Steroidal glycosides from the flowers of Allium leucanthum

Furostanol and spirostanol glycosides 1 and 2 were isolated from the flowers of Allium leucanthum, a Caucasian endemic species that grows in Georgia. The structures were established on the base of chemical evidence and spectral analyses ( (1) H, (13) C NMR, (1) H- (1) H COSY, (1) H- (13) C COSY, HMBC, and HR-MS) data. Compound 1 (leucofuranoside A) was reported for the first time and was identified as 26-O-beta-Dglucopyranosyl-(25R)-5 alpha-furostane-3 beta,6 beta-diol-3-O-beta-D-glucopyranosyl-(1 -> 2)-O-beta-D-xylopyranosyl-(1 -> 3)-O-beta-D-glucopyranosyl-(1 -> 4)-beta-D-alactopyranoside. Compound 2 was identified as (25R)-5 alpha-spirostane-3 beta,6 beta-diol-3-O-beta-D-glucopyranosyl-(1 -> 2)-beta-D-glucopyranosyl-(1 -> 4)-beta-D-galactopyranoside and described for the first time in the genus Allium

Antitumor activity of Bulgarian herb Tribulus terrestris L. on human breast cancer cells

Medicinal plants have been intensively studied as a source of antitumor compounds. Due to the beneficial climate conditions Bulgarian herbs have high pharmacological potential. Currently, the antitumor effect of the Bulgarian medicinal plant Tribulus terrestris L. on human cancer cell lines is not studied. The main active compounds of the plant are the steroid saponins.The present study aims to analyze the effect on cell viability and apoptotic activity of total extract and saponin fraction of Bulgarian Tribulus terrestris L. on human breast cancer (MCF7) and normal (MCF10A) cell lines. Antitumor effect was established by МТТ cell viability assay and assessment of apoptotic potential was done through analysis of genomic integrity (DNA fragmentation assay) and analysis of morphological cell changes (Fluorescence microscopy). The results showed that total extract of the herb has a marked dose-dependent inhibitory effect on viability of MCF7 cells (half maximal inhibitory concentration is 15 μg/ml). Cell viability of MCF10A was moderately decreased without visible dose-dependent effect. The saponin fraction has increased inhibitory effect on breast cancer cells compared to total extract. Morphological changes and DNA fragmentation were observed as markers for early and late apoptosis predominantly in tumor cells after treatment. Apoptotic processes were intensified with the increase of treatment duration.The obtained results are the first showing selective antitumor activity of Bulgarian Tribulus terrestris L. on human cancer cells in vitro. Apoptotic processes are involved in the antitumor mechanisms induced by the herb. This results give directions for future investigations concerning detailed assessment of its pharmacological potential

Molecular cloning and bacterial expression of a cDNA encoding furostanol glycoside 26-O-β-glucosidase of Costus speciosus

AbstractFurostanol glycoside 26-O-β-glucosidase (F26G) purified from Costus speciosus rhizomes was digested with endoproteinase, and several internal peptide fragments were obtained. Degenerate oligonucleotide primers based on amino acid sequences of the peptides were used for amplification of F26G cDNA fragments by applying nested polymerase chain reactions to cDNAs from in vitro cultured plantlets of C. speciosus. Using primers based on sequences of the cDNA fragments, the 5′- and 3′-end clones were isolated by rapid amplification of cDNA ends (RACE) methods. Finally, the entire coding portion of F26G cDNA was cloned by using primers designed from sequences of the RACE products. The deduced amino acid sequence of CSF26G1, the protein encoded by the cloned cDNA, consists of 562 amino acids and shows high homology to a widely distributed family of β-glucosidases (BGA family). Cell-free homogenate of Escherichia coli expressing CSF26G1 cDNA showed β-glucosidase activity specific for cleavage of the C-26 glucosidic bond of furostanol glycosides

In Vitro Toxicity of Asparagus Saponins in Distinct Multidrug-Resistant Colon Cancer Cells

Colorectal cancer is the third most common cancer in the world. Many efforts have focused on finding natural molecules with potential chemo-preventive activity due to their low toxicity compared to synthetic drugs. However, comprehensive information on the bioactive fractions and components is still missing. In this study, we developed a method for the quantitative separation and isolation of saponins from asparagus genotypes consisting of an adsorption chromatography and subsequent liquid chromatographic separation on a reversed-phase column. The saponins isolated were tested for their cytotoxic activity against human colon cancer cell lines, which could develop cross-resistance to a wide variety of chemotherapeutic drugs. Our results showed that Huétor-Tájar asparagus saponins (HTSAP), mainly protodioscin and HTSAP-10 have higher cytotoxic activity than HTSAP-1, HTSAP-6, and HTSAP-8. This study links the potential anticancer effect of asparagus to specific saponins and unveils the triguero Huétor-Tájar asparagus as a nutraceutical particularly in colon cancer therapiesMinisterio de Economía y Competitividad JCI-2012-1308

Steroidal and pregnane glycosides from Ypsilandra thibetica

The whole plants of Ypsilandra thibetica have been analyzed as part of a systematic study on saponin constituents of medicinal plants. This has resulted in the isolation of two new bisdesmosidic furostanol saponins, named ypsilandroside P (1) and ypsilandroside Q (2), and one new pregnane glycoside, named ypsilandroside R (3), together with nine known steroidal glycosides. Their structures were elucidated on the basis of extensive spectroscopic analysis, including that of 2D NMR data, and the results of acidic hydrolysis. Ypsilandroside P (1) was cytotoxicity against two human tumor cell lines. [Image: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: Supplementary material is available for this article at 10.1007/s13659-011-0039-z and is accessible for authorized users

Steroidal Glycosides from the Seeds of Hyoscyamus niger L

The investigation of the steroidal glycosides of the seeds of Hyoscyamus niger L. led to the isolation of two new spirostane saponins (2, 6) together with seven known glycosides with either furostane or spirostane aglycones. On the basis of chemical and spectroscopic evidence, the structures of 2 and 6 were elucidated as (25 R)-5α-spirostan-3β-ol 3- O-β-D-glucopyranosyl-(1→3)-β-D-galactopyranoside (2) and (25 R)-5α-spirostan-3β-ol 3- O-β-D-glucopyranosyl-(1→3)-[β-D-glucopyranosyl-(1→2)]-β-D-galactopyranoside (6). The given compounds have been found for the first time in the genus Hyoscyamus

Phytochemical and Pharmacological Studies of the Genus Tacca: A Review

Tacca is an important genus comprising of approximately 15 species of the medicinal plants (Taccaceae). The plants are used in traditional medicine to relieve pains of the body and stomach, as an antidote for food  poisoning as well as for their analgesic, antipyretic and anti-inflammatory activities. Chemical studies have underlined more than 120 constituents have been isolated from Tacca, including steroidals, diarylheptanoids, phenolics,  flavonoids, sesquitepenoids, triterpenoids and starch. Steroidals and diarylheptanoids showed potent bioactivities, such as cytotoxic, microtubule-stabilizing, NF-kB activation and PPAR transcriptional and insecticidal activities. The starch from T. leontopetaloides and T. involucrata have high amylase content and showed potential use in food and drug system.Keywords: Tacca, Taccalonolides, Tacca starch, Microtubule-stabilizer, Anti-cance

Evaluation of saponin-rich extracts as natural alternative emulsifiers: A comparative study with pure Quillaja Bark saponin

Due to synthetic surfactants' environmental impact, their replacement by natural alternatives has gained relevance, with saponins emerging as sustainable approaches. In this work, three saponin-rich extracts from different sources (Tribulus terrestris (TT), Trigonella foenum-graecum (FG), and Ruscus aculeatus (RA)) were tested as emulsifiers, and their performance compared with Quillaja Bark saponin (PS). Characterisation comprised FTIR, solubility studies, CMC assays, and emulsifying properties (emulsifying capacity (EC) and foaming capacity (FC)). For all samples, solubility assays indicated high solubility in water and low in apolar solvents (e.g., n-hexane), compatible with their O/W emulsifier character. In general, the saponin content ruled extracts' performance (PS > TT > FG > RA). EC values (without pH adjustment) were found to be 82.5, 55.0, 47.5, 36.3%, respectively. When pH changed for 7 and 9, a shift in FG and RA order was observed. The pseudo-ternary diagrams, constructed to map emulsion's composition zones, indicate the formation of single-phase systems in the region of low oil and high extract content. Except for RA extract, gel samples were formed, which are interesting technological solutions for several applications. Among the studied samples, and in alternative to PS, TT extract showed the best performance.This work was financially supported by: Base Funding – UIDB/00690/2020 of CIMO – Centro de Investigação de Montanha – funded by national funds through FCT/MCTES (PIDDAC), Base Funding – UIDB/50020/2020 of the Associate Laboratory LSRE-LCM – funded by national funds through FCT/MCTES (PIDDAC), and project AIProcMat@ N2020 – NORTE-01-0145-FEDER 000006 supported by NORTE 2020 under the Portugal 2020 Partnership Agreement, through ERDF. National funding by FCT, Foundation for Science and Technology, through the individual research Grant 2020.05564. BD of Tatiana La Banca Schreiner. FCT, PI, through the institutional scientific employment program-contract for I.P. Fernandes contract through the celebration of program-contract foreseen in No. 4, 5 and 6 of article 23º of Decree-Law No. 57/2016, of 29th August, amended by Law No. 57/ 2017, of 19th July.info:eu-repo/semantics/publishedVersio

Antispasmodic saponins from bulbs of red onion, Allium cepa L. var. Tropea

A phytochemical analysis of the polar extract from the red bulbs of Allium cepa L. var. Tropea, typical of Calabria, a southern region of Italy, was performed extensively for the first time, leading to the isolation of four new furostanol saponins, named tropeoside A1/A2 (1a/1b) and tropeoside B1/B2 (3a/3b), along with the respective 22-O-methyl derivatives (2a/2b and 4a/4b), almost certainly extraction artifacts. High concentrations of ascalonicoside A1/A2 (5a/5b) and ascalonicoside B (6), previously isolated from Allium ascalonicum Hort., were also found. This is the first report of furostanol saponins in this A. cepa variety. The chemical structures of the new compounds were established through a combination of extensive nuclear magnetic resonance, mass spectrometry and chemical analyses. High concentrations of quercetin, quercetin 4(I)-glucoside, taxifolin, taxifolin 7-glucoside, and phenylalanine were also isolated. The new saponins were found to possess antispasmodic activity in the guinea pig isolated ileum; such an effect might contribute to explaining the traditional use of onion in the treatment of disturbances of the gastrointestinal tract