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3,5-O-dicaffeoyl-4-O-malonilquinic acid (1) (irbic acid) has been isolated for the first time from cell cultures of Centella asiatica and till now it has never been reported to be present in the intact plant. Evidence of its structure was obtained by spectroscopic analyses (MS/NMR). Besides 1, cell cultures produce also the known 3,5-O-dicaffeoylquinic acid, chlorogenic acid, and the triferulic acid 2 (4-O-8′/4′-O-8″-didehydrotriferulic acid). Biological activities were evaluated for compound 1, which showed to have a strong radical scavenging capacity, together with a high inhibitory activity on collagenase. This suggests a possible utilization of this substance as a topical agent to reduce the skin ageing process.

In the present study callus cultures of Zanthoxylum stenophyllum were initiated in vitro and the effect of different growth regulators and elicitors was tested both upon callus growth and secondary metabolite production. On a medium containing naphthalenacetic acid (NAA), kinetin and 2,4 dichlorophenoxyacetic acid (2,4D), a yellowish and friable callus was obtained from 90% of cotyledon explants, while no callus appeared from other portions of the seedlings. The time course of callus growth and secondary metabolite accumulation was followed after subculturing the established callus culture on different media containing various hormonal combinations. Results indicate that medium containing NAA and a higher concentration of 2,4-D compared to maintenance medium gave the highest stimulation of callus growth, suggesting that this auxin has a critical role in influencing growth. Addition of an organic nitrogen source such as casein hydrolysate also had a positive effect on growth. HPLC analysis of methanol extractable secondary metabolites from Z. stenophyllum calli grown on different media showed that phytohormones and nutrients were able to modify the chromatographic pattern of compounds. Calli grown on the medium giving the highest stimulation of growth show a reduced accumulation of some secondary products. Under the same hormonal conditions, the presence or absence of casein also altered the metabolites produced, both qualitatively and quantitatively. In response to elicitation by methyl jasmonate (MJ), metabolite production was different for the different classes of compounds, and hormonal composition of the culture medium turned out to be very important in determining the response to MJ. Thus, results confirm the importance of the reciprocal interactions between hormones, nutrients and elicitors when attemps are made to enhance secondary metabolite accumulation in in vitro cultures.

Inhibitory effects by addition of aqueous extracts of soy flour to an active Briggs-Rauscher mixture are reported. The effect consists of an immediate cessation of oscillations, but, after some time, the oscillatory behavior is regenerated with amplitude and frequency different from those observed in a reference mixture. The inhibition time depends linearly on the concentration of substances contained in the extract in a wide range of concentration. The inhibitory effects are due to the high free-radical scavenging activity of substances contained in the soy flour. Two preponderant products contained in the soy flour extract were identified and characterized as malonyldaidzin and malonylgenistin. The antioxidant activity of these isoflavones contained in the extracts was determined on the basis of the inhibition time. A qualitative mechanistic explanation of the inhibitory effects is given. Our findings are decisive indirect evidence of involvement and important role played by HOO. radicals in establishing oscillations in the Briggs-Rauscher (BR) system. The linear relationship between the inhibition time and the whole-mass concentration of antioxidant contained in soy extracts added to a BR mixture is an indication of the possibility to develop and implement an analytical procedure for monitoring the activity of antioxidant scavengers of free radicals based on the oscillating Briggs-Rauscher reaction.

Ge-gen (Radix Puerariae; RP) is used in traditional oriental medicine for various medicinal purposes. The drug is the root of a wild leguminous creeper, Pueraria lobata (Willd) Ohwi. It possesses a high content of flavonoid derivatives, the most abundant of which is puerarin (PU). Here, using the enhanced chemiluminescence technique based on horseradish peroxidase and a luminol-oxidant-enhancer reagent, we evaluated in vitro the antioxidant activity of PU and RP crude extract. Both biological samples inhibited the steady-state chemiluminescent reaction in a dose-dependent fashion. However, different inhibition mechanism were postulated, since only RP behaved like conventional antioxidants. This activity was supposed to be due the presence of compounds other than PU in the crude extract. Using each of the specific substrates to different cytochrome P450 (CYP) isoforms or the regio- and stereo-selective hydroxylation of testosterone as polyfunctional probe we found that when intragastrically administered in male Wistar rats, PU (100 or 200 mg/kg b.w.) and RP (700 or 1,400 mg/kg b.w.) significantly altered hepatic CYP-linked monooxygenases. While both CYP content and NADPH-(CYP)-c-reductase activity were significantly increased in all situations, a complex pattern of CYP modulation was observed, including both induction (PU: CYP2A1, 1A1/2, 3A1, 2C11; RP: CYP1A2, 3A1, 2B1) and inactivation (PU and RP: CYP3A, 2E1, 2B1), the latter being due to either parental agents or metabolites, as demonstrated by in vitro studies. Overall, these findings indicate that RP contains compounds with potent antioxidant activity and that both PU and RP impairs CYP-catalysed drug metabolism.

Cell cultures of Papaver somniferum var. setigerum were shown to carry out the biotransformation of silybin into silybin -7-O-β- d -glucopyranoside .

Structures of oxepino[5,4,3c,d]indole derivatives (2, 3) and 3,4-disubstituted indoles (4, 5) resulting from biotransformation of chanoclavine by Euphorbia calyptrata cell culture have been elucidated by NMR and mass spectroscopy.

Four new diterpenoids, helioscopinolides F (2), H (4), I (5), and L (6), were isolated from three different cultured cell lines of Euphorbia calyptrata var. involucrata. Helioscopinolide B (1) and jolkinolide E (3), previously found in Euphorbia helioscopia and Euphorbia jolkini, respectively, were also isolated from the same cultures. Structures were identified by spectroscopic methods.

Ergot alkaloids agroclavine and elymoclavine have been modified using plant cell cultures exhibiting high peroxidase activity. Setoclavine and isosetoclavine have been isolated from media after transformation of agroclavine on a semipreparative scale. 10-Hydroxyelymoclavine resulted from similar treatment of elymoclavine.

The isolation and structure elucidation of a new ergot peptide alkaloid, ergobine {1}, from submerged cultures of Claviceps purpurea strain 231 FI, are described. Its purification and identification were achieved by feeding experiments with a labelled precursor. The structural details have been established through chemical degradation, uv spectroscopy, hplc, amino acid analyses, 1 H nmr, eims, fdms, and its isomerization to ergobinine

In order to identify diterpenoids (Helioscopinolides) produced in trace amounts by wild type cell cultures of Euphorbia calyptrata, three cell lines characterized by high production of the target metabolites have been selected. Cell lines were obtained by selection in media with different hormone composition.

A new spiro-oxa dimer of lysergene (3) has been isolated as a product of the biotransformation of lysergene (1) by Euphorbia calyptrata suspension cell culture. Its structure has been determined by spectral methods.

Years ago a review on ergot alkaloids (EA) appeared with the title: “The biosynthesis of ergot alkaloids; the story of the unexpected” (Floss, 1980). I don’t believe that any other title could be more appropriate since the entire history of EA research, from the discovery of ergotamine almost a century ago until the present, has truly been the history of the unexpected.

Crude methanolic extracts from both root and cell cultures of Euphorbia calyptrata were investigated and found to be active on the CNS. An active fraction was isolated from the methanolic extract of suspension cultures; this possesses significant depressant activity on the CNS. When compared with the crude methanolic root extract, this fraction showed the presence of some common products, four of which were isolated and characterized as helioscopinolides A, C, D, and E. The pure products, administered intraperitoneally to mice, showed different activities on the CNS. Helioscopinolide C showed a clear depressant activity, helioscopinolide E a mild, short depressant effect, while helioscopinolides A and D had an opposite excitatory effect.

Einige neue durch Biosynthese erhaltene Analoga des Vitamins B12 wurden untersucht. Durch spektrophotometrische Untersuchung im ultravioletten und infraroten Licht gelang es, die Benzimidazol-Komponente dieser Substanzen als 5(6)-Athyl-6(5)-n-propyl-benzimidazol, 5.6-Tetramethylen-benzimidazol, 5(6)-Amino-6(5)-methyl-benzimidazol zu identifizieren. Diese letzte Verbindung ist an der Struktur zweier Cobalamin-Analoga beteiligt.

By feeding14C-daunorubicin to a doxorubicin-producing mutant ofStreptomyces peucetius, labelled doxorubicin and 13-dihydrodaunorubicin have been obtained; this indicates that the former compound is a precursor of both the latter ones in the fermentation process.

1. Ribosome-inactivating proteins were found in high amounts in one line of cells of Phytolacca americana (pokeweed) cultured in vitro and, in less quantity, in lines of Saponaria officinalis (soapwort) and of Zea mays (corn) cells. 2. The main ribosome-inactivating protein from pokeweed cells was purified to homogeneity. It is a protein with Mr 29,000 and basic pI, similar to the ‘pokeweed antiviral protein’ (PAP), a ribosome-inactivating protein from pokeweed leaves. We propose to call the pokeweed antiviral protein isolated from pokeweed cells PAP-C. 3. PAP-C inactivates ribosomes in a less-than-equimolar ratio, thus inhibiting protein synthesis by a rabbit reticulocyte lysate with an IC50 (concentration causing 50% inhibition) of 0.067 nM (2 ng/ml), and modifies rRNA in a manner apparently identical to that of ricin and other ribosome-inactivating proteins. It inhibits protein synthesis by intact cells with an IC50 of 0.7-3.4 microM, and is toxic to mice with an LD50 of 0.95 mg/kg.

A strain ofClaviceps purpurea, labelled 231 F.I., produced in submerged culture 1200 μ/ml of a mixture of peptidic alkaloids composed for 30% by β-ergokryptine. Cultural media, conditions of culture and development features of a typic fermentation are reported.

Three strains of Claviceps purpurea (Fr.) Tul., isolated from sclerotia grown on rye, produce under submerged conditions ergocryptine and ergotamine, ergocornine and ergosine, and ergocristine, respectively. All of the strains either lacked the ability to produce conidia or formed them sparingly, but they accumulated large quantities of lipids and sterols. The fermentations are typically divided into two phases. The first is characterized by the rapid utilization and exhaustion of the phosphate contained in the medium, rapid uptake of ammonium nitrogen and of citric acid, rapid growth, and low alkaloid production; the second phase is characterized by slower growth and by a marked accumulation of lipids, sterols, and alkaloids.

Un ceppo diClaviceps purpurea indicato con la sigla 275 F.I. produce in coltura sommersa 1100–1500μg/ml di una miscela di alcaloidi peptidici costituita principalmente da ergotammina (80%). Sono riportati i terreni colturali, le condizioni di coltura e l'andamento di una tipica fermentazione.

Claviceps purpurea 275 F.I. fed with α-aminobutyric acid produces ergostine with the corresponding α-hydroxy-α-aminoacid undiluted by endogenous aminoacid. Almost all the α-aminobutyric acid not incorporated into the ergostine remains unchanged in the medium. The significance of these results in the biosynthesis of ergot alkaloids is discussed.

Feeding experiments with specifically labelled precursors showed that in ergot alkaloids biosynthesis, the isoprenylation of tryptophan occurs without intermediate hydroxylation.