Ornithine alkaloid in alhagi sparsifolia as well as extraction method and application of ornithine alkaloid

The invention relates to the technical field of separation and purification of alhagi sparsifolia, in particular to ornithine alkaloid in alhagi sparsifolia as well as an extraction method and application thereof.The extraction method comprises the following steps: crushing the overground part of dry alhagi sparsifolia, adding methanol, performing heating reflux extraction, dispersing the obtained total extract of alhagi sparsifolia with water, performing extraction and concentration with petroleum ether, ethyl acetate and dichloromethane, and obtaining ornithine alkaloid in alhagi sparsifolia; performing gradient elution separation on the dichloromethane part extract by silica gel column chromatography, performing gradient elution on the fifth fraction by high performance liquid chromatography, purifying and separating, and collecting the eluate, thereby obtaining the ornithine alkaloid in the alhagi sparsifolia in 7.3 minutes. The invention discloses 2-methylhexahydro-3H-pyrrolo [1, 2-a] idazol-3-one in alh