C. Codina

Callus induction, somatic embryogenesis and organogenesis in Narcissus confusus: correlation between the state of differentiation and the content of galanthamine and related alkaloids

Abstract In vitro cultures from two strains of Narcissus confusus (Amaryllidaceae) initiated from mature seeds were screened for their ability to produce alkaloids. Protocols for callus induction, somatic embryogenesis and organogenesis were established. The alkaloid contents were determined by HPLC. Undifferentiated calli produced small amounts of galanthamine, which increased with the degree of tissue differentiation. Scanning electron micrographs of the cultures at different stages of development were made. Embryogenic friable calli were maintained in culture for more than 2 years, retaining a high regeneration capability. All regenerated plants showed normal morphological characteristics.

Alkaloids from Cyrtanthus elatus

The alcoholic extract of the fresh bulbs of Cyrtanthus elatus yielded zephyranthine (1) and 1,2-O-diacetylzephyranthine (2), together with three other known alkaloids. Complete assignment of 1H and 13C NMR spectra of compounds 1 and 2 was done by employment of two-dimensional NMR techniques.

Alkaloids from Ammocharis tinneana

Abstract Sixteen alkaloids have been isolated from fresh bulbs of Ammocharis tinneana (Amaryllidaceae), seven of which contain a 1,2β-epoxide group. 6α-Hydroxycrinamidine and 6α-hydroxyundulatine are reported here for the first time from a natural source. The structures and stereochemistry of these new alkaloids have been determined by physical and spectroscopic methods. 1 H and 13 C NMR spectra of flexinine, 1,2β-epoxyambelline and 11- O -acetyl-1,2β-epoxyambelline were completely assigned by means of 2D NMR techniques.

Occurrence of colchicine derivatives in plants of the genus Androcymbium

Androcymbium gramineum plants were phytochemically investigated for alkaloids. Two major alkaloids, colchicine and demecolcine, were isolated from the whole plant, and 2-demethylcolchicine, 3-demethylcolchicine, N-formyl-N-deacetylcolchicine and colchifoline have also been identified by HPLC analysis. This is the first report of demecolcine in A. gramineum, and of colchifoline in the genus Androcymbium. In addition, seeds of Androcymbium gramineum, Androcymbium hierrense , Androcymbium palaestinum, Androcymbium psammophilum , Androcymbium rechingerii , and Androcymbium wyssianum were also investigated for their alkaloid content for the first time. All were found to contain colchicine and colchicoside.  2003 Elsevier Science Ltd. All rights reserved.

Galanthamine production in “shoot-clump” cultures of Narcissus confusus in liquid-shake medium

Galanthamine (GAL) is increasingly used in the treatment of Alzheimers disease. We have attempted to develop a method of producing this alkaloid using in vitro cultures of Narcissus confusus plants. The “shoot-clump” culture in liquid medium was shown to be an appropriate method for the micropropagation of this bulbous plant. The complete process included three steps:1.culture of “twin-scales” starting from the bulbs;2.culture of the newly formed shoots in a medium for bud proliferation (Murashige Skoog+1 mg l-1 of 2,4-dichlorophenoxyacetic acid+5 mg l-1 of benzyladenine), and3.culture of “shoot-clumps” in a liquid-shake medium. Here we describe the effect of the addition of trans-cinnamic acid, a precursor in the biosynthesis of the Amaryllidaceae alkaloids, on the production of galanthamine and related alkaloids, and also on the growth of the “shoot-clump” culture. The production of galanthamine was found to be inhibited by the addition of the precursor, which promoted the production of the other alkaloid in the same biosynthetic pathway, N-formyl-norgalanthamine. The total production of galanthamine in the control cultures in day-long photoperiod was 2.50 mg per culture, of which 1.97 mg per culture were released into the medium.

Alkaloids from Narcissus bujei (Amaryllidaceae)

Eleven alkaloids have been isolated from whole plants of Narcissus bujei (Amaryllidaceae). The alkaloids 11-Oacetylhaemanthamine and bujeine are reported for the first time. The structure and stereochemistry of these new alkaloids have been determined by physical and spectroscopic methods. The X-ray diAraction analysis of O-methyllycorenine hydrochloride has been performed. # 1998 Elsevier Science Ltd. All rights reserved.

Micropropagation of the rare Eucrosia stricklandii (Amaryllidaceae) by twin-scaling and shake liquid culture

Summary Bulbs of E. stricklandii were introduced into in vitro culture by the twin-scaling technique. Different Murashige and Skoog (MS) media supplemented with 0.5% w/v activated charcoal, naphthaleneacetic acid (NAA)/benzyladenine (BA) 0.54/4.44 μM or NAA/Thidiazuron (TDZ) 0.54/0.45 μM were used for shoot induction. Media with different combinations of 2,4-dichlorphenoxyacetic acid (2,4-D) and BA were tested during the secondary multiplication. The shoots obtained in the multiplication step were then transferred to a liquid medium with different sucrose concentrations (from 0.088 to 0.351 M) to increase biomass. Shoot bulbing was induced in 0.263.M sucrose semi-solid medium without growth regulators. Several media containing different concentrations of NAA (ranging from 0 to 5.37 μM) combined with various sucrose concentrations (from 0.044 to 0.263 M) were also tested for root induction and the bulblets were finally transplanted to soil. The best induction of shoots was obtained in the media with activated charcoal or with TDZ, but those treated with activated charcoal showed a better regeneration rate and the shoots were better formed. The best development of new shoots was obtained in the medium containing 0.45 and 4.44 μM of 2,4-D and BA, respectively. 0.175–0.263 M sucrose in the liquid medium appeared to be the most appropriate condition for increase in biomass. Rooting was promoted by low NAA concentrations (0.537–1.343 μM), and 0.175 M sucrose was the best treatment for root development.

In vitro production of bulblets of Cyrtanthus loddigesianus and Cyrtanthus speciosus

Summary The micropropagation of Cyrtanthus loddigesianus and C. speciosus was carried out by the twin-scaling technique. In both species the best induction of shoots was obtained on the Murashige and Skoog (MS) medium containing 5.37 μM of a-naphthaleneacetic acid (NAA) and 22 20 μM of benzyladenine (BA), whereas the best regeneration rate was found in the medium with 0.5% of activated charcoal. High doses of NAA/BA (5.37 μM/8.88 μM) were also found to be the most effective for developing new shoots in both species. 90 g l–1 and 30 g l–1 of sucrose in the liquid medium appeared to be the most appropriate condition to increase the biomass of the shoot-clumps of C. loddigesianus and C. speciosus, respectively. Rooting was promoted by low NAA concentrations (1.34 or 2.68 μM) in C. loddigesianus bulblets, and high concentrations (5.37 μM) in C. speciosus bulblets. Before transferring the obtained plantlets to the ex vitro conditions some were cold-treated to break possible dormancy. The plantlets were acclimatized in different chambers, and finally transferred to soil, where they showed 100% survival.

Alkaloid Screening of Plants of Catalonia (Spain) III

AbstractEighty plant extracts were screened for the presence of both tertiary and quaternary alkaloids. 9 species were found to contain alkaloids and 8 of these are reported for the first time.

Free amino acids and alkaloid content in snapdragon plants grown with nitrate, urea or ammonium nutrition

Abstract The effect of different nitrogen sources (urea, nitrate and ammonium) on the free amino acids and alkaloid content in leaves and roots of snapdragon (Antirrhinum majus) was studied. The nitrate treatment produced the highest plant dry weights, and urea the lowest. The all ammonium grown plants finished their biologic cycle one month earlier than the nitrate plants. Results indicate that the most abundant free amino acids are glutamic and aspartic acids and glutamine, which constituted for about 50% of the whole pool. Free methionine and cysteine are absent from both leaves and roots. The highest alkaloid levels occur for all tests during full flowering, the ammonium treated plants containing the most alkaloids.