Steroidal saponins from fresh stem of Dracaena cochinchinensis

Steroidal saponins and homoisoflavonoids from the fibrous roots of ophiopogon japonicus and their anti-pulmonary fibrosis activities

The chemical investigation of the fibrous roots of Ophiopogon japonicus afforded two new steroidal saponins, named ophiojaponin F (1) and ophiojaponin G (2), together with twelve known steroidal saponins (3-14) and ten known homoisoflavonoids (15-24). The structures of the isolated compounds were established unambiguously via spectroscopic analyses (NMR and HR-ESI-MS). Ophiojaponin F (1) is a 23-hydroxylated spirostanol saponin, and this type of steroidal saponin rarely been reported in liriopogons. All isolates were evaluated for their anti-pulmonary fibrosis activities on TGF-β1-actived NIH3T3 cells for the first time. Among them, compounds 3, 4, 11-13, 15-19, 21 and 24 showed potential anti-pulmonary fibrosis effects with IC50 values ranging from 3.61 ± 0.86 μM to 21.33 ± 1.82 μM, and the main component ophiopogonin D (4) displayed the best activity with an IC50 value of 3.61 ± 0.86 μM. Thus, ophiopogonin D may be a potent candidate for the treatment of pulmonary fibrosis.

Polypunctosides E-K: seven new steroidal saponins from Polygonatum punctatum Royle ex Kunth and their nitric oxide production inhibitory activities

Polygonatum punctatum Royle ex Kunth is a high-value medicinal plant found in old natural forests. A phytochemical study on the roots of this plant led to the isolation of seven new steroidal saponins including four furostans (1-4) and three furospirostans (5-7). Their structures were elucidated as (25R)-26-O-(β-D-glucopyranosyl)-furost-5-ene-3β,17α,22α,26-tetraol 3-O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 4)-β-D-galactopyranoside (1), (25R)-26-O-(β-D-glucopyranosyl)-furost-5-ene-3β,14α,17α,22α,26-pentaol 3-O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 4)-β-D-galactopyranoside (2), (25R)-26-O-(β-D-glucopyranosyl)-furost-5-ene-22α-methoxy-3β,17α,26-triol 3-O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 4)-β-D-galactopyranoside (3), (25R)-26-O-(β-D-glucopyranosyl)-furost-5-ene-22α-methoxy-3β,17α,26-triol 3-O-[α-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 4)]-[acetoxy-(→ 6)]-β-D-galactopyranoside (4), 26-O-(β-D-glucopyranosyl)-14α,17α-dihydroxynuatigenin 3-O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 4)-β-D-galactopyranoside (5), 26-O-(β-D-glucopyranosyl)-17α-hydroxynuatigenin 3-O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 4)-β-D-galactopyranoside (6), and 26-O-(β-D-glucopyranosyl)-14α-hydroxynuatigenin 3-O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 4)-β-D-galactopyranoside (7) by extensive spectroscopic analyses, including infrared, high-resolution electrospray ionization mass spectrometry, and one- and two-dimensional nuclear magnetic resonance spectroscopy. Compounds 1-7 inhibited nitric oxide production in lipopolysaccharide activated RAW264.7 cells with IC₅₀ values ranging from 41.5 ± 3.2 to 62.2 ± 3.7 µM, compared to 33.8 ± 2.6 µM for the positive control compound L-NMMA.

Astramalabaricosides A-T, Highly Oxygenated Malabaricane Triterpenoids with Migratory Inhibitory Activity from Astragalus membranaceus var. mongholicus

Twenty new malabaricane triterpenoids, astramalabaricosides A-T (1-20), were isolated from the roots of Astragalus membranaceus var. mongholicus (Astragali Radix). Their structures were determined by spectroscopic analysis, and the use of the circular dichroism exciton chirality method, quantum chemical calculations, and chemical methods. Malabaricane triterpenoids, an unusual group with the 6-6-5-tricyclic core, are distributed in plants (e.g., Simaroubaceae, Polypodiaceae, and Fabaceae), a marine sponge, and fungi, and their number obtained to date is limited. Compounds 1-20 were characterized as glycosides with a highly oxygenated side chain, and 13-20 were the first cyclic carbonate derivatives among the malabaricane triterpenoids. The stereocluster formed from the continuous hydroxylated chiral carbons in each highly oxygenated side chain and the 6-6-5-tricyclic core system were entirely segregated, and the independent identification of their stereoconfigurations required considerable effort. The migratory inhibitory and antiproliferative activities of 1-20 were evaluated by wound-healing and cell-viability assays, respectively. Most compounds showed significant migratory inhibitory activity, and a preliminary structure-activity relationship was developed. Malabaricane triterpenoids are being reported in the genus Astragalus for the first time.

Steroidal Saponins─New Sources to Develop Potato (Solanum tuberosum L.) Genotypes Resistant against Certain Phytophthora infestans Strains

Plant pathogens such as Phytophthora infestans that caused the Irish Potato Famine continue to threaten local and global food security. Genetic and chemical plant protection measures are often overcome by adaptation of pathogen population structures. Therefore, there is a constant demand for new, consumer- and environment-friendly plant protection strategies. Metabolic alterations induced by P. infestans in the foliage and tubers of six different potato cultivars were investigated. Using a combination of untargeted metabolomics, isolation techniques, and structure elucidation by MS and 1D/2D-NMR experiments, five steroidal glycoalkaloids, five oxylipins, and four steroidal saponins were identified. As the steroidal saponins showed antioomycete but no hemolytic activity, they may thus be considered as probably safe target substances for enrichment in breeding programs for disease resistance and as chemical lead structures for the production of nature-derived synthetic antioomycetes.

In vitro wound healing properties, antioxidant activities, HPLC-ESI-MS/MS profile and phytoconstituents of the stem aqueous methanolic extract of Dracaena reflexa Lam

Column chromatography of the stem aqueous methanolic extract of Dracaena reflexa Lam. (DRSE) led to the isolation of five flavonoids, one phenolic glycoside, one triterpenoid, and two steroidal saponins. Furthermore, forty-four compounds were tentatively identified in the phytoconstituents profile of DRSE using HPLC-ESI-MS/MS. The antioxidant activity of DRSE was evaluated. In DPPH radical scavenging assay, DRSE exhibited IC₅₀ value 311.6 ± 10.10 μg/mL compared to IC₅₀ value of the standard Trolox (24.42 ± 0.87 μg/mL). The antioxidant activities of DRSE using ABTS assay and FRAP assay were 326.63 μM TE/mg extract and 208.67 μM TE/mg extract, respectively. The wound healing activity of DRSE was studied by the scratch assay using HSF (Human Skin Fibroblast) cells. After 24 hrs. DRSE (at 10 and 20 μg/mL) decreased the wound width to 0.55 ± 0.37 and 0.47 ± 0.55 mm, respectively, compared to the wound width in the control cells (0.77 ± 0.17 mm). This result suggested that DRSE improved the wound healing process by inducing the migration of fibroblasts. Moreover, a docking study was performed to evaluate the binding affinity of the identified phytoconstituents toward GSK-3β relative to the co-crystalized inhibitor and curcumin with the possible involvement of this pathway in the wound healing activity of the extract.

Spirostane saponins with a rearranged A/B ring system isolated from the rhizomes of Ophiopogon japonicus

In this study, the popular food and medicinal herb Ophiopogon japonicus was investigated alongside a 70% ethanol extract of its rhizomes, revealing twenty-three steroidal glycosides with four undescribed steroidal saponins, named ophiopogonols A-D. Among them, ophiopogonols A-B are two unusual spirostanols with a rearranged A/B ring system (5/7/6/5/5/6 ring system) that have not previously been identified in plants. The chemical structures of all isolated steroidal glycosides were elucidated by comprehensive analysis through chemical methods, HRESIMS, and NMR spectroscopy. Further, putative biosynthetic pathways for ophiopogonols A-B were proposed. In addition, based on traditional applications of O. japonicus, cytotoxic effects of the isolates were evaluated using human large cell lung carcinoma cells (NCI-H460 cells). Sprengerinin C displayed a remarkable cytotoxic effect with IC₅₀ values of 2.1 ± 0.8 μM by inducing apoptosis and G2/M phase cycle arrest in the NCI-H460 cell line.

Cytotoxic steroidal glycosides from Polygonatum odoratum (Mill.) Druce

Twenty-five steroidal glycosides including eight undescribed compounds which were named as polygonatumosides H-O, were isolated from the 70 % EtOH extract of rhizomes of Polygonatum odoratum (Mill.) Druce (Asparagaceae). Their structures were elucidated by extensive spectroscopic analyses and chemical methods. The isolated compounds were evaluated cytotoxicity against three human cancer cell lines: human non-small cell lung cancer (A549), human epithelial colorectal adenocarcinoma (Caco2), and human hepatocellular carcinoma (HepG2) cells. Five compounds showed cytotoxicity against these cell lines with IC₅₀ values in the range of 1.7-30.8 μM.

Dragon's Blood from Dracaena Worldwide: Species, Traditional Uses, Phytochemistry and Pharmacology

Dragon's blood (DB) refers mainly to the crimson resin of many Dracaena spp. DB has been used by different traditional medicine systems worldwide, including Arabic medicine, African medicine, traditional Chinese medicine, Thai medicine, etc. DB are mainly used to heal wounds, kill pain, stop bleeding, and cure various diseases such as diarrhea, dysentery and ulcers for over 1000 years. 11 Dracaena spp. and 3 subspecies are reported to be able to produce red resin. However, the resources are extremely deficient. Several Dracaena spp. are in threatened status. Over 300 compounds have been isolated from Dracaena spp., mainly including flavonoids, steroids, and phenolics. DB exhibits anti-inflammatory, analgesic, antithrombotic, anti-oxidant, antimicrobial, antidiabetic, and anticancer properties, which explain its wound healing effects, preventive effects on cardiovascular and cerebrovascular diseases, dual-directional regulation of blood flow, neuroprotection and radioprotective effects. No apparent side effects or toxicity have been reported. DB are restricted from being exploited due to limited resources and unclear resin formation mechanism. It is necessary to expand the cultivation of Dracaena spp. and fully understand the mechanism underlying the resin formation process to develop an effective induction method for the sustainable utilization of DB.

Structures and Bioactivities of Steroidal Saponins Isolated from the Genera Dracaena and Sansevieria

The species Dracaena and Sansevieria, that are well-known for different uses in traditional medicines and as indoor ornamental plants with air purifying property, are rich sources of bioactive secondary metabolites. In fact, a wide variety of phytochemical constituents have been isolated so far from about seventeen species. This paper has reviewed the literature of about 180 steroidal saponins, isolated from Dracaena and Sansevieria species, as a basis for further studies. Saponins are among the most characteristic metabolites isolated from the two genera. They show a great variety in structural motifs and a wide range of biological activities, including anti-inflammatory, anti-microbial, anti-proliferative effects and, in most case, remarkable cytotoxic properties.

A Convenient Synthesis of (16S,20S)-3β-Hydroxy-5α-pregnane-20,16-carbolactam and Its N-alkyl Derivatives

A concise synthesis of (16S,20S)-3β-hydroxy-5α-pregnane-20,16-carbolactam from tigogenin via the corresponding lactone is described. The most efficient synthetic route consisted of the lactone ring-opening with aminoalane reagent followed by PDC or Dess-Martin oxidation. The oxo-amide obtained was subjected to cyclization with Et₃SiH/TFA or Et₃SiH/Bi(TfO)₃. Alternately, the lactone was converted first to the oxo-acid, which was then subjected to the microwave-assisted reductive amination. N-Alkyl derivatives were also obtained in a similar way.

Synthesis and application of steroidal 22,16β-carbolactones: A review

In the plant kingdom, steroidal lactones occur as glycosides, compounds consisting of a sugar moiety linked to a steroid aglycone. Steroidal lactones consist of five fused rings, with a total of 22 carbon atoms. Numerous methods for the preparation of steroidal lactones take advantage of the fact that steroid spirostanes may be degraded from six- to a five-rings structure. One of the most striking features common to reactions of steroid sapogenins is the C₂₂-lactone formation. In the review, different methods for the preparation of steroidal lactones are presented with consideration of the structure of starting material. In addition, examples of lactones used in the synthesis of biologically active compounds and their analogues are described.

Dragon’s Blood from Dracaena cambodiana in China: Applied History and Induction Techniques toward Formation Mechanism

Dragon’s blood that is extracted from Dracaena plants has been widely used as traditional medicine in various ancient cultures. The application of dragon’s blood has a cherished history in China, even though the original plants were not discovered for some period. Dracaena cochinchinensis and Dracaena cambodiana were successively discovered in southern China during the 1970s–1980s. In the last half of the century, Chinese scientists have extensively investigated the production of dragon’s blood from these two Dracaena species, whereas these results have not been previously systematically summarized, as in the present paper. Herein, we present the applied history in ancient China and artificially induced technologies for dragon’s blood development based on these two Dracaena species, in particular, using tissue cultures seedlings and tender plants of D. cambodiana. Big data research, including transcriptomic and genomic studies, has suggested that dragon’s blood might be a defense substance that is secreted by Dracaena plants in response to (a)biotic stimuli. This review represents an effort to highlight the progress and achievements from applied history as well as induction techniques that are used for the formation of dragon’s blood that have taken place in China. Such knowledge might aid in the global conservation of wild Dracaena species and contribute to understanding dragon blood formation mechanisms, eventually assisting in the efficient utilization of limited Dracaena plant resources for the sustainable production of dragon’s blood.

What We Know and What We Do Not Know about Dragon Trees?

This article is a broad review focused on dragon trees—one of the most famous groups of trees in the world, well known from ancient times. These tertiary relicts are severely endangered in most of the area where they grow. The characteristic features of the dragon tree group are described and the species belonging to this group are listed. This review gathers together current knowledge regarding the taxonomy, evolution, anatomy and morphology, physiology, and ontogeny of arborescent dragon tree species. Attention is also paid to the composition, harvesting, medicinal, and ethnobotanical use of the resin (dragons’ blood). An evaluation of population structure, distribution, ecology, threats, and nature conservation forms the final part of the review. In the conclusions we recommend further avenues of research that will be needed to effectively protect all dragon tree species.

Antiproliferative steroidal glycosides from rhizomes of Polygonatum sibiricum

Screening assays showed that total glycoside-rich fraction (TG) of rhizomes of Polygonatum sibiricum unveiled remarkable anti-proliferative activities against three cancer cell lines (A549, HepG2, and Caco2). Activity-guided isolation of TG afforded seven undescribed steroidal glycosides (polygonosides 1-7), along with 24 known glycosides. Their structures were established by 1D and 2D NMR spectroscopic analyses, high-resolution mass spectrometry, and chemical evidence. The isolated steroidal glycosides were tested for their antiproliferative activities against A549, HepG2, and Caco2 cells. Compounds 8, 10, 11, and 16 possessed stronger anticancer activities against A549 cells than the positive control Bay (25.8 μM), with IC₅₀ values ranging from 5.8 to 24.2 μM. Compound 10 reduced the expression of Blc-2 and pro-caspase3 and increased the production of Bax as determined by western blotting. Molecular docking experiment suggested that 10 bound stably to the BH3-binding groove of the Bcl-2 protein by hydrogen bond interactions. These compounds could be candidates for anticancer agents with cytotoxic activity.

Rapid Evaluation of Chemical Consistency of Artificially Induced and Natural Resina Draconis Using Ultra-Performance Liquid Chromatography Quadrupole-Time-of-Flight Mass Spectrometry-Based Chemical Profiling

Resina Draconis is a highly valued traditional medicine widely used in Arabia since ancient times, and it has been commonly used as an antidiarrheic, antimicrobial, antiulcer, blood circulation promoter as well as an anti-inflammatory agent. The tree source from which this medicine orignates grows extremely slowly, producing a very low yield of Resina Draconis. To meet the increasing market demand, artificial methods for stimulating Resina Draconis formation have been developed and applied. However, the chemical differences between artificially induced Resina Draconis (AIRD) and natural Resina Draconis (NRD) have been rarely studied. The aim of this research was to explore and identify the chemical constituents of AIRD and NRD using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS) based chemical profiling. A total of 56 chromatographic peaks were detected in AIRD, of these, 44 peaks have had their structures tentatively characterized based on high-resolution mass spectra (HRMS) data, fragmentation ions information, reference standards data and literature review. In total, 40 peaks were found both in AIRD and NRD. The potential chemical transformation mechanisms active in Resina Draconis during formation were explored. To the best of our knowledge, this is the first evaluation of the chemical profiles of both AIRD and NRD. Furthermore, these findings are expected to provide a rational basis for the quality assessment of AIRD and the use of AIRD as a substitute for NRD.

Identification, characterization and expression analysis of genes involved in steroidal saponin biosynthesis in Dracaena cambodiana

Dracaena cambodiana is a traditional medicinal plant used for producing dragon's blood. The plants and dragon's blood of D. cambodiana contain a rich variety of steroidal saponins. However, little is known about steroidal saponin biosynthesis and its regulation in D. cambodiana. Here, 122 genes encoding enzymes involved in steroidal saponin biosynthesis were identified based on transcriptome data, with 29 of them containing complete open reading frames (ORF). Transcript expression analysis revealed that several genes related to steroidal saponin biosynthesis showed distinct tissue-specific expression patterns; the expression levels of genes encoding the key enzymes involved in the biosynthesis and early modification of steroidal saponins were significantly down-regulated in the stems in response to the inducer of dragon's blood, exhibiting positive correlations with the content of steroidal saponins. These results provide insights on the steroidal saponins biosynthetic pathway and mechanisms underlying induced formation of dragon's blood in D. cambodiana.

The synthesis and antifungal activity of (20S)-3β-acetoxy-5α-pregnane-20,16β-carbolactone against fluconazole - Resistant Candida cells

An efficient procedure for the synthesis of (20S)-3β-acetoxy-5α-pregnane-20,16β-carbolactone is described. Bactericidal and fungicidal activity of the lactone against different bacteria such as MSSA, MRSA, E. coli ESBL, P. aeruginosa and clinical isolates of Candida spp., in planktonic and biofilm growth stage were assessed. Additionally, the affinity of this new compound to microbial plasma membrane and hemoglobin release from human red blood cells were determined using fluorometric and colorimetric assay, respectively. Our studies revealed that the lactone exhibits strong antifungal activity, and the ability to prevent pathogens' biofilm formation. Additionally, upon lactone treatment a significant affinity to fungal, but not to human cell membranes, indicating suitable biocompatibility was observed.

Chalcane-stilbene conjugates and oligomeric flavonoids from Chinese Dragon's Blood produced from Dracaena cochinchinensis

A detailed chemical investigation of Chinese Dragon's Blood, which is a traditional medicine produced form the red resin of Dracaena cochinchinensis, yielded two chalcane-stilbene conjugates, named cochinchinenenes G and H, together with 25 known compounds. The structures of these compounds were determined by spectroscopic examination. HPLC analysis of the resin indicated that the major constituents were a complex mixture of oligomeric polyphenols, which were detected as a broad hump on the base line of a HPLC chromatogram. (13)C NMR analysis indicated that the oligomers were mainly composed of oxygenated chalcane units. This suggestion was supported by the results of a thiol degradation experiment with mercaptoethanol, which yielded a thioether of 4-[(4-hydroxyphenyl)propyl]-3-methoxyphenol. Furthermore, methylation followed by electrospray ionization mass spectroscopic analysis of the resulting fractions established the presence of at least one heptamer of chalcane units.

Steroidal saponins from the rhizomes of Polygonatum prattii

Seven steroidal saponins including two new furostanol glycosides were isolated from the rhizomes of Polygonatum prattii collected from Panzhihua, Sichuan province of China. The new compounds were determined as 26-O-β-d-glucopyranosyl-(25R)-3β,22ξ-dihydroxy-furost-5-en-7-one (pratioside G) and 26-O-β-D-glucopyranosyl-(25R)-22ξ-hydroxy-furost-5-en-3β-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (pratioside H), on the basis of detailed spectroscopic and chemical analysis.

Spirostane-type Saponins from Dracaena fragrans « Yellow Coast »

Three steroidal glycosides were isolated from the bark of Dracaena fragrans (L.) Ker Gawl. « Yellow Coast », and a fourth from the roots and the leaves. Their structures were characterized on the basis of extensive 1D and 2D NMR experiments and mass spectrometry, and by comparison with NMR data of the literature. These saponins have the spirostane-type skeleton and are reported in this species for the first time.

Simultaneous quantification of five steroid saponins from Dioscorea zingiberensis C.H. Wright in rat plasma by HPLC-MS/MS and its application to the pharmacokinetic studies

A simple, reliable and sensitive high-performance liquid chromatography tandem mass spectrometry method (HPLC-MS/MS) was established for simultaneous analyses of the following 5 steroid saponins in rat plasma after the single dose administration of total steroid saponins extracted from the rhizome of Dioscorea zingiberensis C.H. Wright for the first time. Protodioscin, huangjiangsu A, zingiberensis new saponin, dioscin, and gracillin were quantified using ginsenoside Rb1 as the internal standard (IS). The plasma samples were pretreated by a single step acetonitrile-mediated protein precipitation. The chromatographic separation was performed on an Inersil ODS-3 C18 column (250mm×4.6mm, 5μm) with the mobile phase composed of acetonitrile and water containing 0.1% formic acid under a gradient elution mode at 0.2mLmin(-1) using a microsplit after the eluent from the HPLC apparatus. The quantification was accomplished on a triple quadrupole tandem mass spectrometer using the multiple reaction monitoring (MRM) in the positive ionization mode. The above five analytes were stable under sample storage and preparation conditions applied in the present study. The linearity, precision, accuracy, and recoveries of the analysis confirmed the requirements for quality-control purposes. After validation, this proposed method was successfully adopted to investigate the pharmacokinetic parameters of these five analytes.

Studies on chemical constituents of Ophiopogon japonicus

Two new and six known steroidal glucosides were isolated from the tuber of Ophiopogon japonicus. The new steroidal glucosides were established as (20R,25R)-26-O-β-d-glucopyranosyl-3β,26-dihydroxycholest-5-en-16,22-dioxo-3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-glucopyranoside (1) and 26-O-β-d-glucopyranosyl-(25R)-furost-5-en-3β,14α,17α,22α,26-pentaol-3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-glucopyranoside (3) on the basis of spectroscopic data as well as chemical evidence.

Natural potential therapeutic agents of neurodegenerative diseases from the traditional herbal medicine Chinese dragon's blood

ETHNOPHARMACOLOGICAL RELEVANCE

Dragon's blood has been used as a famous traditional medicine since ancient times by many cultures. It is a deep red resin, obtained from more than 20 different species of four distinct genera. Red resin of Dracaena cochinchinensis S.C. Chen, known as Chinese dragon's blood or Yunnan dragon's blood, has been shown to promote blood circulation, alleviate inflammation, and to treat stomach ulcers, diarrhea, diabetes, and bleeding. This study investigated an effective approach to identify natural therapeutic agents for neurodegeneration from herbal medicine. The dichloride extract and isolated effective constituents of Chinese dragon's blood showed quinone oxidoreductase 1 (NQO1) inducing activity and anti-inflammatory effect significantly, which are therapy targets of various neurodegenerative diseases.

MATERIALS AND METHODS

Multiple chromatography and spectra analysis were utilized to afford effective constituents. Then Hepa 1c1c7 and BV-2 cells were employed to assay their NQO1 inducing and anti-inflammatory activities, respectively.

RESULTS

Bioactivities guided isolation afforded 21 effective constituents, including two new polymers cochinchinenene E (1), cochinchinenene F (2) and a new steroid dracaenol C (16). The main constituent 3 (weight percent 0.2%), 5 (weight percent 0.017%), 4 (weight percent 0.009%), 9 (weight percent 0.094%), 10 (weight percent 0.017%) and 8 (weight percent 0.006%) are responsible for the anti-inflammatory activities of Chinese dragon's blood. While, new compounds 1, 2 and known compounds 5, 11 showed good NQO1 inducing activities. The brief feature of the activities and structures was discussed accordingly.

CONCLUSION

Overviewing the bioactivities and phytochemical study result, 4'-hydroxy-2,4-dimethoxydihydrochalcone (3) and pterostilbene (5) as effective constituents of Chinese dragon's blood, were found to be potential candidate therapeutic agents for neurodegenerative diseases.

Chemical fingerprint analysis and quantitative determination of steroidal compounds from Dioscorea villosa, Dioscorea species and dietary supplements using UHPLC-ELSD

Ultra high-performance liquid chromatography (UHPLC) with evaporative light scattering detection was used for the quantification of steroidal saponins and diosgenin from the rhizomes or tubers of various Dioscorea species and dietary supplements that were purported to contain Dioscorea. The analysis was performed on an Acquity UPLC™ system with an UPLC™ BEH Shield RP18 column using a gradient elution with water and acetonitrile. Owing to their low UV absorption, the steroidal saponins were observed by evaporative light scattering detection. The 12 compounds could be separated within 15 min using the developed UHPLC method with detection limits of 5-12 µg/mL with 2 μL injection volume. The analytical method was validated for linearity, repeatability, accuracy, limits of detection and limits of quantification. The relative standard deviations for intra- and inter-day experiments were <3.1%, and the recovery efficiency was 97-101%. The total content of standard compounds was found to be in the ranges 0.01-14.5% and 0.9-28.6 mg daily intake for dry plant materials and solid commercial preparations, respectively. UHPLC-mass spectrometry with a quadrupole mass analyzer and ESI source was used only for confirmation of the identity of the various saponins. The developed method is simple, rapid and especially suitable for quality control analysis of commercial products.

Steroidal saponins from dragon's blood of Dracaena cambodiana

Six new steroidal saponins, cambodianosides A-F (1-6), together with seven known ones, were isolated from the dragon's blood of Dracaena cambodiana. The structures of 1-6 were elucidated on the basis of detailed spectroscopic analysis, including 1D and 2D NMR techniques and chemical methods. The cytotoxicities of all the isolated compounds were evaluated in vitro against three human cancer cell lines, and compounds 7, 8, and 11 showed significant inhibitory activities.

Cholestane steroid glycosides from the rhizomes of Dioscorea villosa (wild yam)

Phytochemical investigation of the MeOH extract of Dioscorea villosa rhizomes resulted in the isolation of two new bidesmosidic cholestane steroid glycosides, dioscoreavillosides A and B (1 and 2). In addition, the extract yielded 12 previously known furostan and spirostan steroid glycosides (3-14), along with diosgenin (15). Compounds 3-7, 9, 14, and 15 were isolated for the first time from D. villosa. The structures of the isolated compounds were determined using spectroscopic and chemical methods including 1D and 2D NMR. The antimicrobial action of most of these compounds was tested against five fungal and five bacterial strains.

7-Oxodioscin, a New Spirostan Steroid Glycoside from the Rhizomes of Dioscorea nipponica

Nine glycosides of spirostan (1–7) and furostan (8 and 9) type steroids including a new compound, 7-oxodioscin (1), were isolated from the rhizomes of Dioscorea nipponica. The structure of 1 was established as (25 R)-3β -O-[(α-L-rhamnopyranosyl-(1→4)- O-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranosyl)oxy]spirost-5-en-7-one by extensive spectroscopic techniques including HRESI-TOFMS, 1D and 2D NMR, and chemical methods. Known compounds were elucidated as dioseptemloside G (2), (25 R)-dracaenoside G (3), orbiculatoside B (4), dioscin (5), progenin III (6), gracillin (7), (3β,22α,25 R)–26-(β-D-glucopyranosyloxy)-22-methoxyfurost-5-en-3-yl O-[α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranoside (8), and methylprotodioscin (9).

Steroidal Saponins from Dracaena marginata

Three new steroidal saponins and ten known ones were isolated from the bark of Dracaena marginata, along with two known steroidal saponins from the roots. Their structures were elucidated on the basis of extensive 1D and 2D NMR experiments and mass spectrometry as (25R)-26-(β-D-glucopyranosyloxy)- 3β,22α-dihydroxyfurost-5-en-1β-yl O-α-L-rhamnopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→-4)]-β-D-glucopyranoside (1), (25R)-26-(β-D-glucopyrano- syloxy)-3β,22α-dihydroxyfurost-5-en-1β-yl O-α-L-rhamnopyranosyl-(1→-2)-4-O-sulfo-α-L-arabinopyranoside (2), and (25 S)-3β-hydroxyspirost-5-en-1β-yl O- α-L-rhamnopyranosyl-(1→2)-4-O-sulfo-α-L-arabinopyranoside (3).

Cytotoxic steroidal saponins from Ophiopogon japonicus

Four new steroidal saponins, named ophiopogonin P-S (1-4), together with eleven known ones (5-15) were isolated from the tuberous roots of Ophiopogon japonicus. Their structures were elucidated by spectroscopic and chemical analysis. Compounds 2-15 were evaluated for their cytotoxic activity against five human tumor cell lines (HepG2, HLE, BEL7402, BEL7403 and Hela). Compounds 2, 5, 6, 8 and 9 were cytotoxic for all cell lines tested. Compounds 7, 11 and 15 showed selective cytotoxicity against some of the cell lines. The structure-activity relationship of these compounds was discussed.

Identification of Sensory-Active Phytochemicals in Asparagus (Asparagus officinalis L.)

Sensory-directed fractionation of extracts prepared from raw and cooked asparagus (Asparagus officinalis L.), respectively, followed by LC-TOF-MS, LC-MS/MS, and 1D/2D-NMR experiments revealed the chemical structures of nine bitter tasting mono- and bidesmotic saponins as well as the previously not reported 1,2-dithiolan-4-carboxylic acid 6-D-α/β-glucopyranose ester exhibiting an interesting buttery mouth-coating effect. Sensory studies showed that the orosensation imparted by this sulfur compound was reminiscent to that of melting butter and revealed an orosensory recognition threshold of 276.8 μmol/L.

Structural and Sensory Characterization of Bitter Tasting Steroidal Saponins from Asparagus Spears (Asparagus officinalis L.)

Application of sequential solvent extraction and iterative chromatographic separation in combination with taste dilution analysis recently revealed a series of steroidal saponins as the key contributors to the typical bitter taste of white asparagus spears (Asparagus officinalis L.). Besides six previously reported saponins, (25R)-furost-5-en-3β,22,26-triol-3-O-[α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranoside]-26-O-β-D-glucopyranoside, (25R)-furostane-3β,22,26-triol-3-O-[α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranoside]-26-O-β-D-glucopyranoside, and (25S)-furostane-3β,22,26-triol-3-O-[α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranoside]-26-O-β-D-glucopyranoside, and 3-O-[{α-L-rhamnopyranosyl-(1→2)}{α-L-rhamnopyranosyl-(1→4)}-β-D-glucopyranosyl]-(25S)-spirost-5-ene-3β-ol were identified for the first time as key bitter compounds in the edible spears of white asparagus by means of LC-MS/MS, LC-TOF-MS, 1D/2D-NMR spectroscopy, and hydrolysis experiments. This paper presents the isolation, structure determination, and sensory activity of these saponins. Depending on their chemical structure, the saponins identified showed human bitter recognition thresholds between 10.9 and 199.7 μmol/L (water).

Characterization and identification of steroidal saponins from the seeds of Trigonella foenum-graecum by ultra high-performance liquid chromatography and hybrid time-of-flight mass spectrometry

Ultra high-performance liquid chromatography (UHPLC) coupled with hybrid quadrupole time-of-flight mass spectrometry (Qtof MS(E)) was used to rapidly separate and identify steroidal saponins from the crude extract of the seeds of Trigonella foenum-graecum (TFG). By using the UHPLC/Qtof MS(E) data acquisition strategy, both intact precursor and fragment ion information were obtained from a single injection. Fragmentation rules for five major groups of saponins from TFG are summarized, and possible fragmentation pathways are proposed. Accurate mass measurements of molecular ions and fragment ions as well as retention times permitted the identification or tentative identification of a total of ninety-five saponins based on comparison with reference standards. This included twenty-two pairs of isomers. Thirty of these saponins were identified for the first time.

Steroidal saponins from the tuber of Ophiopogon japonicus

Eight novel steroidal saponins, ophiopogonins H-O (1-8), along with seven known steroidal saponins (9-15) were isolated from the tubers of Ophiopogon japonicus. The structures of these new compounds were determined by detailed spectroscopic analysis, including extensive 1D and 2D NMR data, and the analysis of hydrolytic reaction products. For the first time, rare furostanol saponins with disaccharide moiety linked at position C-26 of the aglycone were reported to be isolated from a natural source.

Flavonoid oligomers from Chinese dragon’s blood, the red resins of Dracaena cochinchinensis

A detailed chemical investigation of the red resins from Dracaena cochinchinensis (Chinese dragon’s blood) yielded five new flavonoid oligomers, named cochinchinenins D-H (1–5), together with a known biflavonoid, cinnabarone (6), and a mixture of two known biflavonoids, socotrin-4′-ol (7) and homoisosocotrin-4′-ol (8). Of these new compounds, 1–3 were biflavonoids and 4 and 5 were triflavonoids. Their structures were determined on the basis of spectroscopic analysis. The isolated compounds were tested for cytotoxicity (Cdc25), antibacterial (PEPT) and antifungal (YNG) activities.

Dragon's blood inhibits chronic inflammatory and neuropathic pain responses by blocking the synthesis and release of substance P in rats

As a traditional Chinese medicine, dragon's blood (DB) is widely used in treating various pains for thousands of years due to its potent anti-inflammatory and analgesic effects. In the present study, we observed that intragastric administration of DB at dosages of 0.14, 0.56, and 1.12 g/kg potently inhibited paw edema, hyperalgesia, cyclooxygenase-2 (COX-2) protein expression, or preprotachykinin-A mRNA expression in carrageenan-inflamed or sciatic nerve-injured (chronic constriction injury) rats, respectively. A short-term (15 s or 10 min) pre-exposure of cultured rat dorsal root ganglion (DRG) neurons to DB (0.3, 3, and 30 µg/ml) or its component cochinchinenin B (CB; 0.1, 1, and 10 µM) blocked capsaicin-evoked increases in both the intracellular calcium ion concentration and the substance P release. Moreover, a long-term (180 min) exposure of cultured rat DRG neurons to DB or CB significantly attenuated bradykinin-induced substance P release. These findings indicate that DB exerts anti-inflammatory and analgesic effects by blocking the synthesis and release of substance P through inhibition of COX-2 protein induction and intracellular calcium ion concentration. Therefore, DB may serve as a promising potent therapeutic agent for treatment of chronic pain, and its effective component CB might partly contribute to anti-inflammatory and analgesic effects.

Dragon's blood: botany, chemistry and therapeutic uses

Dragon's blood is one of the renowned traditional medicines used in different cultures of world. It has got several therapeutic uses: haemostatic, antidiarrhetic, antiulcer, antimicrobial, antiviral, wound healing, antitumor, anti-inflammatory, antioxidant, etc. Besides these medicinal applications, it is used as a coloring material, varnish and also has got applications in folk magic. These red saps and resins are derived from a number of disparate taxa. Despite its wide uses, little research has been done to know about its true source, quality control and clinical applications. In this review, we have tried to overview different sources of Dragon's blood, its source wise chemical constituents and therapeutic uses. As well as, a little attempt has been done to review the techniques used for its quality control and safety.

Anti-Helicobacter pylori and thrombin inhibitory components from Chinese dragon's blood, Dracaena cochinchinensis

Chemical studies on the constituents of Dracaena cochinchinensis led to the discovery of eight new flavonoid derivatives ( 1- 8) along with 14 known compounds ( 9- 22). The identification and structural elucidation of these isolates were based on spectral analyses. All isolates were tested for antibacterial activities against Helicobacter pylori (ATCC43504) and thrombin inhibitory effects. As a result, new flavonoid derivatives 6 and 7 and (2 S)-4',7-dihydroxy-8-methylflavan ( 11) were found to be most efficacious against H. pylori (ATCC43504) with MIC values of 29.5, 29.5, and 31.3 microM, respectively, and the seven new flavonoid derivatives ( 1- 7) and one known biflavonoid ( 9) were observed to exhibit moderate thrombin inhibitory activity.