Soluble peroxidase activity increased dramatically during the early stages .of tomato fruit development, reaching a maximum at the mature-green stage. Ionically and covalently bound peroxidases were also observed, and the activities of these fractions increased steadily throughout fruit development. IAA (indoleacetic acid) oxidasc activity was observed in both soluble and bound fractions and paralleled the peroxidase activity. Tissue homogenates from juvenile fruit caused an extended induction period in IAA oxidation reactions catalyzed by the purified tomato fruit peroxidase, suggesting the occurence of a high concentration of phenolic-type auxin protectors in this tissue. As the fruit developed, tissue homogenates showed a reduction in the amount of auxin protectors as the IAA oxidizing capacity of the fruit increased.

Red light induced and far red light inhibited carotenoid biosynthesis in ripening tomatoes (Lycopersicon escuientum Mill.) when compared to controls kept in the dark. Red illumination following far red illumination reversed the inhibitory action of far red light on carotenoid biosynthesis, suggesting a phytochrome-mediated process. Quantitation of individual carotenoids favored the hypothesis of two separate carotenoid biosynthetic pathways in tomatoes.Piringer and Heinze (9) have shown that the synthesis of a flavonoid pigment was promoted by red illumination and inhibited by far red illumination in the cuticle of tomatoes. Khudairi and Aboleda (7) proposed that lycopene biosynthesis in tomatoes was phytochrome-mediated and was related to plant hormones. Jen (6) used spectral lights and showed that red light enhanced carotenoid formation in tomatoes more than white or green lights. Thomas and Jen (12) demonstrated that the amount of carotenoids synthesized in ripening tomatoes was proportional to the logarithm of red light intensity up to a saturation point, a phenomenon associated with the phytochrome-mediated response in plants (8).In this communication, the effects on carotenoid biosynthesis in tomatoes by red and far red illumination were investigated, and the carotenoid composition of the treated fruit was analyzed.

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Assay of tannase activity was performed directly, using extracts of black tea leaf, by a pH stat method at the pH optimum of the enzyme (6.0). Reaction rates were calculated from the initial rates of the volume of titrant vs. time plots, and activity was expressed as pmoles/min. The enzyme was unstable to pH levels above 6.0 and temperatures above 40°C. Optimum temperature was 35°C. Using saturating amounts of enzyme, the pH stat was also used to determine total hydrolyzable gallate for kinetic studies and to determine the effect of gallated polyphenols on loss of solids in instant tea processing.