ABSTRACT
Olive oil is one of the important byproducts in agriculture. It is rich in oleuropein, which can be hydrolyzed into several bioactive phenolic compounds, including hydroxytyrosol (HT).There are many literatures have been confirmed that HT has significant pharmacological effects in the anti-inflammatory, anti-virus, regulation of metabolic disorders and treatment of degenerative diseases. However, HT has severe instability in vivo and in vitro. It is a challenge how to improve its stability through structural transformation or utilization of pharmaceutical means to processing. This paper will focus on biological activity of HT and its stability improvement, and provid some new ideas for expanding the research and promoting the development of HT in the field of Medicine.
ABSTRACT
A liquid chromatography_tandem mass spectrometric method was established for the determination of 25 kinds of veterinary antibiotics in manure, soil and water by ultrasonic_solid phase extraction. Purification efficiency of SAX cartridges for soil and manure samples extract and the procedure that manure samples defatted with hexane was also verified. The results showed that the average recoveries of the 25 target antibiotics were 50. 0%-121. 9%, the relative standard deviations (RSD) were 1. 1%-14. 71% (n=9), and the limits of detection (LOD) ranged from 0. 0002-0. 0560 μg/kg for soil and manure and ranged from 0. 002-0. 28 ng/L for water; After adding SAX cartridges, the matrix effects of manure samples reduced to 55%-120%, and soil samples to 75%-160%; after defatting by hexane extraction, the matrix effects of manure sample reduced to 55%-120%. This method has been employed to detect the veterinary antibiotics in environmental samples of livestock farm.
ABSTRACT
[Objective]To establish a method to determine the contents of glucase and fructose in extracts of leaves of Lonicera hypoglauca Miq. using HPLC-ELSD, and apply this method to study the content change of glucose and fructose in different solvents extracts in leaves of Lonicera hypoglauca Miq. [Methods] The chromatographic separation was achieved on Lichrospher NH2 column using a mobile phase composed of a mixture of acetonitrile and water(90:10) at a flow rate of 0.8mL·min-1 and the column temperature was 25℃.The ELSD drift tube temperature was set at 70℃ and the carrying gas was N2 and the flow rate of the gas was 1.6L·min-1. [Results] Glucose and fructose from extracts of the leaves of Lonicera hypoglauca Miq. could be wel separated, and the linearity ranges of glucose and fructose were shown at the concentration of 0.5840~1.168mg·mL-1 and 0.8256~1.8576mg·mL-1, the average recovery rate of glucose and fructose were 96.88%(RSD=1.11%) and 97.55%(RSD=1.15%), the stability of glucose and fructose was 2.12%and 0.38%, and the repeatability was 1.31% and 0.24%. Among the water extract,50% alcohol extract and 95% alcohol extract,the content of the glucose and fructose in the water extract was highest,which was 2.19mg·mL and 4.10mg·mL-1, the 50% alcohol extract was second, which was 1.13mg·mL-1 and 2.12mg·mL-1, and the 95% alcohol extract was lowest, which was 0.45mg·mL-1 and 0.65mg·mL-1.[Conclusion] The method is simple, accurate and has good repeatability, and can be used to determine the contents of glucose and fructose in the extract of leaves of Lonicera hypoglauca Miq. In this batch of leaves of Lonicera hypoglauca Miq., the contents of fructose and glucose were of water extract>50%ethanol extract>95%ethanol extract.