Planta Med 2019; 85(09/10): 774-780
DOI: 10.1055/a-0895-5753
Natural Product Chemistry and Analytical Studies
Original Papers
Georg Thieme Verlag KG Stuttgart · New York

Types A and D Trichothecene Mycotoxins from the Fungus Myrothecium roridum

Waranya Lakornwong
1  Natural Products Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
,
Kwanjai Kanokmedhakul
1  Natural Products Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
,
Kasem Soytong
2  Department of Plant Production Technology, Faculty of Agricultural Technology, King Mongkutʼs Institute of Technology Ladkrabang, Bangkok, Thailand
,
Arm Unartngam
3  Bioproduct Science, Department of Science, Faculty of Liberal Arts and Science, Kasetsart University Kamphaeng Saen Campus, Nakorn Pathom, Thailand
,
Sarawut Tontapha
4  Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
,
Vittaya Amornkitbamrung
4  Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
,
Somdej Kanokmedhakul
1  Natural Products Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
› Author Affiliations
Further Information

Publication History

received 01 October 2018
revised 25 March 2019

accepted 10 April 2019

Publication Date:
26 April 2019 (eFirst)

Abstract

Chromatographic separation of extracts from the fungal biomass of a plant pathogenic fungus, Myrothecium roridum, yielded 8 trichothecene toxins including 6 type D trichothecenes (16) and 2 type A trichothecenes (78). 6′,12′-Epoxymyrotoxin A (1) and 7′-hydroxymytoxin B (2) were new macrocyclic trichothecenes, while the other trichothecenes were identified as myrotoxin B (3), myrotoxin D hydrate (4), 2′,3′-epoxymyrothecine A (5), miotoxin A (6), and 2 trichothecenes lacking the macrocyclic lactone system, roridin L-2 (7) and trichoverritone (8). The structures of these mycotoxins were characterized using spectroscopic methods. The absolute configurations of 1 and 2 were determined by NOESY and a comparison of their experimental and calculated ECD spectra. Most of these mycotoxins (14 and 6) exhibited highly potent antimalarial activity against Plasmodium falciparum. They also showed strong cytotoxicity towards KB and NCI-H187 cell lines (IC50 0.60 – 112.28 nM), as well as the Vero cell line (IC50 1.50 – 46.51 nM).

Supporting Information