Yoshihisa Asada

Flavonoid constituents from Glycyrrhiza glabra hairy root cultures.

An unusual biflavonoid named licoagrodin was isolated from the hairy root cultures of Glycyrrhiza glabra (Leguminosae) along with three prenylated retrochalcones, licoagrochalcones B, C, D, a prenylated aurone, licoagroaurone and four known prenylated flavonoids, licochalcone C, kanzonol Y, glyinflanin B and glycyrdione A. From the glycosidic fraction, a isoflavone glycoside, licoagroside A, and a maltol glycoside, licoagroside B were isolated together with four known isoflavone glycosides, two flavone C-glycosides, and three other glycosides. Their structures were elucidated on the basis of spectroscopic evidence.

Isoprenylated flavonoids from hairy root cultures of Glycyrrhiza glabra

Abstract Two new prenylated flavonoids, licoagrochalcone A and licoagrocarpin, were isolated from the hairy root cultures of Glycyrrhiza glabra along with eight known flavonoids. On the basis of spectroscopic evidence, the structures of the new compounds were elucidated as 3-prenyl-2′,4,4′-trihydroxychalcone and (6a R , 11a R )-4-prenyl-3-hydroxy-9-methoxypterocarpan, respectively.

Effects of nutrients on anthocyanin production in cultured cells of Aralia cordata

Abstract Good results for anthocyanin production in dark-grown calli of Aralia cordata Thunb. were obtained on the addition of sucrose as the carbon source and NH4+ and NO3− at a molar ratio of 1:4 (15 mM total nitrogen). Also, by supplementing NAA as auxin and kinetin as cytokinin, good results were obtained. The anthocyanin yield of high-selected callus cultures was 13.0% maximum dry weight on being cultured for three weeks in darkness. The major anthocyanin, about 70% of the total pigment in the cells, was identified as cyanidin 3-xylosylgalactoside.

Rosmarinic acid production by Coleus forskohliihairy root cultures

Coleus forskohlii hairy root cultures were found to produce forskolin and rosmarinic acid (RA) as the main metabolites. The growth and RA production by C. forskohlii hairy root cultures in various liquid media were examined. The hairy root cultures showed good growth in hormone-free Murashige and Skoog medium containing 3% (w/v) sucrose (MS medium), and Gamborg B5 medium containing 2% (w/v) sucrose (B5 medium). RA yield reached 4.0 mg (MS medium) and 4.4 mg (B5 medium) after 5 weeks of culture in a 100 ml flask containing 20 ml of each medium. Hairy root growth and RA were also investigated after treatment with various concentrations of yeast extract (YE), salicylic acid (SA) and methyl jasmonic acid (MJA). RA production in a 100 ml flask containing 20 ml B5 medium reached 5.4 mg (1.9 times more than control) with treatment of 0.01 or 1% (w/v) YE, 5.5 mg (2.0 times more than control) with treatment of 0.1 mM SA, and the maximum RA content with 9.5 mg per flask (3.4 times more than control) was obtained in the hairy roots treated with 0.1 mM MJA. These results suggest that MJA is an effective elicitor for production of RA in C. forskohlii hairy root cultures.

Carcinogenic activity of clivorine, a pyrrolizidine alkaloid isolated from Ligularia dentata

The carcinogenic activity of clivorine, a pyrrolizidine alkaloid isolated from Ligularia dentata, was studied in inbred ACI rats. Twelve animals in the experimental group received a 0.005% solution of clivorine in drinking water for 340 days and survived beyond 440 days after the beginning of the experiment. Of this group, 8 developed tumors in the liver; 2 developed hemangioendothelial sarcomas, and 6 developed neoplastic nodules. The hemangioendothelial sarcoma showed metastasis in the lung of one rat. No tumors were observed in the liver of the control animals.

Phytoremediation of bisphenol A by cultured suspension cells of Eucalyptus perriniana-regioselective hydroxylation and glycosylation

On biotransformation of bisphenol A by cultured suspension cells of Eucalyptus perriniana, three new biotransformation products, 2,2-bis(4-β-d-glucopyranosyloxyphenyl)propane, 2-(4-β-d-glucopyranosyloxy-3-hydroxyphenyl)-2-(4-β-d-glucopyranosyloxyphenyl)propane and 2-(4-β-d-glucopyranosyloxy-3-hydroxyphenyl)-2-(3-β-d-glucopyranosyloxy-4-hydroxyphenyl)propane were isolated after three days incubation. Cultured suspension cells of E. perriniana are capable of regioselective hydroxylation and glycosylation of bisphenol A.

Anthocyanin production in cultured cells of Aralia cordata Thunb

High anthocyanin-producing cell lines, which were grown in a dark or in a light-dark regime, were selected from callus cultures initiated from stem and leaf tissues of Aralia cordata Thunb. by small-cell-aggregate selection. To verify the optimum culture conditions for anthocyanin production, cells were tested by changing the various basal media, sucrose concentration and nitrogen source and concentration. Good growth was obtained in the dark on Linsmaier-Skoogs basal medium containing 1.0 mg l-1 2,4-d and 0.1 mg l-1 kinetin, 2% (w/v) sucrose and full strength of nitrogen concentration. However, the highest anthocyanin yield (10.3% dry wt) was obtained in the dark on B5 medium containing 1.0 mg l-1 2,4-d and 0.1 mg l-1 kinetin. Our results suggested that it has became feasible to find the most effective conditions for cell growth and anthocyanin production by optimizations of the nitrogen concentration and the ratio of NH4+ to NO3- in the medium.

Production of ginsenoside saponins by culturing ginseng (Panax ginseng) embryogenic tissues in bioreactors

SummaryGinseng (Panax ginseng) embryogenic tissues were cultured in three types of reactors and the ginsenoside productivities in these tissues were compared. As a result, the saponin productivity was the best when an airlift reactor was used, and more than twice of that when a paddle or internal turbine reactor was used. The tissues grew 9 fold during 42 days, and the ginsenoside pattern resembled that of ginseng leaves.

Stelleralides A–C, Novel Potent Anti-HIV Daphnane-Type Diterpenoids from Stellera chamaejasme L.

Three novel 1-alkyldaphnane-type diterpenes, stelleralides A-C (4-6), and five known compounds were isolated from the roots of Stellera chamaejasme L. The structures of 4-6 were elucidated by extensive spectroscopic analyses. Several isolated compounds showed potent anti-HIV activity. Compound 4 showed extremely potent anti-HIV activity (EC(90) 0.40 nM) with the lowest cytotoxicity (IC(50) 4.3 μM) and appears to be a promising compound for development into anti-AIDS clinical trial candidates.

Biosynthesis of the dimethylallyl moiety of glabrol in Glycyrrhiza glabra hairy root cultures via a non-mevalonate pathway.

Incorporation of [1-13C]glucose indicates that the biosynthesis of the hemiterpene moiety of glabrol, the main prenylated flavanone in the hairy root cultures of Glycyrrhiza glabra, proceeds via a glyceraldehyde/pyruvate non-mevalonate pathway.