Extraction Of Active Components From Antler Velvet And Preparation Of A Novel Microcapsule

Antler velvet has been used in traditional Chinese medicines for over two thousand years. It has long been recognized as one of the most effective and powerful invigorants for strengthening the kidney, sexual-reinforcing, and prolonging life. Many substances from antler velvet were identified and claimed to contain active components, including unsaturated fatty acid, hypoxanthine, p-hydroxybenzaldehyde, phospholipids, cholesterol, estrogen and progesterone, insulin-like growth factorâ… (IGF-1) and growth factor(GH), etc. Now the processing mode of antler velvet is lagged, and the product species is very limited. In order to widen the application space of antler in the future and improve its added value, three group of active components whose act are certain and vital in clinic were extracted from antler in this paper by supercritical fluid extraction, ultrasound-assisted extraction and other separating technologies for protein. They were monoamine oxidase (MAO) inhibitor, natural estrogen and insulin-like growth factor1(IGF-1). The solubility of PHBD standard in supercritical carbon dioxide (SC-CO₂) was determined by using a flow apparatus. The feasibility of preparing microcapsule with dried yeast (S. cerevisiae) cell as wall materials was studied.First, The MAO inhibitor was extracted by supercritical CO₂ from boiled-dry antler velvet powder. The effects of particle size, kinds of co-solvent, extraction temperature and pressure on the extraction yield and the total inhibition activity on MAO-B in vitro (TI) were investigated. The experimental results show that the extraction yield can reach 3.58% and the TI of the extract is 3319.13 U/g. The extracts of antler velvet by supercritical fluid (EAS) inhibit the MAO-B activity in a does-dependent manner, but have slight effect on MAO-A. The activity of MAO-B and MAO-A were inhibited by 93.77% and 24.18% respectively at 278.15 mg/L EAS solution. The chemical composition of EAS was analyzed by HPLC, TLC, GC-MS, GC and radioimmunoassay(RIA). The analytical results show that hypoxanthine, p-hydroxybenzaldehyde and phospholipids, which were reported to have inhibitory activities on MAO, were identified from EAS. Besides, some other active substance was detected in the EAS, including unsaturated fatty acid, sitosterol, cholesterol, vitamin E, steroids, estradiol, testosterone and progesterone, etc.In other side, the natural estrogen was extracted and concentrated from boiled-dry antler velvet by supercritical fluid extraction. The extraction yield of estradiol can reach 0.3342 ng/g antler. The content of estradiol and progesterone in the EAS are 48.42 ng/g and 197.04 ng/g respectively. The extract would be developed to functional products or medicine for guarding against and treating the women's menopause syndrome.The IGF-1 was extracted from fresh antler velvet by ultrasound-assisted extraction. The No.1 buffer was selected as extraction solution.,and the extraction yield of IGF-1 can reach 5279.29 ng/g. The results show that ultrasound-assisted extraction is simple and efficient. The crude extract solution of IGF-1 was concentrated to 6～10 times by ultrafiltration with 10.0 kDa membrane. The loss of IGF-1 is only 2.49%. The ultrafiltration process was accomplished in short time. By utilizing absolute ethyl alcohol precipitation, the removal of other protein is 91.59%, the loss of IGF-1 is 24.52%, and the IGF-1 content in total protein extracted from antler velvet was raised 8.97 times. Crude extract of IGF-1 was elementarily purified by ion exchange chromatography. The IGF-1 content in total protein is raised 12.01 times. The recovery of IGF-1 and total proteins are 91.73% and 66.85% respectively. The IGF-1 in the extract from fresh antler velvet was observed and identified by SDS-PAGE and high performance capillary electrophoresis (HPCE). The results show that there contains IGF-1 in the crude extract. Growth hormone(GH) was detected in the crude extract of IGF-1 from fresh antler by RIA.Firstly, the monoamine inhibitor was extracted from lyophylization powder of antler velvet by supercritical carbon dioxide. Then the polypeptide including IGF-1 was separated from the remainder of SFE by solvent extraction. The experimental results show that it is feasible to combine to extract some liposoluble active substance and IGF-1 from antler velvet.The solubility of p-hydroxybenzaldehyde in supercritical carbon dioxide was determined by using a continuous flow apparatus. The experimental datas were correlated with two empirical equations and give letter agreement. In the end, the solubility of p-hydroxybenzaldehyde was predicated by Peng-Ronbison EOS. A novel microcapsule was prepared with dried yeast (S. cerevisiae) cell as wall materials, and the clove bud oil (CBO) and methyl salicylate(MS)were selected as core materials. The effects of encapsulating temperature, the ratio of core material to yeast and encapsulating time on the microencapsulation were investigated. The experimental results show that the yield of CBO encapsulated in microcapsule can reach 41.26%, and the yield of encapsulated MS can reach 48.58%. The morphology of the microcapsule is global observed by optical microscope and scanning electron microscope(SEM), and the particle diameter is 2.0～4.0μm. By means of utilizing the dried yeast cell as wall materials, the microencapsulation process is simple and efficient and is free of using organic solvent.