Research progress of extraction method and biological activity of natural citral

Citral,a kind of monoterpene compound,existed in leaves and fruits of many plants and was main component of aromatic plant essential oils. Because of its unique aroma components,citral gained popularity and was widely used in spice and fragrance manufacturing and beauty industry. This paper summarized citral extraction methods(distillation,supercritical CO₂ extraction,microwave technology,chemical extraction and phase transfer catalyst methods),and compared their advantages and disadvantages. Because citral was unstable and easy to degrade,methods of reducing storage temperature,changing p H,changing oxygen concentration,using antioxidants,oil-in-water emulsion and microcapsule technology were commonly used to slow down the degradation of citral. Bioactivity of citral was diverse,therefore citral had antibacterial activity,anti-inflammatory activity,antitumor activity and antioxidant activity,at the same time citral could be used to kill insects,repel mosquitoes,treat diabetes and cardiovascular diseases,relieve asthma and cough as an ingredient of anticancer drugs. In this paper,it is suggested that the research should be strengthened in the future from the aspects of optimizing the extraction process of natural citral,increasing the stability of citral,developing new drugs of citral and products of citral derivatives,in order to better develop and utilize citral.