Study On The Extraction And Purification Of Reed Leave Flavonoids And Its Antioxidants

Reed has the feature of strong growth ability and large distribution area and is mainly applied to the papermaking, building, greening, and environment protection. However, the economical substances of reed especially reed leaves were rarely studied before.The flavonoids were widly existed as a kind of natural antioxiants. They also exerted a number of physical-chemical functions such as lowering blood pressure, decreasing serum lipids, cancer-depressed and etc. Now, many kinds of plant flavonoids have been studied at home and abroad, but the research on reed leaves flavonoids has rarely reported yet.The extraction technology, purification technology and antioxidation of the reed leaves flavonoids were studied on this paper.(1) The research on the extraction technology of reed leaves flavonoids.Ethanol as solvent, the ultrasonic wave extraction technology and the enzymolysis extraction were optimized and compared with the soxhlet extraction. The result show that the two extraction technologies both had better extractive yields than their controls, expecially the ultrasonic wave extraction technology. The major parameters of it were 70 % ethanol as extractant, 1:50 of material to extractant, immersion for 24h, and ultrasonic wave extraction for 50min at 70℃.(2)The research on the purification technology of crude extracts of reed leaves. One of the eight microporous resins which has better purification effect on reed leave flavonoids was selected on the paper. Subsequently, the purification parameters of the microporous resin were studied. Result shows that HZ818 has better purification effect, The major parameters of the absorption parameters are adsorption velocity1.6-2.4 mL·min-1, pH 3 and the optimal desorption parameters are 70% ehanol as eluting solvent, pH 8, the desorption velocity 3.0 mL·min-1, the cubage of eluant 5BV.(3)The research of the antioxidation of reed leaves flavonoids.Taking crude extraction and purified extraction as the raw material, the total antioxidation, DPPH·scavenging ability and activity of restraining lard oxidation were tested on this paper. Results are as follows.①The purified extraction have better effect on DPPH·scavenging than the crude extraction while the crude extraction is better than the control.②On the condition of same content of total flavonoids, the total antioxidation capability of purified extraction is significantly higher than crude extraction.③The crude extraction and the purifed extraction both have the inhibiting effect on the lard oxidation and the much more amout of them, the better effect.(4)Some preliminary research on the components of reed leaves flavonoids.The TLC and silica gel column chromatography on the puried extraction were studied and tested by HPLC. Results are as follows①Methanol: Acetic acid: Water (18:1:1) has better effect than the other 12 developing sovent on the polyamide thin layer chromatography of reed leaves flavonoids and has 7 separation points on it. This means that the reed leaves flavonoids have 7 kinds of components at least.②The determination of HPLC shows that the purified extraction has the highest level of rutin content and reaches to 3.03%.③Through the UV and TLC testing, the silica gel column chromatography could separate the purified extraction into 5 parts. The determination of HPLC shows the first part may contain isoflavones or flavanone. The third and fouth part have 2 or 3 kinds of flavonoids and rutin is mainly existed on the fourth part.