Heveaflavone

Phytochem Anal. 2014 Mar-Apr;25(2):127-33.

Preparative isolation of six anti-tumour biflavonoids from Selaginella doederleinii Hieron by high-speed counter-current chromatography.[Pubmed: 24115163]

Biflavonoids are the primary constituents of Selaginella doederleinii Hieron, to which different bioactivities have been attributed, including anti-cancer, anti-inflammatory, anti-oxidant, anti-fungal and anti-virus activity. However, effective methods for separation of these compounds are not currently available. To develop a high performance and bioassay-guided method for preparative isolation of biflavonoids from S. doederleini via high-speed counter-current chromatography (HSCCC).
METHODS AND RESULTS:
The anti-proliferation effects of four fractions (70% ethanol, petroleum ether, dichloromethane and acetic ether extracts) of S. doederleinii on five human cancer cells were monitored. The dichloromethane and acetic ether extracts showed good cytotoxicities to the studied cancer cell lines, guiding the subsequent separation. Two solvent systems composed of n-hexane:ethyl acetate:methanol:water (1:2:1.5:1.5, v/v) and n-hexane:ethyl acetate:methanol:water (3:2:3:2, v/v) were developed for separation of the active fractions, respectively. Identification of the biflavonoids was performed by EI-MS(n) , (1) H- and (13) C-NMR. Under the optimised conditions, 12.6 mg amentoflavone (91.4%), 6.6 mg robustaflavone (90.4%), 7.5 mg 2'', 3''-dihydro-3', 3'''-biapigenin (98.2%) and 7.3 mg 3', 3'''-binaringenin (90.3%) from acetic ether extract (500 mg) and 6.3 mg Heveaflavone (93.5%) and 5.3 mg 7, 4', 7'', 4'''-tetra-O-methyl-amentoflavone (94.5%) from dichloromethane extract (200 mg) were obtained, respectively. The anti-proliferation effects of the six biflavonoids on the five human cancer cells were further verified.
CONCLUSIONS:
The study provides methodological references for simultaneously preparative isolation of several bioactive biflavones from the herbal family of Selaginella. It is the first report discovering 2'', 3''-dihydro-3', 3'''-biapigenin and 3', 3'''-binaringenin from this herb and describing their cytotoxicities to human cancer cell lines.

J Tradit Complement Med. 2012 Jul;2(3):220-6.

Naturally Occurring Cytotoxic [3'→8″]-Biflavonoids from Podocarpus nakaii.[Pubmed: 24716136]

METHODS AND RESULTS:
Bioassay-guided fractionation of the EtOH extract of the dried twigs of Podocarpus nakaii Hayata (Podocarpaceae), endemic plant in Taiwan has resulted in isolation of four [3'→8″]-biflavonoid derivatives, amenotoflavone (AF), podocarpusflavone-A (PF), II-4″,I-7-dimethoxyamentoflavone (DAF), and Heveaflavone (HF). Their structures were determined by physical and extensive spectroscopic analyses such as (1)H, (13)C, (1)H-(1)H COSY, HMQC, and HMBC, as well as comparison with literature values.
CONCLUSIONS:
Compounds PF and DAF showed significant inhibitions against DLD, KB, MCF-7, HEp-2 tumor cell lines (ED50 ca. 4.56-16.24 μg/mL) and induced cell apoptosis in MCF-7 via mainly sub-G1/S phase arrest. Furthermore, these compounds exhibited moderate Topoisomerase I inhibitory activity.

Int J Anal Chem. 2015;2015:849769.

Rapid Screening and Structural Characterization of Antioxidants from the Extract of Selaginella doederleinii Hieron with DPPH-UPLC-Q-TOF/MS Method.[Pubmed: 25792983]

METHODS AND RESULTS:
2,2-Diphenyl-1-picrylhydrazyl-ultra-high performance liquid chromatography-Q-time-of-flight mass spectrometry (DPPH-UPLC-Q-TOF/MS), as a rapid and efficient means, now was used for the first time to screen antioxidants from Selaginella doederleinii. The nine biflavone compounds were screened as potential antioxidants. The biflavones were structurally identified and divided into the three types, that is, amentoflavone-type, robustaflavone-type, and hinokiflavone-type biflavonoids. Among the compounds bilobetin (3) and putraflavone (8) were found from Selaginella doederleinii for the first time and others including amentoflavone (1), robustaflavone (2), 4'-methoxy robustaflavone (4), podocarpusflavone A (5), hinokiflavone (6), ginkgetin (7), and Heveaflavone (9) were identified previously in the plant. Moreover, nine biflavones possessed a good antioxidant activity via their DPPH free radical scavenging.
CONCLUSIONS:
It demonstrates that DPPH-UPLC-Q-TOF/MS exhibits strong capacity in separation and identification for small molecule. The method is suitable for rapid screening of antioxidants without the need for complicated systems and additional instruments.