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1.
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   

2.
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   

3.
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   

4.
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   

5.
Abstract

To clarify the structures of biotransformation products and metabolic pathways, the biotransformation of monoterpenoids, (+)- and (?)-camphorquinone (1a and b), has been investigated using Aspergillus wentii as a biocatalyst. Compound 1a was converted to (?)-(2S)-exo-hydroxycamphor (2a), (?)-(2S)-endo-hydroxycamphor (3a), (?)-(3S)-exo-hydroxycamphor (4a), (?)-(3S)-endo-hydroxycamphor (5a), and (+)-camphoric acid (6a). Compound 1b was converted to (+)-(2R)-exo-hydroxycamphor (2b), (+)-(2R)-endo-hydroxycamphor (3b), (+)-(3R)-exo-hydroxycamphor (4b), (+)-(3R)-endo-hydroxycamphor (5b), and (?)-camphoric acid (6b). Compound 1a mainly produced 2a (65.0%) with stereoselectivity, whereas 1b afforded 3b (84.3%) with high stereoselectivity. These structures were confirmed by gas chromatography–mass spectrometry, infrared, 1H nuclear magnetic resonance (NMR), and 13C NMR spectral data. The products illustrate the marked ability of A. wentii for enzymatic oxidation and ketone reduction.  相似文献   

6.

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   

7.
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   

8.
9.
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   

10.
11.
A group of 10 species belonging to the Neotropical tribe Acratini Alonso-Zarazaga, Lyal, Bartolozzi & Sforzi 1999, is shown to be monophyletic by a phylogenetic analysis based on 48 morphological characters. A new genus, Pertusius n. gen., is described, based on three derived characters of external and genital morphology: venter of prorostrum of males with fine median longitudinal carina, base of elytra with deep pit at the place of insertion on mesonotum, and proximal sclerite of endophallus more or less horseshoe-shaped. Eight species were previously known and, according to former authors, belonged to the genera Acratus Lacordaire 1865 [Pertusius apicalis (Sharp 1895), n. comb., P. errabundus (Kleine 1927), n. comb., P. extrarius (Kleine 1927), n. comb., P. fidus (Kleine 1927), n. comb. and P. telesi (Soares & Meyer 1959), n. comb.] and Proteramocerus Kleine 1921 [Pertusius chalcites (Perty 1832), n. comb., P. filum (Sharp 1895), n. comb., and P. laevis (Germar 1824), n. comb.]. Four new synonymies are proposed: Proteramocerus disparilis Soares & Dias 1971, n. syn. for Acratus apicalis Sharp 1895; Teramocerus laevigatus Boheman 1840, n. syn. for Arrhenodes chalcites Perty 1832; Acratus extraordinarius Kleine 1927, n. syn. for Acratus errabundus Kleine 1927; Proteramocerus diringshofeni Soares & Dias 1971, n. syn. for Acratus filum Sharp 1895. Two new species are described: Pertusius guyanensis n. sp. from French Guiana, and P. mexicanus n. sp. from Mexico (Yucatán Peninsula). Pertusius apicalis is newly cited from Bolivia and Peru, P. chalcites from Argentina and Paraguay, P. extrarius from Ecuador, P. fidus from Peru and P. telesi from Trinidad and Tobago and Venezuela. An identification key to species of the genus is provided.  相似文献   

12.
Summary rac-2-Acetoxy-1,1-dimethyl-1-sila-cyclohexane (rac-2) was synthesized by esterification of rac-1,1-dimethyl-1-sila-cyclohexan-2-ol (rac-1) with acetic anhydride. Enantioselective hydrolysis of rac-2 in aqueous solution, catalysed by a crude lipase preparation of Candida cylindracea (EC 3.1.1.3), led to the formation of (S)-1 (95% ee). Enantioselective transesterification of rac-1 with triacetin in isooctane, catalysed by the same enzyme preparation, yielded (S)-2 (95% ee), which was separated by chromatography from non-reacted (R)-1 (96% ee). Recrystallization led to an improvement of the enantiomeric purity of (R)-1 and (S)-1 up to >98% ee. Thus the enantiomers of rac-1 were prepared (100 mg scale) with high enantiomeric purities by the use of two different types of enzyme-catalysed reaction.  相似文献   

13.
Taxonomic changes are made to reflect a reassessment of morphology based on the results of molecular phylogenetic studies. A new genus, Davilanthus, is described to include six species that collectively form the sister group to Simsia, and includes the following species transferred from Viguiera: Davilanthus davilae, Davilanthus hidalgoanus, Davilanthus hypargyreus, Davilanthus huajuapanus, Davilanthus purpusii, and Davilanthus sericeus. Three species formerly placed in Viguiera ser. Grammatoglossae are transferred to Simsia: Simsia benziorum, Simsia ovata, and Simsia rhombifolia.  相似文献   

14.
The genus Xenocylapus Bergroth, 1922 is revised. Nine new species, Xenocylapus aculeatus sp. nov., X. aquilonius sp. nov., X. bicolor sp. nov., X. globulus sp. nov., X. heissi sp. nov., X. panamaensis sp. nov., X. serrulatus sp. nov., X. tenuis sp. nov., and X. waorani sp. nov., are described from Brazil, Honduras, Mexico, and Panama. New genus and species Henryfulvius gracilis gen. nov., sp. nov. is described from Ecuador. Illustrations of the male genitalia, color photographs of dorsal and lateral views of the adult of most species, scanning electron micrographs of selected structures of X. tenuis, and keys to species of the genus Xenocylapus are provided.  相似文献   

15.
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   

16.
【目的】对真菌菌株WH4-2进行鉴定并分离鉴定具有抗菌活性的天然产物。【方法】综合菌落形态和ITS全序列分析,鉴定菌株种属。以抗菌活性分析为导向对其中的活性组分进行分离纯化,波谱分析鉴定结构。采用微量稀释法对化合物进行活性复筛,得最小抑菌浓度MIC值。【结果】真菌菌株WH4-2鉴定为Talaromyces stipitatus。从其土豆发酵液中分离鉴定化合物1 (5S-arugosin K)、2 (5R-arugosin K)、3 (5S-arugosin M)、4 (5R-arugosin M)和5 (Chrysophanol),其中1–4为含异戊烯基的dibenzo[b,e]oxepinone类化合物,5为蒽醌类化合物。1–4对Staphylococcus aureus ATCC43300、ATCC33591,Enterococcus faecium ATCC35667和Bacillussubtilis ATCC6633具有抗菌活性。【结论】含异戊烯基的Dibenzo[b,e]oxepinone类化合物是真菌T. stipitatus中抗菌活性成分。  相似文献   

17.
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   

18.
Sixteen new species of the genus Zorochros Thomson 1859 from China, Indonesia, Malaysia, Nepal and Thailand are described and illustrated, a key to the species of the Zorochros indicus group is given, and new records on already known species are provided. New species: Z. ahrensi n. sp., Z bingkorensis n. sp., Z. dabieshanensis n. sp., Z. dolini n. sp., Z. hartmanni n. sp., Z. hubeiensis n. sp., Z. karnaliensis n. sp., Z. magnificus n. sp., Z. naniensis n. sp., Z. nigredos n. sp., Z. platiai n. sp., Z schawalleri n. sp., Z. schmidti n. sp., Z. senaroensis n. sp., Z. theodori n. sp., and Z. tongshanensis n. sp.  相似文献   

19.
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   

20.
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   

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