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Atropa belladonnaleaf disks were infected by a wild strain Agrobacterium rhizogenes15834 harboring the Ri-TL-DNA and by a disarmed Agrobacterium tumefaciensstrain harboring a construction with only rolABCand npt IIgenes. Thirteen root lines were established and examined for their growth rate and alkaloid productivity to evaluate the possible role of rolgenes in morphological differentiation and in tropane alkaloid formation. A great diversity has been observed in the growth rate of these 13 root lines. The root biomass increased up to 75 times. The total alkaloid contents were similar in the root lines obtained by infection with A. rhizogenes15834 and A. tumefaciensrolABC. The last ones accumulated between 4 (1.1 mg g−1DW) and 27 (8 mg g−1DW) times more alkaloids than the intact roots (0.3 mg g−1DW). This work has shown that the rolABCgenes were sufficient to increase tropane alkaloid production in A. belladonnahairy root cultures.

In order to prepare an active enzyme extract of UDP-glucose: scopoletin glucosyltransferase from suspension cultured cells of Solanaceous species, the analytical conditions were improved, extraction of crude enzyme optimized, and cells of Duboisia myoporoides, Nicotiana plumbaginifolia, and Solanum avicularewere compared as sources. Cells of Duboisiagave best yields, which could be further increased by precultivation in the presence of phenobarbital. For extraction of crude enzyme, Tris and phosphate buffers were compared, with addition of mercaptoethanol, EDTA and ascorbate. The activity of SGTase exhibited 14.10−3nKat. mg−1of proteins using 130 μM of scopoletin as a substrate.

The alkaloid content and profile of roots and aerial parts of diploid, haploid and hypohaploid plants of Nicotiana plumbaginifolia regenerated in vitro from leaf explants was determined by enzyme immunoassay and gas chromatography. Roots and buds separately neoformed in vitro were examined by the same methods. An interesting trait was found: buds, even without roots, contained alkaloids. Each of the tested hypohaploids exhibited a peculiar alkaloid content and profile compared to diploid and haploid genotypes, confirming the novel character of these hypohaploids. No correlation was observed between the degree of ploidy and the alkaloid content or profile.

From a solanaceous cell suspension an acetophenone glycoside, androsin, has been isolated along with one polyphenol glycoside, scopolin. The androsin presence is described for the first time in solanaceous cell suspension.

Six cell suspension cultures established from different organs of Thevetia peruviana were initiated under various growth conditions. Even after two years of subculture, cardenolides proved to be present in all the strains. The cardenolide content varied from one strain to another according to the nature of the original explant and was always lower in comparison with that of the seeds of the original plant. Kinetic studies showed that the cardenolide content varied over a complete cycle of culture.

Leaves of Nicotiana tabacumL. cv Samsunwere selected because of the volatile nature of their active principle, nicotine. They were dried by four different methods: air‐dried, oven‐dried at 60°C, freeze‐dried, and dried in a microwave oven. The four samples of dried leaves were compared as to their microscopical characters and alkaloid content. After drying by microwaves, it remained possible to identify the leaves by their botanical characteristics. Their alkaloid content was qualitatively unchanged and quantitatively slightly superior to that of leaves dried by the other methods.