Planta Med 2019; 85(02): 160-168
DOI: 10.1055/a-0752-0295
Natural Product Chemistry and Analytical Studies
Original Papers
Georg Thieme Verlag KG Stuttgart · New York

Infraspecific Variation of Huperzine A and B in Icelandic Huperzia selago Complex

Maonian Xu
1  Faculty of Pharmaceutical Sciences, University of Iceland, Reykjavik, Iceland
,
Starri Heidmarsson
2  Akureyri Division, Icelandic Institute of Natural History, Akureyri, Iceland
,
Margret Thorsteinsdottir
1  Faculty of Pharmaceutical Sciences, University of Iceland, Reykjavik, Iceland
,
Pawel Wasowicz
2  Akureyri Division, Icelandic Institute of Natural History, Akureyri, Iceland
,
Hang Sun
3  Key Laboratory for Plant Biodiversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
,
Tao Deng
3  Key Laboratory for Plant Biodiversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
,
Sesselja Omarsdottir
1  Faculty of Pharmaceutical Sciences, University of Iceland, Reykjavik, Iceland
,
Elin Soffia Olafsdottir
1  Faculty of Pharmaceutical Sciences, University of Iceland, Reykjavik, Iceland
› Author Affiliations
Further Information

Publication History

received 15 February 2018
revised 24 July 2018

accepted 24 September 2018

Publication Date:
05 October 2018 (online)

Abstract

The alkaloids huperzine A and huperzine B were originally isolated from the Chinese club moss Huperzia serrata. They are known inhibitors of acetylcholinesterase, and especially huperzine A shows pharmaceutical potential for the treatment of Alzheimerʼs disease. Its supply heavily relies on natural plant sources belonging to the genus Huperzia, which shows considerable interspecific huperzine A variations. Furthermore, taxonomic controversy remains in this genus, particularly in the Huperzia selago group. With focus on Icelandic H. selago taxa, we aimed to explore the relatedness of Huperzia species using multi-locus phylogenetic analysis, and to investigate correlations between huperzine A contents, morphotypes, and genotypes. Phylogenetic analysis was performed with five chloroplastic loci (the intergenic spacer between the photosystem II protein D1 gene and the tRNA-His gene, maturase K, ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit, tRNA-Leu, and the intergenic spacer region between tRNA-Leu and tRNA-Phe). Huperzine A and huperzine B contents were determined using an HPLC-UV method. The phylogenetic analysis suggests that previously proposed Huperzia appressa and Huperzia arctica should not be considered species, but rather subspecies of H. selago. Three genotypes of Icelandic H. selago were identified and presented in a haplotype networking diagram. A significantly (p < 0.05) higher amount of huperzine A was found in H. selago genotype 3 (264 – 679 µg/g) than genotype 1 (20 – 180 µg/g), where the former shows a typical green and reflexed “selago” morphotype. The huperzine A content in genotype 3 is comparable to Chinese H. serrata and a good alternative huperzine A source. Genotype 2 contains multiple morphotypes with a broad huperzine A content (113 – 599 µg/g). The content of huperzine B in Icelandic taxa (6 – 13 µg/g) is much lower than that in Chinese H. serrata (79 – 207 µg/g).

Supporting Information