(−)-Maglifloenone,a novel spirocyclohexadienone neolignan and other constituents from Magnolia liliflora

A new neolignan designated (?)-maglifloenone and the known one futoenone, both of which contain the rarely occurring spirocyclohexadienone skeleton, have been isolated together with the tetrahydrofuranolignan (+)-veraguensin, an optically inactive tertiary base taspine and β-sitosterol from the leaves and twigs of Magnolia liliflora. The structure and stereochemistry of (?)-maglifloenone have been deduced from the spectral data and the mass fragmentation of (?)-maglifloenone and futoenone have been rationalized. This is the first report of two neolignans of spirocyclohexadienone skeleton and of taspine from the Magnoliaceae family and the second report of the natural occurrence of futoenone.     

Isolation and identification of littorine from hairy roots of Atropa belladonna

A hairy root clone (M8) of Atropa belladonna, producing high levels of tropane alkaloids, was established by transformation with Agrobacterium rhizogenes (MAFF 03-01724). Littorine, an intermediate of tropane alkaloids, was detected by high-performance liquid chromatography and gas chromatography-mass spectrometry in the alkaloid fraction of the hairy roots and identified by nuclear magnetic resonance analysis. Littorine was also detected in the non-transformed root culture of A. belladonna. Received: 18 March 1998 / Revision received: 15 June 1998 / Accepted: 3 August 1998     

Manipulating indole alkaloid production by Catharanthus roseus cell cultures in bioreactors: from biochemical processing to metabolic engineering

Catharanthus roseus plants produce many pharmaceutically important indole alkaloids, of which the bisindole alkaloids vinblastine and vincristine are antineoplastic medicines and the monoindole alkaloids ajmalicine and serpentine are antihypertension drugs. C. roseus cell cultures have been studied for producing these medicines or precursors catharanthine and vindoline for almost four decades but so far without a commercially successful process due to biological and technological limitations. The research thus focused on the one hand on engineering the bioreactor process on the other engineering the cell factory itself. This review mainly summarizes the progress made on biochemical engineering aspects of C. roseus cell cultures in bioreactors in the past decades and metabolic engineering of indole alkaloid production in recent years. The paper also attempts to highlight new strategies and technologies to improve alkaloid production and bioreactor performance. Perspectives of metabolic engineering to create new cell lines for large-scale production of indole alkaloids in bioreactors and effective combination of these up- and down-stream processing are presented.     

Biotherapeutic potential and mechanisms of action of colchicine

Cancer is a clinical situation caused by uncontrolled cell division and is responsible for a large number of deaths worldwide. Colchicine is a classical antimitotic, tubulin-binding agent (TBA) which is being explored for its antitumor activities, although its tubulin-binding ability leads to some toxicity toward normal cells proliferation. Colchicine derivatives are considered as potent antitumor compounds with less toxicity compared to colchicine. Derivatives with substituted functional groups at A-ring (methoxy), B-ring (acetamide) or C-ring (methoxy) have been synthesized via chemical and microbial routes and show modified bioactivities and altered tropolonic functionality. Earlier reports, in combination with our group’s research findings, suggest that microbial biotransformation is an efficient choice for the production of bioactive colchicine derivatives. This route has gained significant interest in the mass production of regio-specific, cost-effective, safe and eco-friendly derivatives. The present review paper critically analyzes and discusses the development and application of colchicine derivatives as a potent antitumor molecule and their production through a microbial transformation process. The information provided in this review might assist in the stimulation of new ideas regarding the development of alternative therapeutic agent(s) for cancer treatment.     

Isolation of five polymorphic microsatellite markers in Utetheisa ornatrix (Lepidoptera: Arctiidae)

We isolated five polymorphic microsatellite markers for the arctiid moth Utetheisa ornatrix as part of an effort to investigate the role of inbreeding in the degree of polyandry seen in natural populations of the moth. We tested the primers on 105 individuals collected from scrub habitat in central Florida. These microsatellite loci provide a new research tool for understanding the population structure and reproductive behaviour of U. ornatrix.     

Alkaloid distribution and catabolism in Cephalotaxus harringtonia

Cephalotaxus harringtonia produces a variety of antitumor alkaloids that are distributed throughout the tree. In a young plant grown in a controlled environment, the concentration of free alkaloids (homoerythrina alkaloids and cephalotaxine) did not increase with age, whereas the concentration of cephalotaxine esters (harringtonine, deoxyharringtonine, isoharringtonine and homoharringtonine) increased roughly 5-fold. Total alkaloid concentrations increased in the older leaves of the plant and decreased in the older stems. Physiological stress (pruning) causes hydrolysis of part of the stored alkaloid esters to free cephalotaxine within one week. In 4 out of 5 field-grown trees environmental factors caused complete ester hydrolysis and, in addition, the oxidation of cephalotaxine to 11-hydroxycephalotaxine and drupacine and of homoerythrina alkaloid to its epoxy derivative. This shows that the alkaloids in this perennial tree are not inert storage products, but are under metabolic control.     

Parental Body Mass as a Determinant of Egg Size and Egg Output in an Arctiid Moth (Utetheisa ornatrix)

Females of the moth Utetheisa ornatrix (family Arctiidae) mate preferentially with larger males. As a consequence, females have larger sons and daughters, which have been shown to be more acceptable in courtship and more fecund, respectively. We demonstrate that mating with larger males results in accelerated oviposition by the female on the day after mating and that females are intrinsically prone to lay larger eggs in the first days after mating. Both these additional size-dependent effects have potential adaptive consequences.