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1.
Zone Precipitation Chromatography is useful tech-nique for the initial isolation of the different colla-gen types in their native configuration. Small quan-tities of collagen mixtures can be rapidly separated into different collagen types with relatively high degree of purity, based upon stained protein patterns on sodium dodecyl sulfate polyacrylamide gel electro-phoresis (SDS-PAGE) slab gels. Tn the commonly used bulk salt preparative method for isolating the different collagens, 50 mg of starting material was needed. Three days were required to complete the procedure. The stained protein patterns on SDS-PAGE slab gels showed about 25% contamination with the bulk purified Type III fraction and 20% contamination with the bulk purified type AB collagen. With Zone Precipitation Chromatography 5 mg of starting material was used and in less than 4 hours the mixture was separated with Types III and AB fractions showing less than 10% contamination from other collagen types. The technique is patterned after the Zone Precinitation method reported by Porath seventeen years ago and utilizes a step-wise sodium chloride gradient to precipitate and redissolve the collagens, eluting from the interbead spaces of a molecular sieve column.  相似文献   
2.
An optimized HPLC method with photodiode array detection was developed and applied to analyse the curcuminoids curcumin, demethoxycurcumin, and bis-demethoxycurcumin in rhizomes of Curcuma mangga Val &. v. Zijp, C. heyneana Val. & v. Zijp, C. aeruginosa Roxb. and C. soloensis Val. (Zingiberaceae), indigenous to Indonesia. The method was validated with an isocratic system, a short run time of 10 min and a baseline separation. The curcuminoid content was 0.18-0.47% for C. mangga, 0.98-3.21% for C. heyneana, 0.02-0.03% for C. aeruginosa and 0.40% for C. soloensis.  相似文献   
3.
We evaluated the antimicrobial activity of 25 monoketone curcuminoids (MKCs) against a representative panel of cariogenic bacteria in terms of their minimum inhibitory concentration (MIC) values. Curcumin A ( 10 ) displayed promising activity against Streptococcus mutans (MIC = 50 μg/ml) and Streptococcus mitis (MIC = 50 μg/ml) as well as moderate activity against Ssanguinis (MIC = 100 μg/ml), Lactobacillus casei (MIC = 100 μg/ml), and Streptococcus salivarius (MIC = 200 μg/ml). Results indicated higher activity of compound 10 than that of its bis‐β‐diketone analog. Additionally, compounds 3a (1,5‐bis(4‐methylphenyl)pentan‐3‐one) and 7b (1,5‐bis(4‐bromophenyl)pentan‐3‐ol) were moderately active against Smitis (MIC = 100 μg/ml) and Ssalivarus (MIC = 200 μg/ml).  相似文献   
4.
中药郁金中姜黄素类成分及微量元素分析   总被引:8,自引:0,他引:8  
本文报道了用双波长薄层扫描法对5种郁金中姜黄素类化合物的含量测定结果,同时采用原子吸收光谱法、等离子发射光谱法测定和比较了郁金生药中20种微量元素的含量。  相似文献   
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The three major curcuminoids, curcumin, demethoxycurcumin and bis-demethoxycurcumin, from Curcuma domestica Val. (Curcuma longa L.) and Curcuma xanthorrhiza Roxb. (Zingiberaceae) were fully separated and quantified in less than 5 min using a capillary zone electrophoresis method with standard fused-silica capillaries and photodiode array detection. An electrolyte solution of 20 mM phosphate, 50 mM sodium hydroxide and 14 mM beta-cyclodextrin was found to be appropriate. Quantification was performed with 3,4-dimethoxy-trans-cinnamic acid as internal standard, and the limit of detection was 0.01 mg/mL. Extraction, stabilisation during sample storage and quantification procedures were optimised and carried out with drugs and commercial curry powder from different provenances. The results were compared with the photometric method of the monograph Curcumae xanthorrhizae rhizoma of the European Pharmacopoeia.  相似文献   
7.
One new and five known compounds, which all showed cytotoxic activity, were isolated from the rhizomes of Zingiber zerumbet. The new compound was 3″,4″-O-diacetylafzelin. The known compounds were zerumbone, zerumbone epoxide, diferuloylmethane, feruloyl-p-coumaroylmethane and di-p-coumaroylmethane. Several substituted cinnamoylmethanes were synthesized and tested for cytotoxic properties. Among these were tricinnamoylmethane and triferuloylmethane. The structures were elucidated mainly by spectroscopic methods and 13C NMR data are given.  相似文献   
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植物多酚属于苯丙烷衍生物,包括酚酸类、芪类、姜黄素类和黄酮类等.它们具有抗氧化、扩血管、抗血凝、抗炎、抗肿瘤、抗病毒等生理药理活性,在医药、食品、化妆品、化工等领域具有巨大的应用市场.微生物具有生长快、培养简单、可工业化等优点,成为异源合成天然产物的重要宿主.近年来,合成生物学的发展促进了植物天然产物的微生物合成,并取...  相似文献   
10.
Diabetes exacerbates neuronal injury induced by hyperglycemia mediated oxidative damage and mitochondrial dysfunction. The aim of the present study is to investigate the effects of curcuminoids, polyphenols of Curcuma longa (L.) on oxidative stress and mitochondrial impairment in the brain of streptozotocin (STZ)-induced diabetic rats. A marked increase in lipid peroxidation and nitrite levels with simultaneous decrease in endogenous antioxidant marker enzymes was observed in the diabetic rat brain, which was restored to normal levels on curcuminoids treatment. Down-regulation of mitochondrial complex I and IV activity caused by STZ induction was also up-regulated on oral administration of curcuminoids. Moreover, curcuminoids administration profoundly elevated the ATP level, which was earlier reduced in the diabetic brain. These results suggest that curcuminoids exhibit a protective effect by accelerating antioxidant defense mechanisms and attenuating mitochondrial dysfunction in the brain of diabetic rats. Curcuminoids thus may be used as a promising therapeutic agent in preventing and/or delaying the progression of diabetic complications in the brain.  相似文献   
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