Evaluation of extraction methods for pharmacologically active compounds from anticonvulsant traditional Chinese medicines: Gou Teng, Tian Ma, Jiang Can using DART-TOF-MS

• NCJ Number: 304469
• Journal: Analytical Methods Volume: 13 Issue: 7 Dated: 2021
• Author(s): K. N. Karin; et al
• Date Published: 2021
• Grant Number(s): 2016-DN-BX-0150
• Agencies: NIJ-Sponsored

Annotation

Since laboratories must be able to efficiently analyze cases in which Chinese herbal medicines (CHMs) are suspected, five extractions were evaluated for their ability to extract pharmacologically active compounds from herbal matrices: water, ethanol, microwave-assisted (MAE), ethanol[thin space (1/6-em)]:[thin space (1/6-em)]chloroform, and acid-wash.

Abstract

Chinese herbal medicines (CHMs) are classified as dietary supplements. Interactions with western medications, the presence of contaminants or adulterants, or a mis-labeled or mis-used CHM may lead to toxicological emergencies that can be undetected in death investigations. Anticonvulsive and other pharmacologically active compounds in Gou Teng, Tian Ma, and Jiang Can purchased from Beijing, China and New York were compared in the powder and the extracts using Direct Analysis in Real Time-Mass Spectrometry (DART-MS). Approximately 0.25 g of macerated herb was used per extraction. The water and ethanol extractions were simple liquid extractions. For the MAE, powdered herb was soaked in 65% ethanol, microwaved, and concentrated. The ethanol[thin space (1/6-em)]:[thin space (1/6-em)]chloroform extraction involved soaking in 1[thin space (1/6-em)]:[thin space (1/6-em)]1 ethanol[thin space (1/6-em)]:[thin space (1/6-em)]chloroform, sonication, and concentration. In the acid-wash extraction, powdered herb was soaked in acetic acid, followed by addition of sodium hydroxide, hexane extraction, and reconstitution in ethyl acetate. The powdered herbs and extracts were analyzed using a Jeol JMS T100LC AccuTOF DART-MS in positive and negative mode. Of the evaluated methods, no single extraction worked for all active compounds from the three CHMs. The MAE extract contained the most pharmacologically active compounds, while the acid-wash contained the least for the three products. Gou Teng purchased from different sources did exhibit a difference in pharmacologically active compounds, potentially from different species. (Publisher Abstract)