[New intermediate reactions in the process of protochlorophyllide photoreduction]

It has been found that formation of non-fluorescine intermediate product with the absorption maximum 690 nm during photochemical hydration of protochlorophyllide in ethiolated plant leaves can also proceed at -196 degrees C. During dark transformation of this product two forms of the pigment with the fluorescence maxima 695 and 685 nm are initiated, the first one preceding. The dependence of the spectral changes discovered on the light spectral composition is interpreted as a consequence of switching on of the parallel reactions of precursors or as a result of photoreversible reaction into chlorophill biosynthesis.