The stability of chemical components including polymethoxylated flavones (PMFs) such as nobiletin,tangeretin and sinensetin, and synephrine in shiikuwasha ( Citrus depressa Hayata) fruit juice was investigated for four months. The juice tested was prepared from whole fruits by using three types of extractor, namely, a belt-press extractor, a centrifugal extractor and a screw-press extractor, and then stored at temperatures of 5, 20 and 25 °C. The juice yield obtained using the screw-press extractor was higher than those obtained using the other two extractors. Storage temperature had a significant effect on the stability of PMFs and synephrine during 4 month storage, compared with the effect of the extractors. The amounts of PMFs remaining in the fruit juice obtained using the extractors after storage for 4 months at 35 °C, were as follows: 95.1-97.3% of nobiletin, 94.6-97.8% of tangeretin,and 70.2-96.2% of sinensetin. Little change in the amounts of PMFs was observed at 5 and 20 °C. This means that nobiletin and tangeretin are stable. On the other hand, 73.9-87.4% of synephrine remained after 4 months storage at 35 °C , while 41.5-46.7% of vitamin C remained. In sensory evaluation, a marked change in appearance (browning) was observed. From the overall palatability, shelf life of bottled juice prepared using the centrifugal extractor was estimated to be approximately 1 month at 35 °C, 3 months at 20 °C, or 4 months at 5 °C.

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　クマイザサ葉の抗酸化成分を探索したところ，酢酸エチル可溶部から3種のフラボノイドを単離した。それらの構造はスペクトルデータからluteolin 6-C-α-l-arabinoside,luteolin 6-C-β-d-glucoside,luteolin 7-O-β-d-glucosideと決定した。これらのDPPHラジカル消去活性およびSOD様活性を測定した結果，luteolin 6-C-β-d-glucosideが最も強い活性を示し，その活性はquercetinより強かった。

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　The development of a softdrink using a purple potato 'Shadow Queen' was investigated. Purple potato juice was efficiently obtained by 0.1% amylase and pectinase decomposition of a mixture of 1 volume of steamed potatoes with 4 volumes of water. The juice contained a large amount of reducing sugars and some oligosaccharides. Sugar and acid were added to the juice was performed to adjust taste, flavor, and color stability. As a result, a juice with a good taste and flavor was obtained when its composition was adjusted to Brix 8 and its sugar/acid ratio to 19. Moreover, the purple color of the juice was almost unchanged by heat treatment at 80℃ for 30 min for sterilization. The present study revealed the feasibility of developing a novel softdrink made from purple potatoes.

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　カキ‘西条’熟柿の貯蔵性に及ぼす温度と包装の影響を調べた。収穫した‘西条’果実を0℃で数週間貯蔵した後，果実をエチレン処理し熟柿を得た。熟柿の硬度を判定するための新しい判断基準を用いた。すなわち，熟柿からヘタを含む果肉の一部を切除した後果実を縦に半分にカットしたとき，果実横断面と縦断面が形成する縁の崩壊がみられる果実を過軟化果とし，この過軟化果が出現しない最大の期間を熟柿の貯蔵可能期間とした。この基準により，熟柿の貯蔵可能期間は20，10および5℃では，それぞれ2，6日および10日あまりと判断された。有孔ポリエチレン袋個包装およびポリエチレン袋真空個包装により，5℃における熟柿の貯蔵可能期間は20日にも達した。真空個包装では熟柿の中心維管束が水浸状態になったが，異臭は認められなかった。収穫果実のエチレン処理前の低温貯蔵期間の長さは，熟柿の貯蔵性には影響を与えなかった。エチレン処理前低温貯蔵と個包装した熟柿の低温貯蔵を組み合わせることにより，年末まで途切れることなく熟柿を供給することが可能になる。

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