Natural Products from Selaginella sinensis

Sinensioside A, a new sesquilignan glycoside from Selaginella sinensis.[Pubmed: 24636067]

To investigate the chemical constituents of Selaginella sinensis (Desv.) Spring.

Target-guided isolation and purification of antioxidants from Selaginella sinensis by offline coupling of DPPH-HPLC and HSCCC experiments.[Pubmed: 21183411]

Selaginella sinensis (Selaginellaceae) is used extensively in traditional Chinese medicine (TCM) for the treatment of many kinds of chronic diseases. In this study, fractionation of the methanol extract of S. sinensis by different polarity solvents indicated the ethyl acetate fraction exhibited an potent 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging activity with the IC(50) value of 44.9 μM. In order to evaluate the scientific basis, antioxidant peaks were firstly screened using DPPH spiking test through high performance liquid chromatography (DPPH-HPLC). Under the target-guidance of DPPH-HPLC experiment, two flavonoids and six biflavonoids, quercetin (1), apigenin (2), amentoflavone (3), robustaflavone (4), 2,3-dihydroamentaflavone (5), hinokiflavone (6), 4'-O-methyl-robustaflavone (7) and ginkgetin (8) were separated by high-speed counter-current chromatography (HSCCC) method using n-hexane-ethyl acetate-methanol-water (8:8:9:7) as the solvent system with purities 98.2%, 97.6%, 99.4%, 92.3%, 98.5%, 98.9% and 99.6%, respectively. The structures were identified by electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) analysis. Antioxidant activity of eight isolated compounds was assessed by the radical scavenging effect on DPPH radical, compound 1 showed strongest antioxidant activities with IC(50) values of 3.2 μM, while compounds 2-8 showed weak antioxidant activities. This is the first report on simultaneous separation of eight antioxidant compounds from S. sinensis by HSCCC, moreover, apigenin and 4'-O-methyl-robustaflavone were first identified from this plant. Results of the present study indicated that the combinative method using DPPH-HPLC and HSCCC could be widely applied for rapid screening and isolating of antioxidants from complex TCM extract.

Two new secolignans from Selaginella sinensis (Desv.) Spring.[Pubmed: 20183303]

Two new secolignans, 3,4-trans-3-hydroxymethyl-4-[bis(4-hydroxyphenyl)methyl]butyrolactone (1) and 2,3-trans-3,4-trans-2-methoxy-3-hydroxymethyl-4-[bis(4-hydroxyphenyl)methyl]tetrahydrofuran (2), together with six known compounds, were isolated from the whole grass of Selaginella sinensis (Desv.) Spring. Their structures were elucidated by NMR and MS experiments.

A new unusual natural pigment from Selaginella sinensis and its noticeable physicochemical properties.[Pubmed: 17439180]

A new unusual pigment with a novel carbon framework named selaginellin (1) was isolated from the acetone extract of Selaginella sinensis, and its methoxy derivative (1a) was synthesized. Both selaginellin 1 and 1a are racemic compounds. The structure of selaginellin 1 was established as (R,S)-4-[(4'-hydroxy-4-(hydroxymethyl)-3-((4-hydroxyphenyl)ethynyl)biphenyl-2-yl)(4-hydroxyphenyl)methylene]-2,5-cyclohexadien-1-one and 1a as (R,S)-4-[(4'-methoxy-4-(methoxymethyl)-3-((4-methoxyphenyl)ethynyl)biphenyl-2-yl)(4-methoxyphenyl)methylene]-2,5-cyclohexadien-1-one by the analysis of one- and two-dimensional NMR data, HR-ESIMS, EI-MS, IR, UV, CD, and single-crystal X-ray experiments, and the mechanism of their color change according to different pH values and fluorescent properties was studied.

A new glucoside from Selaginella sinensis.[Pubmed: 16931428]

A new glucoside, selaginoside (1), together with two known compounds, hinokiflavone (2) and 2,3-dihydroamentoflavone (3), were isolated from the whole plants of Selaginella sinensis. Their structures were elucidated by means of spectroscopic methods.

Antiviral amentoflavone from Selaginella sinensis.[Pubmed: 11256492]

Amentoflavone and three other flavonoids were isolated from the ethanol extract of Selaginella sinensis. Amentoflavone showed potent antiviral activity against respiratory syncytial virus (RSV), with an IC50 of 5.5 microg/ml. The contents of amentoflavone in nine species of Selaginella were determined by reversed-phase HPLC. S. sinensis showed a higher content of 1.13%.