Red-colored Product Research Articles

Histochemistry and identification of flavanols in Verticillium wilt-resistant and -susceptible cottons

The flavanols catechin (3,5,7,3′,4′-pentahydroxyflavan) and gallocatechin (3,5,7,3′,4′,5′-hexahydroxyflavan) were the major precursors of condensed proanthocyanidins in the stem steles of healthy and V. dahliae-inoculated Verticillium wilt-resistant Seabrook Sea Island (SBSI) and -susceptible Rowden cottons. Histochemical studies of the flavanols in noninfected and infected plants were conducted at daily intervals for 4 days after stem-inoculation of 10-leaf-stage plants. The dimethoxybenzaldehyde (DMB) histochemical reagent revealed the presence of the flavanols (catechin, gallocatechin, and their condensed proanthocyanidins) as red-colored products. In non-infected stem steles of both cultivars the flavanols were sparsely distributed in solitary ray, axial and pith parenchyma cells. Greater frequencies of flavanol-containing cells in diseased than healthy stems were first noted in ray parenchyma at 2 and 3 days after inoculation of SBSI and Rowden, respectively. This apparently infection-induced synthesis, much more intense in SBSI than in Rowden, intensified progressively at 3 to 4 days after inoculation, and became evident in the pith adjacent to infected xylem vessels and in a diffuse band in ray and axial parenchyma between the cambium and newly formed xylem vessels. Fungitoxic flavanols in both SBSI and Rowden may create a toxic environment throughout the stem stele which confines V. dahliae to the vessel lumens.

ChemInform Abstract: CHLORPROMAZINE HYDROCHLORIDE AS A SPECTROPHOTOMETRIC REAGENT FOR OSMIUM(VIII) AND OSMIUM(VI)

AbstractDas Titelreagenz bildet in perchlorsaurem Medium mit 0s(VIII) oder Os(VI) ein rotes Radikalkation (530 nm, Gültigkeitsbereich des Beerschen Gesetzes 0.08‐ 7.2 ppm für 0s(VIII) und 0.04‐8.6 ppm für Os(VI)).

ChemInform Abstract: RAPID SPECTROPHOTOMETRIC DETERMINATION OF CERIUM(IV), ARSENIC(III) AND NITRITE WITH PROMETHAZINE HYDROCHLORIDE

AbstractDie Methode beruht auf der Bildung eines roten Produktes zwischen Ce(IV) und dem Reagenz in 3.9‐5.3M H3PO4‐Lösung (518 nm, 1.006·104 Liter mol‐1cm‐1, Gültigkeitsbereich des Beerschen Gesetzes 0.4 bis 15.6 ppm Ce(IV)).

Genetical studies inCajanus cajan (L.) Millsp.

From three sets of crosses involving the phenotypes chocolate, red oxide, green with chocolate streaks and green with red oxide streaks, the action of the genes governing the phenotypes of the pods ofCajanus cajan (L.) Millsp. has been proposed. GeneL controls production of chocolate colour,L (r) an allelomorph ofL hitherto unreported, controls production of red oxide colour and geneD controls distribution of this colour. As regards inheritance of these two genes, the relationships betweenL andL (r) isL>L (r) andD is incompletely dominant overd. The genotypes of the different phenotypes have been presented.

Certain saprophytic mycobacteria from soil sources forming a red color product from PAS.

Certain saprophytic mycobacteria from soil sources forming a red color product from PAS.

THE CHEMICAL ESTIMATION OF TYROSINE AND TYRAMINE

SUMMARY 1. 1-Nitroso-2-naphthol reacts with both tyrosine and tyramine to form a red-colored product which gradually changes to a stable yellow chromo- phore. 2. The yellow compound obtained by treating tyramine with nitroso- naphthol has been isolated. Analysis indicates it to be the product of combination of 1 mole equivalent of each with the loss of 1 mole of water. 3. This reaction has been applied to the determination of tyrosine and tyramine in tissues and to the determination of tyrosine in protein hy- drolysates. 4. New determinations of the tyrosine content of bovine serum albumin and of lysozyme are reported. BIBLIOGRAPHY 1. Gerngross, O., Voss, K., and Herfelt, T., Ber. chem. Ges., 66, 435 (1933). 2. Thomas, L. E., Arch. Biochem., 6, 175 (1944). 3. Giral, J., An. inst. invest. cient. Univ. Nuevo Le6n, 1, 115 (1944). 4. Snell, F. D., and Snell, C. T., Calorimetric methods of analysis, New York, 200 (1937). 5. Block, R. J., and Bolling, D., The amino acid composition of proteins and foods, 2nd edition, Springfield, 114 (1951). 6. Folin, O., and Ciocalteu, V., J. Biol. Chem., 73, 627 (1927). 7. Bernhart, F. W., and Schneider, R. W., Am. J. Med. SC., 205, 636 (1943). 8. Stein, W. H., and Moore, S., Cold Spring Harbor Symposia Quant. Biol., 14, 179 (1949). 9. Shemin, D., J. Biol. Chem., 169, 439 (1945). 10. Velick, S. F., and Ronzoni, E., J. Biol. Chem., 173, 627 (1948). 11. Gunness, M., Dwyer, I. M., and Stokes, J. L., J. Biol. Chem., 163, 159 (1946). 12. Fromageot, C., Cold Spring Harbor