As part of our ongoing search for bioactive constituents of natural Korean medicinal resources, a bioassay-guided fractionation and chemical investigation of the MeOH extract of Raphanus sativus (Brassicaceae) seeds resulted in the isolation and identification of fifteen compounds, including a new phenolic compound. The structure of the new compound was determined by extensive spectroscopic analysis and the Mosher's method. One of the compounds has been recently reported as a synthetic product. Some compounds showed moderate antiproliferative activities against the tumor cell lines A549, SK-OV-3, SK-MEL-2, and HCT-15 with IC50 values in the range of 5.62 to 28.88 μM. Moreover, the anti-neuroinflammatory activities of the isolates were determined by measuring the nitric oxide (NO) levels in the medium using murine microglia BV-2 cells. With exception of one specific compound, all the others inhibited the lipopolysaccharide (LPS)-stimulated NO production (IC50 values < 200 μM).
An extended phytochemical investigation of the leaves of Hosta longipes identified the new flavonoid glycoside, kaempferol-3-O-β-D-glucopyranosyl-(1→2)-[6"'-O-acetyl-β-D-glucopyranoside]-7-O-β-D-glucopyranoside and five known flavonoid derivatives. The structures of two compounds were revealed by extensive NMR methods (¹H and 13C NMR, ¹H-¹H COSY, HMQC and HMBC) and chemical hydrolysis. NMR data of one of them are published for the first time. Bioactivities of six compounds revealed that five strongly inhibited the production of nitric oxide (NO) with IC50 values of 11.56-15.97 µm in lipopolysaccharide (LPS)-stimulated BV-2 cells without cell toxicity. Two compounds showed moderate induction of secretion of nerve growth factor (NGF) in C6 glioma cells (124.70 ± 7.71% and 117.02 ± 3.60%, respectively).
Investigação fitoquímica das folhas da Hosta longipes identificou um novo flavonóide glicosídeo, o caempferol-3-O-β-D-glucopiranosil-(1→2)-[6"'-O-acetil-β-D-glucopiranósido]-7-O-β-D-glucopiranósido, e mais cinco derivados flavonóides conhecidos. As estruturas de dois compostos foram reveladas por vários métodos de RMN (¹H e 13C RMN, ¹H-¹H COSY, HMQC HMBC) e hidrólise química. Dados de RMN de um deles são publicados pela primeira vez. As atividades biológicas de seis compostos revelaram que cinco inibiram fortemente a produção de óxido nítrico (NO), com valores de IC50 de 11,56-15,97 µm em células BV-2 estimuladas por lipopolissacarídeo (LPS), sem toxicidade celular. Dois compostos mostraram indução moderada da secreção no fator de crescimento do nervo (NGF) em linhagem de células C6 de glioma (124,70 ± 7,71% e 117,02 ± 3,60%, respectivamente).