Separation and Quantification of Selected Sapogenins Extracted from Nettle, White Dead-Nettle, Common Soapwort and Washnut.

Saponins are an important group of secondary metabolites naturally occurring in plants with important properties like: antibacterial, antiviral and antifungal. Moreover, they are widely used in the cosmetic industry and household chemistry. The sapogenins are saponin hydrolyses products, frequently used to facilitate saponin detection. In the present study, an improved methodology for isolation and separation of five sapogenins extracted from nettle (Urtica dioica L.), white dead-nettle (Lamium album L.), common soapwort (Saponaria officinalis L.) and washnut (Sapindus mukorossi Gaertn.) was developed using ultra-high-performance liquid chromatography with an evaporative light-scattering detector (UHPLC-ELSD). Based on quantitative analysis, the highest content of hederagenin (999.1 ± 6.3 µg/g) and oleanolic acid (386.5 ± 27.7 µg/g) was found in washnut extracts. Good recoveries (71% ± 6 up to 99% ± 8) were achieved for four investigated targets, while just 22.2% ± 0.5 was obtained for the fifth one. Moreover, hederagenin and oleanolic acid of whose highest amount was detected in washnut (999.1 ± 6.3 µg/g and 386.5 ± 27.7 µg/g, respectively) were subject to another approach. Consequently, liquid chromatography coupled mass spectrometry (LC/MS) with multiple reaction monitoring mode (MRM) was used as an additional technique for fast and simultaneous identification of the mentioned targets.

Spirostanol Sapogenins and Saponins from Convallaria majalis L. Structural Characterization by 2D NMR, Theoretical GIAO DFT Calculations and Molecular Modeling.

Two new spirostanol sapogenins (5ß-spirost-25(27)-en-1ß,2ß,3ß,5ß-tetrol 3 and its 25,27-dihydro derivative, (25S)-spirostan-1ß,2ß,3ß,5ß-tetrol 4) and four new saponins were isolated from the roots and rhizomes of Convallaria majalis L. together with known sapogenins (isolated from Liliaceae): 5ß-spirost-25(27)-en-1ß,3ß-diol 1, (25S)-spirostan-1ß,3ß-diol 2, 5ß-spirost-25(27)-en-1ß,3ß,4ß,5ß-tetrol 5, (25S)-spirostan-1ß,3ß,4ß,5ß-tetrol 6, 5ß-spirost-25(27)-en-1ß,2ß,3ß,4ß,5ß-pentol 7 and (25S)-spirostan-1ß,2ß,3ß,4ß,5ß-pentol 8. New steroidal saponins were found to be pentahydroxy 5-O-glycosides; 5ß-spirost-25(27)-en-1ß,2ß,3ß,4ß,5ß-pentol 5-O-ß-galactopyranoside 9, 5ß-spirost-25(27)-en-1ß,2ß,3ß,4ß,5ß-pentol 5-O-ß-arabinonoside 11, 5ß-(25S)-spirostan-1ß,2ß,3ß,4ß,5ß-pentol 5-O-galactoside 10 and 5ß-(25S)-spirostan-1ß,2ß,3ß,4ß,5ß-pentol 5-O-arabinoside 12 were isolated for the first time. The structures of those compounds were determined by NMR spectroscopy, including 2D COSY, HMBC, HSQC, NOESY, ROESY experiments, theoretical calculations of shielding constants by GIAO DFT, and mass spectrometry (FAB/LSI HR MS). An attempt was made to test biological activity, particularly as potential chemotherapeutic agents, using in silico methods. A set of 12 compounds was docked to the PDB structures of HER2 receptor and tubulin. The results indicated that diols have a higher affinity to the analyzed targets than tetrols and pentols. Two compounds (25S)-spirosten-1ß,3ß-diol 1 and 5ß-spirost-25(27)-en-1ß,2ß,3ß,4ß,5ß-pentol 5-O-galactoside 9 were selected for further evaluation of biological activity.

Anti-inflammatory steroidal sapogenins and a conjugated chalcone-stilbene from Dracaena usambarensis Engl.

Four new steroidal sapogenins, dracaenogenins CF (1-4), a new conjugated chalcone-stilbene, 3''-methoxycochinchinenene H (5) together with eight known compounds namely, (25S)-spirosta-1,4-dien-3-one (6), trans-resveratrol (7), 4,4'-dihydroxy-3'-methoxychalcone (8), N-trans-coumaroyltyramine (9), N-trans-p-coumaroyloctopamine (10), N-trans-feruloyloctopamine (11), 7-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-N2,N3-bis(4-hydroxyphenethyl)-6-methoxy-1,2-dihydronaphthalene-2,3-dicarboxamide (12) and grossamide (13) were isolated from the stems of Dracaena usambarensis Engl. from Kenya. It is important to note that compounds 12 and 13 are being reported from this genus for the first time. Structural elucidation of the isolated compounds was done using spectroscopic (NMR, UV, IR, optical rotation) and spectrometric (HRESIMS) techniques. The absolute and relative configurations of the isolated compounds were determined by employing single crystal X-ray crystallography analysis, NOESY correlations and coupling constants. The anti-inflammatory potencies of the isolated compounds were evaluated by measuring the levels of four cytokines (IL-1ß, IL-2, GM-CSF and TNF-α) in the supernatant media of human peripheral blood mononuclear cells (PBMCs) stimulated by lipopolysaccharide (LPS). At the tested concentration of 100 µM, the new conjugated chalcone-stilbene 5, the dihydrochalcone, 8 and the lignanamide, 13 were substantially more potent than the standard drug, ibuprofen, inhibiting the release of all the cytokines, IL-1ß, IL-2, GM-CSF and TNF-α from 0.06-58.04% compared to LPS control. These compounds should therefore be considered for development into anti-inflammatory drug candidates. Compound 7 significantly decreased the release of GM-CSF (6.11% of LPS control) and TNF-α (18.35% of LPS control). The cytokine TNF-α was sensitive to all the tested compounds 1-13.

Distribution of sapogenins in morphological Medicago sativa L. parts: Comparison of various extraction techniques.

Saponins in plant extracts were indirectly determined by estimation of the content of sapogenins. The first step of determination is extraction with high efficiency. One conventional extraction technique (maceration) and two modern ones (accelerated solvent extraction and supercritical fluid extraction) were compared. Methanol and ethanol were used as solvents or co-solvents. The results were supported by statistical analysis. Saponins were extracted from leaves, roots, and sprouts of Medicago sativa. Acid hydrolysis, purification, and determination by high-performance liquid chromatography with evaporative light scattering detector were used. The content of sapogenins was the highest in the roots. Smaller amounts of sapogenins were found in sprouts and the smallest ones in leaves. The main ingredient was medicagenic acid with mean concentration of 621.8 µg/g in roots, 456.7 µg/g in sprouts, and 471.3 µg/g in leaf extract. The highest content of sapogenins in extract was obtained after maceration with methanol; however, this method is nonselective in relation to biologically active compounds. Due to the possibility of using the obtained extracts with sapogenins in the cosmetic or pharmaceutical industry, the selection of extraction techniques and solvents is a very important aspect. Additionally, the chosen technique should be considered eco-friendly and consistent with the assumptions of "green chemistry."

Quantitative Proteomics Combined with Affinity MS Revealed the Molecular Mechanism of Ginsenoside Antitumor Effects.

Ginsenosides have previously been demonstrated to effectively inhibit cancer cell growth and survival in both animal models and cell lines. However, the specific ginsenoside component that is the active ingredient for cancer treatment through interaction with a target protein remains unknown. By an integrated quantitative proteomics approach via affinity mass spectrum (MS) technology, we deciphered the core structure of the ginsenoside active ingredient derived from crude extracts of ginsenosides and progressed toward identifying the target protein that mediates its anticancer activity. The Tandem Mass Tag (TMT) labeling quantitative proteomics technique acquired 55620 MS/MS spectra that identified 5499 proteins and 3045 modified proteins. Of these identified proteins, 224 differentially expressed proteins and modified proteins were significantly altered in nonsmall cell lung cancer cell lines. Bioinformatics tools for comprehensive analysis revealed that the Ras protein played a general regulatory role in many functional pathways and was probably the direct target protein of a compound in ginsenosides. Then, affinity MS screening based on the Ras protein identified 20(s)-protopanaxadiol, 20(s)-Ginsenoside Rh2, and 20(s)-Ginsenoside Rg3 had affinity with Ras protein under different conditions. In particular, 20(s)-protopanaxadiol, whose derivatives are the reported antitumor compounds 20(s)-Ginsenoside Rh2 and 20(s)-Ginsenoside Rg3 that have a higher affinity for Ras via a low KD of 1.22 µM and the mutation sites of G12 and G60, was demonstrated to play a core role in those interactions. Moreover, the molecular mechanism and bioactivity assessment results confirmed the identity of the chemical ligand that was directly acting on the GTP binding pocket of Ras and shown to be effective in cancer cell bioactivity profiles.

Transcriptome analysis of 1- and 3-year-old Panax notoginseng roots and functional characterization of saponin biosynthetic genes DS and CYP716A47-like.

MAIN CONCLUSION: Transcriptome analysis revealed high expression of saponin biosynthetic genes may account for highly accumulated saponins in 3-year-old Panax notoginseng roots and DS and CYP716A47 - like were functionally verified by transgenic tobacco. Panax notoginseng is a well-known traditional medical herb that contains bioactive compounds known as saponins. Three major dammarene-type triterpene saponins including R1, Rb1, and Rg1 were found to be highly accumulated in the roots of 3-year-old plants when compared to those of 1-year-old plants. However, the underlying cellular mechanism is poorly understood. In this study, transcriptome analysis revealed that most genes involved in saponin biosynthesis in P. notoginseng roots augmented during their growth periods. The analysis of the KEGG pathway indicated that the primary metabolism, cell growth, and differentiation were less active in the roots of 3-year-old plant; however, secondary metabolisms were enhanced, thus providing molecular evidence for the harvesting of P. notoginseng roots in the 3rd year of growth. Furthermore, the functional role of DS and CYP716A47-like, two of the candidate genes involved in saponin biosynthesis isolated from P. notoginseng, were verified via overexpression in cultivated tobacco. Approximately, 0.325 µg g-1 of dammarenediol-II and 0.320 µg g-1 of protopanaxadiol were recorded in the dry leaves of transgenic tobacco overexpressed with DS and both DS and CYP716A47-like, respectively. This study provides insights into the molecular mechanisms for saponin accumulation in P. notoginseng roots during its growth period and paves a promising way to produce dammarenediol-II and protopanaxadiol via transgenic techniques.

Cycloastragenol ameliorates experimental heart damage in rats by promoting myocardial autophagy via inhibition of AKT1-RPS6KB1 signaling.

Cycloastragenol, a naturally occurring compound in Astragali Radix, has been demonstrated to possess various pharmacological actions including anti-aging, anti-inflammation, anti-fibrosis, antibacterial, liver and endothelium protection. However, whether cycloastragenol ameliorates heart failure remains unclear. Isoproterenol administration to rats triggered classic cardiac damage, as demonstrated by objective parameters of cardiac dysfunction. The treatment of cycloastragenol improved deranged cardiac parameters in the isoproterenol-induced heart damage model in a dose-dependent manner. At the same time, cycloastragenol markedly ameliorated cardiac histological changes and down-regulated serum levels of various neuroendocrine factors including norepinephrine, aldosterone, brain natriuretic peptide, endothelin 1, angiotensin II and so on. Moreover, the expressions of matrix metalloproteinase-2 (MMP-2) and MMP-9 in rat heart were also inhibited by cycloastragenol. Mechanistically, augmenting autophagy of myocardial cells via the inhibition of AKT1-RPS6KB1 signaling contributed to the improvement of isoproterenol-induced rat heart failure by cycloastragenol. These results suggest that cycloastragenol ameliorates cardiac dysfunction and remodeling through promoting autophagy in myocardial cells and suppressing MMP-2 and MMP-9 expressions, indicating that it could be a drug candidate for patients with congestive heart failure.

Biotransformation of cyclocanthogenol by the endophytic fungus Alternaria eureka 1E1BL1.

The microbial transformation of cyclocanthogenol (CCG), Astragalus sp. originated sapogenin, by the endophytic fungus Alternaria eureka 1E1BL1 isolated from Astragalus angustifolius was investigated. Hydroxylation, oxidation, epoxidation, O-methylation, ring-expansion and methyl migration reactions were observed on the triterpenoid skeleton. As a result, eight metabolites were isolated and the structures of the previously undescribed compounds were established by 1-D, 2-D NMR and HR-MS analyses.

Bupleurum chinense Roots: a Bioactivity-Guided Approach toward Saponin-Type NF-κB Inhibitors.

The roots of Bupleurum chinense have a long history in traditional medicine to treat infectious diseases and inflammatory disorders. Two major compounds, saikosaponins A and D, were reported to exert potent anti-inflammatory activity by inhibiting NF-κB. In the present study, we isolated new saikosaponin analogues from the roots of B. chinese interfering with NF-κB activity in vitro. The methanol-soluble fraction of the dichloromethane extract of Radix Bupleuri was subjected to activity-guided isolation yielding 18 compounds, including triterpenoids and polyacetylenes. Their structures were determined by spectroscopic methods as saikogenin D (1), prosaikogenin D (2), saikosaponins B2 (3), W (4), B1 (5), Y (6), D (7), A (8), E (9), B4 (10), B3 (11), and T (12), saikodiyne A (13), D (14), E (15) and F (16), falcarindiol (17), and 1-linoleoyl-sn-glycero-3-phosphorylcholine (18). Among them, 4, 15, and 16 are new compounds, whereas 6, previously described as a semi-synthetic compound, is isolated from a natural source for the first time, and 13-17 are the first reports of polyacetylenes from this plant. Nine saponins/triterpenoids were tested for inhibition of NF-κB signaling in a cell-based NF-κB-dependent luciferase reporter gene model in vitro. Five of them (1, 2, 4, 6, and 8) showed strong (> 50%, at 30 µM) NF-κB inhibition, but also varying degrees of cytotoxicity, with compounds 1 and 4 (showing no significant cytotoxicity) presenting IC50 values of 14.0 µM and 14.1 µM in the cell-based assay, respectively.

Cross Interaction Between Ilyonectria mors-panacis Isolates Infecting Korean Ginseng and Ginseng Saponins in Correlation with Their Pathogenicity.

Ilyonectria mors-panacis belongs to I. radicicola species complex and causes root rot and replant failure of ginseng in Asia and North America. The aims of this work were to identify I. mors-panacis that infect Korean ginseng using molecular approaches and to investigate whether their aggressiveness depends on their ability to metabolize ginseng saponins (ginsenosides) by their ß-glucosidases, in comparison with other identified Ilyonectria species. Fourteen isolates were collected from culture collections or directly isolated from infected roots and mainly identified based on histone H3 (HIS H3) sequence. Among them, six isolates were identified as I. mors-panacis while others were identified as I. robusta and I. leucospermi. The pathogenicity tests confirmed that the isolates of I. mors-panacis were significantly more aggressive than I. robusta and I. leucospermi. The major ginsenosides in I. mors-panacis-infected roots were significantly reduced while significantly increased in those infected with other species. In vitro, the isolates were tested for their sensitivity and ability to metabolize the total major ginsenosides (Total MaG), protopanaxadiol-type major ginsenosides (PPD-type MaG), and protopanaxatriol-type major ginsenosides (PPT-type MaG). Unexpectedly, the growth rate and metabolic ability of I. mors-panacis isolates were significantly low on the three different ginsenoside fractions while those of I. robusta and I. leucospermi were significantly reduced on PPT-type MaG and Total MaG fractions and not affected on PPD-type MaG fraction. Our results indicate that major ginsenosides, especially PPT-type, have an antifungal effect and may intervene in ginseng defense during Ilyonectria species invasion, in particular the weak species. Also, the pathogenicity of I. mors-panacis may rely on its ability to reduce saponin content; however, whether this reduction is caused by detoxification or another method remains unclear.