The alcohol extract prepared from young fruits of Japanese pear (Pyrus serotina Rehd. var. culta). The crude extract had strong antioxidative activity for linoleic acid oxidation. The extract contained polyphenols such as chlorogenic acid analogues (Chl) and catechin analogues (Cat). Chl and Cat comprised about 28% and 15% of the polyphenol (PP) contents of the young fruit (590 mg/ 100g fresh weight), respectively. Total PP, Chl and Cat contents were markedly decreased during the fruit development. Linoleic acid oxidation was inhibited 70% and 90% by 5mM Chlogenic acid and Catechin, respectively. Another PP reagents, such as catechol, resorcinol, and hydroquinon also had the antioxidative activity. Above results indicated that PPs, such as Chi and Cat, were the principal constituents of the natural antioxdant of the young fruit extract. The young fruit extract showed the antioxidative activity for about two month. The extract of the young Satsuma mandarin (Citrus unshiu Mar.) fruit, containning a large amount of polyphenols, also showed the antioxidative activity for linoleic acid oxidation. These results suggested that the young fruit extracts were able to employ as a natural antioxidant for fatty foods.

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The entire series of 9-straight chain alkylated acridine derivatives which are acridine (1, C₀) -9-n-octiylacridine (9, C₈) except C₀ were synthesized and C₀ was purchased. The relationship between the number of carbon chains on 9-straight chain alkylated acridine derivatives and their antifungal activity toward Aspergillus niger at pH 3.7, 5.2 and 7.0 was investigated by the paper disc method. The degrees of the antifungal activity of the tested compounds were estimated in terms of both initial strength (IS), which was obtained by measuring the diameter of the inhibition zone around each paper disc with the tested compound after 3 days incubation, and durability of the antifungal activity (DF). The diameter of inhibition zone (16.5mm) of 4-chloro-m-cresol at pH 5.2 after 3 days incubation at 25t was used as a control for the antifungal activity to be defined as f =100. The DF was estimated by the period until inhibition zone disappeared or f value after 10 days incubation when inhibition zone was observed continuously. Though the regularly relationship between the number of carbon chain and the antifungal activity was not consequently found, the existence of optimum number of the carbon chain at each tested pH was suggested. That is, the ranking of IS and DF were as follows.
IS;pH3.7 : C₇ (8) >C₆ (7), C₅ (6) >C₈ (9), C₄ (5) >C₀ (1), C₁ (2), C₂ (3), C₃ (4)
pH5.2 : C₀ (1) >C₄ (5) >C₅ (6) >C₃ (4) >C₇ (8), C₁ (2) >C₂ (3) >C₈ (9) >C₆ (7)
pH7.0 : C₀ (1) >C₁ (2) >C₄ (5) >C₃ (4) >C₅ (6) >C₆ (7) >C₇ (8) >C₈ (9) >C₂ (3)
DF;pH3.7 : C₇ (8) >C₅ (6) >C₆ (7) >C₄ (5) >C₈ (9) >C₁ (2) >C₀ (1) >C₂ (3), C₃ (4)
pH5.2;C₄ (5) >C₅ (6) >C₇ (8) >C₆ (7) >C₈ (9) >C₃ (4) >C₀ (1) >C₁ (2) >C₂ (3)
pH7.0 : C₇ (8) >C₆ (7) >C₈ (9) >C₅ (6) >C₁ (2) >C₀ (1) >C₂ (3), C₃ (4), C₄ (5)

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In order to improve undesirable tastes of soybean foods, total 211 strains of lactic acid bacteria were tested for soybean saponin-hydrolyzing activity. Twenty strains were selected by the acid production from soybean saponins used as carbohydrate sources. Decomposition rates of soyasaponin Bb using high performance liquid chromatography of selected strains were in the range of 3 to 72% and Lactobacillus casei subsp. casei strain IFO 3953 especially indicated a highest value. The optimal pH and temperature of soybean saponin hydrolase in the cell supension and the crude enzyme prepared from cells of the strain were at pH 5.0 and 50°C, respectively. It was presumed that the enzyme would be a β-glucuronidase which cleaves glucuronide bond of soybean saponins from the result of thin layer chromatography analysis.

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Broccoli (Brassica oleracea L. var. italica), komatsuna (B. campestris L.), cauliflower (B. oleracea L. var. botrytis) and cabbage (B. oleracea L.) were stored under air, 0.5% O₂, 1% O₂, 4% O₂ and 7% O₂ atmospheres at 20°C. Volatile sulfur compounds productions and electrolyte leakage from tissue sections of stored commodities were measured. Under 0.5% O₂ atmosphere, methanethiol and dimethyl disulfide productions were detected in komatsuna, broccoli and cauliflower within 24 hours, and were detected in cabbage within 48 hours. At this time, electrolyte leakage from tissue sections was obviously increased as compared with control (stored under air). Under 1% O₂ atmosphere, methanethiol and dimethyl disulfide productions were detected in komatsuna within 48 hours. However, under air, 4% O₂ and 7% O₂ atmosphere, volatile sulfer compounds production was not detected and no significant changes were observed in electrolyte leakage from komatsuna, broccoli, cauliflower and cabbage.

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