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The chemical contituents are concerned in the quality of tomato fruit in respect to color, texture, flavor, nutritive value, and wholesomeness. In general, high sugar contents, redness of color, and firm texture are associated with prominence of rich flavor. Biochemical changes as influenced by growth, maturation, and environment of tomato fruit are discussed.

Let G be the linear group leaving a homogeneous polynomial of degree k fixed. The author shows that either the polynomial is a polynomial in fewer than the assigned number of variables or that the ( k − 1 ) (k - 1) st prolongation of G is 0. The author also shows that this result is optimal.

The composition of tomato fruit at nine different stages of maturity was studied. The dry matter content decreased gradually, whereas the alcohol-soluble material and non-protein nitrogen increased with ripening. Total nitrogen decreased up to the large green stage and then increased during ripening. Starch accumulated until nearly the large green stage and then diminished rapidly. Of the two components of starch, amylose decreased much faster than amylopectin, and the ratios of amylopectin and amylose thus increased during ripening. Among the amino acids, glutamic acid was present in an exceptionally high concentration, and its concentration doubled during ripening. A concomitant decrease in the concentration of several other amino acids was noted. The possibility of amino acids serving as precursors for the synthesis of volatile aroma components in tomato is discussed.

Crude enzyme preparations from fresh tomatoes in the presence of certain amino acids are capable of producing carbonyl compounds. The activities of the enzyme extracts from field-grown tomatoes were generally higher than those grown in greenhouses. Enzyme activities increased with the maturity of the fruit, whereas the protein content of the extracts tended to decrease. Three amino acids used as substrates gave distinctive responses with the enzyme and the activity in general appears to be associated with the insoluble part of the preparations.

An enzyme preparation from fresh tomato fruit catalyzed the degradation of l -leucine. The reaction products were separated as their 2,4-dinitrophenylhydrazones and analyzed by TLC. α-Ketoisocaproic acid, the keto acid corresponding to l -leucine, was identified. The conversion was confirmed by studies with l -leucine-U- 14 C as substrate. Enzyme activity was found to occur predominantly in the supernatant fraction and to decrease with ripening of fruit.

Soybean plants were fumigated with HF or grown in nutrient solution containing sodium fluoride or fluoroacetate, and the organic acid fractions of the leaf extracts were compared. Organic acid extracts from these treatments contained fluoroorganic compounds that were chromatographically similar to fluoroacetate and fluorocitrate. These fractions were separated from HF- and NaF-treated leaf extracts and found to inhibit aconitase prepared from either pig heart or soybean fluorocitrate. Aconitase from soybean leaves was as sensitive to fluorocitrate as that isolated from pig heart. Fluorocitrate was identified in extracts of fluoride-treated plants by infrared spectroscopy.

The conditions for the activation of sugar carbon for the racemization of d -K[Co(EDTA)]. 2H 2 O have been investigated. The activity of the carbon increased with the number of activations and was greatest when the carbon was ignited in air and cooled in N 2 .

The α-alanine aminotransferase, l -alanine:2-oxoglutarate aminotransferase EC 2.6.1.2, has been demonstrated in tomato fruit. The enzyme was found in both the supernatant and the mitochondrial preparations; under the experimental conditions used, activity in the mitochondria decreased with development of fruit. The α-alanine aminotransferase was more active than leucine aminotransferase from the same source.

Fifteen distinct peaks were resolved from red-ripe tomato flavor extract by gas Chromatographic techniques. Except isobutanol, n -hexanol, and n -hexanal, concentrations of the volatile components in the field-grown tomatoes were higher than those in the greenhouse-grown tomatoes. Artificially ripened tomatoes contained less volatile components.

The composition of tomato fruit at nine different maturity stages was studied. The dry matter content decreased gradually, whereas the alcohol soluble material and non-protein nitrogen increased with ripening. Total nitrogen decreased up to the large green stage and then increased during ripening. Starch accumulated until nearly the large green stage and then diminished rapidly. Of the two components of starch, amylose decreased much faster than amylopectin, and the ratios of amylopectin and amylose thus increased during ripening. Among the amino acids, glutamic acid was presented in an exceptionally high concentration, and its concentration doubled as the fruit ripened. A concomitant decrease in the concentration of several other amino acids was also noted. The possibility of amino acids serving as precursors for the synthesis of volatile aroma components in tomato is discussed. Evidence is then presented to demonstrate that crude enzyme preparations from fresh tomatoes can produce carbonyl compounds in the presence of some amino acids. The enzymatic activities of the preparations from field-grown tomatoes were generally higher in converting alanine and leucine than those of the preparations from greenhouse-grown tomatoes. Preparations from young fruit had lower activity despite the high protein concentration. The activity of the enzyme extracts increased with development stages of the fruit, and different amino acids showed different patterns in the response to enzyme preparations. The enzymes are sensitive to pH changes and there is a marked difference in activity between the soluble and the insoluble fractions of the extracts. Analyses were subsequently carried out by gas chromatography for the volatile components enzymatically produced from amino acids by tomato extracts. Alanine, leucine, and valine were found to be the most important precursors. Chromatograms differed with enzyme preparations and with substrate amino acids used. More volatile components were produced with enzymes prepared from red-ripe tomatoes than with those from green tomatoes. The enzyme preparations from greenhouse - grown ripe tomatoes were found capable of producing 3-methyl-butanal in the presence of L-leucine. The produciton of 3-methylbutanal was further confirmed using (14C)-L-leucine as substrate. When preparations from young green tomatoes were used, the enzymatic reaction products contained propanal. This indicates that different enzyme preparations varied their activity in converting the same substrate amino acid. Further experiments have shown that the enzyme extracts from field-grown red ripe tomatoes produced propanal and some unidentified carbonyl compounds from alanine, whereas they produced several alcohols from leucine and valine. Addition of two amino acids as substrates sometimes resulted in new volatile components. The production of volatile components from amino acids appears to involve transamination. This was demonstrated by the analysis of glutamic acid formed during the enzymatic reactions. A decrease in the substrate amino acid and a concomitant increase in glutamic acid was observed in the reaction mixtures. Based upon the reaction products that were identified, some hypothetical pathways of the biosynthesis of a few volatile components have been suggested.

Presents a simplified system for representing close-packed structures and applies it to crystalline structures of the elements.