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1.
Several feather-degrading bacterial isolates were isolated from Egyptian soil. These isolates were able to degrade chicken feather, when grown on basal medium containing 1% native feather as a source of energy, carbon, and nitrogen. Feather waste, generated in large quantities as a byproduct of commercial poultry processing, is nearly pure keratin, which is not easily degradable by common proteolytic enzymes. The isolates were identified according to the morphological characteristics, biochemical tests, and API 50 CHBBacillus system. Proteolytic and keratinolytic activities of these isolates were monitored throughout the cultivation of the bacterial isolates on feather. Resulting soluble proteins, which were released as a result of the biodegradation of feather, were demonstrated by SDS-PAGE.  相似文献   

2.
铕对决明发根生长及有效成分生成的作用   总被引:2,自引:0,他引:2  
以决明发根为材料,在培养基中附加0.001~10mg.L^-1Eu^3+(EuC13),测量发根的鲜重和干重,用高效液相色谱法测定游离蒽醌化合物含量。发有低剂量(0.001,0.01,1.0mg.L^-1)Eu^3+抑制生长,0.001mg.L^-1Eu^3+抑制作用最强,干重比对照降低22%;较低剂量(10mg.L^-1)Eu^3+处理的含量高于对照26^,高于Eu^3+1.0mg.L^-1处理  相似文献   

3.
An MEKC method was developed for the determination of the five pharmaceutically important anthraquinones: chrysophanol (1), physcion (2), emodin (3), aloe-emodinin (4), and rhein (5) in Cassia obtusifolia (Leguminosae). A buffer solution (pH 9.00) composed of 20 mM sodium borate, 20 mM sodium deoxycholate (DOC), and 15% ACN was found to be the most suitable electrolyte for this separation. Regression equations revealed linear relationships (correlation coefficients: 0.9993, 0.9992, 0.9996, 0.9989, and 0.9991) between the peak area of each compound (1, 2, 3, 4, and 5) and its concentration. The RSDs of migration times and peak areas were <1.23 and 2.72% within 1 day, respectively. The effects of pH value, surfactant (DOC) concentration, and organic modifier on the migration were also studied. By this way, the contents of five anthraquinones in the extracts of the seed of C. obtusifolia (Leguminosae) from different sources were successfully determined within 14 min.  相似文献   

4.
用反相高效液相色谱法分离并测定了决明子中芦荟大黄素和大黄素,建立了该中药中芦荟大黄素、大黄素分离、测定的色谱方法。色谱条件:ODS柱,甲醇-水(80∶20V/V)为流动相,检测波长223nm。本研究为决明子的质量评价提供了科学依据。  相似文献   

5.
Isolation and identification of nondestructive desulfurization bacterium   总被引:3,自引:0,他引:3  
A nondestructive desulfurization microorganism has been isolated. The metabolism product analyses show that the strain can be a kind of biocatalyst to oxidize dibenzothiophene (DBT) into 2-hydroxydiphenyl (HBP), therefore the sulfur in DBT is removed selectively. The 16SrRNA information, cell wall analysis, physical, biochemical properties and morphological properties suggest that the isolated strain is Rhodococcus erythropolis. The strain can grow in the basal salts medium (BSM) that DBT concentration is no more than 10 mmol/L, and the optimal DBT concentration for growth is 1 mmol/L, however, the optimal DBT concentration for desulfurization is 0.5 mmol/L. The further research shows that the strain can also desulfur some other or-ganosulfur-containing compounds such as thianaphthene, phenyl sulfide and 4,6-dimethyldiben-zothiophene (4,6-DMDBT).  相似文献   

6.
Cassia obtusifolia L., of the Leguminosae family, is used as a diuretic, laxative, tonic, purgative, and natural remedy for treating headache, dizziness, constipation, tophobia, and lacrimation and for improving eyesight. It is commonly used in tea in Korea. Various anthraquinone derivatives make up its main chemical constituents: emodin, chrysophanol, physcion, obtusifolin, obtusin, au rantio-obtusin, chryso-obtusin, alaternin, questin, aloe-emodin, gluco-aurantio-obtusin, gluco-obtusifolin, naphthopyrone glycosides, toralactone-9-β-gentiobioside, toralactone gentiobioside, and cassiaside. C. obtusifolia L. possesses a wide range of pharmacological properties (e.g., antidiabetic, antimicrobial, anti-inflammatory, hepatoprotective, and neuroprotective properties) and may be used to treat Alzheimer’s disease, Parkinson’s disease, and cancer. In addition, C. obtusifolia L. contributes to histamine release and antiplatelet aggregation. This review summarizes the botanical, phytochemical, and pharmacological features of C. obtusifolia and its therapeutic uses.  相似文献   

7.
Procedures were developed for the heterocyclization of 2-benzoylethynyl-1-hydroxy-and 1-hydroxy-2-(1-oxo-3-phenylpropynyl)anthraquinone. The regioselective preparation of 2-substituted anthra[1,2-b]pyran-4,7,12-triones was demonstrated to be possible under mild conditions.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2686–2692, December, 2004.  相似文献   

8.
Traditional bioassay-guided investigation of bioactive compounds from natural products comprises critical steps, such as extraction, repeated column separation, and activity assay. Thus, the development of facile, rapid, and efficient technology is critically important. Here, a HepG2 cell-based extraction method was first developed to rapidly screen potential antitumor compounds from the seeds ofCassia obtusifolia. Then, an online extraction and enrichment–high-speed counter-current chromatography (HSCCC) strategy was fabricated to facilely and efficiently isolate target antitumor compounds, which included direct extraction from solid C. obtusifolia, removal of polar interferences, enrichment of target compounds, and preparative isolation by HSCCC using flow rate stepwise increasing mode. After further purification by Sephadex LH-20 column, five antitumor anthraquinones, aurantio-obtusin, 1-desmethylaurantio-obtusin, chryso-obtusin, obtusin, and questin, were obtained for structural characterization and bioassay verification. The results may not only provide new perspectives for facile and rapid investigation of bioactive compounds from complex natural products, but also offer a scientific basis for the potential applications of C. obtusifolia.  相似文献   

9.
Sulfate-dependent anaerobic ammonium oxidation is a novel biological reaction,in which ammonium is oxidized with sulfate as the electron acceptor under anoxic conditions.Ammonium and sulfate are cosmopolitan chemical species which are an integral part of the global nitrogen and sulfur cycles.A detailed exploration of sulfate-dependent anaerobic ammonium oxidation is quite practical.In this work,a bacterial strain named ASR has been isolated from an anaerobic ammonia and sulfate removing reactor working unde...  相似文献   

10.
一株硫酸盐型厌氧氨氧化菌的分离和鉴定   总被引:5,自引:0,他引:5       下载免费PDF全文
以硫酸盐为电子受体、氨为电子供体的反应称为硫酸盐型厌氧氨氧化,这是一个新的生物反应.迄今为止,虽已证明硫酸盐型厌氧氨氧化的存在,但并未获得进行该反应的微生物.本课题组从长期稳定运行的厌氧脱氮除硫反应器污泥中,分离获得了一株硫酸盐型厌氧氨氧化菌.形态观察、生理试验和16SrDNA序列比对表明,该菌株可归入Bacillus benzoevorans.以Biolog板检测发现,该菌株可利用多种碳源,基质多样性明显.其最适代谢pH为8.5,最适代谢温度为30℃.研究证明,该菌株可在无氧条件下,同时去除氨氮和硫酸盐,具有硫酸盐型厌氧氨氧化活性.这一发现为硫酸盐型厌氧氨氧化的确认提供了生物学证据,为新型生物脱氮除硫工艺的研发打下了基础,为微生物学增加了新的内容,为地球氮素和硫素循环提供了新的认识.  相似文献   

11.
From the butanolic and the ethyl acetate extracts of Rhamnus alaternus L root bark and leaves, three new anthraquinone glycosides, alaternosides A-C (1,4,6,8 tetrahydroxy-3 methyl anthraquinone 1-O-ß-D-glucopyranosyl-4,6-di-O-α-L-rhamnopyranoside (1); 1,2,6,8 tetrahydroxy-3 methyl anthraquinone 8-O-ß-D-glucopyranoside (2) and 1, 6 dihydroxy-3 methyl 6 [2′-Me (heptoxy)] anthraquinone (3)) were isolated and elucidated together with the two known anthraquinone glycosides, Physcion-8-O-rutinoside (4) and emodin-6-O-α-L-rhamnoside (5) as well as with the known kaempferol-7-methylether (6), β-sitosterol (7) and β-sitosterol-3-O-glycoside (8). Their chemical structures were elucidated using spectroscopic methods (1D-, 2D-NMR and FAB-MS). Free radical scavenging activity of the isolated compounds was evaluated by their ability to scavenge DPPH. free radicals. Compounds (3), (4) and (6) showed the highest activity with IC50 values of 9.46, 27.68 and 2.35 μg/mL, respectively.  相似文献   

12.
Many types of anthocyanins are present in Vitis amurensis Rupr of ‘Beibinghong’, which is grown in North-east China and has high antioxidant activity. However, the anthocyanin with the highest content in V. amurensis Rupr has not yet been identified. In this study, pulsed electric field extraction and semi-preparative liquid phase separation were used to isolate the anthocyanin monomer from ‘Beibinghong’. UV–vis spectroscopy, FTIR spectroscopy, mass spectra and nuclear magnetic resonance were used to identify the anthocyanin monomer. The antioxidant activities of the anthocyanin monomer were also analysed. Malvidin-3,5-O-diglucoside was identified as the main anthocyanin in V. amurensis Rupr, which could be used as a raw material for its extraction. Furthermore, malvidin-3,5-O-diglucoside can be potentially used as a functional food, and a novel therapeutic and preventive agent for oxidative stress-related diseases. This study provides technical information for the future purification and structural identification of anthocyanins.  相似文献   

13.
A racemic glycidyl butyrate resolving strain, preliminarily identified as a Rhizopus sp., had been isolated from soil. Its extracellular lipase was found to enantioselectively hydrolyze the (S)-enantiomer of the chiral ester, with optimal activities at pH 5.3 and 42°C. Higher en antioselectivity of theenzyme was observed at lower temperatures, while the best anantioselectivity was obtained at pH 5.5–6.0, with an, E value (enantiomeric ratio) of 57.  相似文献   

14.
麝香草的新单萜配糖物的分离与合成   总被引:1,自引:0,他引:1  
从麝香草(Thymus vulgaris L)的甲醇萃取物中分离出三个单萜配糖物. 用核磁共振光谱确定了它们的结构为对伞花-9-基-β-D-葡糖苷(1), 5-β-D-葡糖苷百里氢醌(2)和2-β-D-葡糖苷百里氢醌(3). 其中1是新化合物, 用以对伞花-9-醇为原料的对映体选择性合成方法确定了化合物1的8位的立体化学为R型.  相似文献   

15.
In this study, the antioxidant activity of aqueous and ethanol extracts of four plants from the genus Cassia were evaluated by various antioxidant assays, including ferric reducing antioxidant power (FRAP), DPPH free radical scavenging, metal chelating activity, phosphomolybdenum reducing power, hydrogen peroxide radical scavenging, hydroxyl radical scavenging, deoxyribose degradation and β-carotene bleaching assay. The various antioxidant activities were compared to standard antioxidant such as ascorbic acid. All the extracts showed antioxidant activity in the tested methods. Among the four species, Cassia auriculata has been found to possess highest activity in most of the tested models. In addition to the antioxidant activity, the total phenolics and flavonoids were measured in the extracts. The ethanolic extract exhibited highest phenolics and flavonoid contents and had also shown potent antioxidant activity in comparison to the aqueous extracts. The possible antioxidant mechanism of the ethanol extract can be due to its hydrogen or electron donating and direct free radical scavenging properties. Hence, the ethanol extract represents a source of potential antioxidants that could be used in pharmaceutical industries.  相似文献   

16.
An efficient micellar electrokinetic chromatography (MEKC) method has been developed for the analysis of nine anthraquinones and bianthrones in rhubarb. A chemometric approach was used to search for the optimum conditions of separation. Those factors which were found to be significant with a screening design were further optimized with a central composite face-centered (CCF) design. Acetonitrile concentration was found to be the most influential, not only in resolution, but also in analysis time and peak asymmetry. With the optimized conditions: 15 mM sodium tetraborate/15 mM sodium dihydrogenphosphate buffer, 30 mM sodium deoxycholate, pH 8.6, 17 vol.% acetonitrile and 28 kV, nine tested analytes were baseline-separated within 14 min. The method was validated to analyze the rhubarb material. Solid-phase extraction (SPE) was manipulated to remove interfering substances. Five anthraquinones and two glycosidic bianthrones were detected and quantificated. The method should be suitable for determining these major active principles in rhubarb crude drugs.  相似文献   

17.
The regioselectivity of reduction of 1-substituted anthraquinones to 1- or 4-substituted anthrones is determined by both the nature of the substituent and the type of the reducing system used. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 355–357, February, 1997.  相似文献   

18.
Recent results obtained on determining the extraction efficiency and composition of organic volatiles in Oregano Water obtained from Origanum onites L. are described. Oregano Water was subjected to liquid-liquid extraction with a range of solvents with different polarities and each extract was analyzed by GC/MS.  相似文献   

19.
主客体包结法选择分离白花前胡的化学成分   总被引:3,自引:0,他引:3  
以1,1,6,6-四苯基-2,4-己二炔-1,6-二醇为主体分子, 可简单、迅速地从白花前胡粗提物中选择分离有效成分3'-乙酰氧基-4'-β-羟基丙酰氧基-3',4'-二氢邪蒿内酯, 收率为0.17%. IR, 1H NMR, 13C NMR光谱和单晶衍射证实了包结化合物的形成及其晶体结构, 并且用气相色谱方法(GC)评价了选择分离效果.  相似文献   

20.
Three lectins designated as CSL‐1, CSL‐2 and CSL‐3 were purified from Cassia fistula seeds by gel filtration on Sephadex G‐50 followed by ion‐exchange chromatography on DEAE cellulose and finally by affinity chromatography on Sepharose 4B. The molecular weights of the lectins CSL‐1, CSL‐2 and CSL‐3, determined by gel filtration on Sephadex G‐75 column were 37,000, 42,400 and 46,000, and by SDS gel electrophoresis were 37500, 42000 and 46500, respectively. All three lectins agglutinated rat red blood cells and the agglutination was inhibited specifically by galactose and galactose containing saccharide. The neutral sugar contents of the lectins, CSL‐1, CSL‐2 and CSL‐3 were estimated to be 3.5, 3.1 and 2.0%, respectively. The sugar composition of the lectins was found to be galactose in CSL‐1, galactose and glucose in CSL‐2, and galactose and mannose in CSL‐3. The lectins exhibited maximum hemagglutinating activities around pH 7.2 to 7.5 and at a temperature range of 20° to 35 °C. Biological activities of the lectins were abolished sequentially with the increase in concentration of acetic acid and denaturant solutions such as urea and guanidine‐HCl.  相似文献   

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