsulated Bifidobacterium longum with Eleutherine americana in fresh milk tofu and pineapple juice

Bifidobacterium longum was microencapsulated by extrusion technique and added in fresh milk tofu and pineapple juice. Microencapsulation of B. longum with Eleutherine americana extract, oligosaccharides extract, and commercial fructo-oligosaccharides was assessed for the bacterial survival after sequential exposure to simulated gastric and intestinal juices, and refrigeration storage. Microencapsulated B. longum with the extract and oligosaccharides extract in the food products showed better survival than free cells under adverse conditions. Sensory analysis demonstrated that the products containing co-encapsulated bacterial cells were more acceptable by consumers than free cells. Pineapple juice prepared with co-encapsulated cells had lower values for over acidification, compared with the juice with free cells added. This work suggested that microencapsulated B. longum with E. americana could enhance functional properties of fresh milk tofu and pineapple juice.

Molecular and Biochemical Analysis of Chalcone Synthase from Freesia hybrid in flavonoid biosynthetic pathway

Chalcone synthase (CHS) catalyzes the first committed step in the flavonoid biosynthetic pathway. In this study, the cDNA (FhCHS1) encoding CHS from Freesia hybrida was successfully isolated and analyzed. Multiple sequence alignments showed that both the conserved CHS active site residues and CHS signature sequence were found in the deduced amino acid sequence of FhCHS1. Meanwhile, crystallographic analysis revealed that protein structure of FhCHS1 is highly similar to that of alfalfa CHS2, and the biochemical analysis results indicated that it has an enzymatic role in naringenin biosynthesis. Moreover, quantitative real-time PCR was performed to detect the transcript levels of FhCHS1 in flowers and different tissues, and patterns of FhCHS1 expression in flowers showed significant correlation to the accumulation patterns of anthocyanin during flower development. To further characterize the functionality of FhCHS1, its ectopic expression in Arabidopsis thaliana tt4 mutants and Petunia hybrida was performed. The results showed that overexpression of FhCHS1 in tt4 mutants fully restored the pigmentation phenotype of the seed coats, cotyledons and hypocotyls, while transgenic petunia expressing FhCHS1 showed flower color alteration from white to pink. In summary, these results suggest that FhCHS1 plays an essential role in the biosynthesis of flavonoid in Freesia hybrida and may be used to modify the components of flavonoids in other plants.

[Study on relieving effects of exogenous SNP, Spd on Belamcanda chinensis under salt-alkalline stress]

The study is aimed to provide the theoretical basis for exploiting and utilization of salt-alkaline soil and cultivating Belamcanda chinensis. In this study, we exerted exogenous substances SNP, Spd to relieve the damage of the mixing salt-alkaline stress on B. chinensis seedling which is NaCl, Na2SO4, NaHCO3 and Na2CO3 four kinds of salt molar ratio of 9: 1: 9: 1, salt concentration of 100 mmol x L(-1). The result illustrated that high pH stress is a major factor caused the salt-alkaline stress, the interaction between time and the concentration of each, treatment was observed, what is more, there are synergies between the salt and alkali stress. The content of B. chinensis seedling leaves' membrane peroxidation index (MDA, O2-*) and metabolites (soluble protein, soluble sugars, organic acids) are showing an upward trend in varying degrees under 100 mmol x L(-1) salt-alkaline stress. It is effective to reduce the content of MDA and O2-*. and improve the levels of metabolites, in which the SNP (0.05 mmol x L(-1)) and Spd (0.5 mmol x L(-1)) to alleviate damage effects is the best. Therefore we can hold the conclusion that SNP and Spd can effectively mitigate the damage of B. chinensis seedling on salt-alkaline stress, improve the resistance ability of B. chinensis seedling which can provide the scientific basis for the utilization of salt-alkaline soil, and the cultivation of B. chinensis.

Iridal-type triterpenoids with neuroprotective activities from Iris tectorum

Six novel iridal-type triterpenoids with a previously unreported 3,6-dihydro-2H-pyran moiety, named spirioiridotectals A-F (1-6), were isolated from the ethanol extract of the rhizomes of Iris tectorum. Their structures were elucidated on the basis of extensive spectroscopic analysis. Furthermore, in in vitro bioactivity assays, compounds 1, 2, and 6 exhibited neuroprotective activities against serum-deprivation-induced PC12 cell damage.

Spatial variation of epoxyscillirosidine concentrations in Moraea pallida (yellow tulp) in South Africa

Moraea pallida (yellow tulp) poisoning is economically the most important intoxication of livestock in South Africa. Poisoning varies according to locality, climatic conditions and growth stage of the plant. The primary objective of this study was to determine the concentration of the toxic principle, epoxyscillirosidine, in yellow tulp leaves and to ascertain the variability of epoxyscillirosidine concentrations within and between different locations. A secondary objective was to utilise Geographic Information Systems in an attempt to explain the variability in toxicity. Flowering yellow tulp plants were collected at 26 sampling points across 20 districts of South Africa. The leaves of five plants per sampling point were extracted and submitted for liquid chromatography/mass spectrometry analysis. A large variation in mean epoxyscillirosidine concentrations, ranging from 3.32 μg/g - 238.27 μg/g, occurred between different geographical regions. The epoxyscillirosidine concentrations also varied tremendously between individual plants (n = 5) collected at the same sampling point, with up to a 24 times difference between the lowest and highest concentration detected. No generalised correlation between epoxyscillirosidine concentrations and soil elemental concentrations could be established. However, samples obtained from the north-eastern part of the sampling region tended to have higher epoxyscillirosidine concentrations compared to samples obtained from the south-western part of the sampling region. Higher toxin concentrations in the north-east were associated with statistically significant higher soil concentrations of iron, bismuth, bromide, cadmium, chromium, rubidium, tellurium, thallium, titanium and zinc, whilst soil concentrations of strontium and soil pH, were significantly lower. This study corroborated the contention that epoxyscillirosidine concentration in yellow tulp fluctuates and may explain the variability in toxicity.

Flower color polymorphism in Iris lutescens (Iridaceae): biochemical analyses in light of plant-insect interactions

We describe a flower color polymorphism in Iris lutescens, a species widespread in the Northern part of the Mediterranean basin. We studied the biochemical basis of the difference between purple and yellow flowers, and explored the ecological and evolutionary consequences of such difference, in particular visual discrimination by insects, a potential link with scent emitted and the association between color and scent. Anthocyanins were found to be present in much greater concentrations in purple flowers than in yellow ones, but the anthocyanin composition did not differ between color morphs. Likewise, no quantitative difference in anthocyanin content was found between vegetative tissues of the two morphs. Floral anthocyanins were dominated by delphinidin 3-O-(p-coumaroylrutinoside)-5-O-glucoside (also called delphanin) and its aliphatic derivatives. Small amounts of delphinidin 3-O-(p-caffeoylrutinoside)-5-O-glucoside and its aliphatic derivatives were also characterized. Based on a description of bumblebees' (one of the main pollinators of I. lutescens) color perception, purple and yellow flowers of I. lutescens could be visually discriminated as blue and blue-green, respectively, and likely by a wide variety of other insects. The overall chemical composition of the scent produced was not significantly different between morphs, being dominated by terpenoids, mainly myrcene, (E)-β-ocimene and limonene. A slight color-scent correlation was nevertheless detected, consistent with the shared biosynthetic origin of both pigments and volatile compounds. Therefore in this species, the difference in the amounts of pigments responsible for flower color difference seems to be the major difference between the two morphs. Pollinators are probably the main selective agent driving the evolution of flower color polymorphism in I. lutescens, which represents a suitable species for investigating how such polymorphism is maintained.

Oil-producing flowers within the Iridoideae (Iridaceae): evolutionary trends in the flowers of the New World genera

BACKGROUND AND AIMS

Oil-producing flowers related to oil-bee pollination are a major innovation in Neotropical and Mexican Iridaceae. In this study, phylogenetic relationships were investigated among a wide array of New World genera of the tribes Sisyrinchieae, Trimezieae and Tigridieae (Iridaceae: Iridoideae) and the evolution of floral glandular structures, which are predominantly trichomal elaiophores, was examined in relation to the diversification of New World Iridaceae.

METHODS

Phylogenetic analyses based on seven molecular markers obtained from 97 species were conducted to produce the first extensive phylogeny of the New World tribes of subfamily Iridoideae. The resulting phylogenetic hypothesis was used to trace the evolutionary history of glandular structures present in the flowers of numerous species in each tribe. Hypotheses of differential diversification rates among lineages were also investigated using both topological and Binary-State Speciation and Extinction methods.

KEY RESULTS AND CONCLUSIONS

Floral glandular structures and especially trichomal elaiophores evolved multiple times independently in the American tribes of Iridoideae. The distribution pattern of species displaying glandular trichomes across the phylogeny reveals lability in the pollination system and suggests that these structures may have played a significant role in the diversification of the Iridoideae on the American continent.

Preparative isolation and purification of seven isoflavones from Belamcanda chinensis

INTRODUCTION

Isoflavonoids from Belamcanda chinensis are known to have a number of physiological benefits including anti-inflammatory, anti-angiogenic and anti-mutagenic properties. However, there have been no reports on the effective isolation and purification of isoflavonoids from B. chinensis.

OBJECTIVE

To develop an efficient method for the preparative isolation and purification of isoflavones from B. chinensis by high-speed counter-current chromatography (HSCCC).

METHODOLOGY

A two-step HSCCC isolation method was developed using solvent system of n-hexane-ethyl acetate-2-propanol-methanol-water (5:6:2:3.5:6, v/v) and of ethyl acetate-methanol-water (10:2:9, v/v). FLASH purification system (45% methanol, isocratic) was also used for further purification. The purities and chemical structures of the isolated compounds were determined by high-performance liquid chromatography-photodiode array detection (HPLC-PDA), electrospray ionisation-mass spectrometry (ESI-MS), ¹H- and ¹³C-nuclear magnetic resonance spectrometry (NMR) and nuclear overhauser enhancement (NOE).

RESULTS

HSCCC was successfully used for the preparative separation and purification of seven isoflavones, including tectoridin (145.4 mg, 97.5%), iridin (77.9 mg, 94.0%), irilin D (42.0 mg, 92.0%), tectorigenin (294.1 mg, 98.6%), iristectorigenin A (86.8 mg, 93.4%), irigenin (141.8 mg, 95.8%) and irisflorentin (73.4 mg, 94.7%) from the rhizomes of B. chinensis.

CONCLUSION

Two isoflavone glycosides and five isoflavone derivatives were successfully isolated and purified from the crude methanol extract of dried rhizomes of the B. chinensis by HSCCC.

A new naphthoquinone isolated from the bulbs of Cipura paludosa and pharmacological activity of two main constituents

Cipura paludosa (Iridaceae) is a plant that is distributed in the north region of Brazil. Its bulbs are used in folk medicine to treat inflammation and pain. Four naphthalene derivatives have been isolated from the bulbs of this plant. Three of them have been identified as the known naphthalene derivatives, eleutherine, iso-eleutherine, and hongkonin. The structure of the fourth and new component was determined as 11-hydroxyeleutherine by extensive NMR study. In addition, the IN VIVO effect of the two major compounds, eleutherine and iso-eleutherine, was evaluated in carrageenan-induced hypernociception and inflammation in mice. Eleutherine and iso-eleutherine (1.04-34.92 µmol/kg), dosed intraperitoneally (i.p.) or orally (p.o.), decreased the carrageenan-induced paw oedema (i.p. - inhibitions of 36 ± 7 % and 58 ± 14 %, respectively; p.o. - inhibitions of 36 ± 7 % and 58 ± 14 %, respectively). Iso-eleutherine, but not eleutherine, significantly reduced (inhibitions of 39 ± 4 %) the plasma extravasation induced by intradermal (i.d.) injection of carrageenan. Likewise, eleutherine and iso-eleutherine (1.04-34.92 µmol/kg, i.p. or p.o.) were also effective in preventing the carrageenan-induced hypernociceptive response (i.p. - inhibition of 59 ± 4 % and 63 ± 1 %, respectively; p.o. - inhibitions of 36 ± 7 % and 58 ± 14 %, respectively). It was also suggested that the anti-inflammatory and anti-hypernociceptive effects of eleutherine or iso-eleutherine partly depend on the interference with the synthesis or activity of mast cell products, kinins, cytokine, chemokines, prostanoids, or sympathetic amines. Our findings show that two major compounds of C. paludosa contain pharmacologically active constituents that possess antinociceptive and anti-inflammatory activity, justifying, at least in part, its popular therapeutic use for treating conditions associated with pain.

[Study on seed quality detection and quality standard of Belamcanda chinensis]

OBJECTIVE

To propose the seed quality standard of Belamcanda chinensis.

METHOD

The seed purity, 1000-grain weight, water content, vitality, germination rate of seed of B. chinensis from different producing areas were measured, and seed characteristics were observed. Cluster analysis was used to analyze to data.

RESULT

The first level seed was lustrously dark and thoroughly rounded, seed purity was above 98%, 1000-grain weight was above 28.00 g, water content was lower than 12.8%, vitality was over 90%, germination rate was over 85%. The second level seed was dark and relatively rounded, seed purity was above 92%, 1000-grainweight was above 20.00 g, water content was below 12.8%, vitality was between 70%-90%, germination rate was between 65%-85%, the third level seed was puce, seed purity was above 86%, 1000-grain weight was above 20.00 g, water content was below 12.80%, vitality was over 50%, germination rate was above 40%.

CONCLUSION

The seed purity of B. chinensis was almost above 90%, and 1000-grain weight was between 15.27 and 30.76 g. The vitality and the germination rate of B. chinensis seeds from different sources varied obviously.

Cipura paludosa attenuates long-term behavioral deficits in rats exposed to methylmercury during early development

In the present study, we evaluated the effects of the ethanolic extract (EE) of Cipura paludosa on locomotor, and anxiety- and depression-like behaviors of adult rats exposed to MeHg during early development. Additionally, the antioxidant enzymes catalase (CAT) and selenium-glutathione peroxidase (Se-GPx) were measured in cortical, hippocampal, and cerebellar tissues. Pregnant Wistar rats were treated by gavage with a single dose of MeHg (8 mg/kg) on gestational day 15, the developmental stage critical for cortical neuron proliferation. Moreover, prenatal MeHg exposure inhibited CAT and Se-GPx in the cortex and cerebellum. Chronic treatment with the EE of C. paludosa attenuated these emotional and antioxidant deficits induced by prenatal MeHg toxic exposure. This study provides novel evidence that developmental exposure to MeHg can affect not only cognitive functions but also locomotor, and anxiety- and depression-like behaviors.

Screening of plants of Amaryllidaceae and related families from Panama as sources of acetylcholinesterase inhibitors

CONTEXT

This is the first comprehensive study of the acetylcholinesterase (AChE) inhibitory activity of species of the family Amaryllidaceae and 13 related families from Panama.

OBJECTIVE

Exploration of the potential sources of AChE inhibitors with radical scavenging activity from Amaryllidaceae and 13 related families from Panama.

MATERIALS AND METHODS

The studied plants were screened with anti-acetylcholinesterase bioautographic and DPPH free radical scavenging assays.

RESULTS

From the 57 plants studied, eight (14%) showed strong inhibition of AChE, and 29 (51%) plants showed moderate inhibition of AChE.

DISCUSSION AND CONCLUSION

Sagittaria lancifolia L. (Alismataceae), Crinum jagus (Thomps.) (Amaryllidaceae), Crinum x amabile Donn (Amaryllidaceae), Crinum zeylanicum (L.) L. (Amaryllidaceae), Crocosmia x crocosmiiflora (Lemoine ex Anonymous) N.E. Br. (Iridaceae), Sisyrinchium tinctorium Kunth (Iridaceae), Agapanthus praecox subsp. orientalis (F.M. Leight.) F.M. Leight. (Liliaceae), and Xyris jupicai Rich. (Xyridaceae) were the most active plants, inhibiting AChE at 100 microg on the TLC bioautographic method for the detection of acetylcholinesterase inhibitors. Out of the eight most active plants, two plants, Crinum zeylanicum (L.) L. and Xyris jupicai Rich., showed antioxidant activity.

[Studies on the chemical constituents from the aerial parts of Gladiolus gandavensis]

OBJECTIVE

To study the chemical constituents of the aerial parts of Gladiolus gandavensis.

METHODS

These compounds were isolated by silica gel, Sephades LH-20 and RP-18 column chromatographies. And their structures were elucidated by spectroscopic methods.

RESULTS

Ten compounds were isolated, and their structures were identified as kaempferol (I), apigenin-7-O-alpha-L-rhamnoside(II), tamarixetin-3-robinobioside(III), nicotiflorin(IV), astragalin-2"-O-beta-D-glucopyranoside(V), quercetin-3-O-(6"-O-Ecaffeoyl)-beta-D-glucopyranoside(VI), beta-sitosterol(VII), daucosterol(VII), isopentylgentiobioside(IX), glycerol-alpha-monohexacosanate(X).

CONCLUSION

Except for compounds VII and VIII, others compounds are obtained from this plant for the first time.

Naphthoquinones, anthraquinones and naphthalene derivatives from the bulbs of Eleutherine americana

A new naphthoquinone, named eleuthinone A ( 8), two new anthraquinones, named eleuthraquinone A and B ( 12, 13), a naphthalene derivative, named eleucanarol ( 14) were isolated from the bulbs of ELEUTHERINE AMERICANA, together with two new natural products previously synthesized, and nine known compounds. Their structures were established based on spectroscopic evidence. Their antibacterial activities against STAPHYLOCOCCUS AUREUS ATCC25923 and ATCC27664, an enterotoxin producing strain were investigated.

[Studies on chemical constituents of Eleutherine americana]

OBJECTIVE

To research the chemical constituents from Eleutherine americana.

METHODS

Column chromatography with silica gel was employed to isolate and purify the constituents. Their structures were elucidated by means of MS and NMR.

RESULTS

Eight constituents were obtained and identified as Isoeleutherol (1), eleutherin (2), isoeleutherin (3), beta-sitosterol(4), 8-hydroxy-3, 4-Dimethoxy-1-methyl-anthra-9, l0-quinone-2-carboxylic acid methyl ester (5), Hongconin (6), 4,8-Dihydroxy-3-Methoxy-1-methyl-anthra-9,10-quinone-2-carboxylic acid methyl ester (7), Eleutherinone (8), Kadsuric acid (9).

CONCLUSION

Compound 9 is isolated from the plant for the first time.

[Analysis and characterization of Belamcanda chinensis with space mutagenesis breeding by X-ray fluorescence analysis and X-ray diffraction]

The contents of various elements in the fourth generation Belamcanda chinensis (L.) DC. with space mutagenesis breeding were analyzed and characterized. X-ray fluorescence spectrum analysis (XRF) and powder X-ray diffraction (PXRD) were applied jointly. It was found that the content of K element in the space flight mutagenesis increases 1.03 and 0.31 times, Mg enhances 1.44 and 0.06 times, but Al reduces 38.5% and 85.5% respectively compared to the contents in the ground group and the comparison group, while those of Ca, Mn and Fe enhance 0.95, 0.30 and 0.29 times respectively contrasted to the ground group. Besides, there was discovered the crystal of whewellite in the Belamcanda chinensis (L.) DC. and the content in the ground group is less than that of the outer space and the outer space group, which in turn is less than that of the comparison group. It is concluded that the contents of mineral elements indispensable to body in the space group are closer or superior to the comparison, group as compared to the ground group. In the present paper, a quick and simple appraising method is offered, which may be of great significance to the popularization of the planting outer space Chinese traditional medicine to filtrate more excellent breed and set up norm of quality appraisal.

Chemical constituents from Belamcanda chinensis

One new flavone and one new isoflavone glycoside were isolated along with 15 known compounds from the rhizome of Belamcanda chinensis (Iridaceae), and their structures were characterised as 5,4'-dihydroxy-6,7-methylenedioxy-3'-methoxyflavone (1) and 3',5'-dimethoxy irisolone-4'-O-beta-D-glucoside (2) on the basis of spectroscopic methods.

Phytoestrogens from Belamcanda chinensis regulate the expression of steroid receptors and related cofactors in LNCaP prostate cancer cells

OBJECTIVE

To investigate the changes in expression underlying the marked reduction of tumour growth in vivo, by analysing the effect of Belamcanda chinensis extract (BCE) on LNCaP cells in vitro, as phytoestrogens are chemopreventive in prostate cancer, and in previous studies we examined the effects of the isoflavone tectorigenin isolated from B. chinensis on LNCaP prostate cancer cells, and a BCE consisting of 13 phytoestrogenic compounds on tumour-bearing nude mice.

MATERIALS AND METHODS

LNCaP cells were treated with 100, 400 or 1400 microg/mL BCE; proliferation was assessed with an Alamar Blue assay. We used real-time reverse transcription-polymerase chain reaction to quantify mRNA expression of the androgen receptor (AR), the AR coactivator prostate derived Ets transcription factor (PDEF), NKX3.1, prostate specific antigen (PSA) and oestrogen receptor-beta (ER-beta) compared with the expression of the housekeeping gene porphobilinogen deaminase (PBGD). PSA secretion from LNCaP cells was measured and protein expression of the AR investigated by Western blot analysis.

RESULTS

Concomitant with a marked decrease of tumour cell proliferation BCE down-regulated the expression of the AR, PDEF, NKX3.1 and PSA. In the same experiments, the expression of PBGD was unaltered, whereas ER-beta expression increased. Furthermore, AR protein and PSA secretion were markedly diminished after treatments with the BCE.

CONCLUSION

BCE, comprising 13 different phytoestrogens, decreases the expression of the AR and its co-activator PDEF concomitant with diminished cell proliferation and PSA secretion. NKX3.1 expression was also reduced by BCE. We hypothesise that the positive effects of BCE are initiated by up-regulation of the ER-beta, a putative tumour-suppressor gene.

[Studies on dynamic variation of six isoflavones contents in rhizomes of Belamcanda chinensis]

OBJECTIVE

To study the monthly dynamic variation of the contents of six isoflavones in the rhizomes of Belamcanda chinensis cultivated in Nanjing, and decide optimum harvesting times.

METHOD

HPLC method was used to determine the contents of six isoflavones in the samples collected at different times.

RESULT

It was shown that the total contents of six isoflavones in the rhizomes of B. chinensis collected in April were the highest.

CONCLUSION

The most optimum collecting time of rhizomes of B. chinensis cultivated in Nanjing should be in April.

Antimutagenic and antioxidant activity of the extract from Belamcanda chinensis (L.) DC

The antioxidant and antimutagenic properties of the extract from the oriental natural drug - Belamcanda chinensis (L.)DC. (Iridaceae) rhizomes have been examined. Three different antioxidant assays and Salmonella antimutagenic test have been used. The extract has strong free radical scavenging activity as shown by the DPPH assay with EC50 of 63.4 microg/mL. Similarly, the high ability to reduce the transition metal ions was shown by phosphomolybdenum assay as well as effective prevention of hydroxyl radical induced linoleic acid peroxidation. The latter averaged 77.9% with an EC50 of 45 microg/mL. The mutations induced in two Salmonella typhimurium strains (TA98 and TA100) by both directly (NQNO) and indirectly acting (2AF) chemical mutagens were inhibited efficiently in dose dependent manner for concentrations of 50-500 microg/mL. The inhibition percentage in TA98 was 62.8% for direct mutagen and 94.4% for enzymatically activated promutagen. In TA100 the inhibition was 82.7% and 73.5%, respectively.

Inhibitory effects of Irigenin from the rhizomes of Belamcanda chinensis on nitric oxide and prostaglandin E(2) production in murine macrophage RAW 264.7 cells

In the present study, we investigated antiinflammatory effects of six flavonoids isolated from the rhizomes of Belamcanda chinensis (Iridaceae) in RAW 264.7 macrophages. The results indicated that irigenin concentration dependently inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin (PG) E(2) production. Furthermore, this compound inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 proteins and mRNAs without an appreciable cytotoxic effect. Treatment of the transfectant RAW 264.7 cells with irigenin reduced the level of nuclear factor-kappaB (NF-kappaB) activity, also effectively lowered NF-kappaB binding measured by electrophoretic mobility shift assay (EMSA), which was associated with decreased p65 protein levels in the nucleus. On the basis of the above data, we suggest that the effect of irigenin in decreasing LPS-induced NO and PGE(2) synthesis is due to diminish the mRNA and protein expression of iNOS and COX-2, respectively, also may be due to under the suppression of NF-kappaB activation. Therefore, irigenin isolated from the rhizomes of Belamcanda chinensis could be offered as a leading compound for anti-inflammation.

Anthraquinones from Gladiolus gandavensis

Five new anthraquinones have been obtained from the ethanolic extracts of the subterranean corms of Gladiolus gandavensis Van Houtt. Their structures were elucidated as 3,8-dihydroxy-6-methoxy-1-methyl-anthraquinone (gandavensin D, 1), methyl 3,8-dihydroxy-6,7-methylenedioxy-1-methyl-anthraquinone- 2-carboxylate (gandavensin E, 2), 2,3,8-trihydroxy-6-methoxy-1-methoxymethyl-anthraquinone (gandavensin F, 3), 8-hydroxy-3,6-dimethoxy-1-methyl-anthraquinone-2-carboxylic acid (gandavensin G, 4) and 1,7-dihydroxy-3,6-dimethoxy-anthraquinone (gandavensin H, 5) on the basis of spectral data. The known compounds isolated for the first time from this plant have been determined to be methyl 3,6,8-trihydroxy-7-methoxy-1-methyl-anthraquinone-2-carboxylate (6), methyl 3,6,8-trihydroxy-1-methyl-anthraquinone-2-carboxylate (7), 3,8-dihydroxy-6-methoxy-1-methyl-anthraquinone-2-carboxylic acid (8), 3,6,8-trihydroxy-1-methyl-anthraquinone-2-carboxylic acid (9), 6,8-dihydroxy-3-methoxy-1-methyl-anthraquinone-2-carboxylic acid (10), methyl 3,8-dihydroxy-6-methoxy-1-methyl-anthraquinone-2-carboxylate (11) and methyl 3,7,8-trihydroxy-1-methyl-anthraquinone-2-carboxylate (12).

Phenolic constituents of the rhizomes of the Thai medicinal plant Belamcanda chinensis with proliferative activity for two breast cancer cell lines

From the rhizomes of Belamcanda chinensis, three new compounds, belalloside A (1), belalloside B (2), and belamphenone (3), along with 13 known compounds, resveratrol (4), iriflophenone (5), irisflorentin (6), tectorigenin (7), irilin D (8), tectoridin (9), iristectorin A (10), iristectorin B (11), hispiduloside, androsin, irigenin, iridin, and jaceoside, have been isolated and characterized. Isolates were evaluated for their cell proliferation stimulatory activity against the MCF-7 and T-47D human breast cancer cell lines. Along with 4, 5, 7, and 9, 3 was shown to stimulate not only MCF-7 but also T-47D human breast cancer cell proliferation.

[The index F and relative index Fr of chromatographic fingerprints]

AIM

The index F and relative index Fr of chromatographic fingerprints were firstly proposed to indicate how bountiful was the information in traditional Chinese medicines chromatographic fingerprints, how better was the separation effect, how high was the peak signal and how equal were the peak areas.

METHODS

The index F and relative index Fr of chromatographic fingerprints were firstly applied to evaluate the chromatographic fingerprints results of traditional Chinese medicines determined by the reversed-phase high performance liquid chromatographic method and high performance capillary electrophoresis.

RESULTS

The Shegan Kangbingdu injection and all its traditional Chinese medicines ingredients had been evaluated by F and Fr, so did for the HPLC fingerprints of Radix salviae miltiorrhizae reported in literature. As the same time, the F and Fr of the capillary electrophoresis fingerprints of Folium isatidis, Rhizoma belamcandae and compound liquorice tablets were successfully determined. As far as F was concerned, there was no evident difference between HPLC and capillary electrophoresis (CE), but the Fr values came from CE was usually a thousand times more than that from HPLC.

CONCLUSION

The F and Fr can be applied to evaluate objectively, simply and thoroughly the chromatographic fingerprints.

[The process study on the extraction of irone by supercritical fuilds extraction]

OBJECTIVE

To study the condition for the extraction of irone in Iris tectorum by supercritical fluids extraction.

METHOD

Conditions for the extraction were studied by a systematic method as guided by the content of irone presented in the extract.

RESULTS

The best SFE conditions were: 0.411 mm raw material powder of Iris tectorum, 3% CHCl3 as modifier, temperature of extraction 50 degrees C under the pressure of 25 MPa, with CO2 flow rate of 120L/h, the static extracting time 2 h.

Antioxidant activities of isoflavones from the rhizomes ofbelamcanda chinensis on carbon tetrachloride-lnduced hepatic injury in rats

The present study was carried out to clarify whether tectorigenin and tectoridin isolated from the rhizomes of Belamcanda chinensis (Iridaceae) inhibit hepatic damage induced by carbon tetrachloride (CCl4)-intoxication in rats by the experimental methods in vitro and in vivo. Tectorigenin and tectoridin exhibited a significant decrease in serum transaminase activities elevated by hepatic damage induced by CCl4-intoxication in rats, as well as in a lipid peroxidation causing a significant decrease in malondialdehyde (MDA) production by thiobarbituric acid (TBA)-reactant assay. Both compounds also showed strong increase in the antioxidant enzymes such as hepatic cytosolic superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-px) activities in CCl4-intoxicated rats. These results suggested that tectorigenin and tectoridin isolated from the rhizomes of B. chinensis possess not only the antioxidative, but also the hepatoprotective activities in CCl4-intoxicated rats.

A New Anthraquinone fromGladiolus Gandavensis

A new anthraquinone, 1,6,7-trihydroxy-3-methoxyanthraquinone, along with three known compounds methyl trans-p-hydroxycinnamate, eugenin and 1,3,6-trihydroxy-8-methylanthraquinone, were isolated from the subterranean rhizomes of Gladiolus gandavensis Van Houtt. Their structures were established on the basis of spectroscopic data including 2D NMR techniques and chemical methods.

Eleutherinone, a novel fungitoxic naphthoquinone from Eleutherine bulbosa (Iridaceae)

The dichloromethane extract prepared from the underground parts of Eleutherine bulbosa (Miller) Urban (Iridaceae) showed strong activity in the direct bioautography assay with the phytopathogenic fungus Cladosporium sphaerospermum. This assay was used to guide the fractionation of this extract and allowed the isolation of four compounds: the new naphthoquinone eleutherinone[8-methoxy-1-methyl-1,3-dihydro-naphtho(2,3-c)furan-4,9 -dione] and the known compounds, previously isolated from this species, eleutherin [9-methoxy-1(R),3(S)-dimethyl-3,4-dihydro-1H-benzo(g)isochromene-5,10-dione], isoeleutherin [9-methoxy-1(R),3(R)-dimethyl-3,4-dihydro-1H-benzo(g)isochromene-5,10-dione], and eleutherol [4-hydroxy-5-methoxy-3(R)-methyl-3H-naphtho(2,3-c)furan-1 -one]. All quinonoid compounds showed strong antifungal activity in the bioautography assay at 100 g/spot, while eleutherol was inactive.

Antiplasmodial and antifungal activities of iridal, a plant triterpenoid

Iridal, a triterpenoidic compound extracted from Iris germanica L., was previously shown to have an interesting activity on two cultured human tumor cell lines (A2780 and K562). In the present work, this same product was tested in vitro on Plasmodium falciparum chloroquine-resistant and -sensitive strains, in vivo on P. vinckei, and on some Candida albicans and C. parapsilosis strains too. The IC(50) obtained in vitro on human malaria strain ranged from 1.8 to 26.0 microg/ml and the ED(50) in vivo is about 85 mg/kg/day by intraperitoneal route. The minimal inhibitory concentrations were higher than to 50 microg/ml, whatever the strain of yeast tested. This product presents an antiplasmodial activity similar to that obtained with extracts from the plant Azadirachta indica classically taken as reference in malaria phytomedicine. Conversely iridal shows no important antifungal activity. The specific activity of iridal on human malaria parasite and on tumor cell lines is discussed.

Alkylated benzoquinones from Iris kumaonensis

Six novel alkylated p-Benzoquinones irisoquin (A-F) (1-2, 4-7) together with a known cytotoxic quinone, irisoquin (3) along with three known isoflavones, tectoregenin, iristectorin and irigenin were isolated from the rhizomes of Iris kumaonensis and characterized. The structures of compounds 1-2, 4-7 were confirmed by extensive spectroscopic analysis, IR, MS, HRMS, GC, GC-MS, 1D (1H, 13C, NOE) and 2D (HMQC and HMBC) NMR and comparison with literature data of known compounds.

Iridal glycosides from Iris spuria (Zeal), cultivated in Egypt

Fractionation of a methanol extract obtained from rhizomes of I. spuria (Zeal) resulted in the isolation of seven iridalglycosides 5a,b, 6a-c, 7, 8. The structures of the aglycons and the position of the glycosidic bonds were elucidated by spectroscopic analyses. The nature of the sugar moieties was determined as glucose from capillary GC and GC/MS analyses after hydrolysis of the compounds, reduction and derivatization of the resulting hexitols in comparison to authentic standards. Methylation analysis revealed the glycosyl-linkage composition. The number and position of the glucose residues was determined by ozonolysis.

Isoflavonoids from the rhizomes of Belamcanda chinensis and their effects on aldose reductase and sorbitol accumulation in streptozotocin induced diabetic rat tissues

Aldose reductase, the key enzyme of the polyol pathway, is known to play important roles in the diabetic complication. The inhibitors of aldose reductase, therefore, would be potential agents for the prevention of diabetic complications. To evaluate active principles for the inhibition of aldose reductase from the rhizomes of Belamcanda chinensis, twelve phenolic compounds were isolated and tested for their effects on rat lens aldose reductase. As a result, isoflavones such as tectorigenin, irigenin and their glucosides were found to show a strong aldose reductase inhibition. Tectoridin and tectorigenin, exhibited the highest aldose reductase inhibitory potency, their IC50 values, being 1.08 x 10(-6) M and 1.12 x 10(-6) M, respectively, for DL-glyceraldehyde as a substrate. Both compounds, when administered orally at 100 mg/kg for 10 consecutive days to streptozotocin-induced diabetic rats, caused a significant inhibition of sorbitol accumulation in the tissues such as lens, sciatic nerves and red blood cells. Tectorigenin showed a stronger inhibitory activity than tectoridin. From these results, it is suggested that tectorigenin is attributed to be a promising compound for the prevention and/or treatment of diabetic complications.

Protein kinase C activation by iridal type triterpenoids

Eleven iridal type triterpenoids from Iris tectorum and Belamcanda chinensis were examined for protein kinase C (PKC) activation and binding activity to PKC. Among the tested compounds, nine iridals showed dose-dependent activities, and a mutual relation between the two activities was also observed. 28-Deacetylbelamcandal, which has been found to be a new class 12-O-tetradecanoylphorbol 13-acetate type tumor promoter, showed the most potent activity in both tests. The structural requirements of the iridals inducing these activities were as follows: 1) a hydrophobic side-chain, 2) an E-methylidene aldehyde group at the C-1 position, and 3) a hydroxyl group at the C-26 position.

Iridals are a novel class of ligands for phorbol ester receptors with modest selectivity for the RasGRP receptor subfamily

Since 1990, the National Cancer Institute has performed extensive in vitro screening of compounds for anticancer activity. To date, more than 70 000 compounds have been screened for their antiproliferation activities against a panel of 60 human cancer cell lines. We probed this database to identify novel structural classes with a pattern of biological activity on these cell lines similar to that of the phorbol esters. The iridals form such a structural class. Using the program Autodock, we show that the iridals dock to the same position on the C1b domain of protein kinase C delta as do the phorbol esters, with the primary hydroxyl group of the iridal at the C3 position forming two hydrogen bonds with the amide group of Thr12 and with the carbonyl group of Leu 21 and the aldehyde oxygen of the iridal forming a hydrogen bond with the amide group of Gly23. Biological analysis of two iridals, NSC 631939 and NSC 631941, revealed that they bound to protein kinase C alpha with K(i) values of 75.6 +/- 1.3 and 83.6 +/- 1.5 nM, respectively. Protein kinase C is now recognized to represent only one of five families of proteins with C1 domains capable of high-affinity binding of diacylglycerol and the phorbol esters. NSC 631939 and NSC 631941 bound to RasGRP3, a phorbol ester receptor that directly links diacylglycerol/phorbol ester signaling with Ras activation, with K(i) values of 15.5 +/- 2.3 and 41.7 +/- 6.5 nM, respectively. Relative to phorbol 12,13-dibutyrate, they showed 15- and 6-fold selectivity for RasGRP3. Both compounds caused translocation of green fluorescent protein tagged RasGRP3 expressed in HEK293 cells, and both compounds induced phosphorylation of ERK1/2, a downstream indicator of Ras activation, in a RasGRP3-dependent fashion. We conclude that the iridals represent a promising structural motif for design of ligands for phorbol ester receptor family members.

Five new peltogynoids from underground parts of Iris bungei: a Mongolian medicinal plant

Five new peltogynoids, irisoids A-E (1-5), have been isolated from the underground parts of Iris bungei. The structures of the new compounds were established on the basis of spectroscopic methods and were found to be 1,8,10-trihydroxy-9-methoxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (1), 1,8-dihydroxy-9,10-dimethoxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (2), 1,10-dihydroxy-8,9-dimethoxy-[1]benzopyrano-13,2-c][2]-benzopyran-7(5H)-one (3), 1,8-dihydroxy-9,10-methylenedioxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (4), and 1,8,11-trihydroxy-9,10-methylenedioxy-[1]benzopyrano-[3,2-c][2]-benzopyran-7(5H)-one (5). The structure of irisoid B (2) was established unambiguously by X-ray diffraction study.

Isoflavonoids from Belamcanda chinensis

Four new isoflavonoids were isolated along with six known related compounds from a rhizome of Belamcanda chinensis (Iridaceae), and their structures were characterized as 6''-O-p-hydroxybenzoyliridin, 6''-O-vanilloyliridin, 5,6,7,3'-tetrahydroxy-4'-methoxyisoflavone and 2,3-dihydroirigenin, respectively, on the basis of spectroscopic methods and chemical evidence.