Ancistrocladaceae and Dioncophyllaceae: Botanically Exciting and Phytochemically Productive Tropical Lianas
1. Key Words:
Palaeotropical plants; Caryophyllidae; Nepenthales; Ancistrocladaceae and Dioncophyllaceae (see also 'Naphthylisoquinoline Alkaloids'); Ancistrocladus, Triphyophyllum; Dioncophyllum; Habropetalum; botanical and morphological characteristics; carnivory; cultivation of plants in the greenhouse (in collaboration with the Botanical Garden of the University of Würzburg); chemotaxonomy; molecular phylogeny and systematic position (in collaboration with Prof. G. Heubl, Institut für Systematische Botanik der LMU München); production of plant cell cultures.
2. Graphical Abstract:
Molecular Phylogeny of Dioncophyllaceae and Ancistrocladaceae within the Nepenthales with Particular Focus on the Carnivorous Taxa Nepenthaceae, Drosophyllaceae, and Droseraceae
Dioncophyllaceae and Ancistrocladaceae (Botanical Characteristics)
3. Brief Description:
The systematic position of the palaeotropical plant families Ancistrocladaceae and Dioncophyllaceae  indigenous to the tropical rain forests of Africa and Southeast Asia, was unclear for a long time. Comparison of DNA sequence data [2,3] have now permitted a reliable placement within the Caryophyllidae sensu lato as a sister clade of the carnivorous Drosophyllaceae, in close vicinity to the likewise carnivorous Nepenthaceae and Droseraceae, along with a second closely related clade combining the Plumbaginaceae, Polygonaceae, Tamaricaceae, and Frankeniaceae (see Figure 1).
Triphyophyllum, a monotypic genus within the Dioncophyllaceae, is also known to produce carnivorous glandular leaves during a certain period of life [4-7]. The name Triphyophyllum is derived from the three different kinds of leaves that this plant can form (see Figure 2): (a) lanceolate juvenile leaves, (b) carnivorous glandular leaves, and (c) hooked adult leaves. In the greenhouse of the Botanical Garden of the University of Würzburg, we have been the first to grow Triphyophyllum peltatum (Hutch. & Dalz.) Airy Shaw to maturity, and have observed its life cycle under controlled conditions until flowering and development of its characteristic ‘gymnosperm’ fruits (see Figure 3) . Besides this rare and difficult-to-cultivate liana, only two other species, Dioncophyllum thollonii Baillon and Habropetalum dawei (Hutch. & Dalz.) Airy Shaw, belong to the small Dioncophyllaceae family.
The related, yet non-carnivorous, monotypic genus Ancistrocladus Wall. (Ancistrocladaceae) comprises about 20 species, and is characterized by a disjunct distribution in the palaeotropics with two areas of speciation, one in tropical West, Central, and East Africa, and one in South East Asia. All taxa are scandent shrubs or woody lianas with tendril-like modified shoots provided with typical circinate woody hooks as climbing devices (see Figure 1g). In the Botanical Garden of Würzburg, currently specimens of more than 12 Ancistrocladaceae species are being cultivated, among them Ancistrocladus heyneanus from India , A. cochinchinensis from Vietnam, A. abbreviatus from Ghana [8,9], and also some probably new Ancistrocladus species from the Congo basin [10,11]. In 1999, we discovered a phytochemically unusual Ancistrocladus species (see Figure 4a) from an isolated mountain of Peninsular Malaysia, which is morphologically, phytochemically, and genetically distinguishable from all other South East Asian species. Based on complete material including all stages of flowering (see Figure 4b-f) and fruits, and in a close cooperation with G. Heubl et al. (LMU München) we provided a botanical description of this new Ancistrocladus species. According to its site of discovery, we named it Ancistrocladus benomensis .
Both plant families, the Ancistrocladaceae and the Dioncophyllaceae, have in common that they are the only known ‘producers’ of the naphthylisoquinoline alkaloids, structurally, biosynthetically, and pharmaceutically unique natural biaryl products (see also ‘Naphthylisoquinoline Alkaloids’).
4. Selected Publications
5. Cooperations and Research Grants:
Plant collection in collaboration with numerous chemists and biologists from tropical countries, among them:
Work on the molecular phylogeny, chemotaxonomy, and systematic position of Dioncophyllaceae and Ancistrocladaceae with Prof. Dr. G. Heubl (Institut für Systematische Botanik der LMU München), sponsored by the Deutsche Forschungsgemeinschaft (DFG) ("Molecular Phylogeny and Chemotaxonomie of the Ancistrocladaceae Plant Family", Individual Grants Br699/7 and Br 699/14-2);
Work on the biosynthetic origin of naphthylisoquinoline alkaloids from Dioncophyllaceae and Ancistrocladaceae plants within a special research project entitled "Biosynthesis of Axially Chiral Alkaloids from Plants" incorporated into the DFG priority programme 1152 "Evolution of Metabolic Diversity", Individual Grant Br 699/9).