Cytotoxic steroidal saponins from the roots and rhizomes of Maianthemum henryi.

Henryiosides F and G (1 and 2), two new steroidal saponins along with two known analogues (3 and 4) were obtained from the roots and rhizomes of Maianthemum henryi. Their structures were determined by physicochemical properties and spectroscopic methods including 1D, 2D-NMR, IR and HR-ESI-MS data analysis. Cytotoxic activity in human HepG2 and SW620 tumour cells were evaluated by the MTT method and all of the saponins exhibited cytotoxicity with IC50 values ranging from 15.33 µM to 57.85 µM.

Extraction, characterization and antioxidant activity evaluation of polysaccharides from Smilacina japonica.

Three polysaccharides of uniform molecular weight designated as SJP1-1, SJP2-1, and SJP3-1 from Smilacina japonica were studied in this paper. Respectively, their specific optical rotations were -45°, -75°, and -35°, their polysaccharide contents were 89.22%, 93.05%, and 59.83%, their relative average molecular weights were 1.87 × 105 Da, 1.04 × 105 Da, and 1.36 × 104 Da. Three polysaccharides were all composed mainly of the three monosaccharides mannose, glucose, and galactose, which together in SJP1-1, SJP2-1, and SJP3-1 respectively made up 96.34%, 98.23%, and 91.67% of the total polysaccharide. The polysaccharide structure was maintained mostly by ß-glucose (1 → 3), ß-glucose (1 → 4), α-mannose (1 → 3), and α-galactose (1 → 4) glycosidic linkages. Scanning electron microscopy showed that SJP1-1, SJP2-1, and SJP3-1 were smooth uniform microspheres with diameters of 10-20 µm that combined to form both uniformly dispersed particles and blocky structures. Finally, antioxidant assay showed that these polysaccharides all had a strong ability to scavenge ·OH and DPPH· radicals, with the effects of purified polysaccharides being greater than those of crude polysaccharides. This first report on the properties of these polysaccharides provides a basis for further studies to shed light on the medical properties of Smilacina japonica.

Metabolism, Excretion, and Tissue Distribution of Astilbin-Zein Nanoparticles in Rats.

The excretion, tissue distribution, and metabolic profile of astilbin in rat were studied by HPLC and UPLC-QTOF-MS. Astilbin underwent isomerization in the small intestine, and its four isomers were found in feces. Besides, taxifolin, the aglycone of astilbin, and its further metabolites by gut microbes through hydrogenation, dehydration, and ring-fission were found. The total feces excretion of astilbin was about 14.4% of administration. The forming of zein-caseinate nanoparticles can significantly delay and reduce the feces excretion of astilbin. Astilbin and its isomers were absorbed in their intact form. The main metabolites found in plasma and tissues were the methylated products. Astilbin was rapidly distributed in various tissues including brain and maintained relatively high concentration in heart. Compared with other tissues, significantly higher concentration and longer duration of astilbin were found in the gastrointestinal tract. Astilbin and its isomers were excreted in their intact and methylated form in urine.

Bioavailability Enhancement of Astilbin in Rats through Zein-Caseinate Nanoparticles.

Astilbin-encapsulated zein-caseinate nanoparticles were fabricated through the antisolvent method. The encapsulation and loading efficiency of astilbin in the nanoparticles were determined by high-performance liquid chromatography. The nanoparticles were characterized by particle size, ζ potential, redispersibility, scanning electron microscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy, and differential scanning calorimetry (DSC). Under the optimal formulation of astilbin, zein, and sodium caseinate with a mass ratio of 1:1:2, the size and ζ potential of the nanoparticles were 152.9 nm and -40.43 mV, respectively, while the encapsulation and loading efficiency of astilbin were 80.1 and 21.8%, respectively. The nanoparticles had good redispersibility in water without a particle size change after freeze drying. The nanoparticles showed a spherical shape with a smooth surface. XRD and DSC analyses showed that astilbin existed in amorphous form in the nanoparticles. The interactions between astilbin and the protein were found, and astilbin was encapsulated in nanoparticles rather than adsorbed. The diffusion of astilbin from nanoparticles was significantly faster than that of astilbin suspensions in both simulated gastric and intestinal fluids. Astilbin was relatively stable in simulated intestinal fluids, and the encapsulation in the nanoparticles showed a slight stability improvement effect. A pharmacokinetic study showed that the absolute bioavailability of astilbin was improved from 0.32 to 4.40% in rats through nanoparticle fabrication.

Two new steroidal saponins from Maianthemum henryi and their cytotoxic activity against human HepG2 tumor cells.

Two new steroidal saponins (1 and 2), along with four known ones (3 ∼ 6) were obtained from the roots and rhizomes of Maianthemum henryi, their structures were determined to be spirost-5, 25(27)-diene-lß, 3ß-diol 1-O-α-L-rhamnopyranosyl-(1 → 2)-4-O-acetyl-ß-D-fucopyranoside (1), (23S, 24S)-spirost-5, 25(27)-diene-lß, 3ß, 23, 24-tetrol 1-O-α-L-rhamnopyranosyl-(1 → 2)-4-O-acetyl-ß-D-fucopyranoside (2), spirost-5, 25(27)-diene-lß, 3ß-diol 1-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-fucopyranoside (3), spirost-5, 25(27)-diene-lß, 3ß-diol 1-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-xylopyranoside (4), Henryioside A (5)、Henryioside B (6), by physicochemical properties and spectroscopic methods. In addition, their cytotoxic activity against human HepG2 tumor cells was evaluated by MTT method and all of the compounds exhibited cytotoxicity with the cells.

Steroidal Constituents from Roots and Rhizomes of Smilacina japonica.

Four new steroidal constituents (1-4) along with two known steroidal glycosides (5 and 6) were isolated from the roots and rhizomes of Smilacina japonica. Analysis of their physicochemical properties and spectroscopic profiles identified the compounds as (25S)-5α-spirostan-9(11)-en-3ß, 17α-diol (1); (25S)-5α-spirostan-9(11)-en-3ß, 12ß-diol (2); (25S)-5α-spirostan-9(11)-en-3ß, 17α-diol-3-O-ß-d-glucopyranoside (3); (25S)-5α-spirostan-9(11)-en-3ß, 17α-diol-3-O-ß-d-glucopyranosyl-(1→2)-[ß-d-glucopyranosyl-(1→3)]-ß-d-galactopyranoside (4); japonicoside B (5); and japonicoside C (6). All six compounds showed cytotoxic activity against SMMC-7712, Bel-7402, A549, H460, and K562 human cancer cells.

Steroidal saponins from Smilacina japonica.

Three new steroidal saponins, japonicoside A (1), japonicoside B (2) and japonicoside C (3) were isolated from the dried rhizomes and roots of Smilacina japonica A. Gray. Their structures were elucidated as (25S)-5α-spirostan-9(11)-en-3ß-ol 3-O-ß-D-glucopyranosyl-(1→2)-[ß-D-xylopyranosyl-(1→3)]-ß-D-glucopyranosyl-(1→4)-ß-D-galactopyranoside (1), (25S)-5α-spirostan-9(11)-en-3ß,17α-diol 3-O-ß-D-glucopyranosyl-(1→2)-[ß-D-xylopyranosyl-(1→3)]-ß-D-glucopyranosyl-(1→4)-ß-D-galactopyranoside (2) and (25S)-5α-spirostan-9(11)-en-3ß,17α,24α-triol 3-O-ß-D-glucopyranosyl-(1→2)-[ß-D-xylopyranosyl-(1→3)]-ß-D-glucopyranosyl-(1→4)-ß-D-galactopyranoside (3) on the basis of chemical methods and detailed spectroscopic analysis, including 1D, 2D NMR and HR-ESI-MS. The cytotoxicity of isolated compounds was evaluated in vitro for cytotoxic properties against human hepatocellular carcinoma cells (SMMC-7221) and human colorectal adenocarcinoma cells (DLD-1), respectively.

[Furosteroidal saponin from Smilacina japonica].

Smilacina japonica is a perennial herb, belonging to Smilacina genus of Liliaceae. A new furosteroidal saponin (1) was isolated and purified from the ethanol extract of the rhizome of S. japonica by various column chromatography. Its structure was established as 26-O-beta-D-glucopyranosyl-(25R)-furost-5-en-3beta, 12, 17alpha, 22xi, 26-pentol-12-O-acetyle-3-O-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranoside by physical and chemical properties and IR, MS, 1D, 2D NMR techniques. It showed strong cytotoxicity against the SPC-A-1 cancer cell lines.

Steroidal saponins and cytoxicity of the wild edible vegetable-Smilacina atropurpurea.

Four new steroidal saponins, smilacinoside A (1), B (2), C (3), and D (4), together with three known saponins, funkioside D (5), aspidistrin (6) and 26-O-beta-d-glucopyranosyl-22-methoxyl-(25R)-furost-5-en-3beta,26-diol 3-O-beta-d-glucopyranosyl-(1-->2)-beta-d-glucopyranosyl-(1-->4)-beta-d-galactopyranoside (7) were isolated from the dried tender aerial parts of Smilacina atropurpurea (Franch.) Wang et Tang. The structures of new compounds were elucidated as diosgenin 3-O-alpha-l-rhamnopyranosyl-(1-->2)-O-beta-d-galactopyranoside (1), diosgenin 3-O-alpha-l-rhamnopyranosyl-(1-->3)-[6-O-palmitoxyl]-O-beta-d-galactopyranoside (2), 26-O-beta-d-glucopyranosyl-(25R)-furost-5-en-3beta,22xi,26-triol 3-O-alpha-l-rhamnopyranosyl-(1-->2)}-beta-d-galactopyranoside (3) and 26-O-beta-d-glucopyranosyl-22-methoxyl-(25R)-furost-5-en-3beta,26-diol 3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-d-galactopyranoside (4) on the basis of chemical methods and detailed spectroscopic analysis, including 1D and 2D NMR techniques and single-crystal X-ray diffraction, respectively. Six of these compounds and MeOH extract were tested for their in vitro cytotoxicity toward K562 human tumor cells by an improved MTT method. Smilacinoside A, funkioside D and aspidistrin exhibited significant in vitro cytotoxicity against K562 with IC(50) values of 1.09, 2.93 and 0.47microg/mL, respectively.

3,4-dihydroxybenzoic acid from Smilacis chinae rhizome protects amyloid beta protein (25-35)-induced neurotoxicity in cultured rat cortical neurons.

The neuroprotective effect of 3,4-dihydroxybenzoic acid (3,4-DHBA) isolated from Smilacis chinae rhizome against Abeta (25-35)-induced neurotoxicity on cultured rat cortical neurons was found in this study. The protective effect of 3,4-DHBA against Abeta (25-35)-induced neuronal cell death was investigated by measuring cell viability via a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. 3,4-DHBA (1 and 10 microM) concentration-dependently inhibited 10 microM Abeta (25-35)-induced neuronal apoptotic death. 3,4-DHBA (1 and 10 microM) inhibited 10 microM Abeta (25-35)-induced elevation of cytosolic Ca(2+) concentration ([Ca(2+)](c)), which was measured by a fluorescent dye, Fluo-4 AM. 3,4-DHBA also inhibited glutamate release into medium, reactive oxygen species (ROS) generation, and caspase-3 activation, which were induced by 10 microM Abeta (25-35). These results suggest that 3,4-DHBA prevents Abeta (25-35)-induced neuronal cell damage by interfering with the increase of [Ca(2+)](c), and then by inhibiting glutamate release, generation of ROS and caspase-3 activity.

Atropurosides A-G, new steroidal saponins from Smilacina atropurpurea.

Atropurosides A-G (1-7), seven new steroidal saponins, which possess new polyhydroxylated aglycones, were isolated from the rhizomes of Smilacina atropurpurea (Convallariaceae), together with a known saponin, dioscin (8). Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1D and 2D NMR techniques and chemical methods. Antifungal testing of the eight compounds indicated that atropurosides B (2) and F (6) were fungicidal against Candida albicans, Candida glabrata, Cryptococcus neoformans, and Aspergillus fumigatus with minimum fungicidal concentrations (MFCs) < or = 20 microg/ml, while dioscin (8) was selectively active against C. albicans and C. glabrata (MFC < or = 5.0 microg/ml). Furthermore, the antifungal saponins 2, 6, and 8 were evaluated for their in vitro cytotoxicities in a panel of human cancer cell lines (SK-MEL, KB, BT-549, SK-OV-3, and HepG2) and non-cancerous Vero cells. All showed moderate cytotoxicities. It appears that the antifungal activity of these steroidal saponins correlates with their cytotoxicity against mammalian cells.