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The effects of polymerization concentrations and elementary reaction rates on the network structure and mechanical properties of gels synthesized by free radical copolymerization of monomers and cross-linkers are studied by a coarse-grained molecular dynamics simulation. The shear modulus, the number of elastically effective chains, and the number of trapped entanglements are calculated with varying the concentrations. The results reveal that the experimentally reported high cross-linking efficiency of the gels formed at high monomer concentrations and low cross-linker concentrations is due to the large number of trapped entanglements. The molecular mechanisms of changes in the network structure due to changes in the concentrations are elucidated by analyzing the detailed structure of network strands connecting adjacent cross-linking points. The results with systematically varying the elementary reaction rates indicate that the decrease in the propagation rate suppresses the formation of cyclic structures and reduces the influence of the trapped entanglements, i.e., improves the structural uniformity of the gels.

The effects of the primary structure of multifunctional reactive polymers on the network structure and the mechanical properties of gels formed by crosslinking the reactive polymers with crosslinkers are studied by a coarse-grained molecular dynamics simulation. When functional groups are randomly arranged on the polymers, the network structure, such as the number densities of elastically effective chains and entanglements, and the mechanical properties depend on the number average molecular weight of the polymers; however, these properties are almost independent of the molecular weight distribution and the functional group number distribution of the polymers. The control of the arrangement of functional groups on the polymers improves the uniformity and the mechanical properties. By changing the arrangement from a random one to a periodic one, the number of elastically effective chains and the shear modulus increase, and the occurrence of entanglement is suppressed. The detailed analysis of the network structure reveals that the improvement of the mechanical properties is mainly due to the reduction of intramolecular crosslinking.

We study the structures and the mechanical properties of nanocomposite networks consisting of disk-shaped particles and polymers by a coarse-grained molecular dynamics simulation. The disk-shaped particles and the polymers form tightly cross-linked network structures by the polymer adsorption on the disk-shaped particles and show high mechanical strength. We confirm the significance of the high polymerization degree for the large fracture elongations. Under the uniaxial elongation, at low elongation ratios, the networks maintain the cross-linked structures and indicate the sharp increase of the stress with the elongation. At large elongation ratios, the number of bridge chains decreases by the peeling of the adsorbed polymers from the disk-shaped particles. The decline of the bridge chains suppresses the increment of the stress. The orientation of the disk-shaped particles saturates prior to that of the polymers because of the slow orientation of the non-bridge chains. These results are consistent with reported experimental results.

We study the inclusion complex formation of cyclodextrins and a single polymer chain by a grand canonical Monte Carlo simulation and by a statistical-mechanical theory. The filling ratio of the polymer chain by threaded cyclodextrins is calculated and shows good agreement with reported experimental results. The adsorption isotherm of the filling ratio is also derived by the statistical-mechanical theory. We confirm the significance of hydrogen bonds between cyclodextrins for the inclusion complex formation. When hydrogen bonds can be formed between cyclodextrins, the filling ratio drastically increases at a certain concentration of the cyclodextrins, and inclusion complexes are formed. However, inclusion complexes are rarely formed without hydrogen bonds. We also find the expansion of size of the polymer chain with the development of one-dimensional aggregates constructed by threaded cyclodextrins along the polymer chain.

The structures and the mechanical properties of networks formed by end-linking of two types of tetra-arm star polymers are studied by a coarse-grained molecular dynamics simulation. The formation efficiency of elastically effective chains is improved by increasing the length of the arms and the volume fraction of the star polymers at the preparation stage. When the uniaxial elongation is applied to the networks in the as-prepared state, the shear modulus is proportional to the number density of the elastically effective chains and indicates an intermediate value between the phantom and affine network models. In the equilibrium swollen state, the shear moduli of the networks prepared at high volume fractions are significantly enhanced by trapped entanglements. The networks formed from the tetra-arm star polymers show higher number densities of the elastically effective chains than networks consisting of telechelic functional polymers and cross-linkers.

The influence of added surfactants on physical properties of associating polymer solutions was examined by a new statistical-mechanical theory of associating polymer solutions with multiple junctions and by computer simulation. The sol-gel transition line, the spinodal line, and the number of elastically effective chains in the mixed networks were calculated as functions of the concentration of added surfactants. All of them exhibited nonmonotonic behavior as a result of the following two competing mechanisms. One was the formation of new mixed micelles by binding surfactants onto the polymer associative groups. These micelles serve as crosslink junctions and promote gelation. The other was the replacement of polymer associative groups in the already formed network junctions by added surfactants. Such replacement lowers connectivity of junctions and destroys networks. The critical micelle concentration was also calculated. The results are compared with the reported experimental data on poly(ethylene oxide)-based associating polymers and hydrophobically modified cellulose derivatives.

Capsaicin and 8-nordihydrocapsaicin were readily converted into the corresponding monoglucosides (capsaicin β-d-glucopyranoside and 8-nordihydrocapsaicin β-d-glucopyranoside) with tetraacetyl-α-d-glucose fluoride (TAGF) in the presence of BF3·OEt2. Furthermore, capsaicin oligosaccharides and 8-nordihydrocapsaicin oligosaccharides were synthesized from their monoglucosides by a cyclodextrin glucanotransferase (CGTase)-catalyzed glycosylation for the preparation of higher water-soluble capsaicinoids.

The practical synthesis of vinyl p-coumarate (vinyl 4-hydroxycinnamate) and vinyl ferulate (vinyl 4-hydroxy-3-methoxycinnamate) was accomplished via a transesterification to the corresponding aromatic acid using vinyl acetate and a catalytic amount of PdCl2, followed by the lipase-catalyzed regioselective alcoholysis in EtOH.

Three new biotransformation products, artemisinic acid β- d -glucopyranosyl ester, 9-β-hydroxyartemisinic acid β- d -glucopyranosyl ester and 3-β-hydroxyartemisinic acid β- d -glucopyranosyl ester, were isolated from a cell culture of Artemisia annua following the administration of artemisinic acid.

Four new biotransformation products, 4-isopropyltropolone 2-O-β- d -glucoside, 4-isopropyltropolone 2-O-β- d -gentiobioside, 6-isopropyltropolone 2-O-β- d -glucoside and 6-isopropyltropolone 2-O- d -gentiobioside, were isolated from cell suspension culture of Eucalyptus perriniana following administration of β-thujaplicin. The chemical structures of all products were determined by 1 H and 13 C NMR and MS spectroscopy. It was also observed that the production ratio of biotransformation products was higher in iron-deficient medium than in the medium containing iron ion.

We successfully established hairy root cultures of Scutellaria baicalensis by direct inoculation on sterile seedlings with Agrobacterium rhizogenes pRil5834 harbouring pBI121. Transformation was proved by direct detection of the inserted T-DNA by the polymerase chain reaction. To determine the optimal medium for growth of hairy roots, the effects of five basal media were investigated; growth was best in B5 liquid medium. A new flavone glucoside, 5,7,2′,6′-tetrahydroxyflavone 2′-O-β-d-glucopyranoside 15 known flavonoids and five known phenylethanoids were isolated from the hairy root cultures of S. baicalensis for the first time. Their structures were elucidated by various spectroscopic methods.

Four UDP-glucosyltransfease (GTF) fractions were separated from the cultured cells of Eucalyptus perriniana , all of which exclusively produced β-thujaplicin 2- O -β- d -glucoside from β-thujaplicin (hinokitiol) in the presence of UDP-glucose (UDPG) as the sole glucose donor. An effective enzymatic system for repeated production of the monoglucoside has been developed by using an enzyme fraction as a water-insoluble biocatalyst in an enzyme membrane reactor (slurry reactor) equipped with an ultrafiltration membrane. The GTF also catalyzed the regioselective glucosylation of salicyl alcohol to salicin and of various polyphenols to naturally occurring pigments such as sugar-containing flavonoids. This study is the first to observe GTF activity in the enzyme fractions from the cultured cells of E. perriniana , which specifically catalyze the UDPG-dependent monoglucosylation of aromatic compounds and flavonoids.

To examine the biotransformation of (+)-catechin by the plant cultured cells of Eucalyptus perriniana, three new biotransformation products, (+)-catechin-3′-O-β-D-glucoside, (+)-catechin-5-O-β-D-glucoside and (+)-catechin-7-O-β-D-glucoside were isolated after 3 days incubation. The cultured cells of E. perriniana were found to be capable of glycosylation at the 5, 7-positions on the A ring and the 3′-position on the B ring of (+)-catechin.

Four new cadinene sesquiterpenes, named ganomastenols A-D, have been isolated from the cultured mycelia and its broth of Ganoderma mastoporum. Their structures were elucidated by spectral data.

Two new triglycosidic triterpene astragalosides, named agroastragaloside III and agroastragaloside IV, were isolated from the hairy root cultures of Astragalus membranaceus. From their spectroscopic data, the structures of the two compounds were elucidated as 3-O-β-(2′,3′- di -O- acetyl )- d -xylopyranosyl -6-O-β- d -glucopyranosyl -25-O-β- d -glucopyranosyl-cycloastragenol and 3-O-β-(2′-O- acetyl )- d -xylopyranosyl -6-O-β- d -glucopyranosyl -25-O-β- d -glucopyranosyl-cycloastragenol , respectively. Both are triterpenetridesmosides.

Agroastragaloside II, a new astragaloside was isolated from the hairy root culture of Astragalus membranaceus. Its structure was established as 3-O-beta-(2'-O-acetyl)-D-xylopyranosyl-6-O-beta-D-glucopyranosyl-(24S)- 3 beta,6 alpha,16 beta,24,25-pentahydroxy-9,19-cyclolanostane on the basis of spectroscopic data. Three known astragalosides, astragaloside II, isoastragaloside I and 3-O-beta-D-xylopyranosyl-cycloastragenol were also isolated.

Cultured Glycyrrhiza echinata L. (Leguminosae) cells produce a retrochalcone echinatin (4,4[prime]-dihydroxy-2-methoxychalcone) and its biosynthetic intermediate licodione [1-(2,4-dihydroxyphenyl)-3-(4-hydroxyphenyl)-1,3-propanedione, a dibenzoylmethane (keto form) or its enol tautomer ([beta]-hydroxychalcone)], when treated with elicitor-active substances, e.g. yeast extract. A microsomal fraction (160,000g pellet) prepared from yeast extract-induced suspension cultures of G. echinata catalyzed the formation of licodione from (2S)-liquiritigenin (7,4[prime]-dihydroxyflavanone) in the presence of NADPH and air. This licodione synthase activity was shown to be dependent on cytochrome P450 by its microsomal localization, requirement of NAD(P)H and O2 for activity, and inhibition by typical cytochrome P450 inhibitors. Licodione synthase activity transiently increased in the cells after treatment with yeast extract. When (2S)-naringenin (5,7,4[prime]-trihydroxyflavanone) and NADPH were incubated with the same microsomal preparation, a polar compound, which further converted into apigenin (5,7,4[prime]-trihydroxyflavone) when treated with acid, was produced. The reaction mechanism of licodione synthase is likely to be 2-hydroxylation of the flavanone molecule and subsequent hemiacetal opening and is possibly the same as the previously suggested mechanism of flavone synthase II from soybean and, furthermore, closely related to isoflavone synthase from Pueraria lobata.

A new astragaloside, named agroastragaloside I and four known astragalosides, acetylastragaloside I, astragaloside I, astragaloside III and astragaloside IV were isolated from the hairy root cultures of Astragalus membranaceus . The structures of these compounds were elucidated by the spectroscopic data.

We found a novel method to select anthocyanin-producing cells by a new means of cell staining. After staining with 0.2 ppm fluorescein isothiocyanate (FITC), the protoplasts from Aralia cordata cultured cells, which were composed of high anthocyanin-producing cells and non-producing cells, were observed to be distinguishable under a fluorescence microscope. The green fluorescence of FITC from the non-producing cells was clearly ascertained by the naked eye. On the other hand, the fluorescence of the anthocyanin-producing cells was completely missing. This phenomenon resulted from compensation of the green fluorescence (lambda max 525 nm) of FITC and the green light absorption (lambda max 530 nm) of anthocyanin. Although investigations of the flow cytometric method were developed on the basis of this phenomenon, the histograms of these protoplasts expressed the distinction between the anthocyanin-producing cells and the non-producing cells. In order to prove the technique, a highly productive cell line was selected from the heterogeneous populations of anthocyanin-producing or non-producing protoplasts from A. cordata cultured cells. The number of the sorted protoplasts containing anthocyanin was counted by the naked eye, the anthocyanin-producing protoplasts were approximately 90% in the whole protoplasts and the viability was 60-70%. Anthocyanin concentration the sorted protoplasts was 3-fold higher as compared with the protoplasts before sorting. The anthocyanin content of the cell line selected by this method was 7.7 +/- 0.6%/g dw.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

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-Skoog's 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.

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.

Ginseng (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.

The regenerated plants obtained from Strophanthus divaricatus calli contain 10 cardenolides, accumulating seven of them in the original plants. At

On administration of 18 beta-glycyrrhetinic acid to hairy root cultures of Panax ginseng, three new biotransformation products, 30-O-[beta-D-glucopyranosyl-(1-->2)-beta-D- glucopyranosyl]18 beta-glycyrrhetinic acid, 30-O-(6- O-malonyl-beta-D-glucopyranosyl)18 beta-glycyrrhetinic acid and 3-O-[6-O- malonyl-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl]18 beta-glycyrrhetinic acid, were isolated together with three known compounds. Ginseng hairy roots showed the biotransformation abilities of glycosylation and malonylation to 18 beta-glycyrrhetinic acid.

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.

An integrated system has been constructed to instantly identify and efficiently sort the heterokaryons formed by plant protoplast fusion. The system is composed of the following functions: a) a transport system, b) an electro-manipulator, c) a cell harvester, d) a flow cytometer/cell sorter, and e) a control device. The conditions for an efficient and reproducible enrichment of the heterokaryons have been investigated by this system using the fluorescein isothiocyanate stained protoplasts preparing from Glycyrrhiza glabra cell cultures and unstained protoplasts of Abrus precatorius cell cultures which contain a large quantity of chlorophyll.

Ginseng (Panax ginseng) hairy-root culture, established by transformation with the Ri plasmid of Agrobacterium rhizogenes, had a higher potential to biotransform (RS)-2-phenylpropionic acid (PPA) to (RS)-2-phenylpropionyl β-d-glucopyranoside (1) (71% conversion ratio), (2RS)-2-O-(2-phenylpropionyl)-d-glucose (2) (8%), (2S)-2-phenylpropionyl 6-O-β-d-xylopyranosyl-β-d-glucopyranoside (3) (10%) and a myo-inositol ester of (R)-2-phenylpropionic acid (4) (5%). Moreover, the hairy root excreted about a half of the conversion products, 46.8%. The continuous glycosylation of PPA was carried out using a bioreactor with ginseng hairy root, and the continuous long-term reaction for 2 months was successfully made at a high conversion ratio, 30% or more on average.

The examination of strain-specific triterpenoid components pattern was made in three strains of Ganoderma lucidum; Sekishi, Shishi, Kokushi (all Japanese names). Comparative examination on triterpenoid patterns of strains of Ganoderma lucidum by HPLC revealed that Sekishi and Shishi have similar ganoderic acid derivatives, but Kokushi has no ganoderic acid derivatives. Ganoderic acid V1, isolated as a main triterpenoid component of Shishi, is a new ganoderic acid derivative: (24E)-3β,20ξ-dihydroxy-7,11,15-trioxo-5α-lanosta-8,24-dien-26-oic acid.

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.

ウド培養細胞はアントシアニン色素生産に関して全く光を必要としない特徴を有する.培養条件の異なる3種類のウド培養細胞からアントシアニン系の赤色色素を抽出し,粗精製赤色色素を得た.この色素の酸性水溶液は鮮やかな赤色を呈するため,新たな天然赤色色素としての実用化の可能性を検討した,種々の基礎的検討の結果,pH 2.2～6.0で赤色から赤橙色を示し, pH 7.0～9.0では赤紫色から紫色の色調を呈した.数時間経過後の各pH水溶液は,酸性領域では非常に安定に,中性付近でも比較的安定的にその色調を維持していた.耐熱性に関しても, 95℃, 2時間の熱処理前後でその色相の変化は小さく,非常に安定していることが明らかとなったが,紫外線に対する耐光性はシソ色素に比べ劣った.食品用着色料として不可欠な安全性に関しては,まだ初期試験の段階ではあるが,突然変異誘発性試験および有害な重金属類の定量分析から,その安全性が確認された.さらに清涼飲料を試作して食品用着色料としての実用性を評価した結果,耐光性面にやや問題があるものの,実用化の可能性が高いことがわかった.今後培養のスケールアップ,耐光性面の改善と各種食品への応用試験,さらに安全性面での検討が進めば,新たな食品用着色料としての開発が可能となるであろう.

Factors affecting α-tocopherol production using safflower (Carthamus tinctorius) cells were studied from the engineering aspects for plant cell culture. The specific production rate was evaluated as a function of rate-limiting factors. The conditioning factor released from cells, dissolved oxygen (DO) and medium components were considered as the limiting factors responsible for the specific production rate. Increasing the conditioning factor enhanced α-tocopherol production. Increasing DO concentration up to 9 mg-O2/l also caused a linear increase in specific production rate. The specific production rate in batch cultivation decreased, however, at a constant DO concentration with a sufficient amount of the conditioning factor. In repeated batch cultivation, the specific production rate was recovered by the addition of fresh medium. These results showed that an essential component in the medium was exhausted at an early stage of the batch cultivation and that the medium-feeding operation with sufficient CF and DO concentrations was required to maintain high productivity. By repeated batch cultivation, the content of α-tocopherol in the cell was increased to 9 mg/100 g-dry cell, which was considerably higher than that in natural safflower seeds.

A novel transformation of α-substituted benzylcyanides by hydroxylation of benzyl sites using cultured cells of cotton, Gossypium hirsutum, producing alkano- or benzophenones via presumably α-cyanohydrin is demonstrated. Also regioselective hydroxylation of 4 S -(−)-perillyl alcohol and 3 S -(−)-citronellol by cultured suspension cells of Catharanthus roseus is reported.

A simple and new basket-shaped unit for agitation made of stainless steel (EGSTAR), in which immobilized coffee cells in Ca-alginate gel beads were packed, was placed in a jar fermentor (System-1). This system allowed the plant cells to grow submersed in the unit even at high agitation speed (650 rpm). Only a small amount of cells existed out of the EGSTAR. Most of the purine alkaloids produced were released into the medium. Suspended coffee cells in the jar fermentor were also possibly immobilized onto a polyurethane foam sheet fixed inside the net of the EGSTAR (System-2). The total cells in System-2 biotransformed theobromine to caffeine (77.9%). Other plant cell suspensions were also immobilized as efficiently as were the coffee cells in this system. Thus, System-2 is a simple and convenient system for immobilization of plant cells to produce secondary metabolites.

Cultured cells of Thuja dolabrata var. hondai, which were able to produce β-thujaplicin in high yield, were induced and selected. The effective production and extraction of β-thujaplicin has been achieved using the cultured cells in a semi-continuous culture system. This system needs only the whole cells without immobilizing them and the flesh medium in each batch production. The productive efficiency did not decrease during repetitive batch production.

Biotransformation of paclitaxel by cell suspension cultures of Marchantia polymorpha was studied and it was found that liverwort cultures convert paclitaxel to 7-epi-paclitaxel in good yield and regioselectively hydrolyses the ester group at the 10-position of paclitaxel.

The regioselective acylation of naturally occurring plant pigments with aromatic acids such as caffeic acid and p -coumaric acid was examined by an enzymatic reaction system from cultured cells of Ipomoea batatas . Isoquercitrin, a flavonoid glucoside, was converted to isoquercitrin 6″- O -caffeate by the enzymatic system. Chrysanthemin, an anthocyanin, was also acylated to the corresponding caffeate ester. This enzymatic method should prove useful for the synthesis of acylated flavonoid glucosides such as isoquercitrin caffeate, whose productivity is low using lipase-catalyzed transesterification.

The structures of two new metabolites, cryptoporic acids H and I isolated from Ganoderma neo-japonicum culture, were established from spectral data and by single-crystal X-ray analysis. Cryptoporic acid H was also isolated from the culture broth of Cryptoporus volvatus whose fruit body contains cryptoporic acids A–G.

A hot aqueous extract of Coptidis Rhizoma had an inhibitory effect on the bacterial collagenase from Clostridium histolyticum. Active principles were isolated by silica gel column chromatography from the CHCl3 extract. Consequently, two inhibitors obtained were identified with the chloride of berberine and coptisine. The concentrations of the berberine and coptisine in the assay mixture to give 50% inhibition (IC50) were 0.73 mM and 0.16 mM, respectively. The type of inhibition by coptisine chloride was shown to be a mixture type from Lineweaver-Burk plots. Tetrahydroberberine, a reduction product of berberine chloride, had no inhibitory effect. This result suggests that the quaternary nitrogen of the alkaloids plays an important role in inhibitory activity.

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.

Biotransformation products of digitoxigenin by cell suspension cultures of Strophanthus intermedius were isolated and their structures elucidated as 3-epidigitoxigenin, 3-epi-17βH-digitoxigenin, gitoxigenin, periplogenin, 3-epigitoxigenin, 3-epiperiplogenin and digitoxigenin β- d -glucoside, respectively. Furthermore, 3-epi-17βH- periplogenin, 3-epidigitoxigenin β- d -glucoside and digitoxigenone were identified by TLC and HPLC. Biotransformation reactions of the digitoxigenin molecule by plant cell cultures are summarized and discussed comparatively.

Effects of tissue cultured ginseng on the function of the stomach and small intestine were compared with those of cultivated ginseng. Fifty percent ethanol extracts of the tissue cultured and cultivated ginseng stimulated gastrointestinal propulsion in mice. The tissue cultured ginseng also inhibited ulcer formation induced by water immersion and restraint stress, and ligature of the pylorus. In contrast, the cultivated ginseng showed no such inhibitory action.

The effect of light on caffeine production by Coffea arabica cells was investigated using chemical actinometry for the purpose of industrial application of plant cell cultures. Caffeine production by the Coffea arabica cells was greatly increased by light. About a six-day irradiation period was required to increase the caffeine production in a batch culture. Caffeine production significantly increased at a low light irradiation rate of 0.11 J/L/s. Meanwhile, cell growth was suppressed by increasing the irradiation rate. Maximum production was achieved at a moderate irradiation rate of 0.70 J/L/s in a 20-day batch culture. It was shown there was a light irradiation rate that optimized production. Since long-term continuous light greatly suppressed cell growth, the culture was divided into two stages: the production period in the light and the growth period in the dark. The high production and good growth were maintained for 65 days.

Effects of the tissue cultured and cultivated ginseng on gastric secretion and pepsin activity were investigated. Fifty percent ethanol extracts of both cultured and cultivated ginsengs reduced gastric secretion and acid output in pylorus-ligated rats. They did not affect pepsin activity. The tissue cultured ginseng inhibited histamine and pentagastrin-induced acid secretion in rats, whereas the cultivated ginseng showed no such effect. They also suppressed acid secretion induced by 2-deoxy-D-glucose and baclofen [beta-(p-chlorophenyl)-gamma-aminobutyric acid], which are known to stimulate gastric acid secretion via the central nervous system. However, they had no effect on acid secretion induced by vagal stimulation. These results suggest that both tissue cultured and cultivated ginsengs may have an inhibitory effect on gastric secretion. The effect seems to be due to the inhibition of acid secretion via the central nervous system.