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1.
A new snake-eel,Apterichtus keramanus, is described on the basis of a single 276-mm TL specimen trawled from the coast of Kerama Islands, Okinawa Prefecture, Japan.
The species is unique in the genus in having the posterior nostril opening entirely inside the mouth and a dark band running
from the anteroventral margin of the eye to the upper lip. 相似文献
2.
Takahiro Ishii Tatsufumi Okino Yosuke Mino Hiroaki Tamiya Fuyuhiko Matsuda 《Plant Growth Regulation》2007,52(2):131-139
Starfish waste has been shown to be an effective compost material not only in the promotion of plant growth but also in terms
of having insecticidal activity. In the present study, plant growth regulation by chemicals from starfish was examined. The
aqueous fraction from a hot water extract of the starfish Asterias amurensis Lütken showed plant-growth activity, while the aqueous fraction from a methanol extract inhibited growth of Brassica campestris. The lipophilic fraction from the methanol extract also exhibited a plant growth-promoting effect. The active components
from each extract were identified. Asterubine from the hot water extract promoted plant growth. A ceramide from the lipophilic
fraction showed root growth promoting effect, and three glucocerebrosides had promotive effects on the entire plant. Asterosaponins
were identified as the main growth inhibitors in the aqueous fraction of the methanol extract. These active compounds from
starfish waste could be analyzed as potential plant growth regulators in agricultural applications in the future. 相似文献
3.
Whole cells of Chlorella vulgaris and Clostridium butyricum were co-immobilized in 2% agar gel. NADP was suitable as an electron carrier. The rate of hydrogen evolution increased with increasing NADP concentration. The optimum conditions for hydrogen evolution were pH 7.0 and 37°C. The immobilized C. vulgaris-NADP-immobilized Cl. butyricum system continuously evolved hydrogen at a rate of 0.29–1.34 μmol/h per mg Chl for 6 days. On the other hand, the system without NADP evolved only a trace amount of hydrogen. 相似文献
4.
S Yasugi T Matsunaga T Mizuno 《Comparative biochemistry and physiology. A, Comparative physiology》1988,91(3):565-569
1. Stomachs of adult teleosts and elasmobranchs reacted to an anti-embryonic chicken pepsinogen antiserum (anti-ECPg) as well as to an anti-adult chicken pepsinogen antiserum (anti-ACPg). 2. Zymograms and immunoblots of stomach extracts revealed that anti-ECPg- and anti-ACPg-reactive substances possess peptic activity. 3. The possible relationship between anti-ECPg-reactive pepsinogens in fish and prochymosins in higher vertebrates is discussed. 相似文献
5.
Macromolecules purified from Lentinus edodes mycelia cultureenhanced adventitious root formation in Azukia epicotyl cuttings.Partial purification by sequential column chromatographies gavematerial composed of 71% polysaccharides and 29% proteins. Thesugar moiety consisted of mainly xylose, glucose and arabinose,the sum of their contents being more than 76% of the total carbohydrates.The protein moiety consisted of mainly glycine and serine, whichaccounted for more than 40% of the total amino acid residues. (Received June 9, 1984; Accepted November 12, 1984) 相似文献
6.
Isolation and Characterization of an Escherichia coli ruv Mutant Which Forms Nonseptate Filaments After Low Doses of Ultraviolet Light Irradiation 总被引:34,自引:17,他引:17
Two ultraviolet light (UV)-sensitive mutants have been isolated from Escherichia coli K-12. These mutants, designated RuvA(-) and RuvB(-), were controlled by a gene located close to the his gene on the chromosome map. They were sensitive to UV (10- to 20-fold increase) and slightly sensitive to gamma rays (3-fold increase). Host cell reactivation, UV reactivation and genetic recombination were normal in these mutants. Irradiation of the mutants with UV resulted in the production of single-strand breaks in deoxyribonucleic acid, which was repaired upon incubation in a growth medium. After UV irradiation, these mutants resumed deoxyribonucleic acid synthesis at a normal rate, as did the parent wild-type bacteria, and formed nonseptate, multinucleate filaments. From these results we concluded that the mutants have some defect in cell division after low doses of UV irradiation, similar to the lon(-) or fil(+) mutant of E. coli. The ruv locus was divided further into ruvA and ruvB with respect to nalidixic acid sensitivity and the effect of minimal agar or pantoyl lactone on survival of the UV-irradiated cell. The ruvB(-)mutant was more sensitive to nalidixic acid than were ruvA(-) and the parent strain. There was a great increase in the surviving fraction of the UV-irradiated ruvB(-) mutant when it was plated on minimal agar or L agar containing pantoyl lactone. No such increase in survival was observed in the ruvA(-) mutant. 相似文献
7.
T. Matsunaga H. Sudo H. Takemasa Y. Wachi N. Nakamura 《Applied microbiology and biotechnology》1996,45(1-2):24-27
The cyanobacterium, Aphanocapsa halo-phytia MN-11, was immobilized in calcium alginate gel and coated on light-diffusing optical fibers (LDOF) for sulfated extracellular
polysaccharide production. Results indicated that sulfated extracellular polysaccharide production depends on the number of
immobilized cells and the light intensity. In addition, the production rate reached 116.0 mg (mg dry cells)-1 day-1 when the cells that were immobilized on LDOF were incubated under a light intensity of 1380 cd sr m-2 at a cell concentration of 1.0×108 cells/cm3 gel. Cells immobilized on LDOF produced about ten times more sulfated extracellular polysaccharide than those immobilized
in calcium alginate beads only (11.7 mg(mg dry cells)-1 day-1).
Received: 31 March 1995/Revised last revision 12 June 1995/Accepted 26 July 1995 相似文献
8.
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