Time dependent changes were studied in adult rats fed a protein free diet for 87 days. Measures were obtained on: liver, intestine, carcass and muscle protein; carcass collagen; A/G ratio and hemoglobin concentration in blood; urinary hydroxyproline and N^r-methylhistidine.
(1) At the early stage of protein-depletion, proteins of the liver and intestine decreased rapidly, but at a later stage the decrease was very slow. A/G ratio and hemoglobin concentration in blood showed similar trends. On the Contrary, muscle protein and collagen were lost continuously to the last day of the protein-depletion. These findings indicate that in the early stage of protein-depletion liver, intestine and blood proteins were utilized in the amino acid pool for protein biosynthesis, but at a later stage muscle protein and collagen were mainly utilized.
(2) At 64 days of protein-free diet, 56% and 20% of carcass protein loss resulted from muscle protein and collagen, respectively. Therefore, collagen is probably one of the main sources of the amino acid pool for protein biosynthesis in protein-depletion rats.

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A porous polymer, Porapak Q, was used as packing material to concentrate trace amounts of volatile sulfur compounds in beer. Hydrogen sulfide (H₂S), dimethyl sulfide (DMS), methyl mercaptan (MeSH), ethyl mercaptan (EtSH) and other volatile agents in the concentrate were analyzed by gas chromatography with a flame photomeric detector (FPD-GC). This newly developed technique enabled quantitative determinations of MeSH and EtSH in wort and beer. MeSH was present at levels as high as 2_??_4 μg/liter in hopped worts but rapidly decreased to 0.1_??_0.2 μg/liter in 2_??_3 days after yeast pitching and then increased gradually to 0.6_??_0.8 μg/liter by the end of primary fermentation. Beer MeSH content changed little during the lagering period. EtSH, on the other hand, was entirely absent in hopped worts, but emerged during fermentation, reaching a maximum level (0.3_??_0.7 μg/liter) at the 6_??_7 days of main fermentation, and then decreased during lagering to 0.1 μg/liter or less. After bottling, EtSH disappeared rapidly, while MeSH persisted in bottled beer and increased gradually with storage time at higher temperature (45°_??_60°C).

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The purpose of the study was to investigate the major components that contribute to the sulfury and yeasty flavor of beer. Volatile sulfur compounds were extracted from beer with dichloromethane or ethyl acetate and subjected to gas chromatographic analysis (FPD-GC) and GC-mass spectrometry. Dichloromethane extracts of lager beer usually produced four predominant peaks on FPD-GC, and these were identified as 3-methylthiopropanol (methionol), 3-methylthio-propyl acetate, 2-methyl-tetrahydrothiophene-3-one, and dimethyl sulfoxide (DMSO). Ethyl acetate extracts of beer subjected to FPD-GC after methylation had four or five main peaks corresponding to 2-methylthio acetic acid, 3-methylthio propionic acid, 2-hydroxy-4-methylthio butanoic acid, and one or two unidentified components.
Most of these sulfur compounds were found to be present in beers of several different brands at concentrations in micrograms per liter (1 to 68 μg/liter), while methionol and DMSO were present in milligrams per liter (0.4 to 2.3mg/liter). Changes in the quantities of these sulfur volatiles during the brewing process were pursued and discussed.

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The pH of the blue petal juice of ‘Heavenly Blue’ morning glory was 6.88, while the pH of the white parts of the same petal tissues was 5.88. Rutin, caffeic acid and some metals, which were quantitatively detected in blue petal tissues, did not produce a significant bathochromic shift in the visible λ_max of the main petal anthocyanin, dicaffeyl peonidin 3-sophorosido-5-glucoside. Spectral examinations showed that the high pH of the petal cells was the major factor in the blue pigmentation, and the color stability of the main petal anthocyanin could be attributed to its acyl group, caffeic acid. In contrast with the main petal pigment, its deacylated anthocyanin in Mcllvaine's buffer solutions at different pH was easily converted into a colorless pseudobase and besides into other compounds.

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Cucurbitacin D and I were isolated from Phormium tenax Forst. as bitter substances. Farrerol was isolated from the same plant as an antimicrobial agent against Staphylococcus aureus. Although cucurbitacins and farrerol have been isolated from several different plant families, this appears to be the first report of the presence of farrerol in the Liliaceae.

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