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A highly potent attractant of zoospores of Aphanomyces cochlioides, a causal fungus of the root rot disease of spinach (Spinaeia oleracea), was isolated from spinach roots, and its structure was determined by spectroscopic evidence and chemical synthesis as cochliophilin A (5-hydroxy-6,7-methylenedioxyflavone, 1). A chromosorb particle prepared by soaking in solution of 1 showed a potent attracting activity toward the zoospores using concentrations of 1 above 10 -9 or 10 -10 M.

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Two new cuparene-type sesquiterpenes, enokipodins C (1) and D (2), were isolated from culture medium of an edible mushroom, Flammulina velutipes, along with enokipodins A (3) and B (4). The structures of 1 and 2 were determined using spectroscopic methods (HRMS, (1)H and (13)C, and 2D NMR). The absolute configuration of enokipodin C was determined from the observed (1)H NMR chemical shifts and NOEs in NOESY experiments after conversion into the corresponding esters with the chiral reagent 2-(2'-methoxy-1'-naphthyl)-3,4-dichlorobenzoic acid. All the metabolites showed antimicrobial activity against a fungus, Cladosporium herbarum, and Gram-positive bacteria, Bacillus subtilis and Staphylococcus aureus.

Peroxynitrite (ONOO 3 ), a reactive nitrogen species, is capable of nitrating tyrosine residue of proteins. Here we show in vitro evidence that plant phenolic compounds can also be nitrated by an ONOO 3 -independent mechanism. In the presence of NaNO 2 , H 2 O 2 , and horseradish peroxidase (HRP), monophenolic p-coumaric acid (p-CA, 4-hydroxycinnamic acid) was nitrated to form 4-hydroxy-3-nitrocinnamic acid. The reaction was completely inhibited by KCN, an inhibitor for HRP. The antioxidant ascorbate suppressed p-CA nitration and its suppression time depended strongly on ascorbate concentration. We conclude that nitrogen dioxide radical (NO c 2 ), but not ONOO 3 , produced by a guaiacol peroxidase is the intermediate for phytophenolic nitration. ß

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