Preparation And Antioxidative Activity Evaluation Of Osmanthus Essential Oil Nanoemulsion

Objective: This paper intends to embed osmanthus essential oil with nanoemul sion made of Bletilla striata polysaccharide as emulsifier and active ingredient,to explore the stability,safety and antioxidant effect of osmanthus essential oil nanoem-ulsion in order to be stable,effective,whitening and anti-aging Effect provides high-value-added product development provides a theoretical basis.Methods: Combined with single-factor screening,the extraction rate of Bletilla striata polysaccharides was used as the investigation index,and the extraction proces-s of Bletilla striata polysaccharides was optimized by ultrasound-assisted water extr-action and alcohol precipitation.Use pseudo-ternary phase diagram to screen the em-ulsifier(the best ratio of Bletilla striata polysaccharide to poloxamer 188),co-emuls-ifier,oil phase and water phase and the mass ratio of emulsifier to co-emulsifier(Km value).According to the design principle of Box-Benhnken central combination exp eriment,the three-factor three-level response surface analysis method was used to op-timize the prescription and process of osmanthus essential oil nanoemulsion.The st-ability of osmanthus essential oil nanoemulsion was evaluated initially through acce-lerated experiments,long-term experiments,and light experiments;the safety of os-manthus essential oil nanoemulsion was studied initially through cytotoxicity experi ments and cell hemolysis experiments;the DPPH(1,1-Diphenyl-2-trinitrophenylhyd-razine)scavenging ability of free radicals to evaluate the antioxidant activity of osmanthus essential oil nanoemulsion and Bletilla striata polysaccharide.Results: Ultrasonic-assisted water extraction and alcohol precipitation to extrac-t the best process conditions of Bletilla striata: water-to-material ratio 1:50(g / mL),extraction temperature 80?,extraction time 4 h,ultrasonic power 150 W,ethanol co-ncentration 70%,3 Double volume of ethanol(V / V),alc ohol precipitation time 2 h,the extraction rate of Bletilla striata polysaccharide was 31.32%.The optimal ratio of Bletilla striata polysaccharide to poloxamer 188 was 1: 2,the co-surfactant was gl-ycerin,the oil phase was soybean oil,and the Km value was 3.Under these conditio-s,the particle size of e microemulsion was(218.9±4.1)nm,the polydispersity coeffi cient was(0.228±0.032),and the particle size distribution was uniform.The volume ratio of the oil-water phase was 5,the ultrasonic power was 70%,and the input amou unt of osmanthus essential oil was 18 ?L.High-performance liquid detection results showed that the concentration of osmanthus essential oil in the range of 196.92-4923.20 ?g / mL had a good linear relationship with the peak area,precision RSD = 0.91%,reproducibility RSD = 1.42%,and high sample recovery rate.Stable experim ments showed that osmanthus essential oil nanoemulsion had good photostability,no delamination and precipitation,as well as demulsification under centrifugal experim-ents and long-term experiments.The results of cytotoxicity experiments showed tha-t compared with the control group,osmanthus essential oil nanoemulsion had little t-oxicity on the viability of cardiomyocytes within the detected concentration range.The results of red blood cell hemolysis test showed the same as results of cytotoxicit-y test,and osmanthus essential oil nanoemulsion had a weak hemolytic effect on red blood cells,low toxicity and good biological safety.In addition,the results also proved that osmanthus essential oil nanoemulsion showed elevated scavenging ability against DPPH with the increased concentration of Bletilla polysaccharide and osmanthus essential oil in the samples to be tested,indicating that the ability of the samples to scavenge DPPH free radical was positively correlated with the mass concentration of Bletilla striata polysaccharide and osmanthus essential oil.The osmanthus essential oil and osmanths essential oil nanoemulsions at the same concentration have a relatively enhanced scavenging ability to DPPH free radical,which indicates that the osmanthus essential oil nanoemulsion retains the original antioxidant activity during the preparation process.Forthermore,the results also showed that osmanthus essential oil and Bletilla striata polysaccharide seem to have a certain synergistic effect in antioxidation.Conclusion: Bletilla striata polysaccharide can be used as a surfactant and nanometer material.Osmanthus essential oil nanoemulsion has good stability,safety,and has a certain antioxidant effect,which may be develop a stable,effective daily chemical product with skin whitening and anti-aging activities.