Submitted to: Phytochemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 15, 1995
Publication Date: N/A
Interpretive Summary: AAL-toxin has been patented as a herbicide. An analog of AAL-toxin, fumonisin B1 (FB1), is phytotoxic to a number of weeds and crops including susceptible (asc/asc) tomatoes, jimsonweed, black nightshade (BNS) and duckweed. However, FB1 is a mammalian toxin and a possible carcinogen. We tested analogs of AAL-toxin and fumonisins for phytotoxicity to BNS, tomatoes and duckweed and cytotoxicity to mammalian cells. The diester of fumonisin has lower toxicity to mammalian cells and plants. However, no analogs of fumonisins had characteristics that suggest that they could be used as herbicides.
Fumonisin B1 [FB1], AAL-toxin, aminopentols [AP1, hexacetyl AP1 (Ac6AP1), and N-acetyl AP1 (NAcAP1)], and nine analogs (1 thru 9) were tested for toxicity to duckweed (Lemna pausicostata), susceptible tomato (asc/asc) leaf discs, and mammalian cell lines, including dog kidney (MDCK), rat liver hepatoma (H4TG) and mouse fibroblasts (NIH3T3). Analogs 7 and 9 at 10 uM increased cellular leakage and chlorophyll loss from tomato leaf discs. The diester 9 was the most active in the duckweed bioassay, but it was much less toxic to MDCK and H4TG cells with an IC50 of 200 uM compared to 10 uM for FB1. Analog 9 and FB1 showed similar low toxicities (IC50 = 150 uM) to NIH3T3 cells. Among the substances tested analog 9 had the best combination of high phytotoxicity and low mammalian toxicity, but it still did not have sufficiently low mammalian toxicity for consideration as a herbicide.