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1.
2.
A collection of 4-(4-morpholinophenyl)-6-aryl-6H-1,3-thiazin-2-amines (20–28) were synthesized and their in vitro antimicrobial activity was investigated. Compound 21 against P. aeruginosa, 23 against B. subtilis, 24 against V. cholerae and P. aeruginosa, 26 against S. aureus and B. subtilis, 27 against B. subtilis and E. coli, and 28 against all tested bacterial strains exerted excellent antibacterial activity. Compound 20 against A. flavus and Rhizopus, 21, 26 against Rhizopus, 22, 27 against Mucor, 23 against A. flavus, 24 against both A. flavus and Mucor, 25 against all tested strains, and 28 against Rhizopus and M. gypseum exerted excellent antifungal activity.  相似文献   

3.
The enantioselective hydrolysis of (R,S)-3-acetoxymethyl-7,8-difluoro-2,3-dihydro-4H-[1,4]benzoxazine (I) with enzymes was investigated. Optically active I and its hydrolyzate, 7,8-difluoro-2,3-dihydro-3-hydroxymethyl-4H-[1,4]benzoxazine (II), are the intermediates for preparing optically active ofloxacins, whose racemate is known to be an excellent antibacterial agent. Lipoprotein lipase from Pseudomonas fluorescens (LPL Amano 3) was found to predominantly hydrolyze (S)-I, giving (R)-I in 54% e.e. and (R)-II in 44% e.e. On the other hand, lipase from Candida cylindracea was found to predominantly hydrolyze (R)-I, giving (S)-I in 24% e.e. and (S)-II in 20% e.e. Since, the optical purities of I and II thus obtained were not particularly high, these optically active I and II were converted into 3-acetoxymethyl-7,8-difluoro-2,3-dihydro-4-(3,5-dinitrobenzoyl)-4H-[1,4]benzoxazine (IV). After recrystallizing IV from ethyl acetate-hexane, (S)- and (R)-II were obtained with high enantiomeric excess by removing the crystallized racemic IV and subsequently hydrolyzing the resulting optically active IV with alkali. The reduction of II afforded 7,8-difluoro-2,3-dihydro-3-methyl-4H-[1,4]benzoxazine (III), for which the optical purity was estimated to be >96%e.e. by HPLC analysis. (R)- and (S)-ofloxacin were prepared from (R)- and (S)-III with retention of their configuration.  相似文献   

4.

The sorptive behavior of bacteria—iron oxide composites was investigated in batch metal sorption assays using ferrihydrite in isolation (0.13 and 0.14 g/L ferrihydrite in cadmium and lead systems, respectively) as well as in combination with Bacillus subtilis (0.25 g/L adsorbent mixture) and Escherichia coli (0.27 g/L adsorbent mixture). A pH range from 3.0 to 6.5 was studied using total metal concentrations of 1.0 × 10 ? 4.0 and 3.2 × 10 ? 5 M with adsorbent mixtures proportioned on a 1:1 mass/volume basis. The log of the apparent surface complex formation constants (log K S M ) and sorption capacity (S max ) values were determined by fitting the experimental data to one-site Langmuir sorption isotherms. The one-site model effectively described the sorption data (r 2 > 0.9), where Cd 2 + exhibited somewhat lower sorption affinities (log K S M = ?3 for ferrihydrite, ?1.7 for B. subtilis–ferrihydrite, and ?1.1 for E. coli–ferrihydrite) than Pb 2 + (log K S M = ?0.9 for ferrihydrite, ? 0.2 forB. subtilis–ferrihydrite, and –0.1 for E. coli–ferrihydrite). The corresponding S max values for Cd 2 + and Pb 2 + on ferrihydrite were 0.78 mmole/g and 1.34 mmole/g, respectively. For the B. subtilis–ferrihydrite composites, Cd 2 + and Pb 2 + S max values were lower at 0.29 mmole/g and 0.5 mmole/g, respectively. Similar values were determined for the E. coli–ferrihydrite composites (0.15 mmole/g and 0.68 mmole/g for Cd 2 + and Pb 2 + , respectively). The sorption of Cd 2 + and Pb 2 + by each of the sorbent systems exhibited a strong dependence on pH with sorption edges in the range of pH 4.0 to 7.3. The observed S max of the composites were lower than values predicted upon available site additivity (Cd 2 + B. subtilis ?ferrihydrite : 0.29 mmole/g (observed) < 0.57 mmole/g (calculated); Cd 2 + E. coli ?ferrihydrite : 0.15 mmole/g (observed) < 0.44 mmole/ g (calculated); Pb 2 + B. subtilis ?ferrihydrite : 0.5 mmole/g (observed) < 0.805 mmole/g (calculated); Pb 2 + E. coli –ferrihydrite : 0.68 mmole/g (observed) < 0.775 mmole/g (calculated)), implying that a masking of reactive surface sites by attachment had occurred between the bacteria and ferrihydrite. Electrophoretic mobility analysis indicated that the ferrihydrite surface properties dominate the net surface charge for each composite system with lesser contributions from the bacteria.  相似文献   

5.
Lithospermum (Boraginaceae) comprises approximately 40 species in both the Old and New Worlds, with a center of diversity in the southwestern United States and Mexico. Using ten cpDNA regions, a phylogeny of Lithospermum and related taxa was reconstructed. Lithospermum (including New World and Old World species) and related New World members of Lithospermeae form a monophyletic group, with Macromeria, Onosmodium, Nomosa, Lasiarrhenum, and Psilolaemus nested among species of Lithospermum. New World Lithospermeae also is a monophyletic group, with Eurasian species of Lithospermum sister to this group. Because Lithospermum is not monophyletic without the inclusion of the other New World genera, species from these genera are transferred to Lithospermum, and appropriate nomenclatural changes are made. New combinations are Lithospermum album, Lithospermum barbigerum, Lithospermum dodrantale, Lithospermum exsertum, Lithospermum helleri, Lithospemum leonotis, Lithospermum notatum, Lithospermum oaxacanum, Lithospermum pinetorum, Lithospermum rosei, Lithospermum trinverium, and Lithospermum unicum; new names are Lithospermum chiapense, Lithospermum johnstonii, Lithospermum macromeria, Lithospermum onosmodium, Lithospermum rzedowskii, and Lithospermum turneri.  相似文献   

6.

A new ichnospecies of Arthrophycus Hall 1852, A. minimus , is described from Upper Cambrian-Lower Tremadocian, shallow-marine strata of northwest Argentina. This new ichnospecies consists of small, long, regularly annulated hypichnial elements displaying subcircular to squarish cross-section and a ventral median groove. Side branches are occasionally present, but palmate, fan-like structures and scribbling patterns are absent. We adopt a relatively narrow diagnosis of Arthrophycus , suggesting that roughly annulated, cylindrical structures should not be included in this ichnogenus, unless other diagnostic features (i.e., squarish cross-section, median groove, zipper-like annulations) are also present. Arthrophycus is a common ichnotaxon in Ordovician-Silurian shallow-marine siliciclastic environments. Post-Paleozoic occurrences are removed from Arthrophycus . Arthrophycus has been proposed as a biostratigraphic index fossil in Ordovician-Silurian rocks. The presence of A. minimus in the Santa Rosita Formation of northwest Argentina indicates that Arthrophycus ranges at least from the Upper Cambrian-Lower Tremadocian with probable representatives in the Lower Cambrian and, therefore, its biostratigraphic utility is extended. Arthrophycus minimus represents the first Cambrian occurrence exhibiting not only fine, diagnostic morphologic features, but also the classical Arthrophycus behavioral pattern in dense monoichnospecific assemblages. The exploratory behavioral pattern displayed by A. minimus is simpler than that of the younger ichnospecies, particularly A. brogniartii, A. alleghaniensis, and A. lateralis . This is consistent with the basal position of A. minimus within the arthrophycid lineage.  相似文献   

7.
A revision of the New Caledonian genus Paronthobium Paulian 1984 is presented. Anonthobium Paulian 1984 is synonymized with Paronthobium Paulian 1984 after evaluating the diagnostic characters originally introduced by Paulian to separate them. Upon examination of the type specimens, Onthobium caledonicum Paulian 1935 is separated from O. simplex Fauvel 1903 and restored as valid. Anonthobium moui Paulian 1984 is synonymized with Anonthobium micros Paulian 1984. Fifteen new species are described: P. adio n. sp., P. daghfousi n. sp., P. dierkensi n. sp., P. farino n. sp., P. iac n. sp., P. julieni n. sp., P. memaoya n. sp., P. minutum n. sp., P. nasutum n. sp., P. orientale n. sp., P. peckorum n. sp., P. petchecara n. sp., P. subdentatum n. sp., P. taom n. sp. and P. tchingou n. sp. The genus Paronthobium is now composed of 22 species. Illustrations of parameres and of male protibiae are provided for each species. Distribution maps and a key to species are given.  相似文献   

8.
To evaluate the phylogenetic relationships of species in Pseudoroegneria and related genera, the nuclear ribosomal internal transcribed spacer (ITS) sequences were analyzed for eighteen Pseudoroegneria (St), two Elytrigia (E e St), two Douglasdeweya (StP), three Lophopyrum (E e and E b ), three Agropyron (P), two Hordeum (H), two Australopyrum (W) and two Psathyrostachys (Ns) accessions. The main results were: (i) Pseudoroegneria gracillima, P. stipifolia, P. cognata and P. strigosa (2x) were in one clade, while P. libanotica, P. tauri and P. spicata (2x) were in the other clade, indicating there are the differentiations of St genome among diploid Pseudoroegneria species; (ii) P. geniculata ssp. scythica, P. geniculata ssp. pruinifera, Elytriga caespitosa and Et. caespitosa ssp. nodosa formed the E e St clade with 6-bp indel in ITS1 regions; and (iii) Douglasdeweya wangii, D. deweyi, Agropyron cristatum and A. puberulum comprised the P clade. It is unreasonable to treat P. geniculata ssp. scythica and P. geniculata ssp. pruinifera as the subspecies of P. geniculata, and they should be transferred to a new genus Trichopyrum, which consists of species with E e St genomes. It is also suggested that one of the diploid donor of D. wangii and D. deweyi is derived from Agropyron species, and it is reasonable to treat tetraploid species with StP genomes into Douglasdeweya.  相似文献   

9.
Nine new species of the genus Heliura are described from Brazil (H. brasiliana sp. nov., H. olivocolora sp. nov., H. pulcherrima sp. nov., and H. laerteae sp. nov.), Ecuador (H. ecuadoris sp. nov.), Peru (H. flavipennis sp. nov. and H. peruana sp. nov.), and Venezuela (Heliura albiventris sp. nov. and H. juliani sp. nov.). They are illustrated in habitus and genitalia, and their phylogenetic affinities are discussed based on morphological evidence.  相似文献   

10.
Summary. The Adoretini of the Malagasy endemic genus Adorodocia Brenske 1893 is revised. Fourteen new species and one new subspecies are described and compared with their most closely related species: A. constricta n. sp., A. cuccodoroi n. sp., A. flava n. sp., A. liliae n. sp., A. marginata n. sp., A. peyrierasi n. sp., A. pseudoconstricta n. sp., A. pseudoflava n. sp., A. pseudostrigata n. sp., A. recta n. sp., A. robusta n. sp., A. sogai n. sp., A. vadoni n. sp., A. viettei n. sp. and A. vittaticollis flavipes n. ssp. The synonymy between Adoretus strigatus Waterhouse 1878, and Pseudadorodocia aenigma Arrow 1901, is confirmed. Thus, based on the results of this study, the genus Adorodocia includes 16 species, and one of them is represented by two subspecies. Diagnostic characters to separate the species in the genus deal mostly with the shape of parameres, color of body and legs, shape of pronotum and female eighth tergite, setation of pronotum and elytra. Key to species, diagnoses and distribution for each species are provided. Endophallus and female genitalia are illustrated for the first time for this genus.  相似文献   

11.
It was suggested that the abnormally high N 2 O values found in 130,000–160,000 year-old Vostok ice core samples, characterized by high δ 15 N and low δ 18 O values, resulted from in situ microbial N 2 O production. To substantiate these observations we obtained new geochemical data from the last glacial period and showed the existence of additional small N 2 O anomalies. To test the hypothesis that microbial metabolism could contribute to these anomalies, we developed protocols for examining the ability of Nitrosomonas cryotolerans cells to produce N 2 O at subfreezing temperatures. Our results show that these model, frozen cultures produce N 2 O at temperatures as low as ?32°C.  相似文献   

12.

Because recent patterns of permafrost collapse in boreal peatlands appear to enhance emissions of CH 4 to the atmosphere, we examined methanogenesis and methanogen diversity in peat soil from peatlands with and without permafrost in two peatland complexes situated in continental western Canada. Peat soil from the active layer of permafrost bogs had very low rates of CH 4 production (ca. 10 nmol g ?1 day ?1 ), and we were unable to PCR-amplify 16s rRNA gene sequences using Archaea-specific primers in four peat samples. Surface peat soil from continental bogs with no permafrost supported moderate rates of CH 4 production (20–600 nmol g ?1 day ?1 ), with maximum rates in soil located close to the mean water table level. Additions of ethanol stimulated CH 4 production rates, suggesting metabolic substrate limitations. Peat from internal lawns, which have experienced surface permafrost degradation in the past 150 years, had very rapid rates of CH4 production (up to 800 nmol g ?1 day ?1 ) occurring within the soil profile. Concomitant rates of anaerobic CO 2 production were greater in continental bogs (ca. 6 μmol g ?1 day ?1 ) than in internal lawns (ca. 4 μ mol g ?1 day ?1 ) or in permafrost bogs (2.8 μ mol g ?1 day ?1 ). Analysis of the 16s rRNA gene for Archaea in the continental bog indicated mostly sequences associate with Methanobacteriales and RC-I with a Methanosarcinaceae sequence in the deepest peat soil. In the internal lawn, Methanosarcinaceae were most common in peat soil with a Methanosaetaceae sequence in the deepest peat soil. This study showed that patterns of discontinuous permafrost and ongoing permafrost degradation in boreal regions create patchy soil environments for methanogens and rates of methanogenesis.  相似文献   

13.
Rates of methanogenesis vary widely in peat soils, yet the reasons are poorly known. We examined rates of methanogenesis and methanogen diversity in relation to soil chemical and biological characteristics in 2 peatlands in New York State. One was an acidic (pH < 4.5) bog dominated by Sphagnum mosses and ericaceous shrubs, although deeper peat was derived from sedges. The other was a fen dominated by Carex lacustris sedges with near-neutral pH soil. At both sites, the most active rates of methanogenesis occurred in the top 20 cm of the peat profile, even when using a substrate-induced methanogenesis technique with added glucose that stimulated rates up to 2 μ mol g ? 1 day ?1 in the bog and 6 μ mol g ?1 day ?1 in the fen. Rates of anaerobic CO 2 production were greater in the bog (0–36 μ mol g ?1 day ?1 ) than in the fen (0–5 μ mol g ?1 day ?1 ), and added glucose induced greater rates in the sedge-derived peat from the bog than the fen. The peat soil was much more decomposed throughout the profile in the fen. Analysis of chemical elements in the peat profile revealed a striking anomaly: a very high concentration of Pb in surface peat of the bog, which might have constrained methanogenesis. Application of T-RFLP analysis to methanogens revealed dominance by a Methanomicrobiales E2 clade of H 2 /CO 2 users in the acidic peat soil of the bog, whereas deeper peat had a different Methanomicrobiales E1 clade, uncultured euryarchaeal rice cluster (RC)-I and RC-II groups, marine benthic group D (MBD) and a new cluster called subaqueous cluster (SC). In contrast, T-RFLP analysis of peat from the fen revealed co-dominance by Methanosaetaceae and Methanomicrobiales E1. The results showed complex relationships between rates of methanogenesis, methanogen populations and metabolic substrate availability with idiosyncratic interactions of trace chemical elements.  相似文献   

14.
Variation in inhibition of real-time PCR was investigated with DNA extracts from 50 aquifer sediment core samples of 5 cm length collected through a 2.5 meter vertical profile across a landfill leachate plume. The inhibition was quantified using an internal control of the green fluorescent protein ( gfp ) gene, which was spiked into the real-time PCR reactions. The inhibition was investigated at two gfp gene concentrations: at 1.7 · 10 7 gfp gene copies/g sediment (5.1 · 10 4 gfp gene copies/PCR reaction) and at 1.7 · 10 5 gfp gene copies/g sediment (5.1 · 10 2 gfp gene copies/PCR reaction). Despite the low TOC content of the sediment (average 0.4 mg C/g dw) the average real-time PCR response was partially inhibited, compared to a reference (pure water), at both high and low gfp concentrations. The relative amplification (reference = 1) was 0.85 ± 0.20 (high) and 0.66 ± 0.23 (low), showing significantly (P < 0.05) stronger inhibition at the lower target gene concentration. The inhibition of the real-time PCR did not show a systematic variation in the vertical profile related to plume position but variations were significant on a small scale of 5–15 cm depth intervals. One of the 50 samples failed to produce a signal with either concentration of the gfp internal control and three other samples inhibited real-time PCR at both high and low gfp concentration. These 4 samples, which were the samples with the highest inhibition, were the only DNA extracts with a visible brown colouration, indicating contents of humic-like substances. Elevated absorbance at 400 nm of these samples also indicated that humic-like substances were responsible for inhibition. However, other factors not associated with either absorbance or TOC may have contributed to the inhibition in less inhibited samples since the variation in real-time PCR response could not be sufficiently explained by absorbance or TOC. The results of this study suggest that an internal control is needed in real-time PCR reactions with DNA from environmental samples due to variation in inhibition to correctly quantify the number of target genes, especially at low target gene concentrations, when dilution of DNA extracts is not practical.  相似文献   

15.
The species Anomala aereiventris n. sp., A. aspersa n. sp., A. atrivillosa n. sp., A. clarivillosa n. sp., A. contusa n. sp., A. eusticta n. sp., A. hiata n. sp., A. latifalculata n. sp., A. leopardina n. sp., A. levicollis n. sp., A. longisacculata n. sp., A. m-fuscum n. sp., A. perspicax n. sp., A. piccolina n. sp., A. globulata n. sp., A. stillaticia n. sp., A. subridens n. sp., A. subusta n. sp., A. tenoriensis n. sp., A. tuberculata n. sp. and A. vallisneria n. sp. from Costa Rica are described. These species and A. polygona Bates 1888, A. trapezifera Bates 1888 and A. vulcanicola Ohaus 1897 are placed in a new species-group, named after A. trapezifera, whose diagnosis is provided. Their distribution patterns are discussed.  相似文献   

16.
目的 了解乡镇卫生院各项收支及药品补偿状况,探讨基本药物制度实施后,取消药品加成对乡镇卫生院的影响。方法 收集华东三省49家乡镇卫生院财务及药品收支数据,对定量资料进行统计分析。结果 乡镇卫生院主要的补偿渠道依然是药品收入,乡镇卫生院收入增长主要归因于增加药品收入。在财政补助收入大幅增加的情况下,乡镇卫生院对药品收入的依赖程度有所降低。结论 基本药物制度的实施对乡镇卫生院的平稳运行有影响,可采取加强财政补助、建立综合补偿机制、遏制药品价格虚高等措施保证乡镇卫生院在改革中的平稳运行。  相似文献   

17.

Seasonal variations in precipitation changed the community composition and microbial activity in a hypersaline, tropical microbial mat, in Cabo Rojo, PR. Using a combination of dissection, light, and transmission electron microscopy, terminal restriction fragment length polymorphism (T-RFLP), in situ microelectrode studies, and 35 S isotope incubations, we documented the major differences between wet and dry seasons. During the wet season (precipitation 177 mm), cyanobacterial (green layer) and anoxyphototrophic (pink layer) communities, as well as the black FeS layer were well-developed, and T-RFLP patterns indicated a diverse community. The rate of oxygenic photosynthesis was 49 μ M min ? 1 . Aerobic respiration was 29 μ M min ? 1 , and sulfate reduction was 264 nmol cm ? 3 h ? 1 . During the dry season (precipitation 51 mm), cyanobacteria and anoxyphototrophs were less diverse and abundant, and T-RFLP patterns were less complex. The O 2 production rate was reduced to 9 μ M min ? 1 , as was O 2 consumption (7 μ M min ? 1 ) and sulfate reduction (26 nmol cm ? 3 h ? 1 ). Aragonite, calcite, halite, and quartz were the predominant minerals. Seasonal differences were found in the green and pink layers for both halite and quartz. Gypsum was not observed, likely due to a sample handling artifact. The fluctuations in community composition and metabolic activity, principally reflected in fluctuations in binding and trapping potential of the uppermost mat community, might be responsible for the observed differences in mineralogy.  相似文献   

18.
【背景】武夷菌素高产基因工程菌株Streptomyce albulus OoWysR具有明显的抑菌效果。【目的】明确S.albulus OoWysR的活性成分。【方法】采用柱层析法,利用大孔吸附树脂、离子交换树脂和高效液相色谱等对S.albulus OoWysR的活性成分进行分离纯化,经高分辨率电喷雾电离质谱(high-resolution electrospray ionization mass spectrometry,HR-ESI-MS)和核磁共振(nuclear magnetic resonance,NMR)等波谱技术对化合物化学结构进行鉴定,并通过生长速率法测定化合物的生物活性。【结果】从S.albulus OoWysR中分离鉴定出4个化合物,分别为对羟基苯甲酸(1)、吡咯-2-羧酸(2)、对羟基苯乙醇(3)和云南霉素(4)。化合物1对玉米弯孢病菌、番茄叶霉病菌、玉米小斑病菌和烟草赤星病菌具有一定的抑制作用;化合物2对番茄灰霉病菌、大豆菌核病菌、苹果腐烂病菌、玉米小斑病菌、小麦赤霉病菌、稻瘟病菌和烟草赤星病菌具有一定的抑制作用;化合物3对番茄灰霉病菌、苹果轮纹病菌、玉米小斑病...  相似文献   

19.
The Japanese Clusiidae are revised and 23 species, including 12 species new to science, are recognized and keyed. Clusiodes angulosus n. sp., Clusiodes discostylus n. sp., Clusiodes tobi n. sp., Clusiodes usikumuri n. sp., Craspedochaeta varicolor n. sp., Heteromeringia crenulata n. sp., Heteromeringia quadrispinosa n. sp., Heteromeringia sexramifera n. sp., Heteromeringia yamata n. sp., Phylloclusia quadrivittata n. sp., Sobarocephala uncinata n. sp., and Tetrameringia borealis n. sp. were described as new. Distribution records were compiled and mapped. Transitional climatic zone between the warm and cool temperate zones is possibly suggested as one of the most richest temperate area in terms of Japanese clusiid species richness. Hendelia beckeri Czerny 1903, Paraclusia japonica Sasakawa 1957, and Clusiodes plumosus Sasakawa 1964 are broadly distributed over all the Japanese temperate forests, but these are not always most abundant species. The clusiid assemblage was heterogeneous in the species composition among various forest types. The femalebiased sample caught by Malaise traps and distinction of clusiid species composition between temperate and subtropical zones are also pointed out.  相似文献   

20.
Job Kuijt 《Brittonia》2009,61(2):144-162
Twelve new South American species of Loranthaceae (Aetanthus, Cladocolea, Oryctanthus, and Struthanthus) and Viscaceae (Dendrophthora and Phoradendron) are described and illustrated: Aetanthus trifolius, Cladocolea rostrifolia, Dendrophthora lanceolata, Dendrophthora rotundata, Dendrophthora tenuis, Dendrophthora werffii, Oryctanthus minor, Phoradendron pascoi, Phoradendron vasquezianum, Struthanthus apiculatus, Struthanthus schultesii, and Struthanthus sessiliflorus. Additionally, Cladocolea alternifolia, previously thought to be probably extinct, is reported to occur on Ilha Grande, just west of Rio de Janeiro, Brazil.  相似文献   

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