Analysis of constituents from different parts of Rhodomyrtus tomentosa by HPLC-TOF-MS / 中草药

Objective To compare chemical composition in the different parts (leaf, branch, and fruit) of Rhodomyrtus tomentosa, and to study the chemical constituents from fruits of R. tomentosa. Methods High performance liquid chromatography/time-of-flight mass spectrometry (HPLC-TOF-MS) method was executed to analyze the samples. Principle component analysis (PCA) and partial minimum variance discriminant analysis (OPLS-DA) in MassLynx XS software were used to analyze the obtained data. The chemical constituents of fruits were isolated and purified by column chromatography, including silica gel, Sephedex LH-20 and re-HPLC, and the structures were elucidated based on their NMR and MS data. Results The PCA results indicated that the constituents existed in leaf were significantly different from those in branch and fruit, while constituents in branch and fruit were similar. Furthermore, based on OPLS-DA, combined with chromatographic retention regulation, accurate molecular mass, isotopic matching and literature searching, four marker compounds from leaves had been found and identified as myricitrin (1), myricitrin-3-O-L-furanoarabinoside (2), iridin (3), and 3,3’-didemethyl-9-oxo-pinoresinol (4). Besides, five compounds were isolated from fruits and identified as maslinic acid (5), ethyl gallate (6), gallic acid (7), resveratrol (8), and piceatannol (9). Conclusion This research provides an effective strategy for analyzing chemical difference from different parts of R. tomentosa, which can be applied to study the chemical difference from different parts of other species.

Validated high performance thin layer chromatography method for the quantification of bioactive marker compounds in Draksharishta, an ayurvedic polyherbal formulation

ABSTRACT Draksharishta is an ayurvedic polyherbal formulation with Draksha (Vitis vinifera L., Vitaceae) as chief ingredient prescribed for digestive impairment, respiratory disorders and weakness. These herbal medicines containing biologically active compounds play a significant role. Therefore it is necessary to carry out the chemical standardization of bioactive marker compounds present in the polyherbal ayurvedic formulation like Draksharishta. The aim of the present work was to develop and validate a HPTLC method for determination of gallic acid, catechin and resveratrol in commercially available marketed and in-house prepared formulations of Draksharishta. This is the first report of quantification of bioactive marker compound resveratrol using HPTLC in Draksharishta. The method employed silica gel precoated thin layer chromatography plates with F254 as the stationary phase. The respective mobile phases were used to develop the plates which separated bands according to the marker compound. Camag scanner V was used for densitometric scanning. Further, the method was validated according to International Conference of Harmonization (ICH) guidelines. The Rƒ values of the three marker compounds were measured. Correlation coefficients were calculated from the standard graph of linearity. Accuracy, precision and recovery were all within the required limits. The developed HPTLC methods for bioactive marker compounds present in in-house and marketed formulations were found to be simple, accurate, precise and robust.