Anthocyanin formation

Ishikura, N. (1976). Seasonal changes in contents of phenolic compounds and sugar in Rhus, Euonymus and Acer leaves with special reference to anthocyanin formation in autumn. Botanical Magazine, Tokyo 89 251-257. 

MALDI-TOF-MS has been used to identify and quantify other anthocyanins in foods.When the anthocyanin content of highbush blueberries at different stages of anthocyanin formation were analyzed by both HPLC and MALDI-TOF-MS, it was found that both techniques provided comparable quantitative anthocyanin profiles. While HPLC could distinguish anthocyanin isomers, MALDI-TOF-MS proved to be more rapid. MALDI-TOF-MS has also been used to identify the isoflavones in soy samples. In a comparison of several matrices, 2, 4, 6 -trihydroxyacetophenone (THAP) and 2,5-dihydroxybenzoic acid... 

Oelmiiller R, Mohr H. 1985. Mode of co-action between blue/UV light and light absorbed by phytochrome in light-mediated anthocyanin formation in the milo (Sorghum vulgare Pers.) seedling, Proc Natl Acad Sci USA 82 6124-6128. 

Saure MC. 1990. External control of anthocyanin formation in apple. Sci Hort 42 181— 218. 

Nitrogen source is also very important for plant cell metabolite formation, as reported in suspension cultures of Holarrhena antidysenterica for accumulation of alkaloids [36], in cell suspensions of Vitis vinifera for anthocyanin formation [37], and in shikonin production by Lithospermum erythrorhizon cell cultures [38]. 

After treatment, within 48 hours, there is a cessation of growth. Nodes and buds become necrotic. Young leaves show chlorosis, then necrosis, followed by older leaves which show pigment colour changes (anthocyanin formation). Death of the weeds usually occurs after three weeks. 

Although phenylalanine alone was able to alleviate glyphosate inhibition of anthocyanin formation, feeding tyrosine in addition to phenylalanine was required to achieve partial alleviation of the inhibition of chlorophyll formation. Additional tryptophan did not further increase the chlorophyll content of cotyledons. Further work with buckwheat indicated that a 24-h light or dark incubation of untreated excised hypocotyls had little effect on endogenous shikimate content... 

Inhibition of PAL-activity in vivo should result in the reduced accumulation of metabolites derived from cinnamic acid. Light-induced anthocyanin formation was used as an indicator of the in vivo production of cinnamic acid, as the anthocyanin content of a tissue can be determined by rapid and simple procedures. All compounds tested reduced the production of anthooyanins in isolated hypocotyls incubated in the light, but in these experiments a-NAA showed a nearly tenfold higher inhibitory activity as compared with B-KAA. This result clearly indicates that the action of auxins on anthocyanins exists, but is not very specific. 

Phases of susceptibility in which secondary metabolism is influenced by appropriate signals have also been detected in higher plants. The induction of antho-cyanin biosynthesis (D 22.3.3) by phytochrome in the epidermal cells of the cotyledons of Sinapis alba for instance, first begins 27 h after sowing, despite the fact that the phytochrome system per se is fully functional immediately after sowing. Competence with respect to anthocyanin formation is determined endogenously, i.e., by the state of differentiation of the epidermis cells in which the anthocyanins are formed and accumulated. 

Cyanidin is the most common anthocyanin in foods. In addition, anthocyanins are stabilized by the formation of complexes with other flavonoids (co-pigmentation). In the United States, the daily anthocyanin consumption is estimated at about 200 mg. Several promising studies have reported that consumption of anthocyanin-rich foods is associated with reductions of the risks of cancers - and atherosclerosis and with preventive effects against age-related neuronal and behavioral declines. These beneficial effects of anthocyanins might be related to their reported biological actions such as modulators of immune response and as antioxidants. Knowledge of anthocyanin bioavailability and metabolism is thus essential to better understand their positive health effects. 

Anthocyanins were decolorized at pH 3.0 by the addition of sodinm sulfite at the C-2 or C-4 of the chromophore, a reaction that was rapidly reversible on acidification. Snlfnr dioxide, EDTA, and a combination of snlfnr dioxide and EDTA exerted very small effects on the losses of anthocyanins in strawberry pnrees and juices during 10 wk of storage at -20°C. Conversely, the addition of snlfnr dioxide and storage at 20°C slowed the anthocyanin losses and concnrrently decreased the formation of polymeric componnds, especially in pnrees. EDTA had a slight effect on color stability. ... 

Schwarz, M., Wabnitz, T.C., and Winterhalter, R, Pathway leading to the formation of anthocyanin-vinylphenol adducts and related pigments in red wines, J. Agric. Food Chem., 51, 3682, 2003. 

Lu, Y. and Foo, L.Y.,Unusual anthocyanin reaction with acetone leading to pyranoan-thocyanin formation. Tetrahedron Lett., 42, 1371, 2001. 

Yamada, T., Komiya, T., and Akaki, M., Formation of an inclusion complex of anthocyanin with cyclodextrin, A,gric. Biol. Chem., 44, 1411, 1980. 

Asen, S., Eactors affecting formation of anthocyanin-flavonol co-pigment complexes and their importance on flower color. Plant Physiol, 47, 20, 1971. 

Chen, L.J. and Hrazdina, G., Structural aspects of anthocyanin-flavonoid complex formation and its role in plant color. Phytochemistry, 20, 297, 1981. 

Duenas, M., Fulcrand, H., and Cheynier, V., Formation of anthocyanin-flavanol adducts in model solutions. Anal. Chem. Acta, 563, 15, 2006. 

An anthocyanin occurs in solution as a mixture of different secondary structures, a quinonoidal base, a carbinol pseudobase, and a chalcone pseudobase. ° hi addition, different mechanisms for the stabilization of anthocyanins lead to the formation of tertiary structures such as self-association, inter-, and intra-molecular co-pigmentation. ... 

Anthocyanins can form complexes with metal ions such as tin, iron and aluminium. The formation of a complex, as expected, alters the colour, usually from red to blue. Complex formation can be minimised by adding a chelating agent such as citrate ions. Another problem with anthocyanins is the formation of complexes with proteins. This can lead to precipitation in extreme cases. This problem is normally minimised by careful selection of the anthocyanin. 

---