Natural Dyestuffs

Pigments and Dyestuffs

Potentialities of Natural Dyestuffs as Antifeedants against Varied Carpet Beetle, Anthrenus verbasci

We studied damage to wool fabrics dyed with different natural and chemical dyestuffs by the larvae of varied carpet beetle, Anthrenus verbasci, as part of a study on the functions of natural dyestuffs. Eight of ten natural dyestuffs showed an antifeeding effect against A. verbasci. Strength of the antifeeding effect of natural dyestuffs in a feeding preference test was in the order lac dye, gal...

The binding of dyestuffs by proteins

Cc . the Action of Dyestuffs on Enzymes

The method of investigation consisted in submitting a preparation of urease to the action of a dyestuff at PHI 7-4 and at 450 for a given time, usually 30 mins. or 1 hour, and in then determining the activity of the enzyme by estimating the amount of ammonia produced at 450 in a given time from a 0 3 % solution of urea. 1 cc. of the enzyme preparation was added to 2 cc. M/15 phosphate buffer so...

The incidence of bladder tumours in a dyestuffs factory.

The incidence of bladder tumours in workers in the dyestuffs industry was first described by Rehn in 1895 and 1906. Leuenberger reported 41 cases in 1912, and by the third decade of this century in Europe exposure to beta naphthylamine and to benzidine had been accepted as a cause of bladder tumours by Kennaway (1924), Berenblum and Bonser (1937), Goldblatt (1949), and Muller (1951). In the U.S...