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1.
A new species of the genus Harpacticella Sars, 1908 is described from a tidal pool on Jeju Island, Korea. Harpacticella
jejuensis
sp. n. is closely related to Harpacticella
itoi Chang & Kim, 1991, with regard to the structure of P1 exp-1 and enp-1, the length of P1 exp-1 and exp-2, and the setal number of the P5 exopod in males. However, the new species is clearly distinguishable from Harpacticella
itoi by the combined following characters: six setae on the P5 exopod in females, one naked seta on the inner margin of P1 exp-2, the short endopod of P1 compared to the exopod, and a naked long seta on the proximal inner margin of the P5 exopod of males. The mtCOI partial sequence is provided as a DNA barcode for the new species. 相似文献
2.
Josef Holub 《Folia Geobotanica》1970,5(3-4):435-441
69 new names are proposed, viz. for 1 genus (Danthoniastrum), 1 subgenus, 1 section, 37 species, 28 subspecies and 1 variety. Most of the new names refer toOtites (10),Helictotrichon (3),Helianthemum grandiflorum (3),Plantago atrata (3),Rhodax (19) andZerna (17). 相似文献
3.
A new ent-secoaromadendrane-type sesquiterpene hemiacetal, plagiochiline G, was isolated from Plagiochila ovalifolia. Four new ent-sesquiterpene hemiacetals, plagiochiline H and I, and two pungent methoxyplagiochilines A1, A2 and non-pungent methoxyplagiochiline C were also isolated from P. yokogurensis. The methoxylated plagiochilines A1, A2 and C were derived from the plagiochilines A and C during the extraction procedure. A new germacrene, ent-3α-acetoxybicyclogermacrene, ent-maaliol and the previously known ent- aromadendrane-type sesquiterpenes have been obtained from P. yokogurensis. The structures of the new compounds were elucidated by 1H NMR spectral data and by chemical correlation. 相似文献
4.
Nasim Akhtar Muhammad Saleem Naheed Riaz M. Shaiq Ali Asma Yaqoob Faiz-ul-Hassan Nasim Abdul Jabbar 《Phytochemistry letters》2013,6(2):291-298
Rubranonoside (=7-O-α-l-rhamnopyranosyl-4′-O-β-d-glucopyranosylnaringenin; (1), a new flavanone glycoside, rubranin (=(2S,3S,4R)-2-{[(2R,16E)-2-hydroxyhexaeico-16-en]amino}octadecane-1,3,4-triol-1-O-β-d-glucopyranoside; (2), a new sphingolipid, rubradoid (plumieridine-1-O-β-d-galactopyranoside; (3), a new iridoid galactoside, rubrajaleelol (4) and rubrajaleelic acid (5), two new nor-terpenoids together with known iridoids: 1-α-plumieride (6), plumieride p-Z-coumarate (7) and plumieride-p-E-coumarate (8) have been isolated from the EtOAc-soluble fraction of the MeOH extract of Plumeria rubra. Their structures were assigned from 1H, 13C NMR spectra and 2D NMR analyses (COSY, NOESY, HMQC and HMBC experiments) in combination with HRMS experiments and comparison with literature data of related compounds. All the isolates (1–8) were tested for their antioxidant, antiurease, cytotoxic and phytotoxic activities and were found almost inactive. 相似文献
5.
Five new cis-ent-clerodanes, linarenones A–E (1–5) and two known compounds (6 and 7) were isolated from whole plant of Linaria japonica. The structures of these compounds were determined by various spectroscopic analyses (UV, IR, HR–ESI–MS, 1D and 2D NMR). The absolute configuration of five new diterpenoids was confirmed by circular dichroism (CD) analysis and chemical conversion. Cytotoxicity of the isolated compounds against A549 cell lines and Leishmania major were evaluated. The new cis-ent-clerodane 3 was found to be moderately active against A549 cell lines, and new cis-ent-clerodanes 1, 6 and desacetyl-linarienone (7) were active against L. major. 相似文献
6.
One new bourbonane-type (1) and one new cadinane-type (2) sesquiterpenoids, along with one known aromodendrane-type (3) and five known megastigmane-type (4–8) compounds, were isolated from the leaves and twigs of Manglietia aromatica, a Chinese endangered plant that has not been previously phytochemically investigated. The structures and absolute configurations of the new isolates, (1R,4S,5S,6S,7S,10S)-4-hydroxy-bourbon-8-one (1) and (1R,6S,7S)-1-hydroxy- cadin-4,9-dien-8-one (2), were established by means of spectroscopic methods and a combination of experimental and calculated electronic circular dichroism (ECD). Among the isolates, compound 2 was found to show a moderate inhibitory effect against the human protein tyrosine phosphatase 1 B (PTP1B) enzyme, a target for the treatment of type-II diabetes and obesity, with an IC50 value of 83.5 μM. 相似文献
7.
8.
M. Ángeles García Pilar Cabildo Elena Pinilla M. Rosario Torres José Elguero 《Inorganica chimica acta》2010,363(7):1332-9
The behavior in solution and in the solid state of 3(5)-phenyl-1H-pyrazole (7), 3(5)-phenyl-4-chloro-1H-pyrazole (6), 3(5)-phenyl-4-bromo-1H-pyrazole (1), and 3(5)-p-chlorophenyl-4-bromo-1H-pyrazole (8) is discussed in relation to their 3-phenyl (a)/5-phenyl (b) annular tautomerism. Two new X-ray structures are reported: a new polymorph of 1 and the structure of 6. The new polymorph is a 3-phenyl-1H-pyrazole 1a′ trimer while the new structure is a 5-phenyl-1H-pyrazole 6b trimer. The combined use of NMR at low temperature and DFT calculations allows to discuss the tautomerism of the first three pyrazoles and to predict that the fourth one should be a tetramer formed by both tautomers, 8a and 8b. 相似文献
9.
Takaaki Kubota Hiroko Yahata Sunao Yamamoto Shigeki Hayashi Toshiro Shibata Jun’ichi Kobayashi 《Bioorganic & medicinal chemistry letters》2009,19(13):3577-3580
Two new Lycopodium alkaloids, serratezomines D (1) and E (2), were isolated from the club moss Lycopodium serratum var. serratum. Serratezomine D (1) is a new lucidine-type alkaloid, while serratezomine E (2) is a new phlegmarane-type alkaloid. The structures and relative stereochemistry of 1 and 2 were elucidated on the basis of spectroscopic data. Serratezomine D (1) exhibited an inhibitory activity against acetylcholinesterase. 相似文献
10.
11.
Yu Ding Xiang-Rong Tian Hai-Feng Tang Jun-Tao Feng Wei Zhang Wen-Li Hai Xiao-Yang Wang Yi Wang 《Phytochemistry letters》2012,5(3):668-672
Phytochemical investigation on the whole plant of Anemone rivularis var. flore-minore led to the isolation of a new labdane-type diterpene glycoside (1) and a new trihydroxyfuranoid lignanoid glycoside (2), together with three known triterpene and triterpenoid glycosides (3–5). The structures of the two new compounds were elucidated as β-d-glucopyranosyl (13S)-13-hydroxy-7-oxo-labda-8,14-diene-18-oate (1) and (7S,7′R,8R,8′S)-7′-butoxy-7,9′-epoxy-4,4′,9-trihydroxy-3,3′-dimethoxylignane 9-O-β-d-glucopyranoside (2), on the basis of extensive spectral analysis and chemical evidence. Compound 1 is characterized by a glucose (Glc) esterified C-18 carboxyl group, which is a rarely encountered labdane-type diterpene glycoside in nature. The two new compounds (1 and 2) reported here are the first examples of diterpene glycoside and lignanoid glycoside found in the genus Anemone, and the known triterpene and triterpenoid glycosides (3–5) are identified for the first time from the title plant. 相似文献
12.
A. J. Schroeder X.-H. Chen Z. Xiao M. Fitzgerald-Hayes 《Molecular genetics and genomics : MGG》1999,261(4-5):788-795
The yeast Srp1p protein functions as an import receptor for proteins bearing basic nuclear localization signals. Cse1p, the yeast homolog of mammalian CAS, recycles Srp1p back to the cytoplasm after import substrates have been released into the nucleoplasm. In this report we describe genetic interactions between SRP1 and CSE1. Results from genetic suppression and synthetic lethality studies demonstrate that these gene products interact to ensure accurate chromosome segregation. We also describe new mutant alleles of CSE1 and analyze a new temperature-sensitive allele of CSE1, cse1-2. This allele causes high levels of chromosome missegregation and cell cycle arrest during mitosis at the nonpermissive temperature. 相似文献
13.
Zi-Hong Chen Yong-Dong Dai Hong Yu Kun Yang Zhong-Lin Yang Feng Yuan Wen-Bo Zeng 《Microbiological research》2013,168(8):525-532
A new species of Ophiocordyceps, Ophiocordyceps lanpingensis collected from Lanping County, Yunnan Province, southwestern China, was described based on morphological characteristic, ITS1-5.8S-ITS2 rDNA sequences analyses, 5-gene (nrSSU, nrLSU, tef-1α, rpb1 and rpb2) sequences analyses and MAT1-2-1 gene sequences analyses. This species was characterized by thinner stroma, smaller perithecium, thinner ascospore (multiseptate with short septation). The phylogenetic analyses based on the ITS, the 5-gene and MAT1-2-1 gene dataset showed O. lanpingensis had the closest evolution relationship with O. robertsii and O. sinensis, but still had obvious distances to them. Both morphological character and systematic analyses supported that O. lanpingensis was a new species of Ophiocordyceps. 相似文献
14.
Qiangzheng Sun Ruiting Lan Yiting Wang Jianping Wang Xia Luo Shaomin Zhang Peijing Li Yan Wang Changyun Ye Huaiqi Jing Jianguo Xu 《BMC microbiology》2011,11(1):1-6
Background
Shigella flexneri is the major pathogen causing bacillary dysentery. Fifteen serotypes have been recognized up to now. The genesis of new S. flexneri serotypes is commonly mediated by serotype-converting bacteriophages. Untypeable or novel serotypes from natural infections had been reported worldwide but have not been generated in laboratory.Results
A new S. flexneri serotype-serotype 1 d was generated when a S. flexneri serotype Y strain (native LPS) was sequentially infected with 2 serotype-converting bacteriophages, SfX first and then SfI. The new serotype 1 d strain agglutinated with both serotype X-specific anti-7;8 grouping serum and serotype 1a-specific anti- I typing serum, and differed from subserotypes 1a, 1b and 1c. Twenty four S. flexneri clinical isolates of serotype X were all converted to serotype 1 d by infection with phage SfI. PCR and sequencing revealed that SfI and SfX were integrated in tandem into the proA-yaiC region of the host chromosome.Conclusions
These findings suggest a new S. flexneri serotype could be created in nature. Such a conversion may be constrained by susceptibility of a strain to infection by a given serotype-converting bacteriophage. This finding has significant implications in the emergence of new S. flexneri serotypes in nature. 相似文献15.
Two new aporphine alkaloids, named precassythine (1) and (+)− 6S-ocotecine-N-oxide (2), were isolated from Cassytha filiformis. The new structures were elucidated by applying various spectroscopic techniques, including 1D-, 2D NMR and HRESIMS. The absolute configurations of 1 and 2 were determined by calculated electronic circular dichroism (ECD). Both compounds were evaluated for their effects on glucose consumption on HL-7702 cells at different concentrations. The results showed that the two new compounds significantly increased glucose consumption. 相似文献
16.
Yan-Yan Long Ji-Guang Wei Xiang Sun Yue-Qiu He Ji-Tong Luo Liang-Dong Guo 《Mycological Progress》2012,11(3):689-698
In an investigation of Pythium species in lawn grassland of south China, two new species, Pythium breve and P. baisense, were identified based on morphological characteristics and DNA sequence data. These two new species differ morphologically from the other Pythium species by the oogonia encompassed by many antheridia and with 1?C3 antheridia on the wavy and curved stalks. Furthermore, P. baisense with complexly lobed antheridial stalks differs from P. breve with antheridial stalks entwining the hyphae nearby the oogonia with several turns. Results of phylogenetic analyses showed that these two new species were clearly separated from morphologically similar Pythium species based on the internal transcribed spacer region (ITS1, 5.8S, ITS2) and cytochrome c oxidase subunit I (COXI) gene sequences using maximum parsimony and Bayesian methods. These two new species are described and illustrated in detail. 相似文献
17.
Phytochemical investigation of the aerial parts of Lysimachia clethroides led to the isolation of a new acylated flavonol glycoside (1) and a new δ-truxinate derivative (2), together with three known acylated flavonol glycosides. The structures of the new compounds were determined by spectroscopic methods and chemical evidence as quercetin-3-O-β-d-(6-O-Z-p-coumaroyl)glucopyranoside (1) and monomethyl 3,3′,4,4′-tetrahydroxy-δ-truxinate (2), respectively. All of the isolates were evaluated for their in vitro inhibitory activity against aldose reductase. 相似文献
18.
Eleven representatives of diatom algae of the class Centrophyceae from the genera Aulacoseira (1), Conticribra (1), Cyclotella (5), Discostella (1), Stephanodiscus (2), and Thallasiosira (1) have been found in the phytoplankton of 5 volcanic lakes (Bakening volcano, Kamchatka). Stephanodiscus popovskayae, a species new for science, has been discovered in all the lakes, and a species new for the flora of Russia, Cyclotella gordonensis, has been found only in three lakes. The closest similarity in the composition of centric diatoms has been revealed between the lakes of a single water system: Lake Medvezh’e and Lake Verkhneavachinskoe. 相似文献
19.
Wolbachia Transfer from Rhagoletis cerasi to Drosophila simulans: Investigating the Outcomes of Host-Symbiont Coevolution
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Markus Riegler Sylvain Charlat Christian Stauffer Herv Merot 《Applied microbiology》2004,70(1):273-279
Wolbachia is an endosymbiont of diverse arthropod lineages that can induce various alterations of host reproduction for its own benefice. Cytoplasmic incompatibility (CI) is the most common phenomenon, which results in embryonic lethality when males that bear Wolbachia are mated with females that do not. In the cherry fruit fly, Rhagoletis cerasi, Wolbachia seems to be responsible for previously reported patterns of incompatibility between populations. Here we report on the artificial transfer of two Wolbachia variants (wCer1 and wCer2) from R. cerasi into Drosophila simulans, which was performed with two major goals in mind: first, to isolate wCer1 from wCer2 in order to individually test their respective abilities to induce CI in the new host; and, second, to test the theoretical prediction that recent Wolbachia-host associations should be characterized by high levels of CI, fitness costs to the new host, and inefficient transmission from mothers to offspring. wCer1 was unable to develop in the new host, resulting in its rapid loss after successful injection, while wCer2 was established in the new host. Transmission rates of wCer2 were low, and the infection showed negative fitness effects, consistent with our prediction, but CI levels were unexpectedly lower in the new host. Based on these parameter estimates, neither wCer1 nor wCer2 could be naturally maintained in D. simulans. The experiment thus suggests that natural Wolbachia transfer between species might be restricted by many factors, should the ecological barriers be bypassed. 相似文献
20.
Fawley MW 《Plant physiology》1989,91(2):727-732
A new form of chlorophyll c has been isolated from the pyrmnesiophyte Pavlova gyrans Butcher. This pigment is spectrally similar to chlorophyll c2, but all the absorption maxima (454, 583, and 630 nm in diethyl ether) are shifted 4 to 6 nanometers to longer wavelengths. The new pigment can be separated from other chlorophyll c-type pigments by reversed-phase high performance liquid chromatography and thin layer chromatography. Both chlorophylls c1 and c2 are found with the new chlorophyll c pigment in P. gyrans, and it has also been detected in the chrysophyte Synura petersenii Korsh. The light-harvesting function of the new chlorophyll c pigment is indicated by its presence along with chlorophyll c1 and c2 in a light-harvesting pigment-protein complex isolated from P. gyrans in which chlorophyll c pigments efficiently transfer absorbed light energy to chlorophyll a. 相似文献