A novel method for measuring the antioxidant activity using N, N-dimethyl-p-phenylenediamine (DMPD) was developed. The radical cation of this compound gives a stable colored solution and a linear inhibition of color formation can be observed in the presence of 0. 2-11 microg of TROLOX. The experimental protocol, which is rapid and inexpensive, ensures sensitivity and reproducibility in the measure of antioxidant activity of hydrophilic compounds. The effectiveness of the DMPD method on real foods was verified by evaluating the antioxidant ability of wine samples coming from different areas of Campania, Italy. Antioxidant capacity of wines is strictly related to the amount of phenolic compounds. The results obtained by the DMPD method are very similar to those obtained on the same samples when the radical cation of 2, 2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) (Miller et al., 1996) was used.

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Fusarium subglutinans is an important pathogen of maize and other commodities worldwide. We examined MRC-115 and 71 other F. subglutinans strains from various geographic areas for their ability to synthesize fusaproliferin, a novel toxic sesterterpene recently isolated from F. proliferatum. Fusaproliferin production ranged from 30 to 1,500 g/g of dried ground substrate, with 33 strains producing more than 500 g/g. In particular, strain MRC-115 produced as much as 1,100 to 1,300 g/g. In toxicity studies of two invertebrate models, fusaproliferin was toxic to Artemia salina (50% lethal dose, 53.4 M) and to the lepidopteran cell line SF-9 (50% cytotoxic concentration, approximately 70 M, after a 48-h exposure). Fusaproliferin was also toxic to the human nonneoplastic B-lymphocyte cell line IARC/LCL 171 (50% cytotoxic concentration, approximately 55 M in culture in stationary phase after a 48-h exposure). Experiments performed with cells exposed at seeding suggested a possible cytostatic effect at subtoxic concentrations.

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A new toxic sesterterpene, named fusaproliferin, was purified from corn kernel cultures (120 mg/kg dry culture) of a strain of Fusarium proliferatum isolated from corn ear rot in northern Italy. The stain, designated ITEM-1494, also produced fumonisin B1 (1.500 mg/kg dry culture) and beauvericin (90 mg/kg dry culture), but not moniliformin. To monitor toxicity, the brine shrimp assay was used throughout the isolation procedure. Fusaproliferin had a molecular formula of C27H40O5, and it is the first sesterterpene isolated from a Fusarium species.