We studied the developmental changes in photosynthetic and respiration rates and thermal dissipation processes connected with chloroplasts and mitochondria activity in etiolated wheat (Triticum aestivum L., var. Irgina) seedlings during the greening process. Etioplasts gradually developed into mature chloroplasts under continuous light [190 µmol(photon) m -2 s -1 ] for 48 h in 5-day-dark-grown seedlings. The net photosynthetic rate of irradiated leaves became positive after 6 h of illumination and increased further. The first two hours of de-etiolation were characterized by low values of maximum (F v /F m ) and actual photochemical efficiency of photosystem II (PSII) and by a coefficient of photochemical quenching in leaves. F v /F m reached 0.8 by the end of 24 h-light period. During greening, energydependent component of nonphotochemical quenching of chlorophyll fluorescence, violaxanthin cycle (VXC) operation, and lipoperoxidation activity changed in a similar way. Values of these parameters were the highest at the later phase of de-etiolation (4-12 h of illumination). The respiration rate increased significantly after 2 h of greening and it was the highest after 4-6 h of illumination. It was caused by an increase in alternative respiration (AP) capacity. The strong, positive linear correlation was revealed between AP capacity and heat production in greening tissues. These results indicated that VXC in chloroplasts and AP in mitochondria were intensified as energy-dissipating systems at the later stage of greening (after 4 h), when most of prolamellar bodies converted into thylakoids, and they showed the greatest activity until the photosynthetic machinery was almost completely developed.

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A series of terpenophenol-chlorin conjugates where terpenophenolic fragment has amide bond with macrocycle of methylpheophorbide a, formed by amidation of 13(2)-ester group were obtained by interaction of methylpheophorbide a and ortho-aminomethyl derivatives of 2-isobornyl-4-methylphenol. The substances investigated ability to interact with the cell membrane was shown in blood erythrocytes surface structure with scanning electron microscope. The conjugates studied were established to have antioxidant and membrane protective properties resulted from inhibiting H2O2-induced erythrocytes hemolysis and decrease of lipid peroxidation secondary product accumulation.

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