Distribution of L-DOPA in the root of velvet bean plant (Mucuna pruriens L.) and gravity.

Velvet bean (Mucuna pruriens L.) has been found that the degree of suppression on the lettuce root growth by velvet bean was less on the 3D-clinorotation. The number and growth of adventitious root in velvet bean differed among the clinostated and control group. L-DOPA (L-3,4-dihydroxyphenylalanine) is known to be the major substance in the allelopathy of velvet bean plant, released from its root. Since L-DOPA is a precursor of melanin pigment, and is easily converted to melanin by oxidation, locality of L-DOPA production in the plant body can be seen through pigmentation. The amount of L-DOPA was analyzed by HPLC and LC-ESI/MS. The distribution of L-DOPA in the root was different among the ground control condition and pseudo-microgravity.