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Kazuko Oshima-Oba Isao Sugiura Ikuzo Uritani 《Bioscience, biotechnology, and biochemistry》2013,77(4):586-591
1. It was demonstrated by silica gel thin layer chromatography that leucine-U-14C was incorporated into furanoterpenes, e. g. ipomeamarone, in sweet potato root tissue infected by Ceratocystis fimbriata.2. Further proof for ipomeamarone synthesis from leucine-U-14C was obtained by the constancy of the specific radioactivity of ipomeamarone semicarbazone through repetitive crystallization.3. The synthetic pathway of ipomeamarone from leucine was found to be connected with the synthetic pathway from acetate at least at some steps.4. Leucine-U-14C was incorporated into both saponifiable and non-saponifiable materials in the same way as acetate-2-14C. 相似文献
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Yoko Takei Kazuko Shimada Susumu Watanabe Tei Yamanishi 《Bioscience, biotechnology, and biochemistry》2013,77(3):645-648
Roasted almond volatiles were isolated by vacuum carbon dioxide distillation of acetone extracts and separated into basic and non-basic fractions. The basic fraction was analyzed by combination gas chromatography-mass spectrometry utilizing open tubular column. Seventeen pyrazines and 2-formyl pyrrole were identified by comparison of their mass spectra with reference spectra. Besides them, five compounds were tentatively identified by mass spectrometry. 相似文献
67.
Charles Santhanaraju Vairappan Takashi Kamada Won-Woo Lee You-Jin Jeon 《Journal of applied phycology》2013,25(6):1805-1813
Secondary metabolites of tropical seaweed are proven to exhibit variety of biological activities. Six species of seaweed (Caulerpa racemosa var. laete-virens, Caulerpa sertularioides f. longipes, Halymenia dilatata, Laurencia snackeyi, Padina boryana, and Sargassum swartzii) were tested for anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Crude L. snackeyi extract exhibit potent activity, and upon bioassay-guided isolation, it contained four halogenated compounds that exert profound inhibitory effects against nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells. These compounds were subjected to spectroscopic measurements and were identified as palisadin A (1), aplysistatin (2), 5-acetoxypalisadin B (3), and palisol (4). Further experiments showed aplysistatin (2) to significantly inhibit NO production and prostaglandin-E2 (PGE2) production, and suppress inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in LPS-stimulated RAW 264.7 cells. Therefore, aplysistatin (2) is suggested to inhibit NO and PGE2 production via the inhibition of iNOS and COX-2, indicating that its activity may be attributed to the modulation of anti-inflammatory agents. 相似文献
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Kenji Miura Hiroyuki Okamoto Eiji Okuma Hayato Shiba Hiroshi Kamada Paul M. Hasegawa Yoshiyuki Murata 《The Plant journal : for cell and molecular biology》2013,73(1):91-104
Transpiration and gas exchange occur through stomata. Thus, the control of stomatal aperture is important for the efficiency and regulation of water use, and for the response to drought. Here, we demonstrate that SIZ1‐mediated endogenous salicylic acid (SA) accumulation plays an important role in stomatal closure and drought tolerance. siz1 reduced stomatal apertures. The reduced stomatal apertures of siz1 were inhibited by the application of peroxidase inhibitors, salicylhydroxamic acid and azide, which inhibits SA‐dependent reactive oxygen species (ROS) production, but not by an NADPH oxidase inhibitor, diphenyl iodonium chloride, which inhibits ABA‐dependent ROS production. Furthermore, the introduction of nahG into siz1, which reduces SA accumulation, restored stomatal opening. Stomatal closure is generally induced by water deficit. The siz1 mutation caused drought tolerance, whereas nahG siz1 suppressed the tolerant phenotype. Drought stresses also induced expression of SA‐responsive genes, such as PR1 and PR2. Furthermore, other SA‐accumulating mutants, cpr5 and acd6, exhibited stomatal closure and drought tolerance, and nahG suppressed the phenotype of cpr5 and acd6, as did siz1 and nahG siz1. Together, these results suggest that SIZ1 negatively affects stomatal closure and drought tolerance through the accumulation of SA. 相似文献
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Background
Numerous studies have reported on the healing powers of plants and nature, but there have not been so many instances of experimental research. In particular, there are very few psychological and physiological studies using tactile stimuli. This study examines the psychological and physiological effects of touching plant foliage by using an evaluation profile of the subjects’ impressions and investigating cerebral blood flow.Methods
The subjects were 14 young Japanese men aged from 21 to 27 years (mean ± standard deviation: 23.6 ± 2.4). With their eyes closed, the subjects touched four different tactile samples including a leaf of natural pothos (Epipremnum aureum). The physiological indices were compared before and after each stimulus. Psychological indices were obtained using a ‘semantic differential’ method.Results
The fabric stimulus gave people ‘soft’ and ‘rough’ impressions, ‘kind’, ‘peaceful’ and ‘pleasant’ feelings psychologically, and a sense of physiological calm. On the other hand, the metal stimulus gave people ‘cold’, ‘smooth’ and ‘hard’ impressions and an image of something ‘artificial’. The metal stimulus caused a stress response in human cerebral blood flow although its evaluation in terms of ‘pleasant or unpleasant’ was neutral. There were no remarkable differences between the stimuli of natural and artificial pothos compared with other types of stimulus psychologically. However, only the natural pothos stimulus showed a sense of physiological calm in the same appearance as the fabric stimulus.Conclusions
This study shows that people experience an unconscious calming reaction to touching a plant. It is to be concluded that plants are an indispensable element of the human environment. 相似文献70.
Naoko Aizawa Hiroshi Kunikata Fumihiko Nitta Yukihiro Shiga Kazuko Omodaka Satoru Tsuda Toru Nakazawa 《PloS one》2016,11(2)