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Article
Porphyrins and phycobilins in Precambrian rocks
Samples of Precambrian rocks (1.7–2.6 billion years, U.S.S.R.) contain metalloporphyrins and linear tetrapyrrole pigment similar to phycobilin 655 from modern blue-green algae Microcystis (according to data of...
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Article
Metalloporphyrins and molecular complexes of amino acids with porphyrins in juvenile volcanic ash
In samples of juvenile ash of the volcano Tjatja, USSR (that erupted in 1973) metalloporphyrins were found. With respect to the fluorescence spectra free bases of the compounds were close to the pigments that ...
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Article
Molecular complexes of amino acids with porphyrins as possible precursors of pigment-protein systems
The present communication gives experimental results of the studies of catalytic and photochemical properties of peptide-like compounds containing metalloporphyrins (hemoproteinoids and molecular complexes obt...
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Article
Gemoproteinoids as probable sensitizers of prebiological photophosphorylation
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Article
Proteinoid microspheres and the process of prebiological photophosphorylation
A chemical model of prebiological photophosphorylation with participation of hemoproteinoid microspheres, mixed microspheres containing bonded riboflavin and microspheres obtained from glycine rich proteinoids...
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Article
Flavonoids and silicon in certain plant pollen
The flavonoid composition of certain plant pollens is studied. Pollen from representatives of various families differs in the quantitative and qualitative composition of the flavonoid complex. A specially deve...
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Article
Hydroxyanthraquinones and flavonoids of garland chrysanthemum
The stems of the vegetable plant garland chrysanthemum (Chrysanthemum coronarium L.) were shown to contain emodin (in its aglycone and glycoside forms) and chrysophanol. Chrysophanol and chrysazin were isolated f...
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Chapter and Conference Paper
The Nucleotide and Nucleotide-Like Coenzymes in Primitive Metabolism, Photobiology and Evolution
The evolutionary link between hypothetical primordial RNA world [1] and the modern R(D)NA/Protein biosphere can hardly be revealed by only searching for chemical roots of primitive genetic coding. The analysis of...
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Article
Phenolic Substances in Medicinal Plants
Compositions of phenolic substances were studied in the leaves of 21 species of medicinal plants. Flavonoid levels varied from 1.94 to 5.42%, whereas total amounts of monomeric polyphenols and hydroxybenzoic a...
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Article
Pellets of Some Mollusks in the Biogeochemical Flows of C, N, P, Si, and Al
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Article
Forms of Silicon in Medicinal Plants
The contents of three forms of silicon (organic, soluble mineral, and polymeric) were determined in leaves of 21 medicinal plants. At a total content of silicon of 0.74 to 3.59%, the organic, soluble mineral, ...
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Article
Study of Chemical Structure and of Photochemical Activity of Abiogenic Flavin Pigment
A product with molecular mass of 500–550 Da was isolated from a pigmented material formed by thermolysis (185°C) of a mixture of glutamic acid, glycine, and lysine (the optimal molar ratio of 8:3:1). After pur...
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Article
Modeling of abiogenic synthesis of ATP
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Article
Photoactivated matrices in prebiotic evolution processes
The processes of abiogenesis of biologically important compounds (amino acids, peptides, pyruvic acid, etc.) under the conditions of adsorption in mineral (titanium dioxide, silica gel) or organic (melanoidin)...
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Article
Photobiochemistry of folates: A photochemical reduction of folic acid
Exposure of deaerated folic acid solutions containing an electron donor to UV radiation (310–390 nm, I = 0.4 W m−2) induced formation of dihydrofolic acid (DHFA), a photoexcitation which gave tetrahydrofolic acid...
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Article
Characteristics of the accumulation of phenolic compounds in amaranth leaves under the effect of growth stimulators
It is shown that preplanting treatment of seeds and foliar treatment of amaranth plants in the budding stage with amaranth-based biopreparations Amirosel, Albit, and Amir has a positive effect on accumulation ...
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Article
Excited flavin and pterin coenzyme molecules in evolution
Excited flavin and pterin molecules are active in intermolecular energy transfer and in photocatalysis of redox reactions resulting in conservation of free energy. Flavin-containing pigments produced in models...
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Article
Quantitative assessment of feeding in a free-ranging group of Przewalski horses, Equus przewalskii, in a steppe habitat (the Askania Nova Biosphere Reserve)
The daily food intake and digestibility by Przewalskii horses were estimated under conditions of free ranging in the steppe Askania Nova Reserve. The digestibility was determined from the proportions of inert ...
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Article
Photoexcited molecules of pteridine derivatives in prebiotic and biological evolution
In the models of prebiotic processes, flavins and other pteridine derivatives transform light energy into the energy of chemical bonds, including energy-rich bonds of ATP. In the course of biological evolution...
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Article
Abiotic model of photophosphorylation of ADP to ATP: Characteristics of photoreceptor pigments and the role of organosilicate matrix
A model of photophosphorylation of ADP to ATP under UV and blue light with the use of substances available in the prebiotic period of evolution is proposed. It is shown that the photoactive pigments of flavin ...