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Abstract. The biotransformation of [2-14C](--+-)9, 10-dihydrojasmonic acid (DJA) was studied in excised shoots of 6-day-old barley seedlings after 72 h. From the ethyl acetate extract, some minor metabolites were isolated and purified by DEAE-Sephadex A-25 chromatography, thin-layer chromatography (TLC), Cls-cartridges, and high-performance liquid chromatography (HPLC). The structural identification of these metabolites was performed by gas chromatography-mass spectrometry (GC-MS), circular dichroism (CD), and amino acid analysis, and the following amino acid conjugates were found: N-I(-)9,10-dihydrojasmonoyl]valine, N-[( -)9,10-dihydrojasmonoyl]isoleucine, N-J9,10-dihydrojasmonoyl]leucine, N-[11-hydroxy-9,10-dihydrojasmonoyl]valine, N-[ 11-hydroxy-9,10-dihydrojasmonoyl]isoleucine, N-[12-hydroxy-9, 10-dihydrojasmonoyl]isoleucine; and the cucurbic acid-related compounds N-{[3-hydroxy-2(4-hydroxypentyl)-cyclopent-1-yl]-acetyl}isoleucine and N-{[3-hydroxy-2(5-hydroxypentyl)-cyctopent-1-yl]-acetyl}isoleucine. The results suggest conjugation with isoleucine and valine, as well as preferential hydroxylation at position C-11 or hydrogenation at position C-6, as being important steps in the metabolism of (-+)DJA in barley shoots.( -)Jasmonic acid [( -)JA] and its methyl ester (Fig.