Optimization of Extraction Technology and Biological Activities of Liposoluble Components from Nerium indicum Mill. Flower

OBJECTIVE To study the extraction process, composition and biological activity of liposoluble components from Nerium indicum Mill. flower. METHODS Box-Behnken response surface methodology was used to optimize the extraction technology of liposoluble components, and the chemical compositions were studied by GC-MS. The antibacterial activity was determined by paper diffusion method and double continuous gradient dilution method, while study the antioxidant activity. RESULTS The results of optimum extraction condition were as follows:Extraction duration 4 h, 4 times of extraction, and the solid-liquid ratio 1:15, the actual value of the yield was 9.16%, which increased by 13.09% compared with the initial extraction conditions. There were 30 compounds including alkanes, aldehydes and esters in liposoluble components. The liposoluble components had the reduction ability and scavenging ability of DPPH radicals, hydroxyl radicals and superoxide anion radicals. The minimum inhibitory concentration of liposoluble components on Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were 1.22, 1.72, 0.75, 1.96 g·L^–1, respectively. The minimum bactericidal concentration were 2.34, 2.84, 1.88, 3.32 g·L^–1, respectively. CONCLUSION Actual value of optimized extraction technology is 9.16%, the composition of liposoluble components from Nerium indicum Mill. flower mainly include alkanes, aldehydes and esters, and have certain antioxidant activity and antibacterial activity, which can provide reference for the development and utilization of Nerium indicum Mill. resources.