Phenolic Pigments Research Articles

A preparative method for the isolation of ferulic acid conjugates from wheat leaves.

Abstract Earlier reports1, 2 described the isolation and identification of two abnormal metabolites, N-feruloyl-2-hydroxyputrescine and N-p-coumaroyl-2-hydroxyputrescine, that are present in ethanol extracts of primary leaves of wheat (Triticum aestimum L.) after infection with stem rust (Puccinia graminis f. sp. tritici Eriks. and E. Henn.). These extracts contained numerous other hydroxycinnamic acid derivatives, among them a group of conjugates in much lower concentration that shared some chromatographic and other physical properties with the 2-hydroxyputrescine amides. To isolate these unknown conjugates it was necessary to start from large quantities of source material. Rust-infected flag leaves of field-grown wheat were selected for this purpose. Flag leaves contain much higher amounts of phenolic metabolites and pigments than the primary leaves used previously2 and these interfered with attempts to isolate the unknown conjugates. A new fractionation procedure was therefore developed.

INTRAINDIVIDUAL PHENOLIC VARIATION IN THE GENUS TIARELLA (SAXIFRAGACEAE); ITS GENETIC REGULATION AND APPLICATION TO SYSTEMATICS

SummaryUsing paper chromatography, phenolic pigment profiles were established for each of 160 plants representing three species and various intermediate (“hybrid”) forms of Tiarella (Saxifragaceae). The 160 plants included two collections of 80 plants each, one collection made on July 13, the other on August 10 (1969). All plants were collected during anthesis from a sympatric population.The similarities of pigment profiles were determined by computer programming and were used as measurements of interspecific, intraspecific, and intraindividual variation, the latter represented by phenolic changes which occurred between collection dates. Consideration has been given to various phenomenona which might have induced intraindividual variation and its genetic regulation and application to systematics have been emphasized.

BIOCHEMICAL SYSTEMATICS AND PHYLOGENETIC INTERPRETATIONS IN THE GENUS AQUILEGIA.

The trend in phytosystematic research is toward the elucidation of phylogenetic relationships. In relatively recent years many schematic representations have been designed to show such relationships. Two of the mos!t recent methods for demonstrating natural similarities are The Wagner Divergence Index (Scora, 1967) and the Simlarity Index Method (Similarity Matrix) (Sokal and Sneath, 1963; Sokal, 1966). Concepts from both of these methods of analysis have been employed in the present study to aid in the determination of evolutionary patterns in the genus Aquilegia. Analytical techniques are similar to those used in the Similarity Index Method. The various species have been grouped on the basis of biochemical affinities which may reflect their phylogeny. The characters examined were drawn from a reservoir of polar compounds including flavonoids and other phenolic pigments. Although a few of the flavonoids could be tentatively identified by comparisons of their properties with those of known compounds listed by Harborne (1967) and Geissman (1962), the identity of the large majority of the pigments examined remains unknown. They have merely been assigned a number and characterized by Rf values, absorption spectra, and physical and chemical properties exhibited under U.V. radiation, both with and without test reagents. The similarity index values were derived through computer programming. Both the divergence index method and the similarity index method are Neo-Adansonian, i.e., all characters are given equal weight. Certainly it is absurd to assume that all characters have equal significance in the determination of phylogeny. However, it has been strongly argued by advocates of the Adansonian system that in the absence of an objective method of character weighing a strictly numerical approach eliminates more bias than it induces. It would seem, however, that the applicability of a numerical approach would depend on the heterogeneity of the characters being considered as well as the degree of affinity among the taxa under investigation. Kendrick and Weresub (1966) have shown that the numerical approach haphazardly assembled, equally weighted characters, results in a haphazard classification at least in higher fungi. On the other hand, using the Wagner Divergence Index, Hardin (1957) and Scora (19,66) devised evolutionary patterns, in the genera Aescu,lus and Monarda, respectively, which correlated very well with previously existing concepts and phytogeographical studies. It is felt that a numerical approach is equally applicable to a phylogenetic analysis of the cytogenetically similar species of Aquilegia, especially when dealing with such biogenetically related characters as the various flavonoid pigments.

A phenolic pigment as a hydrogen carrier in D-lactate cytochrome c reductase system of a yeast

A phenolic pigment as a hydrogen carrier in D-lactate cytochrome c reductase system of a yeast Get access KEIJIRO MIYATA, KEIJIRO MIYATA Biological Laboratory, Tokyo Institute of TechnologyTokyo Search for other works by this author on: Oxford Academic Google Scholar MASATERU AOYAMA, MASATERU AOYAMA Biological Laboratory, Tokyo Institute of TechnologyTokyo Search for other works by this author on: Oxford Academic Google Scholar MASASHI NAGAHISA MASASHI NAGAHISA Biological Laboratory, Tokyo Institute of TechnologyTokyo Search for other works by this author on: Oxford Academic Google Scholar Plant and Cell Physiology, Volume 9, Issue 1, 1968, Pages 155–157, https://doi.org/10.1093/oxfordjournals.pcp.a079324 Published: 01 January 1968 Article history Received: 11 November 1967 Published: 01 January 1968

Mangiferin and Other Glycophenolics in Iris Species

A YELLOW phenolic pigment, which appears on paper chromatograms under ultra-violet light as an apricot-coloured or dull-brown spot changing to a fluorescent yellow-green in ammonia, was first recognized as being present in petals of bearded iris cultivars in 1958. It is probably one of the major co-pigments in Iris flowers, producing, by interaction with the anthocyanin (a delphinidin glycoside), a range of purple, mauve and blue shades1. In an earlier survey of leaf material, the same or a similar substance was observed on chromatograms of all species belonging to the section Pogoniris (which includes the bearded cultivars), of I. pseudacorus Fischer in the Laevigata group of the section Apogon, and of I. dichotoma Pallas in the section Pardanthopsis. This pigment differed in its spectral, chromatographic and colour properties from all the commonly occurring phenolics, such as the flavonoids, and has now been identified as the glycoxan-thone, mangiferin (2-glucosyl-1,3,6,7-tetrahydroxyxanthone) (I), by direct comparison with authentic material. Identification was by means of m.p. and mixed m.p. (268°–270°, decomp.); of the ultra-violet spectra (maxima at 242, 258, 316 and 364 mµ, undergoing characteristic bathochromic shifts in the presence of alkali, aluminium chloride, sodium acetate and sodium acetate–boric acid); of the colour reactions and of co-chromatography in eight different solvent systems. The constituent in the leaves of I. pseudacorus has been examined chromatographically and spectrophotometrically, and appears to be identical with that in the bearded iris. The constituent in I. dichotoma has not been examined in detail.

Cytochemical and electron-microscopic investigation of the golgi apparatus and golgi-resembling inclusions in the root meristem ofFagopyrum esculentum moench

1. The classical cytological methods, cytochemistry and electron microscopy were used to study the cytoplasm ofFagopyrum esculentum Moench. 2. Cytochemical investigation of inclusions resembling the Golgi apparatus was possible after fixation in Ca-formaldehyde and embedding in carbowax. 3. A characteristic of the inclusions was drawn up. The inclusions resemble some pigment substances of animal cells cytochemically (lipopigments, phenolic pigments). 4. Conditions of staining inclusions with basic dyes, Sudan black B and the PAS reaction were studied. 5. A functional investigation revealed a cycle resembling that known in the formation of secretions in animal cells. 6. The Golgi apparatus and inclusions resembling it appear under the electron microscope as two distinct components.