Differences between the chemical constituents of tincture and Arishta, an ayurvedic herbal liquor prepared from ginger, long pepper, and jujube

Abstract

In Ayurveda, practitioners use a herbal liquor called Arishta to treat patients suffering with emaciation or indigestion. Arishta is produced by decocting various herbs and then subjecting the resultant liquid to alcoholic fermentation. During the alcoholic fermentation stage, the constituents of Arishta change chemically, which would also alter the medicinal effects of Arishta. In order to characterize the components of Arishta, we investigated the differences between the compositions of Arishta and a tincture (an alcohol-soaked herbal liquor). First, we attempted to prepare Arishta in our laboratory from ginger, jujube, and long pepper and compared the piperine and [6]-gingerol contents of Arishta with those of the abovementioned tincture using HPLC. The alcohol content of the laboratory-made Arishta (LM-Arishta) was 15%, which was almost the same as that of the Arishta sold in Sri Lanka. The piperine content of the LM-Arishta was 14.6 mg/l, which was slightly higher than that of the tincture. It seems that decoction is more effective way to extract piperine than ethanol immersion. However, [6]-gingerol content of the LM-Arishta was 11.3 mg/l, which was less than 50% of that of the tincture. Subsequently, we incubated [6]-gingerol with yeast in culture medium to search [6]-gingerol metabolites. LC-MS/MS analysis suggested that [6]-gingerol is transformed to 4 metabolites such as [6]-shogaol and 3 or 5 acetoxy-[6]-gingerdiol during alcoholic fermentation. These metabolites were also detected in LM-Arishta and thus, it was suggested that [6]-gingerol was metabolized during LM-Arishta making.