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The Eucalyptus perriniana cultured cells are widely used to biotransform a variety of compounds. The glucosyltransferase activity of a crude protein extract of E. perriniana cultured cells was maximized when cell growth was in the pre-logarithmic to logarithmic phase. We cloned a cDNA encoding glucosyltransferase (EPGT) from E. perriniana cultured cells by RT-PCR using a degenerated primer and RACE-PCR. The cDNA contained an open reading frame encoding 467 amino acids with a calculated molecular mass of 51.6 kDa. The consensus sequence of the plant glucosyltransferases was included in the deduced amino acid sequence. The amino acid sequence of EPGT showed a high identity to glucosyltransferases from tobacco and petunia. The recombinant EPGT was expressed in Escherichia coli and its substrate specificity was examined using UDP-(U- 14 C) glucose. Cinnamic acid was the best sugar acceptor in the compounds tested.

Seven new biotransformation products, (1 R ,3 Z ,5 R , 8 S, 9 S)-caryophylla-3-ene-5,14-diol 14- O -β-gentiobioside, (1 R ,5 R ,8 S , 9 S)-caryophylla-4(15)-ene-5,14-diol 14- O -β-gentiobioside, (1 R ,4 R ,5 R ,8S,9S)-4,5-epoxycaryophyllane-14-ol 14- O -β-gentiobioside, (1 R ,4 R ,5 R ,8 R , 9 S)-4,5-epoxycaryophyllane-14-ol 14- O -β- d -glucopyranoside, (1 R ,4 R ,5 R ,8 S ,9 S ,11 R )-4,5-epoxycaryophyllane-12, 14-diol 12- O -β- d -glucopyranoside, (1 R ,4 S ,5 R ,8 S ,9 S )-4,8-epoxy- caryophyllane-5,14-diol 14- O -β- d -glucopyranoside and (1 R ,4 R ,5 R ,8 S ,9 S )-4,11,11-trimethyltricyclo[6.3.1.0 1,9 ] dodecane-5,8-diol 5- O -β- d -glucopyranoside, were isolated from a cell suspension culture of Eucalyptus perriniana following administration of caryophyllene oxide.

Four new biotransformation products, (1 R , 2 R , 4 S )-1,8-epoxy- p -menthan-2-yl O -β- d -glucopyranoside, (1 S , 3 R , 4 R )- and (1 R , 3 S , 4 S )-1,8-epoxy- p -menthan-3-yl O -β- d -glucopyranosides, and (1 S , 2 S , 4 R )-1,8-epoxy- p -menthan-2-yl O -β- d -glucopyranosyl-(1→6)-β- d -glucopyranoside, together with a known (1 S , 2 S , 4 R )-1,8-epoxy- p -menthan-2-yl O -β- d -glucopyranoside were isolated from a cell suspension culture of Eucalyptus perriniana following administration of 1,8-cineole.

Cinobufacini (huachansu), an aqueous extract from the skin of the toad Bufo bufo gargarizans Cantor, is a traditional Chinese medicinal preparation widely used in clinical cancer therapy in China. Here, we screened and identified active compounds of cinobufacini and investigated their apoptosis-inducing effect on HepG2 cells. Screening was performed using bioassay-guided isolation. The effects of different fractions on the proliferation of HepG2 cells were detected by the MTT assay. The extraction and isolation of active fractions were performed by chloroform extraction, silica column chromatography, preparative thin-layer chromatography and high-performance liquid chromatography. Nuclear magnetic resonance (NMR) imaging and electron ionization-mass spectrometry (EI-MS) were used to identify the structure of the active compounds. The extent of cell apoptosis was detected by Hoechst 33258 staining and flow cytometric analysis. Western blot analysis was used to detect the expression of the apoptosis-related proteins Bax and Bcl-2. Through bioassay-guided isolation, two compounds were isolated from cinobufacini. NMR and EI-MS data revealed these compounds to be resibufogenin and cinobufagin. Cinobufagin was determined to be the more efficient of the two in inhibiting the proliferation of HepG2 cells. Hoechst 33258 staining and flow cytometric analysis indicated that cinobufagin induced marked changes in apoptotic morphology and significantly increased the proportion of apoptotic cells in HepG2 cells. Western blot analysis showed that cinobufagin up-regulated Bax expression and down-regulated Bcl-2 expression. In conclusion, we screened and identified two anti-proliferation compounds of cinibufacini, resibufogenin and cinobufagin. The most effective compound, cinobufagin, inhibited cell proliferation by inducing the apoptosis of HepG2 cells. This was potentially triggered by regulation of the Bax/ Bcl-2 ratio.

Six new biotransformation products, (-)-borneol 2-O-beta-gentiobioside, (-)-borneol 2-O-beta-sophoroside, (-)-borneol 2',6'-di-O-(beta-D-glucopyranosyl)-beta-D-glucopyranoside, 6-exo-hydroxyborneol 2-O-beta-D-glucopyranoside, 4-hydroxyborneol 2-O-beta-D-glucopyranoside and 5-exo-hydroxyborneol 2-O-beta-gentiobioside, together with 5-exo-hydroxyborneol 2-O-beta-D-glucopyranoside, were isolated from jar fermentor cultures of Eucalyptus perriniana following administration of (-)-borneol.

A new biotransformation product, steviol 19-β-gentiobiosyl ester, together with steviol 19-β-glucopyranosyl ester and steviol-13- O -β-glucopyranoside 19-β-glucopyranosyl ester (rubusoside), was isolated from Eucalyptus perriniana jar fermentor culture following the administration of steviol. Only rubusoside was isolated as a biotransforination product of steviol from Coffea arabica cell suspension culture.

Two new biotransformation products, 28-hydroxy-18β-glycyrrhetinic acid 30-β- glucopyranosyl ester and 23,28-dihydroxy-18β-glycyrrhetinic acid 30-β-glucopyranosyl ester, together with 18β-glycyrrhetinic acid 30-β-glucopyranosyl ester were isolated from Eucalyptus perriniana cell suspension culture following administration of 18β- glycyrrhetinic acid. Only 18β-glycyrrhetinic acid 30-β-glucopyranosyl ester was isolated as a biotransformation product of 18β-glycyrrhetinic acid from Coffea arabica cell suspension culture.

Camellia sinensis cultured cells can produce purine alkaloids, caffeine and theobromine, but the productivity is lower than that of cultured coffee cells. Total amino acid content in C. sinensis cultured cells was higher than that in commercial green tea. The main amino acid in cultured cells was glutamine (40–70% total) and the presence of theanine was also confirmed. α-Spinasterol, α-spinasterol β- d -glucopyranoside and 22-dihydro-α-spinasterol β- d -glucopyranoside were also isolated from an ethyl acetate extract of C. sinensis cultured cells. A 1 -Barrigenol was isolated from the acid hydrolysate of the saponin fraction.

Three abietane diterpenoids were isolated from the suspension cultured cells of Torreya nucifera var. radicans along with four known abietane diterpenoids. Based on spectroscopic evidence, the structures of the three were elucidated as (3S,5R,10S)-7-oxo-12-methoxyabieta-8,11,13-triene-3,11-diol, (3S,5R,10S)-7-oxo-12-methoxyabieta-8,11,13-triene-3,11,14-triol and (5R,10S)-3-oxo-7R,12-dimethoxyabieta-8,11,13-trien-11-ol, respectively.

Cultured cells of Eucalyptus perriniana biotransformed (+)-menthol to its gentiobioside and triglucoside [2,6-di-O-(beta-D-glucopyranosyl)-beta-D-glucopyranoside]. The structures of these compounds were determined by means of NMR techniques.

Seven new biotransformation products were isolated from a jar fermentor culture of Eucalyptus perriniana following administration of (+)-camphor. The main product was (1S,4R,6S)-6-hydroxybornan-2-one 6-O-beta-D-glucopyranoside. The minor components were (1S,4R,6R)-6-hydroxybornan-2-one 6-O-beta-D-glucopyranoside, (1R,4S,6S)-6-hydroxybornan-2-one 6-O-beta-D-glucopyranoside, (1R,4R,5R)-5-hydroxybornan-2-one 5-O-beta-D-glucopyranoside, (1R,3R,4S)-3-hydroxybornan-2-one 3-O-beta-D-glucopyranoside, (1R,4R,7R)-8-hydroxybornan-2-one 8-O-beta-D-glucopyranoside and 2-(4-oxo-2,2,3-trimethylcyclopentyl)-ethyl-beta-D-glucopyranoside. All products were mono-glucosides and the oxygen function was introduced before glucosylation. Reduction of the ketone group of camphor was not observed.

Suspension cultures of Coffea arabica are able to convert phenylacetic acid and 2-( R , S )-phenylpropionic acid and its ethyl ester into their sucrose esters, β- d -fructofuranosyl 6- O -phenylacetyl-α- d -glucopyranoside and β- d -fructofuranosyl 6- O -[2-( R , S )-phenylpropionyl]-α- d -glucopyranoside, which are accumulated in the cells. The diastereomeric mixture of the sucrose ester of 2-( R , S )-phenylpropionic acid (R: S::1:1) was resolved by HPLC.

Eight triterpenes were isolated from the methanol extracts of Eucalyptus perriniana cultured cells as their methyl esters. The structures were elucidated by spectral data to be oleanolic acid, ursolic acid, maslinic acid, 2α-hydroxyursolic acid, hederagenin, 23-hydroxyursolic acid, arjunolic acid and asiatic acid.