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Five new steroidal saponins ( 1 – 5 ) were isolated from the fermentation broth of total furostanol glycosides from tubers of Dioscorea zingiberensis C.H. Wright incubated with a fungal, Absidia coerulea AS 3.3389, along with known saponins, zingiberensis new saponin ( 6 ), deltonin ( 7 ), prosapogenin A of dioscin ( 8 ), and protobioside ( 9 ), and their structures were established by NMR spectroscopy and mass spectrometry as well as by comparison with previously reported spectral data in the literatures. The induced effects in vitro on rat platelet aggregation of all compounds were evaluated.

In this study seven strains of the genus Arthrobacter were screened by biotransformation to discover glycosylating patterns on steroid saponins. A strain of Arthrobacter nitroguajacolicus (CPCC 203516) was found to have the ability of fructosylation. Crude enzyme of the strain was extracted for the further study of conversion characteristics and patterns. Sucrose was used as a non-activated sugar donor, and fifteen steroidal saponins were involved. Nine furostan saponins of the substrates were converted, and ten products were isolated and identified. Based on the HR-ESI-MS, 1D, and 2D NMR spectral data, one fructosyl was added to furostan saponins at C6-OH of 26-O-β- d -glucopyranosyl by A. nitroguajacolicus for all nine products. One product was distinguished by an additional fructosyl at the position of C6-OH on the first added fructosyl. Spirostan saponins of the substrates could not be converted. Steroidal saponins embracing a fructosyl are quite rare according to other reports based on similar studies. This study successfully converted furostan saponins into new compounds.

Three new oleanane-type triterpenoid saponins named celosins H (1), I (2), and J (3) were isolated from the seeds of Celosia argentea L. Their structures were characterized as 3-O-β-d-xylopyranosyl-(1 → 3)-β-d-glucuronopyranosyl-polygalagenin 28-O-β-d-glucopyranosyl ester, 3-O-β-d-glucuronopyranosyl-medicagenic acid 28-O-β-d-xylcopyranosyl-(1 → 4)-α-l-rhamnopyranosyl-(1 → 2)-β-d-fucopyranosyl ester, and 3-O-β-d-glucuronopyranosyl-medicagenic acid 28-O-α-l-arabinopyranosyl-(1 → 3)-[β-d-xylcopyranosyl-(1 → 4)]-α-l-rhamnopyranosyl-(1 → 2)-β-d-fucopyranosyl ester by NMR, MS, and chemical evidences, respectively. In our opinion, celosins H–J could be used as chemical markers for the quality control of C. argentea seeds.

Twelve flavonoid glycosides were involved in the biotransformation of the glycosyl moieties by Curvularia lunata 3.4381, and the products were analyzed by UPLC/PDA-Q-TOF-MS(E). Curvularia lunata displayed hydrolyzing activities on the terminal Rha or Glc units of some flavonoid glycosides. Terminal Rha with a 1 → 2 linkage of isorhamnetin-3-O-neohesperidoside and typhaneoside could be hydrolyzed by Curvularia lunata, but terminal Rha with a 1 → 6 linkage of rutin, typhaneoside, and quercetin-3-O-apiosyl-(1 → 2)-[rhamnosyl-(1 → 6)]-glucoside could not be hydrolyzed. Curvularia lunata could also hydrolyze the Glc of icariin, floramanoside B, and naringin. This is the first report of the hydrolysis of glycosyl units of flavonoid glycosides by Curvularia lunata. A new way to convert naringin to naringenin was found in this research.

Two new kaurene diterpenoid glycosides, named Graecumoside A (1) and B (2), were isolated from fenugreek seeds, along with three known flavonoid-C-glycosides, isoorientin (3), isovitexin (4) and vitexin (5). By combined analyses of 1D- and 2D-NMR, and MS spectroscopy, the structures of two new compounds were elucidated as 3-O-β- D-glucopyranosyl kaur-5, 16-dien-3β, 6, 13β-trihydroxy-7-oxo-18-oic acid methyl ester and 3-O-β-neohesperidosyl kaur-5, 16-dien-3β, 6, 13β-trihydroxy-7-oxo-18-oic acid methyl ester, respectively. The kaurene diterpenoid glycosides were first isolated and identified from fenugreek seeds.

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.

Nine spirostanol saponins (1-9) and seven mixtures of 25 R and 25 S spirostanol saponin isomers (10-16) were obtained from the seeds of Trigonella foenum-graecum after enzymatic hydrolysis of the furostanol saponin fraction by β-glucosidase. Their structures were determined by NMR and MS spectroscopy. Among them, 1- 4, 6, 8, and 9 were new compounds and five, 11B, 12A, 13B, 14A, and 14B, were new structures observed from seven mixtures. In addition, the inhibitory effects of all saponins on rat platelet aggregation were evaluated.

Two new furostanol saponins, together with two known steroidal saponins, were isolated from the seeds of Trigonella foenum-graecum L. The structures of the new compounds were determined by detailed analysis of 1D NMR, 2D NMR, MS spectra and chemical evidences as 26-O-β-d-glucopyranosyl-(25S)-5-en-furost-3β,22α,26-triol 3-O-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl-(1 → 3)-β-d-glucopyranosyl-(1 → 4)]-β-d-glucopyranoside (1) and 26-O-β-d-glucopyranosyl-(25R)-5-en-furost-3β,22α,26-triol 3-O-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 6)]-β-d-glucopyranosyl-(1 → 3)-β-d-glucopyranosyl-(1 → 4)]-β-d-glucopyranoside (2).

A new furostanol saponin, sisalasaponin C (1), and a new spirostanol saponin, sisalasaponin D (2), were isolated from the fresh leaves of Agave sisalana, along with three other known steroidal saponins and two stilbenes. Their structures were identified as (3β,5α,6α,22α,25R)-3,26-bis[(β-D-glucopyrano- syl)oxy]-22-hydroxyfurostan-6-yl β-D-glucopyranoside (1), (3β,5α,25R)-12-oxospirostan-3-yl 6-deoxy-α-L-mannopyranosyl-(14)-β-D-glucopyranosyl-(13)-[β-D-xylopyranosyl-(13)-β-D-glucopyranosyl-(12)]-β-D-glucopyranosyl-(14)-β-D-galactopyranoside (2), (3β,5α,6α,22α,25R)-22-methoxyfurostane-3,6,26-triyl tris-β-D-glucopyranoside, cantalasaponin-1, polianthoside D, (E)- and (Z)-2,3,4′,5-tetrahydroxystilbene 2-O-β-D-glucopyranosides. The last three known compounds were isolated from the fresh leaves of Agavaceae for the first time. The structures of the new compounds were elucidated by detailed spectroscopic analysis, including 1D- and 2D-NMR experiments, and chemical techniques.

Two new spirostanol saponins, kingianoside I (1) and kingianoside K (2), corresponding to (3β,23S,25R)-23-hydroxy-12-oxospirost-5-en-3-yl 4-O-β-D-glucopyranosyl-β-D-galactopyranoside (1) and (3β,25R)-7-oxospirost-5-en-3-yl α-L-arabinofuranosyl-(14)-[6-deoxy-α-L-mannopyranosyl-(12)]-β-D-glucopyranoside (2), along with 13 known compounds, daucosterol, (25R)-kingianoside G, (25RS)-kingianoside A, pratioside D1, (25RS)-pratioside D1, (25S)-kingianoside C, kingianoside C, ginsenoside Rb1, saponins Tb and Pb, dioscin, gracillin, and saponin Pa, were isolated from the processed rhizomes of Polygonatum kingianum. The structures of the new compounds were elucidated by detailed spectroscopic analyses, including 1D- and 2D-NMR techniques, and chemical methods. Compound 2 contains a novel unusual spirostanol saponin aglycone. Ginsenoside Rb1 and saponin Tb were isolated for the first time from the genus Polygonatum. The 13 known compounds were detected for the first time in the processed Polygonatum kingianum.

Two new steroidal saponins, timosaponin X (1) and timosaponin Y (2), and one new pregnane glycoside, timopregnane B (3), were isolated from the rhizomes of Anemarrhena asphodeloides, as well as three known compounds 25S-timosaponin BII (4), protodesgalactotigonin (5), and timosaponin BII-a (6) isolated from this plant for the first time. By the detailed analysis of 1D, 2D NMR, MS spectra, and chemical evidences, the structures of new compounds were elucidated as 26-O-β-d-glucopyranosyl-(25S)-5β-22-methoxy-furost-3β,26-diol 3-O-β-d-glucopyranosyl-(1 → 2)-α-l-arabinopyranoside (1), 5β-pseudo-spirost-3β,15α,23α-triol 3-O-β-d-glucopyranosyl-(1 → 2)-β-d-galactopyranoside (2), (5β,17α)-Δ((16)(17))-20-one-pregn-2β,3β-diol 3-O-β-d-glucopyranosyl-(1 → 2)-β-d-galactopyranoside (3).

For the first time, a systematic phytochemical study was performed on the roots of Marsdenia tenacissima. Finally, sixteen new polyoxypregnane glycosides, marstenacissides A1-A7 (1-7) and marstenacissides B1-B9 (8-16), were isolated from M. tenacissima roots. The structures of these new compounds were established by various spectroscopic techniques, including 1D and 2D NMR spectroscopy and mass spectrometry.

Two new furostanol saponins (1 and 2), along with one known saponin (3), were obtained from the rhizomes of Aspidistra typica Baill. Their structures were elucidated as (25R)-26-O-β-d-glucopyranosyl-furost-5-ene-12-one-3β,22α,26-triol-3-O-β-d-glucopyranosyl-(1 → 2)-[β-d-xylopyranosyl-(1 → 3)]-β-d-glucopyranosyl-(1 → 4)-β-d-galactopyranoside (1, typaspidoside A), (25S)-26-O-β-d-glucopyranosyl-furost-5-ene-12-one-3β,22α,26-triol-3-O-β-d-glucopyranosyl-(1 → 2)-[β-d-xylopyranosyl-(1 → 3)]-β-d-glucopyranosyl-(1 → 4)-β-d-galactopyranoside (2, 25S-typaspidoside A), and timosaponin H1 (3), based on the integrative spectroscopic analysis of 1D- and 2D-NMR experiments, ESI-MS data and chemical evidence. The investigation on the chemical components of this plant is reported for the first time.

Phytochemical investigation of the fresh tubers of Ophiopogon japonicus led to the isolation of two new furostanol saponins (1 and 2) together with two known steroidal saponins (3 and 4). Comprehensive spectroscopic analysis allowed the chemical structures of two new compounds to be elucidated as (25R)-26-O-[β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl]-5-ene-furost-1β,3β,22α,26-tetraol-3-O-α-l-rhamnopyranosyl-(1 → 2)-[β-d-xylopyranosyl-(1 → 4)]-β-d-glucopyranoside (1, ophiopogonin P) and (25R)-26-O-[β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl]-5-ene-furost-1β,3β,22α,26-tetraol-3-O-α-l-rhamnopyranosyl-(1 → 2)-[β-d-xylopyranosyl-(1 → 4)]-β-d-glucopyranoside (2, ophiopogonin Q). Furostanol saponins with the disaccharide chain linked at C-26 hydroxy group of the aglycone have been rarely reported from natural sources.

Three new steroidal saponins, parisyunnanosides G-I (1-3), one new C(21) steroidal glycoside, parisyunnanoside J (4), and three known compounds, padelaoside B (5), pinnatasterone (6), and 20-hydroxyecdyson (7), were isolated from the rhizomes of Paris polyphylla Smith var. yunnanensis. Compounds 1 and 3 have unique trisdesmoside structures that include a C-21 β-d-galactopyranose moiety. All compounds were evaluated for their cytotoxicity against human CCRF leukemia cells.

Five new steroidal glycosides, timosaponin J ( 1), timosaponin K ( 2), (25 S)-karatavioside C ( 5), timosaponin L ( 6), and (25 S)-officinalisnin-I ( 8), together with eight known steroidal saponins, timosaponin E (1) ( 3), purpureagitosid ( 4), timosaponin BII ( 7), timosaponin B III ( 9), anemarrhenasaponin I ( 10), anemarrhenasaponin III ( 11), anemarrhenasaponin A (2) ( 12), and timosaponin A III ( 13), were isolated from the rhizomes of Anemarrhena asphodeloides. Their structures were elucidated on the basis of spectroscopic and chemical evidence. The aglycones of compounds 1 and 2 are new aglycones. Compounds 1- 13 were evaluated for their platelet aggregation activities, and compound 13 exhibited the strongest inhibitory effect on adenosine diphosphate (ADP)-induced platelet aggregation.