RESUMO
OBJECTIVE: To establish an extraction method of hirudin by double aqueous phase combined with gel chromatography. METHODS: Anti-thrombin activity units (ATU) was adopted as the index. On the basis of optimizing the double aqueous phase extraction conditions, a new extraction technology of hirudin was established by employing double aqueous phase system combined with gel chromatography. The double aqueous phase was composed of polyethylene glycol and ammonium sulfate and took the digestive juice of Poecilobdella manillensis from Guangxi Province as the raw material. RESULTS: In the studied experimental range, the optimum technological conditions of double aqueous phase extraction of hirudin reference substantce were as follows: the contents of PEG 2000, (NH4)2SO4 and NaCl were 22%, 20% and 0.04%, respectively. The extraction temperature was 35°C, and pH was 6.0. The obtained extracts were further purified by gel chromatography. The recoveries of ATU reached 81.92%, 80.34% and 80.36% for hirudin reference substance, hirudin crude extracts and scale-up experiment, respectively. The specific activity of obtained products reached 3210.27 ATU · mg-1. The results of discontinuous polyacrylate gel electrophoresis and spectral scan for the extract were the same with for the reference substance. CONCLUSION: The double aqueous phase extraction combined with gel chromatography is good for hirudin. Copyright 2012 by the Chinese Pharmaceutical Association.
RESUMO
<p><b>OBJECTIVE</b>To study the extraction system of hirudin emulsion liquid membrane with the Poecilobdella manillensis as raw material, di-(2-ethylhexyl) phosphate (D2EHPA) as carrier, Span 80 as emulsifier, octane and D2EHPA mixed to constitute membrane solution, diluted HCl solutions as internal aqueous phase.</p><p><b>METHOD</b>Using the orthogonal experiment to optimize the extraction conditions of hirudin reference substance such as membrane phase, internal aqueous phase volume ratio (MIPVR), external aqueous phase pH, internal aqueous phase pH, mobile carrier concentration and so on, and then using hirudin crude extracts to do purifying experiment, and gaining experimental samples.</p><p><b>RESULT</b>The optimal conditions of hirudin extraction were as follows: MIPVR 10: 3, internal aqueous phase pH 2.6, external aqueous phase pH 3.4, the mass fraction of carrier D2EHPA 2%. In the optimal extraction conditions, when the initial concentration of hirudin was one anti-thrombin activity units (ATU) x mL(-1), ATU recovery rate of the reference substance was 83.06%. In the purifying experiment of crude extracts, ATU recovery rate was 82.99%, and the specific activity of sample was 3 289.48 the ATU x mg(-1). Discontinuous polyacrylamide gel electrophoresis and spectral scanning, the results showed that the purity and reference substance were considerable.</p><p><b>CONCLUSION</b>The method of preparation hirudin was relatively simple, the purity of the experimental samples and ATU recovery were both high.</p>