抄録
The comparative studiets have been m, ade as to the tyrosinase activity, tyrosine, phenolic substances in the blood and integumenf. making use of sdm, e m, arking m, utants to ascertain the differences of melanin formation in the silkworm larvae. The investigation has been carried out from the 4-tn instar laryal stage to the pupal ones used the strains of Striped (p), Zebra (Ze), Moricaud(pM), Multilular (L), dilute black (bd) and lemon yellow (lem) comparing with ndrm, al (p or +P) segregated from the same batches. Warburg/s manom, eter was used for the measurement of tyrosinase activity making use of Brenzcatechin and p-Cresol as the substrates . The tyrosinase activities in the integum, ents of ps, p, i, Ze and bd were higher than normal . at before and during the m.o.ulting periods, and also ps showed higher level of tyrosinase concentration than norm, al at the 5 th age, but no sighificant difference was observed between L, Iem, and norm, al . On the other hand we could hardly recognize the differences of tyrosinase activity in the blood in all the strains at every stages. ' The tyrosinase activity of the integurri!, eht of black pigmental region was higher than that of nohe pi-g:nental one in Zebra m, arking during the rooultina period; but its. differe.nce was not clear at the 5 th age. Tyrosine and som, e phenolic substances were nea-sured making use of the above lrentioned strains by the reaction of Millon, 'xanthoprotei, n, am, m, oniacal silver nitrate, ferric chloride reactions. As for the aminoacids, the discrim, ination by paper partition chro-m, atography was adopted . No differences of the quantity of chromogen have been recognized between the norm, al and marking individuals in the blood and integunent. From these results we can conclude that one of the factor determ, ining the difference of the formation of marking pign), ent is the difference of tyrosinase activity in the integumnt befote and duririg the moulting period.
