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Summary Separation of the soluble proteins from leaves of Perilla by means of gel filtration on a Sephadex Groo column yielded two protein bands with molecular weights of approximately 400,000 and 23,000, which appear to correspond to the well-known Fraction I and Fraction II proteins respectively. The amount of Fraction I protein in the leaves decreased progressively from the time that the leaves became fully expanded whilst the amount of Fraction II protein decreased only in the later stages of senescence. Aleasurements of the activity of several enzymes in successive 4 ml fractions from the column showed that each occupied a different peak position within the two main protein fractions. Fach of the enzymes assayed showed a different pattern of change in the course of senescence of the leaves. These changes in protein content and enzyme activity are discussed in relation to earlier observations on the physiological functioning of senescing leaves of Perilla.

日本産エゴマ(PerillafrutescensBrit.)の精油の検索を進め,広島県宮島産の-エゴマの精油がエゴマケトン(Egomaketone)と命名した新フランケトンを約70%も含有していることを見いだした。本物質は接触還元によりペリラケトンを与え,また過マンガン酸カリウム酸化によりアセトンを生成するからβ-デヒドロペリラケトンに相当する。またその誘導体として2,4-ジニトロフェニルヒドラゾンおよびオキシムをつくった。本精油中にはこのほかマツタケアルコ-ル(約10%)および1-リナロール(約11%)が存在する◇

さきにエゴマ(Perilla Frutescens Brit)の精油成分を検索し,精油の低沸点留分から茸ようの香気を有するC8H160F1なる左旋性の鎖状不飽和アルコール少量を分離したが,このものは著者らがすでにフトボナギナタコヴジュ(Elsholtzia nipponicaOhwi)の精油から分離した鎖状不飽和アルコールと同一物であり,ともにマツタケアルコール(l-1-オクテン-3-オール)に一致することがわかった。マツタケアルコールの新規の合成法としてn-カプロン酸クロリドとエチレンとから1一オクテンー3一オンをつくり,これをPonndorf還元に付して1-オクテン-3-オールとし,このものをもちいて証明した。

シソ(Perilla nankinensis Decne)とエゴマ(P.frutescens Brit.)との雑種と考えられるものの精油をガスクロマトグラフィーにより再検討した。精油の収率生草の0.02～0.03%,油分はα-ピネン0.4～1.8%,β-ピネン0.0～0.9%,リモネン0.7～1.O%,p-シメン0.0～1.2%,3-オタタノール3.7～4.2%,1-オクテン-3-オール5～6,6%,β-ナギナテン(?)0.0～1.4%,2-アセチル-3-メチルフラン0.9～1.5%.リナール8.4～1.5%,リナリルアセテート0.0～3.2%,エルショルチアケトン7.5～20.9%,リナゾルセネシエート0.9～2.8%,未決定物質2.7～19.3%,ツワブキ酸6.1～8.8%,ゲラニオール0.0～2.8%,ナギナタケトン22.5～5.O%,セスキテルペンアルコール0,0～3.1%からなる。さらにこれらの成分の出現様式について若干の考察を行なった。

Herbal products are getting more popular as alternative medicines and food supplements. The therapeutic effects of herbal medicines are mainly attributed to their bioactive secondary metabolites. Orthosiphon aristatus, locally known as ‘Misai Kucing’, is known for its various health benefits. One of the main chemical constituent of O. aristatus is rosmarinic acid, a plant polyphenol that has been proven to have antioxidant, anti-inflammatory and antimicrobial activities. Hydroxyphenylpyruvate reductase (HPPR) is one of the enzymes involved in rosmarinic acid biosynthetic pathway. Here we report the effect of UV on HPPR expression and the isolation of a full-length hppr cDNA from O. aristatus via rapid amplification of cDNA ends polymerase chain reaction. An increase in the expression was detected when the plant was exposed to UV and detected via the expression of hppr transcript. A 1116 bp nucleotide putative cDNA was isolated corresponding to 307 predicted amino acid. We have also isolated the 5’ and 3’ untranslated regions with a length of 54 bp and 123 bp, respectively. Sequence similarity analysis was performed against NCBI genebank and the BLAST result showed that the putative hppr cDNA isolated from O. aristatus exhibited high similarities with other hppr cDNA of the members of the Lamiaceae family such as Perilla frutescens, Salvia officinalis, Salvia miltiorrhiza and Solenostemon scutellarioides.

Summary Nitrate reductase in leaves of Perilla is an adaptive enzyme, the induction of which is shown to require carbon dioxide, light and nitrate. Following illumination of a leaf containing nitrate, the activity of the enzyme rises to a maximum after 6 hours and then begins to decline again. However, the enzyme activity is not entirely lost in such a leaf, provided that a supply of nitrate is maintained. When leaves containing nitrate reductase are placed in darkness, the enzyme breaks down at an approximately linear rate, which is influenced by temperature and by the age of the leaf. Synthesis of the enzyme appears to depend on active photosynthesis, since, when a leaf containing nitrate is illuminated in a CO2-free atmosphere, no detectable enzyme is formed. When a leaf possessing nitrate reductase activity is illuminated in a CO2-free atmosphere, the enzyme activity falls at a similar rate to that which occurs when the leaf is darkened. Thus it is reasonable to conclude that synthesis of the enzyme is dependent upon both light and CO2 and that a continuous breakdown of the enzyme is taking place even during a period of net synthesis. Using this information it becomes possible to estimate and compare the capacity of leaves of different ages to s)nthesize nitrate reductase.

Summary The rate of photosynthesis in the third pair of leaves of Perilla frutescens declined gradually from the time of completion of expansion of the leaves until approximately I week from abscission when there was a more rapid decrease. The decrease in rate of photosynthesis first became apparent in the parts of the lamina proximal to the petiole and gradually extended to the more distal regions. The rate of respiration of the leaf remained approximately constant until I week from abscission when there was a transient rise prior to the final decrease in rate, The gradual decline in photosynthesis was accompanied by a similar decline in the RNA and protein content of the leaf although the chlorophyll content did not change during this period. Measurements of photosynthesis by means of 14CO2 incorporation showed a similar pattern of change and further revealed that the rate of incorporation of label into protein declined more rapidly than did the total protein content, The data are interpreted as suggesting the cessation of synthesis of proteins essential for photosynthesis rather than an increased rate of proteolysis as the cause of the senescence changes.

Cytokinins have been extracted from a wide range of plant tissues1 but little is yet known of changes in the cytokinin content of intact plants during development. Readily measurable quantities of cytokinins have been detected in the xylem sap exuding from cut stems of several plant species2–6. It is probable that this cytokinin flux is important in maintaining the cytokinin status of the shoot. It is known that the concentration of cytokinin in xylem sap is influenced by external factors which affect root physiology7. Flooding or water stress8,9 both decrease the concentration of cytokinin in sap, but application of the growth retardant (2-chloroethyl) trimethylammonium chloride (CCC) increases the concentration10. The extent to which changes occur in the cytokinin activity of sap during normal plant development has, however, been little explored.