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1.
After acetylation of the phenolic fraction, the following compounds were isolated from Laminaria ochroleuca: phloroglucinol triacetate, diphlorethol pentaacetate (2,4,6,3′,5′-pentaacetoxydiphenyl ether) and triphlorethol C heptaacetate (1-acetoxy-3,5-bis(2,4,6-triacetoxyphenoxy)benzene).  相似文献   

2.
Effects of various concentrations of two heavy metals, namely Cd and Cu, on gametophytes of Laminariajaponica Aresch were determined by recording morphological changes of gametophytes, determining pH values and the heavy metal content of the culture solution, calculating the germination rate of sporophytes, and observing heavy metal (Cd) distribution using a fluorescence microscope. The results showed that heavy metals damaged the gametophytes, and were even lethal, and that the higher the concentration of heavy metal ions, the greater the injury to gametophytes. Gametophytes could not survive in culture solutions containing more than 100 mg/L Cd and 50 mg/L Cu and were only able to survive in culture solution containing a mixture of Cd and Cu up to a concentration of 10 mg/L, which indicates that gametophytes have a higher tolerance to Cd than Cu and that multiple heavy metal ions in solution markedly aggravate the damage to gametophytes compared with individual heavy metal ions. With increases in the concentration of the heavy metal, the burgeoning rate of sporophytes decreased acutely, and solutions containing multiple heavy metal ions caused even more marked harm to sporophytes than solutions containing a single heavy metal ion, because most sporophytes died in mixed solutions. The pH value of the culture medium dropped immediately at the beginning (the first day) of treatment, increased over the following days, and then decreased again. The pH of culture media containing multiple heavy metal ions showed greater variation than media containing a single heavy metal ion, with the extent of the decrease in pH of culture media containing multiple ions being greatest during the last period of the experiment. With increases in the concentration of heavy metals, the capacity of gametophytes to accumulate these ions increased. The blue fluorescent light emitted by the Cd-and Cd-binding protein complex existing in gametophytes in media containing different concentrations of Cd showed clearly the distribution of the ion in gametophytes and the results obtained were consistent with distribution determined using other methods. All results of the present study showed that gametophytes of L. japonica play a remarkable role as heavy metal decontaminators, especially with regard to Cd.  相似文献   

3.
From interpretation of 24-hour dose-response curves, it is improbable that mid-trimester abortion rates greater than about 80% can be accomplished with any one dose schedule of Prostaglandin F2α (PGF2α). To determine whether augmentation of intra-amniotic PGF2α with laminaria would improve the abortion rate, the results of a group of 22 gravidas treated with intra-amniotic PGF2α were compared to those of a group of 21 subjects treated with laminaria and an identical dose schedule of PGF2α. Patients with laminaria not only had a shorter mean abortion time (14.6 hours), but 95% aborted within 24 hours and all patients aborted within 24.5 hours of the initial PGF2α injection. Patients without laminaria had a longer mean abortion time (18.9 hours); only 68% aborted within 24 hours and one failed to abort within the 48-hour trial period. No significant differences in the frequency or severity of complications between the two groups were observed. Uterine contractility over the initial 6 hours of the induction was similar in the two groups. Therefore, augmenting the intra-amniotic PGF2α method with laminaria appears practicable.  相似文献   

4.
Molecular markers were used to identify and assess cultivars ofLaminaria Lamx. and to delineate their phylogenetic relationships. Random amplified polymorphic DNA (RAPD) analysis was used for detection. After screening, 11 primers were selected and they yielded 133 bands in all, of which approximately 99.2% were polymorphic. The genetic distances between gametophytes ranged from 0.412 to 0.956.Two clusters were formed with the unweighted pair group method with arithmetic mean (UPGMA) dendrogram based on the simple matching coefficient. All cultivars ofLaminariajaponica Aresch. used for breeding in China fell into one cluster. L.japonica from Japan, L. saccharina (L.) Lam., and L. angustata Kjellm.formed the other cluster and showed higher genetic variation than L. japonica from China. Nuclear ribosomal DNA (rDNA) sequences, including internal transcribed spacers (ITS1 and ITS2) were studied and aligned. The nucleotides of the sequences ranged from 634 to 668, with a total of 692 positions including ITS1, ITS2, and the 5.8S coding region. The phylogenetic tree obtained by the neighbor-joining method favored, to some extent, the results revealed by RAPD analysis. The present study indicates that RAPD and ITS analyses could be used to identify and assess Laminaria germplasm and to distinguish some species and, even intraspecies, in Laminaria.  相似文献   

5.
Inter-simple sequence repeat (ISSR) analysis was used to assess genetic diversity among 10 pairs of male and female Laminaria gametophytes. A total of 58 amplification loci was obtained from 10 selected ISSR primers, of which 34 revealed polymorphism among the gametophytes. Genetic distances were calculated with the Dice coefficient ranging from 0.006 to 0.223. A dendrogram based on the unweighted pair-group method arithmetic (UPGMA) average showed that most male and female gametophytes of the same species were clustered together and that 10 pairs of gametophytes were divided into four groups. This was generally consistent with the taxonomic categories. The main group consisted of six pairs of gametophytes, which were selected from Laminaria japonica Aresch. by intensive inbreeding through artificial hybridization. One specific marker was cloned, but was not converted successfully into a sequence characterized amplified region (SCAR) marker. Our results demonstrate the feasibility.of applying ISSR markers to evaluate Laminaria germplasm diversities.  相似文献   

6.
Chapman  Anthony R. O. 《Hydrobiologia》1993,260(1):263-267
The objective of the study was to produce a size-based matrix model of a Laminaria digitata (L.) Lamour. population. Hard data for insertion in the matrix were collected in a 9 year cohort analysis of size and age specific survival and fertility for a stand in south west Nova Scotia, Canada. The product of the square matrix containing these values and a column vector containing the densities of size classes was used to project the size class structure one year later. The projected estimates were found to fit empirical estimates with some confidence. In contrast, an age-based fertility life table wrongly predicted a population declining in density by 45% per year. The study supports, in theory, the use of size-based matrix models for management of harvested stands. In reality, the amount of work required to obtain hard data and the site specific nature of the projections may preclude the use of such an approach to broad scale management.  相似文献   

7.
Gao J  Zhang Y  Zhang W  Wu S  Qin S  Zhang W  Yu X 《Biotechnology letters》2005,27(18):1417-1419
Fluctuating light intensity had a more significant impact on growth of gametophytes of transgenic Laminaria japonica in a 2500 ml bubble-column bioreactor than constant light intensity. A fluctuating light intensity between 10 and 110 μE m−2 s−1, with a photoperiod of 14 h:10 h light:dark, was the best regime for growth giving 1430 mg biomass l−1.  相似文献   

8.
海带(Laminaria japonica)丝状体遗传多样性的比较研究   总被引:5,自引:0,他引:5  
王莹  戴继勋 《生物多样性》1999,7(3):197-201
采用垂直板式聚丙烯酰胺凝胶电泳技术对分别来自中国青岛与日本北海道海带(Laminaria japonica)丝状体的6种酶系统(乙醇脱氢酶、谷氨酸脱氢酶、异柠檬酸脱氢酶、乳酸脱氢酶、山梨醇脱氢酶和超氧化物歧化酶)进行了检测,发现存在22个基因位点,分析了不同来源海带丝状体的遗传多样性与遗传分化程度。结果表明:日本北海道海带丝状体的预期杂合度、每个位点有效等位基因数等遗传参数均大于中国青岛海带丝状体。对日本北海道海带丝状体与中国青岛海带丝状体的遗传相似系数和遗传距离进行了计算分析,显示两者发生了遗传分化。日本北海道海带丝状体的遗传多样性高于中国青岛海带丝状体。研究结果还发现在中国青岛海带丝状体的Idh、Ldh 和Sdh中,以及日本北海道海带丝状体的Adh、Gdh、Idh、Ldh、Sdh和Sod中存在着不同迁移率的不等距双带酶,可能由特殊基因控制,并集中在第3个基因位点上。  相似文献   

9.
A compound that stimulated the growth of an arbuscular mycorrhizal (AM) fungus was isolated from 75% methyl alcohol (MeOH) extracts of a brown alga, Laminaria japonica Areschoug, using high-pressure liquid chromatography (HPLC). This compound (Compound 1) was identified as mannitol by HPLC and nuclear magnetic resonance (NMR) spectroscopy. Compound 1 and purchased polysaccharides (alginic acid, fucoidan, carrageenan and mannan from marine algae) were tested for in vitro hyphal growth of an AM fungus, Gigaspora margarita Becker and Hall. Compound 1 (50–500 mg L−1) and carrageenan (1000 mg L−1) significantly stimulated the hyphal growth of germinating spores of Gi. margarita. The application of 100 mg L−1 of Compound 1 to trifoliate orange (Poncirus trifoliata Raf.) inoculated with Gi. margarita promoted root colonization and increased plant growth. These results suggest low concentrations of mannitol are among the reasons for enhanced hyphal growth and root colonization by the application of algal extracts. Other sugar alcohols (100–300 mg L−1 of xylitol, sorbitol and meso-erythritol) also increased the hyphal growth of Gi. margarita.  相似文献   

10.
The variation of 90 Laminaria gametophyte clones representing the introduced Laminaria japonica (Group 1) and Laminaria Iongissima (Group 2), the varieties of L. japonica (Group 3) and the varieties derived from interspecific hybrids (Group 4) was determined with 18 microsatellite markers. The allelic diversity and Nei's gene diversity of Group 1 were significantly higher than those of Group 2 (2.9 vs. 1.8 and 0.414 vs. 0.161, respectively), demonstrating that the variation of the introduced L. japonica is richer than that of L. Iongissima. Both allelic diversity and Nei's gene diversity of Group 3 were lower than those of Group 1, indicating that only a portion of variation of L. japonica was incorporated into the varieties of L. japonica. Significant genetic differentiation was detected between four groups and between female (Population 1 ) and male (Population 2) gametophyte clones in each group. The variation among groups accounted for 39.95%, while that among populations accounted for 21.65% of the total. The genetic distance between Group 1 and Group 4 was obviously longer than that between Group 2 and Group 4 (0.686 vs. 0.291), indicating that maternal gametophyte clone contributed more variation to the hybrids than the paternal gametophyte clone did.  相似文献   

11.
With a "two-way pseudo-testcross" mapping strategy, we applied the amplified fragment length polymorphism (AFLP) markers to construct two moderate density genetic linkage maps for Laminaria. The linkage maps were generated from the 60 progenies of the F1 cross family (Laminaria iongissima Aresch. × L. Japonica Miyabe) with twenty pairs of primer combinations. Of the 333 polymorphic loci scored in 60 progenies, 173 segregated in a 1:1 ratio, corresponding to DNA polymorphisms heterozygous in a single parent, and the other 58 loci existing in both parents followed a 3:1 Mendelian segregation ratio. Among the loci with 1:1 segregating ratios, 79 loci were ordered in 14 linkage groups (648.6 cM) of the paternal map, and 72 loci were ordered in 14 linkage groups (601.9 cM) of the maternal map. The average density of loci was approximately 1 per 8 cM. To Investigate the homologies between two parental maps, we used 58 loci segregated 3:1 for further analysis, and deduced one homologous linkage group. The linkage data developed in these maps will be useful for detecting loci-controlling commercially important traits for Laminaria.  相似文献   

12.
13.
In comparison with results from 1983–1988, when a cartographic study was made on the distribution of the Laminariales and of Sargassum muticum in Lower Normandy (France), we note, on the Calvados coast, a regression of Laminaria digitata which has almost disappeared on the Grandcamp rocks. On the contrary, the growth of the populations of Sargassum muticum is very spectacular at Grandcamp; in summer, 80 % of the substratum in the lower parts of the intertidal zone and in the subtidal are covered by this species.  相似文献   

14.
《Carbohydrate research》1986,148(1):57-62
The oligosaccharides released by the action of endo-(1→3)-β-d-glucanases from the marine molluscs Chlamys albidus (laminarinase Lo) and Spisula sachalinensis (laminarinase LIV) on Laminaria laminarin have been studied. For laminarinase Lo, the branched products were shown to be 62-β-d-glucopyranosyl-laminaribiose and 63- and 62-β-d-glucopyranosyl-laminaritrioses by methylation analysis and 13C-n.m.r. spectroscopy. It is suggested that one or two (1→3) linkages adjacent to (1→6) branch-points result in resistance to enzymic attack. 63-β-d-Glucopyranosyl-laminaritriose inhibited laminarinases Lo and LIV (I50 1.2 × 10−3m and 1.5 × 10−3m, respectively).  相似文献   

15.
Summary High activities of phosphoenolpyruvate-carboxykinase (EC 4.1.1.32) have been found in fronds of the brown alga Laminaria hyperborea (Gunn.) Fosl. The distribution pattern of this enzyme in the newly formed and in the old phylloid (last year's production) and in the cauloid was investigated and compared with that of ribulose-1,5-diphosphate carboxylase (EC 4.1.1.39). Maximum activity of both enzymes is located in the growing region of the new phylloid. In the other parts of the frond, enzyme activity is only about one tenth of the values estimated for the intercalary meristem. The activity of PEP-carboxykinase: RuDP-carboxylase shifts from approxymately 9 in the growing region to only 3 in the old phylloid.
Abkürzungen ADP Adenosin-5-Diphosphat - DTT Dithiothreitol - EDTA Aethylendinitrilotetraessigsäure - PEP Phosphoenolpyruvat - RuDP Ribulose-1,5-Diphosphat  相似文献   

16.
Nutritional attractiveness of the brown alga Laminaria japonica for the sea urchin Strongylocentrotus intermedius was studied. The composition of L. japonica was analyzed after one and two years of its life under natural conditions, in its seedlings, and in the alga partially degraded by natural factors. Substances extracted with various solvents were tested for the presence of inhibitors and activators of 1,3-β-D-glucanase, a digestive enzyme of the sea urchin. Ethanolic extract of freshly harvested L. japonica was found to suppress the enzyme activity. Substances present in ethanolic extracts of the alga after one or two years of its life cycle and in the alga, partly degraded by natural factors, activated the sea urchin enzyme. This fact is in agreement with earlier natural observations concerning the nutritional attractiveness of such L. japonica samples for Strongylocentrotus intermedius.  相似文献   

17.
Zusammenfassung Die Natur der konzentrischen Zonen in den Stämmen von Laminarien ist lange Zeit umstritten gewesen. Nachdem aber im Jahre 1926 nachgewiesen wurde, daß das gesamte vegetative Wachstum bei den nordischen, regelmäßig blatterneuernden Laminarien periodisch und synchron in allen Teilen der Pflanzen erfolgt, war damit bewiesen, daß diese Zonen wirkliche Jahresringe darstellen, die im Zusammenhang mit dem jährlichen Blattwechsel stehen.Ebenso wie die Dendrochronologie die Jahresringe der Bäume als Grundlage für forstliche Untersuchungen über Bestockung, Alter, Produktions- und Verjüngungsverhältnisse im Waldbau benutzt, kann man aus den Jahresringen der nordischen Laminarien entsprechende Rückschlüsse ziehen.Bei der stetig steigenden Nutzbarmachung und Verwendung der Meeresalgen sind derartige Gesichtspunkte von aktuellem Interesse in der Algologie geworden.Vorliegende Arbeit ist ein Versuch, eine Bestandsanalyse in phykochronologischer Regie durchzuführen mit besonderer Berücksichtigung etwaiger Schwankungen in Assoziationen von Laminaria digitata f. stenophylla hinsichtlich Repopulation, Bestockung, Wachstumsverhältnissen und anderer damit verknüpfter biologischer Fragen.Die Untersuchung wurde in den Jahren 1955–1958 an der norwegischen Westküste vorgenommen.Es sei darauf hingewiesen, daß sowohl das vegetative Wachstum als auch die Repopulation bei der genannten Alge von Jahr zu Jahr innerhalb ausgedehnten Grenzen variieren kann und daß diese Pflanze eine nur kurze Lebensdauer hat. Exemplare von mehr als 6 Jahren wurde nicht angetroffen. Ihr Bestand wird deshalb recht rasch erneuert.Professor Dr. E. G. Pringsheim zum 80. Geburtstag gewidmet.  相似文献   

18.
Using a set of methods (C-banding, DAPI-staining, fluorescence hybridization in situ (FISH) with probes of 26S and 5S rDNA, and analysis of meiosis), the first comparative cytogenetic study of three species of Macleaya, producers of complex isoquinoline alkaloids, cordate Macleaya cordata (Willd.) R. Br. (2n = 20), small-fruited Macleaya microcarpa (Maxim.) Fedde (2n = 20) and Macleaya kewensis Turrill (2n = 20), was first carried out. On the basis of morphometric analysis, formulas of karyotypes were made for each species. Species ideograms for M. cordata, M. microcarpa, and M. kewensis were constructed taking into account the polymorphic variants of the C-banding patterns and indicating the location of 26S and 5S rDNA sites. A comparative study revealed that the karyotypes of M. microcarpa and M. kewensis have more in common with each other than with M. cordata. Analysis of meiotic chromosomes suggests of genetic stability of Macleaya genomes. The results of chromosome analysis were used to confirm the close relationship of Macleaya and to clarify their phylogenetic relationships.  相似文献   

19.
A thermosensitive uracil requiring mutant of Bacillus subtilis Marburg 168 thy trp2 ts42 was examined as to the colony forming ability at the permissive and nonpermissive temperatures. The viability of the mutant cells decreased rapidly at the restrictive temperature in the modified Woese’s (MW) medium. However, the cells retained viability when sodium succinate or potassium chloride was added to the medium at that temperature although uracil deficiency was unchanged. A little but significant incorporation of adenine-8-14C into RNA still continued even after the incorporation of N-acetyl-3H-d-glucosamine into acid insoluble fraction of the cells terminated in the MW medium at 48°C. Both incorporations as well as increase of absorbance were slowed down in the presence of sodium succinate at 48°C. This mutant, ts42, was more sensitive to deoxycholate (DOC) than the parent strain. The restoration of colony forming ability after the temperature shift back from 48 to 37°C was suppressed by the addition of DOC to the medium. However, the cell became resistant to DOC when uracil was added to the medium prior to the temperature shift.  相似文献   

20.
The -amylase of Micromonospora melanosporea was produced extracellularly during batch fermentation in a 5.0-1 fermentor. The absence of an organic nitrogen source in its growth medium facilitated subsequent purification of the enzyme by ammonium sulphate fractionation and two consecutive Superose-12 gel-filtration steps. The enzyme exhibited maxima for activity at pH 7.0 and 55° C and was 72% stable at pH 6.0–12.0 for 30 min at 40° C. It had a relative molecular mass of 45 000 and an isoelectric point at pH 7.6. The enzyme catalyses the conversion of starch to maltose (53%, w/w) as the predominant final end-product. Initial hydrolysis of this substrate, however, gave rise to the formation of maltooligosaccharides in the range maltotriose to maltohexaose. Maximum yields of these intermediate sugars accumulated to between 31 and 42% (w/w) as the reaction proceeded. The action of the M. melanosporea amylase on high concentrations of saccharides larger than maltotriose resulted in the formation of mainly maltose and maltotriose without concomitant glucose production. A combination of hydrolytic and transfer events is postulated to be responsible for this phenomenon and for the high maltose levels achieved. Correspondence to: C. T. Kelly  相似文献   

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