Lecithinized superoxide dismutase composition and a process for its production

A lecithinized superoxide dismutase composition containing a lecithinized superoxide dismutase obtained by substituting at least one amino group in copper- and/or zinc-coordinated human superoxide dismutase having a hydroxyethylthio group instead of the mercapto group in cysteine at the position 111, with at least one lecithin moiety represented by the following formula (I):

• [wherein R is a C8-30 alkyl group, and n is an integer of from 2 to 10], wherein the lecithinized superoxide dismutase comprises a lecithinized superoxide dismutase (A) having an m number of amino groups substituted with the lecithin moieties [wherein m is an integer of from 1 to 4 and averages from 1.5 to 2.4] as a main component, and the lecithinized superoxide dismutase (A) consists of from 25 to 40 mol % of a lecithinized superoxide dismutase (a1) wherein m=1, from 35 to 50 mol % of a lecithinized superoxide dismutase (a2) wherein m=2, from 10 to 20 mol % of a lecithinized superoxide dismutase (a3) wherein m=3 and from 5 to 15 mol % of a lecithinized superoxide dismutase (a4) wherein m=4.