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1.
The main saponin from the fresh tuber of Dioscorea composita was dioscin and from the fermented material 3-O-[α-l-rhamnopyranosyl(1→4)-β-d-glucopyranosyl]diosgenin. The 13C NMR chemical shifts of saponins were used in the determination of their structure. No free sapogenin was isolated from the fresh tuber.  相似文献   

2.
A new C21 steroidal compound (1), along with 12 known compounds (213) were isolated from the whole herb of Pachysandra terminalis Sieb. et Zucc. Their structures were determined by extensive analysis using various spectroscopic techniques. Notably, compound 6 was reported for the first time from P. terminalis, and compounds 35, 7 and 9 were isolated from the family Buxaceae for the first time.  相似文献   

3.
The purpose of this study was to characterize the antibiotic resistance profiles of Enterococcus species isolated from fresh produce harvested in the southwestern United States. Among the 185 Enterococcus isolates obtained, 97 (52%) were Enterococcus faecium, 38 (21%) were Enterococcus faecalis, and 50 (27%) were other Enterococcus species. Of human clinical importance, E. faecium strains had a much higher prevalence of resistance to ciprofloxacin, tetracycline, and nitrofurantoin than E. faecalis. E. faecalis strains had a low prevalence of resistance to antibiotics used to treat E. faecalis infections of both clinical and of agricultural relevance, excluding its intrinsic resistance patterns. Thirty-four percent of the isolates had multiple-drug-resistance patterns, excluding intrinsic resistance. Data on the prevalence and types of antibiotic resistance in Enterococcus species isolated from fresh produce may be used to describe baseline antibiotic susceptibility profiles associated with Enterococcus spp. isolated from the environment. The data collected may also help elucidate the role of foods in the transmission of antibiotic-resistant strains to human populations.  相似文献   

4.
Three new triterpene saponins, lobatoside O (1), actinostemmoside I (2) and actinostemmoside J (3), were isolated from the herb of Actinostemma lobatum MAXIM. Their structures were elucidated by means of extensive chemical and spectroscopic methods. In addition, cytotoxic activities toward HCT-116, HT-29, MCF-7 and A549 cell lines were tested by the MTT method.  相似文献   

5.
The in vivo ovine model provides a clinically relevant platform to study cardiopulmonary mechanisms and treatments of disease; however, a robust ovine primary alveolar epithelial type II (ATII) cell culture model is lacking. The objective of this study was to develop and optimize ovine lung tissue cryopreservation and primary ATII cell culture methodologies for the purposes of dissecting mechanisms at the cellular level to elucidate responses observed in vivo. To address this, we established in vitro submerged and air-liquid interface cultures of primary ovine ATII cells isolated from fresh or cryopreserved lung tissues obtained from mechanically ventilated sheep (128 days gestation—6 months of age). Presence, abundance, and mRNA expression of surfactant proteins was assessed by immunocytochemistry, Western Blot, and quantitative PCR respectively on the day of isolation, and throughout the 7 day cell culture study period. All biomarkers were significantly greater from cells isolated from fresh than cryopreserved tissue, and those cultured in air-liquid interface as compared to submerged culture conditions at all time points. Surfactant protein expression remained in the air-liquid interface culture system while that of cells cultured in the submerged system dissipated over time. Despite differences in biomarker magnitude between cells isolated from fresh and cryopreserved tissue, cells isolated from cryopreserved tissue remained metabolically active and demonstrated a similar response as cells from fresh tissue through 72 hr period of hyperoxia. These data demonstrate a cell culture methodology using fresh or cryopreserved tissue to support study of ovine primary ATII cell function and responses, to support expanded use of biobanked tissues, and to further understanding of mechanisms that contribute to in vivo function of the lung.  相似文献   

6.
Two new bicyclic lactones, myrotheciumones A (1) and B (2) which possessed a rare ring-fusion system were isolated from Myrothecium roridum (M. roridum), an endophytic fungus of the medicinal herb plant Ajuga decumbens (A. decumbens) via an in vitro cytotoxicity assay. Structures were deduced from 1D and 2D NMR (Nuclear magnetic resonance) data. Myrotheciumone A’s in vitro cytotoxicity and apoptotic activity were evaluated and myrotheciumone A was shown to exert cytotoxicity via inducing apoptosis in cancer cell line.  相似文献   

7.
The frequency of antibiotic resistance was compared inAeromonas spp. isolated from fresh and brackish water in Southern Turkey. A total of 97Aeromonas spp. strains were isolated from four zones (three from fresh and one from brackish water). Most of the strains isolated from all samples wereAeromonas hydrophila (79.4%), while the amount ofAeromonas sobria andAeromons caviae, were rather lower in the samples examined (17.5% and 3.1% respectively). A high proportion of isolates from all water sources showed resistance to cephalotin (86.6%) and trimethoprim-sulphamethoxazole (69%). On the other hand, a low proportion of bacteria showed resistance to tetracycline (14.4%), chloramphenicol (11.3%), gentamicin (7.2%) and nitrofurantoin (6.8%). Only one strain showing resistance to amikacin was found. Multiple Antibiotic Resistance Index (MARI) to at least two antibiotics was highest in brackish water (zone 4), followed by fresh water (zone 3). MARI values ranging from 0.2 to 0.8 for the bacteria isolated from brackish water. This study suggest that, multiple antibiotic resistantAeromonas spp., especiallyA. hydrophila, can be easily recovered from fresh and brackish water sources in Turkey and these sources may play as a reservoirs responsible for disease pathogen aeromonads.  相似文献   

8.
In addition to the known triterpene motiol, hopenol-b (hop-22(29)-en-3β-ol) was isolated from the whole herb of Euphorbia supina. It has not been found previously in nature, though it has been prepared by both synthetic and biosynthetic methods.  相似文献   

9.
Three new C19-diterpenoid alkaloids, tianshanisine (1), tianshanine (2) and tianshanidine (3), together with six known C19-diterpenoid alkaloids (4–9) were isolated from the whole herb of Delphinium tianshanicum W. T. Wang. Their structures were established on the basis of spectroscopic analyses, including HR-ESI-MS and 1D and 2D NMR.  相似文献   

10.
Two new norlignan glycosides, molinerioside D (5) and molinerioside E (9), were isolated from the methanol extract of fresh leaves of Molineria latifolia. Their structures were determined using spectroscopic evidence, such as 1D and 2D NMR and HR-ESI-MS studies. The structure of molinerioside D (5) was determined to be a norlignan glycoside with a C6-C5-C6 skeleton, while the structure of molinerioside E (9) was determined to be a glucosyl-fused norlignan derivative. In addition to the new compounds, twenty known compounds were found in the extract of M. latifolia fresh leaves.  相似文献   

11.
Lactobacillus pobuzihii is a novel species which has been previously found in pobuzihi (fermented cummingcordia), a traditional fermented food in Taiwan. However, the lactic acid bacteria (LAB) microflora in pobuzihi has not been studied in detail. In this study, LAB from pobuzihi were isolated, identified, and characterized. A total of 196 LAB were isolated; 79 cultures were isolated from the sample collected from a manufacturing factory, 38 from pobuzihi samples collected from 4 different markets, and 79 from 2 fresh cummingcordia samples. These isolates were characterized phenotypically and then divided into eight groups (A to H) by restriction fragment length polymorphism analysis and sequencing of 16S ribosomal DNA. Lactobacillus plantarum was the most abundant LAB found in most samples during the fermentation of pobuzihi. On the other hand, Enterococcus casseliflavus and Weissella cibaria were, respectively, the major species found in the two fresh cummingcordia samples. A potential novel species or subspecies of lactococcal strain was found. In addition, seven L. plantarum and five W. cibaria strains showed inhibitory activity against the indicator strain Lactobacillus sakei JCM 1157T. This is the first report describing the distribution and varieties of LAB existing in the pobuzihi during its fermentation process and the final product on the market.  相似文献   

12.
Three selective media for differentiation of Klebsiella pneumoniae from Enterobacter aerogenes on the basis of colonial morphology were evaluated. Using methyl violet 2B as a selective agent, strains of K. pneumoniae isolated from urine, fresh water, and fresh produce were tested against other members of Enterobacteriaceae in addition to strains of Aeromonas hydrophila and Pseudomonas aeruginosa. Comparison of colonial morphology showed K. pneumoniae produced larger, smoother colonies than other bacteria tested. These media were developed to aid in presumptive separation of K. pneumoniae from E. aerogenes in the monitoring of bacterial quality of water.  相似文献   

13.
The mainly fresh water arboviral vector Aedes aegypti L. (Diptera: Culicidae) can also undergo pre-imaginal development in brackish water of up to 15 ppt (parts per thousand) salt in coastal areas. We investigated differences in salinity tolerance, egg laying preference, egg hatching and larval development times and resistance to common insecticides in Ae. aegypti collected from brackish and fresh water habitats in Jaffna, Sri Lanka. Brackish water-derived Ae. aegypti were more tolerant of salinity than fresh water-derived Ae. aegypti and this difference was only partly reduced after their transfer to fresh water for up to five generations. Brackish water-derived Ae. aegypti did not significantly discriminate between 10 ppt salt brackish water and fresh water for oviposition, while fresh water-derived Ae. aegypti preferred fresh water. The hatching of eggs from both brackish and fresh water-derived Ae. aegypti was less efficient and the time taken for larvae to develop into pupae was prolonged in 10 ppt salt brackish water. Ae. aegypti isolated from coastal brackish water were less resistant to the organophosphate insecticide malathion than inland fresh water Ae. aegypti. Brackish and fresh water-derived Ae. aegypti however were able to mate and produce viable offspring in the laboratory. The results suggest that development in brackish water is characterised by pertinent biological changes, and that there is restricted genetic exchange between coastal brackish and inland fresh water Ae. aegypti isolates from sites 5 km apart. The findings highlight the need for monitoring Ae. aegypti developing in coastal brackish waters and extending vector control measures to their habitats.  相似文献   

14.
From the lipophilic fraction of fresh Albatrellus ovinus, the following substances were isolated and identified: E,E-5-methyl-2-(3,7,11 -trimet  相似文献   

15.
《Phytochemistry》1987,26(9):2641-2643
A novel withanolide, daturilin, has been isolated from the alcohol soluble extract of the fresh leaves of D. metel and its structure established as 1-oxo-21,24S-epoxy- (20S,22S)-witha-2,5,25-trienolide through spectral studies including 2D NMR.  相似文献   

16.
A new compound norwedelic acid [5,6-dihydroxy-2(2′,4′,6′-trihydroxyphenyl)-benzofuran-3-carboxylic acid] has been isolated from fresh leaves of Wedelia calendulaceae apart from norwedelolactone, a compound previously found in Eclipta alba.  相似文献   

17.
Two new lupin alkaloids, isokuraramine and (?)-7, 11-dihydromatrine, were isolated from the fresh flowers of Sophora flavescens along with 16 kno  相似文献   

18.
A new guaiane, zedoarondiol, was isolated from fresh rhizomes of Curcuma zedoaria and its structure was elucidated from spectral evidence.  相似文献   

19.
Six ssrRNA gene sequences were obtained by PCR amplification of DNA from uninucleated Entamoeba cysts isolated from fresh faeces of sheep, cows, a roe deer and a reindeer. Phylogenetic analysis using sequences of non-, uni-, quadri- and octonucleate cyst-producing Entamoeba spp. for comparison showed that all six isolates formed a separate clade nested within the clade of quadrinucleate cyst producers. The data indicate that Entamoeba bovis can be isolated from ruminant hosts other than cattle, and we suggest that organisms clustering with the sheep and cattle isolates analysed in the present study be named E. bovis.  相似文献   

20.
Two diketopiperazine derivatives, altenarizines A (1) and B (2), and a new glucosyl sesterterpene, 24-α-d-glucosyl-(−)-terpestacin (3), together with two known phytotoxic sesterterpenes, (−)-terpestacin (4) and fusaproliferin (5), were isolated from the fermentation broth of an endophytic fungus Alternaria alternata, which was obtained from the fresh root of Ceratostigma griffithii. Structures of all the isolates were identified by spectroscopic data.  相似文献   

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