Extraction Of The Alkaloids From Urtica Angstifolia

Urtica angustifolia is an annual or perennial and can be medicine, edible traditional wild herbaceous herbs. It was recorded in Tu Jing Ben Cao firstly, had a long medicinal history, such as:detoxification, Wind-dispelling dehumidification and anti-inflammatory analgesic efficacy. In this paper, the active ingredient in Urtica angustifolia was analyzed systematically. Saponins, polysaccharides, alkaloids, flavonoids and other active ingredients in Urtica angustifolia were confirmed. Alkaloids of its rhizome were extracted, separated and purificated and structure elucidated. We also studied the antibacterial effects of the alkaloids.First determined a extraction method for extraction the alkaloid from Urtica angustifolia, then did Single-factor experiment and processed Data by response surface method(RSM). The optimal extraction conditions were:ultrasonic extraction time10min, ratio of the material-liquid1:10(g/ml), ethanol concentration85%, extraction time2hour. Total alkaloids yield1.0747%.Secondly, alkaloids were purified by petroleum ether extract3times. put the extraction into the AB-8Resin for elute. The optimal conditions for purification:0.6876%of the initial concentration of alkaloids in crude extracts the amount of160ml Alkaloids on the sample volume was160ml, The best eluent was320ml40%ethanol, then extracted use silica gel column chromatography with chloroform:methanol:water (4:3:2) elution. After drying the organic solvent, get light yellow powder of narrow-leaf nettle alkaloids.The alkaloids’UV spectral absorption peak at277nm, accorded to infrared spectroscopy functional group’s absorption characteristics, the extraction was alkaloid, compared with standard incarvillea resin base’s high performance liquid chromatography and mass spectrometry, confirmed the narrow leaf nettle alkaloids was a component of incarvillea alkaloids. The positive ion scan m/z was184.The antibacterial effect of narrow-leaf nettle alkaloids also be investigated, the result indicated that alkaloids of urtica angustifolia had significant inhibitory effect to E. coli, Staphylococcus aureus, Proteus, Streptococcus thermophilus, Bacillus subtilis. The minimum inhibitory concentration of each species were:5mg/ml,20mg/ml,40mg/ml,80mg/ml,5mg/ml.