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Countercurrent chromatography us a kund of contunuous and effectuve luquud-luquud partutuon chromatography wuth many unuque characterustucs such as large load capacuty, no urreversuble adsorptuon, hugh recovery rate, low rusk of sample denaturatuon and so on, whuch has urreplaceable advantages un separatuon of proteun and peptude. Thus revuew presents the advances of several kunds of new technology of countercurrent chromatography un the separatuon of proteun and peptude. The developung prospect of thus fueld us also duscussed.
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OBJECTIVE:To optimize ultrasonic extraction and purification technology of solanesol from tobacco leaf. METH-ODS:Using extraction rate and transport rate of solanesol as indexes,single factor test was used to investigate liquid-solid ratio, ultrasonic extraction temperature and time,ultrasonic power and extraction times,and the amount of soap alkali lye(volume ratio of soap alkali lye to extraction liquid),acidizing fluids (volume ratio of acidizing fluids to soap alkali lye extract),extraction times of purification technology. Optimized technology was validated,and the purity of solanesol was calculated;the amount of ex-tracted solanesol was compared between this method and traditional extraction method (spending 30 h),solvent continuous cyclic extraction (spending 5-6 h). RESULTS:Optimized extraction technology was as follows as volume ratio of soap alkali lye to ex-traction liquid 1∶14,ultrasonic extraction temperature 70 ℃,ultrasonic extraction time 60 min,ultrasonic power 120 W,extract-ing for 3 times;optimized purification technology was as follows as volume ratio of soap alkali lye to extraction liquid 2∶35,vol-ume ratio of acidizing fluids to soap alkali lye extract 2∶14,extracting for 4 times. In validation test,extraction rate,transport rate and purity were 92.45%(RSD=0.46%,n=3),79.88%(RSD=0.30%,n=3)and 55.86%(RSD=0.40%,n=3). The amount of solanesol extracted with 3 methods were 52.22,45.22 and 26.10 mg/g. CONCLUSIONS:The optimized technology is simple and stable,costs less time and saves source with high extraction amount and purity,which is suitable for production,extraction and purification of solanesol from tobacco leaf.
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A simple and effective high-performance liquid chromatography with diode-array detection method coupled with a liquid-liquid extraction pretreatment has been developed for determining the pharmacokinetics and tissue distribution of a novel structurally modified derivative (8-acetamino-isocorydine) of isocorydine. According to the in vivo experiments data calculations by DAS 2.0 software, a two-compartment metabolic model was suitable for describing the pharmacokinetic of 8-acetamino-isocorydine in rats. 8-Acetamino-isocorydine was absorbed well after oral administration, and the absolute bioavailability was 76.5%. The half-life of 8-acetamino-isocorydine after intravenous and oral administration was 2.2 h and 2.0 h, respectively. In vivo, 8-acetamino-isocorydine was highly distributed in the lungs, kidney and liver; however, relatively little entered the brain, suggesting that 8-acetamino-isocorydine could not easily pass through the blood brain barrier. Our work describes the first characterization of the pharmacokinetic parameters and tissue distribution of 8-acetamino-isocorydine. The acquired data will provide useful information for the in vivo pharmacology of 8-acetamino-isocorydine, and can be applied to new drug research.
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Transforming technology for semi-synthesized isocorydione from the natural product ofisocorydine was studied. The factors affecting on the reaction yield were investigated. UV spectrophotometry was used to indicate the semi-synthesized yield of isocorydione. The optimum reaction conditions were determined as following: reacting for 12 h in the solution of sodium dihydrogen phosphate at pH 10, the temperature was 25 degrees C and the ratio of isocorydine to Fremy's radical was 1 : 2. Under the optimum conditions, the yield could reach up to 50.0%. The molecular structure of isocorydione was elucidated by X-ray single-crystal diffraction analysis for the first time.
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<p><b>OBJECTIVE</b>To investigate the effect of long-term and low-level occupational Mn exposure on the level of uric acid (UA) in human urine.</p><p><b>METHODS</b>In this study, 65 volunteers were recruited, who were working on welding and foundry work in an plant in Gansu province, China. Additionally, 29 control samples were collected from individuals who did not have any history of excessive Mn exposure. An improved high performance liquid chromatography system equipped with a diode-array detector (HPLC-DAD) method was developed to determine the UA level in human urine. A Spectra AA 220 Atomic Absorption Spectrophotometer (AAS) was used to measure the Mn level in the urine.</p><p><b>RESULTS</b>The analytical method was validated for concentrations ranging from 3.82-45.84 μg/mL with acceptable accuracy, precision, and recovery. Overall, the UA levels of Mn exposure samples were significantly lower than that of control samples (P<0.05).</p><p><b>CONCLUSION</b>The practical method developed here is suitable for both routine monitoring of UA level in human urine and metabolism research. Long-term and low-level occupational Mn exposure may lead to a lower UA level in urine, and UA might be an indicator of the early stage of manganism.</p>
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Chromatography, High Pressure Liquid , Manganese , Occupational Exposure , Sex Factors , Uric Acid , UrineABSTRACT
Objective:To study the optimum ethanol extraction process. Methods: The extraction rate of extractum and total flavonoids as well scutellarin was choosen as the assessment index. The optimum ethanol extraction process was selected with the orthogonal design. Results: The optimum ethanol extraction process conditions follow as: adding 10 fold of 75% ethanol, extracting for 2.0h and twice in all. Conclusion: The average extraction rate of extractum and total flavonoids as well scutellarin was 13.6%, 91.7%, 78.4%(n=3), respectively.