High purity alpha yohimbine (rauwolscine) from rauwolfia species

Abstract

Present invention discloses a novel, commercially viable process for extraction of Alpha yohimbine from the bark, stem and leaves of Rauwolfia species. The extract is obtained by a precipitation method involving alternate steps of acidification and alkalization along with use of specific organic solvents. The extract gives higher yield of 7-8 fold as compared to other processes and without use of any column chromatography at all. Yield of alpha yohimbine from roots and leaves of Rauwolfia canescens by process of present invention was 0.017% and 0.4% respectively, indicating that leaves are a much better source. The HPLC analysis of the compound obtained indicated a purity of >90%.

Description

[0001]The present invention relates to natural extracts / herbal extracts More specifically, it pertains to a novel process for the extraction of alpha yohimbine (rauwolscine) from Rauwolfia species. The process gives alpha yohimbine in significantly higher quantity and purity as compared to prior art methods.BACKGROUND OF THE INVENTION[0002]Terms and Definitions[0003]Alkaloids—These are a group of naturally occurring chemical compounds that mostly contain basic nitrogen atoms (https: / / en.wikipedia.org / wiki / Alkaloid). They are of plant origin and have pronounced physiological actions on humans. They include many drugs (morphine, quinine) and poisons (atropine, strychnine).[0004]Phytochemicals—These are compounds derived from plants.[0005]Organic solvents—Organic solvents are a chemical class of compounds that share a common structure (at least 1 carbon atom and 1 hydrogen atom), low molecular weight, lipophilicity, and volatility, and they exist in liquid form at room temperature. The...

AI Technical Summary

Benefits of technology

[0045]One more object of the present invention is to disclose use of renewable source i.e. leaves of a specific species of Rauwolfia i.e. Rauwolfia canescens, as a raw material instead of bark, because it contains higher % of the active compound, resulting in higher yield.

Problems solved by technology

The methodology is complex involving multiple fractionation techniques involving use of organic solvents, acidification and basification and also use of column chromatography (flash chromatography) to fracionate alpha yohimbine from other compounds The method is more of a laboratory scale method for isolation and purification of alkaloid compounds from Rauwolfia sp. for research purposes, than a process for commercial scale production of alpha yohimbine.

Prior art methods have used column chromatography and expensive matrices to purify alpha-yohimbine.

Column chromatography reduces yields and enhances the cost of extraction, making it unviable for extraction and purification of compounds at commercial scale, though it is very much suitable for laboratory scale preparation.

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