Study On The Extraction And Refining Technics Of Natural Active Components From Rosemary And Determination Of Antioxidative Activity

The purpose of the present study is to implement comprehensive development and utilization of rosemary, using rosmary planted in Zhejiang Province as main raw material. Isolating and purifying water-soluble and liposoluble antioxidant components from rosemary that enssential oils has been extracted, and preliminarily refining rosemary essential oil. In addition, determining antioxygenic property of purified product by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. The main research contents were as follows:1. Five extraction methods of essential oils were comprehensively compared, including water distillation,steam distillation and simultaneous distillation and extraction, etc. The results show that essential oils yield was distributed between 1.50 mL/100g and 1.60 mL/100g for five methods. Among them, water distillation and solvent-free microwave extraction had relatively higher yield. From aspect of extraction time, steam distillation and solvent-free microwave extraction need to spend about one hour, less than the other methods.It was also found that solvent-free microwave extraction showed a good pretreatment effect. Rosemary leaves that essential oils been extracted by microwave extraction, the three kinds of main antioxidative substance, carnosic acids carnosol and rosmarinic acid contents can be reserved for a longer time. Whereas the no-pretreatment fresh leaves' carnosic acid,carnosol and rosmarinic acid contents reduced significantly after storing for about ten days. This shows that solvent-free microwave extraction is not only in short time and high efficiency, but also can be used as a kind of new pretreatment method of storing fresh material.2. A reliable and stable method is established to determine the content of total phenolic acids of rosemary by Folin-Ciocalteu colorimetry. The appropriate detection conditions were : ratio between the volume of Folin-Ciocalteu reagent and 10% Na₂CO₃ was 1:3 (v:v); the volume of Folin-Ciocalteu reagent was 1.5 mL; reaction temperature was 25℃; reaction time was 2 h; the detection wavelength was 765 nm.3. H1020 resin was screened out from 9 kinds of macroporous resin,and it was the optimum macroporous resin to purify liposoluble total phenolic acids from rosemary. The results showed adsorption mode of H1020 resin belong to S style, sample concentration have a great influence on adsorption efficiency. The flow rate was 1mL/min when the concentration of rosemary total phenolic acids was 4.45mg/mL, After dynamic purification, the liposoluble total phenolic acids mass fraction increased from 47.74% to 70.46%, and its IC₅₀ value on scavenging DPPH radical was 0.0469 mg/mL, it was close to BHT.4. Study on the purification of rosmarinic acid from rosemary by macroporous resin. The results showed HPD-200L resin is a suitable material. Saturated adsorption capacity of HPD- 200L resin was 25.27 mg/g (dry resin), saturated absorption time was 3 h, suitable desorption agent was 60% (volume fraction) ethanol solution, under the conditions of 20℃and pH 2-3, the flow rate was 1 mL/min when the concentration of rosmarinic acid was 0.8 mg/mL. After dynamic purification, the hydrosoluble rosmarinic acid mass fraction increased from 7.98% to 36.8%, and its IC₅₀ value on scavenging DPPH radical was 0.0262 mg/mL, it was superior to BHT.5. Preliminarily refine rosemary essential oil by vacuum batch distillation. The results showed acquired product reached the expected objective when system vacuum pressure was -0.095 MPa, using mode of changing reflux ratio and collecting different temperature section product. To obtain several product which content ofα-pinene,1,8-cineole and camphor reached to 88.17%,77.45% and 78.82% respectively. Research on antioxidative activity showed heavy oil has a better effect than others, therefore heavy oil fraction that is usually considered as discard raffinate will have a good prospect of research and application.