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31.
The hairy root culture of Lippia dulcis Trev., Verbenaceae, was established by transformation with Agrobacterium rhizogenes A4. The transformed roots grew well in Murashige and Skoog medium containing 2% sucrose. The roots turned light green when they were cultured under 16 h/day light. The green hairy roots produced the sweet sesquiterpene hernandulcin (ca. 0.25 mg/g dry wt) together with 20 other mono- and sesquiterpenes, while no terpenes were detected in the nontransformed root cultures. The growth and hernandulcin production in the hairy root cultures were influenced by the addition of auxins to the medium. The addition of a low concentration of chitosan (0.2 – 10.0 mg / l) enhanced the production of hernandulcin 5-fold.Abbreviations Cht
chitosan
- IAA
indole-3-acetic acid
- NAA
1-naphthaleneacetic acid
- 2,4-D
2,4-dichlorophenoxyacetic acid
- MS
Murashige and Skoog(1962) 相似文献
32.
NADH- and NADPH-dependent formation of superoxide anions by bovine heart submitochondrial particles and NADH–ubiquinone reductase preparation 下载免费PDF全文
1. Both NADH and NADPH supported the oxidation of adrenaline to adrenochrome in bovine heart submitochondrial particles. The reaction was completely inhibited in the presence of superoxide dismutase, suggesting that superoxide anions (O(2) (-)) are responsible for the oxidation. The optimal pH of the reaction with NADPH was at pH7.5, whereas that with NADH was at pH9.0. The reaction was inhibited by treatment of the preparation with p-hydroxymercuribenzoate and stimulated by treatment with rotenone. Antimycin A and cyanide stimulated the reaction to the same extent as rotenone. The NADPH-dependent reaction was inhibited by inorganic salts at high concentrations, whereas the NADH-dependent reaction was stimulated. 2. Production of O(2) (-) by NADH-ubiquinone reductase preparation (Complex I) with NADH or NADPH as an electron donor was assayed by measuring the formation of adrenochrome or the reduction of acetylated cytochrome c which does not react with the respiratory-chain components. p-Hydroxymercuribenzoate inhibited the reaction and rotenone stimulated the reaction. The effects of pH and inorganic salts at high concentrations on the NADH- and NADPH-dependent reactions of Complex I were essentially similar to those on the reactions of submitochondrial particles. 3. These findings suggest that a region between a mercurialsensitive site and the rotenone-sensitive site of the respiratory-chain NADH dehydrogenase is largely responsible for the NADH- and NADPH-dependent O(2) (-) production by the mitochondrial inner membranes. 相似文献
33.
The relationship between the binding patterns of soybean agglutinin, peanut agglutinin (both in their native (unaggregated) form and in their polymerized form), and of Phaseolus vulgaris leucoagglutinin, to neuraminidase-treated lymphocytes from different sources, and the mitogenic activity of these lectins, was studied. In all cases investigated, binding of a lectin to lymphocytes which resulted in stimulation was a positive cooperative process. Our findings support the assumption that clustering of receptors and conformational changes in membrane structure are prerequisites for mitogenic stimulation. 相似文献
34.
Blood group H-active polysaccharide has been prepared from “smooth” strain Escherichia coli 2B-V by Freeman's method. a-Fucosidase derived from Bacillus fulminans caused the liberation of fucose from this polysaccharide, together with concomitant loss of blood group H activity. The results of quantitative microanalysis, borohydride reduction, the Morgan-Elson reaction and enzymic hydrolysis with β-galactosidase using isolated oligosaccharides obtained by partial acid hydrolysis indicated that the O-specific side chain of the polysaccharide has a pentasaccharide unit which is β-d-Gal-(1→3)-d-GalNAc-(1→3)-d-GalNAc-Fuc with a D -glucose residue bound at some undetermined point on this structure. It was considered that terminal non-reducing fucose of the polysaccharide was liberated by partial acid hydrolysis. 相似文献
36.
Summary The electron microscopic structure of the myocardium of the mantis shrimp is descriped. Particular attention is paid to the organization of the nerve terminal and the sarcotubular system. The general appearance of this myocardium is characterized by deep invagination of the plasma membrane at the level of Z-band and large irregular shaped mitochondria. It possesses a very well developed sarcotubular system, consisting of the longitudinal system and two transverse elements making two sets of contact to each other. One forms dyad and the other forms triad at the level of M- and Z-band, respectively. The organization of the myoneural junction in this muscle is very simple and undifferentiated. In general, a special structural differentiation is invariably observed at both sides of the contact area. In spite of the fact that synaptic vesicles and a differentiated membrane are found at the naked process of this cardiac nerve, specialization such as subsynaptic fold formation has not been observed at the muscle side which is in contact with the nerve process. Observations made on the sarcotubular system and the nerve termination have been discussed with reference to their physiological significance. This investigation was supported by the Public Health Service Research Grants HE 06968-04 and NB 03348-04 of the National Institutes of Health, Bethesda, and the U. S. Department of the Army through its Far East Research Office. 相似文献
37.
Hashem Shaharior Kawai Koichiro Fatsi Patrick Senam Kofi Kodama Atsuya Saito Hidetoshi 《Limnology》2020,21(1):151-163
Limnology - The purpose of this study was to estimate the genetic distance, diversity and relationship of two large groups of Malawian cichlid, ‘mbuna’ living in rocky area and feeding... 相似文献
38.
Aya Ibrahim Danielle Kirkpatrick Laura J. Nixon Dalton C. Ludwick Gianfranco Anfora Tracy C. Leskey 《Journal of Applied Entomology》2020,144(7):589-597
The brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae), is an invasive pest that attacks specialty and row crops in North America and Europe. There has been a concerted effort to reduce frequent broad-spectrum insecticide applications made on vulnerable crops. One tool that has emerged recently is the use of long-lasting insecticide-treated nets (LLINs) as a killing agent. Here, we conducted bioassays to evaluate the effect of direct contact on deltamethrin-impregnated LLINs on the behaviour and survivorship of H. halys nymphs and adults in the laboratory. Following exposure at three different durations (1.25, 4.25 or 7.25 min), vertical and horizontal mobility of adults and nymphs and the flight capacity of adults were recorded and compared with individuals that were not exposed (control). Exposure to LLINs reduced the horizontal distance and velocity and increased the angular velocity of adults only but reduced vertical mobility of adults and nymphs. Adult flights were not significantly affected by LLIN exposure. Mortality of adults and nymphs at 7-day post-exposure ranged from 73% to 77% regardless of exposure time. We discuss our findings within the context of the potential for and limitations of deploying LLINs in vulnerable crops to manage H. halys populations. 相似文献
39.
40.
Takemura Aya Matsumoto Junya Hashimoto Ryota Kawano Kenji Miura Kenichiro 《Journal of computational neuroscience》2021,49(3):273-282
Journal of Computational Neuroscience - When two-frame apparent motion stimuli are presented with an appropriate inter-stimulus interval (ISI), motion is perceived in the direction opposite to the... 相似文献