The preliminary phytochemical investigation showed the presence of alkaloids, tannins, carbohydrates, proteins, fixed oils in methanolic extracts of raw and purified seeds. The glycoside loganin, which was present in raw seeds was found to be absent in the purified seeds. The presence of strychnine and brucine was confirmed by comparing the Rf values with those of the standard markers by HPTLC.
It was also observed that 54.20 and 66.30% of purified Kupeelu was obtained after purification in Kanji and Ardraka swarasa, respectively [Tables and ]. The moisture content in Kupeelu was increased after purification with Kanji, but decreased when the seeds were processed in Ardraka swarasa . The water-soluble and alcohol-soluble extractive values were decreased in both the samples after purification . Water and alcohol-soluble extractive values in Kanji purified seeds were comparatively less than those in the Ardraka swarasa purified samples. Therefore, better extraction of alkaloids, along with other chemical constituents, took place when the raw samples were kept in Kanji. However, reduction in the alkaloid content like strychnine and brucine was only observed when the samples were processed in Ardraka swarasa. Therefore, a hypothesis can be drawn that as far as reduction in concentrations of toxic alkaloids are concerned either by extraction or by transformation into another form Ardraka swarasa may be a better media than Kanji.
Effect of Shodhana (purification) by Kanji on the yield of the final products and organoleptic characters
Effect of Shodhana (purification) by Ardraka swarasa on the yield of the final products and organoleptic characters
Physicochemical parameters of raw and purified seeds
Kanji (pH 3.4) being acidic in nature may facilitate the extraction of alkaloids like strychnine and brucine, along with other chemical constituents from nux vomica seeds. Thus, it may be assumed that Kanji is a better extraction media than Ardraka swarasa.
In the HPTLC chromatogram, the UV spectrum of standard strychnine (Rf 0.54) at 254 nm and standard brucine (Rf 0.34) [Figures and ], and the peak areas of strychnine and brucine in all the samples are exposed [Figures –]. Calibration curves of strychnine and brucine were prepared by plotting concentrations of strychnine and brucine in the range of 2–6 μg / spot versus average area of the peak. The responses for concentrations of standard strychnine and brucine were found to be linear [Figures and ]. The amount of strychnine and brucine in the raw and purified samples were computed from the calibration curves, which suggested that the highest reduction of strychnine and brucine was found in the Ardraka swarasa purified samples . It might be due to the fact that prolonged contact of the seeds with Ardraka swarasa not only helped to diffuse out some quantity of the alkaloids from the seeds, but also some amount of strychnine and brucine might have been converted into less toxic derivatives like isostrychnine, isobrucine, strychnine N-oxide, brucine N-oxide, and so on.
HPTLC profile of standard strychnine
HPTLC profile of standard brucine
HPTLC of raw Kupeelushowing peak areas of strychnine and brucine
PHPTLC of Kupeelu purified by Ardraka swarasa showing peak areas of strychnine and brucine
Results of estimation of strychnine and brucine in raw and purified samples of Kupeelu by HPTLC
HPTLC of Kupeelu purified by Kanji showing peak areas of strychnine and brucine