|SHIER, THOMAS - University Of Minnesota|
|YOSHIZAWA, TAKUMI - Ehime University|
Submitted to: Toxicon
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/30/2013
Publication Date: 7/26/2013
Citation: Abbas, H.K., Shier, T.W., Yoshizawa, T. 2013. Cytotoxicity and Phytotoxicity of Trichothecene Mycotoxins Produced by Fusarium spp. Toxicon. 74(2013):68-75.
Interpretive Summary: Twenty-eight simple trichothecene mycotoxins isolated from the mold Fusarium spp. were tested in vitro for toxicity to a higher plant (duckweed, Lemna pausicostata), and four mammalian cell lines. An examination of structure-activity relationships within the collection indicated that two types of structural features were associated with high phytotoxicity and lack of observed mammalian cytotoxicity: (i) highly acetylated derivatives and (ii) de-epoxy-unacetylated derivatives. Additional research is needed to determine if these if these trichothecene derivatives retain differential toxicity in vivo, and if derivatives can be found that possess acceptable environmental stability.
Technical Abstract: Trichothecenes, a major class of mycotoxins produced by Fusarium, Myrothecium, and Stachybotrys species, are toxic to plants, causing blights, wilts and other economically-important plant diseases, and to mammals, for example feed-refusal caused by deoxynivalenol (vomitoxin). Macrocyclic trichothecenes are generally more toxic than simple trichothecenes, which are sub-divided into type A (e.g., T-2 toxin) and type B (e.g., deoxynivalenol). In this study 28 simple trichothecenes were examined for potential application as bioherbicides, which requires high phytotoxicity with low mammalian toxicity. The study used a small aquatic plant, Lemna pausicostata, to estimate phytotoxicity and four cultured mammalian cell lines to estimate mammalian toxicity. Various structure-activity relationships were identified among structural analog series occurring in the sample pool. Among the structure-activity relationships relevant to bioherbicide development were observations that peracetylation of type B trichothecenes, including deoxynivalenol, and de-epoxidation of type A trichothecenes both substantially reduced mammalian toxicity with little effect on phytotoxicity.