10 kilos of dried whole jaborandi leaves were placedin a conventional percolator. The leaves were then extracted two times, each time with 50 liters of a 3%aqueous hydrochloric acid solution. It was determinedthat 100% of the pilocarpine were extracted from thejaborandi leaves by analysis of the alkaloid content of theexhausted leaves. The extracts were combined and neutralized to a pH of between 7 and 8 with a concentratedammonium hydroxide solution.500 grams of activated carbon were added to the neutralized solution and the mixture was gently stirred forabout three hours. Thereafter, the mixture was allowedto settle and the supernatant liquid was decanted. Thecarbon absorbate residue was ?ltered on a vacuum ?lterand washed with two one-liter aliquots of water having a pH of 7.5.The moist carbon absorbate was then mixed with oneliter of ethyl alcohol, drained, and again eluted with one liter of ethyl alcohol and drained. The extracts were combined and concentrated under vacuum. A mixture of 3portions of ethanol to one portion of 6 M nitric acid wasadded dropwise until a pH of 5 to 7 was achieved. Thesolution was again concentrated to one-third its originalvolume and placed in the refrigerator overnight. Rawcrystalline pilocarpine nitrate was separated by ?ltrationand purified by recrystallization from ethyl alcohol. Yieldsof 80% to 100% of pilocarpine nitrate were recoveredbased on the pilocarpine content of the jaborandi levaes.
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