Sunflower seed oil containing ginseng stem-leaf saponins (E515-D) is a safe adjuvant for Newcastle disease vaccine

Abstract Vaccination is an effective method to prevent Newcastle disease (ND) in chickens. Marcol 52 and #10 white oil are mineral based adjuvants and can be found in commercial inactivated NDV vaccines. The present study demonstrated that a vegetable origin oil E515-D had lower polycyclic aromatic hydrocarbons (PAHs) and higher flash point than the commercial products Marcol 52 and #10 white oil. E515-D could be mixed with an aqueous phase containing NDV antigen to form a stable W/O vaccine emulsion and exhibited more potent adjuvant effect on the immune response than Marcol 52 and #10 white oil. Moreover, the absorption of E515-D-adjuvanted vaccine was faster than Marcol 52- and #10 white oil-adjuvanted vaccines when NDV vaccines were injected in broilers. Therefore, E515-D was safe and could be a suitable adjuvant used in vaccines for food animals. In addition，E515-D is not easy to be flammable during shipping and storage due to its higher flash point.