SUMMARY: Volatiles of peach (Prunus persica L., cultivar, Gleason Early Elberta) fruit were studied by gas‐liquid chromatography, thin‐layer chromatography and infrared spectrometry. Chromatograms of the volatiles of hard‐mature, firm‐mature, soft‐mature, tree‐ripe and artificially ripened, hard‐mature fruit were obtained with temperature programing and flame ionization detection. The volatile concentrates of tree‐ripe peaches produced 86 peaks. The major peaks were isolated and the infrared spectra determined and compared with authentic compounds. In general, concentrations of volatile components increased with advancing maturity. The main volatile components were identified as gamma‐ and delta‐lactones, esters, aldehydes, benzyl alcohol and d‐limonene. The highest total lactone concentration occurred in tree‐ripe peaches and was more than four times that of firm‐mature fruit. Gamma‐decalactone predominated among the lactones in tree‐ripe peaches. Artificially ripened peaches had very small amounts of gamma‐decalactone and lacked gamma‐ and delta‐dodecalactone, with a total lactone concentration abouf one‐fifth that of free‐ripe fruit. Concentrations of esters in artificially ripened fruit reached only one‐third to one‐half those of tree‐ripe peaches. Benzaldehyde was the predominant volatile in tree‐ripe peaches and occurred in five times the concentration found in artificially ripened fruit. These may be the determining factors relative to the inferiority of artificially ripened as compared to free‐ripened fruits.

SUMMARY The biosynthesis of nonvolatile compounds by tomato fruit parallels the growth rate of the fruit, regardless of varieties studied. Volatile reducing substances (VRS, mμ100 g), reducing sugars (percent), water‐soluble pectins (percent), and organic acids (mg/100 g) progressively increase in quantity with advancing maturity. Total titratable acidity (percent) and total pectic materials (percent) increased during the initial stages of maturation, but gradually decreased as the fruit ripened. Ascorbic acid (mg/100 g) increased with the maturity of fruit but declined slightly in the later (red and red‐ripe) stages of maturation. Concentrations of compounds (chlorophylls, mg/100 g; carotene and lycopene, mg/100 g) contributing to the coloration changed significantly as the fruit passed through various degrees of maturation. The pattern of physiological and chemical changes during the development of tomato fruit was nearly identical in both varieties studied. However, V. R. Moscow fruit contained higher amounts of pigments, reducing sugars, pectins, organic acids, ascorbic acid, and VRS than the fruit of Fireball variety, regardless of maturities studied.

Nerve growth factor (NGF) is a protein highly expressed in the male mouse submandibular gland. We have applied a non-radioactive in situ hybridization method using digoxigenin-labeled NGF oligonucleotides, and have found the highest amounts of NGF mRNA in the secretory striated ducts of the male mouse submandibular gland. Scattered strongly positive cells were found in male mouse sublingual glands. Weakly labeled cells were seen in female mouse and in male rat submandibular gland striated duct cells. Using 33P as an alternative to 32P and 35S, we demonstrated a 1.3 KB NGF mRNA in salivary glands of male mice by Northern blot hybridization. Using 33P we detected NGF mRNA in male mouse submandibular glands by in situ hybridization but with a signal that, compared with the non-radioactive method, had a very low resolution. Castration of male mice almost abolished both the 1.3 KB NGF mRNA seen with Northern blots and the NGF mRNA labeling in submandibular glands 4 weeks after the operation, whereas levels were increased 6 hr and 2 days after sympathectomy. We conclude that hybridization with digoxigenin-labeled NGF oligonucleotides is a good tool to study the expression and regulation of NGF mRNA in male mouse submandibular glands.

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