Analytical methods herbal preparations

Providing rapid multiresidue analytical profiling is a first step toward effective quality control of herbal preparations. For example, Luo et al. [5] developed a method for the simultaneous analysis of protoberberine alkaloids, indolequinoline alkaloids, and quinolone alkaloids (Figure 13.1) extracted from the traditional Chinese medicinal... 

The identification test methods should be specific for the herbal material, herbal preparation or finished herbal product and ideally should be capable of discriminating between the required herbal material and potential substitutes or adulterants that are likely to occur. The identification methods used for groups a and b should be capable of detecting the said active ingredients and at least the main ingredients should be stated on the label. For group c, the analytical procedure should be based on characteristic constituents, if any. 

The development and execution of quality control methods for herbal materials, herbal preparations and the finished herbal products should be in line with subsection 15.1 (Specifications). Tests and quality requirements that are characteristic of the given analyte should be selected. 

As a consequence of the toxicity related to the presence of aristolochic acid in plant preparations, several health institutions, such as the US Food and Drug Administration, Therapeutic Goods Administration have recently published safety information to prevent further cases of intoxication (information available at web address http //www.cfsan.fda. gov/ dms/ds-bot.html) [471], So detecting aristolochic acids in plant species that could be used in herbal remedies, and also in herbal preparations of uncertain composition, has attracted great priority in recent years to help prevent future adverse reactions. Aristolochic acids present in medicinal plants or herbs are analyzed by soxhlet extraction followed by TLC in the Chinese pharmacopoeia [412]. Another report used multiple ultrasonic extraction followed by HPLC analysis [472]. Ong s laboratory reported a method using a home made pressurized liquid extraction (PLE) system in dynamic mode to extract aristolochic acid in medicinal plants, followed by gradient elution HPLC [473]. Several scientific communities described various analytical methods for... 

The characteristics of multiconstituent, multitarget effect mechanisms have restricted the revelation of the active material basis of Chinese herbal medicine, which makes the quality control of herbal medicine a problem. Therefore, study of analytical methods of the chemical constituents in Chinese herbal medicine is not only a significant challenge that pharmaceutical analysts face but also a key link in the investigation of the material basis of Chinese herbal medicine. Generally, there are three types of chemical analysis of Chinese herbal medicine (1) the analysis of chemical constituents in Chinese medicine materials (2) the analysis of chemical constituents in a prescription and (3) the analysis of the original drug and its metabolites in body fluids (such as blood serum, tissue, urine, etc.) or in vitro bacteria/cell metabolism. The analysis of various trace-level constituents and metabolites in Chinese herbal medicines and their pharmaceutical preparations is critical to the research of such complex mixture systems. 

Most of the TLC systems are standard systems and have been optimized when necessary. In spite of other available analytic techniques, such as gas chromatography and high performance liquid chromatography, TLC still remains a most useful, quick, effective, and low-cost method for the separation and identification of complex mixtures of herbal drug preparations and plant constituents. 

PAs have a large variety of related structures, and include both tertiary (free base) compounds and their corresponding N-oxides (PANOs), which behave differently in many analytical systems. The analytical requirements are for methods for detecting PAs in wild and cultivated plants, in plants and plant preparations used for dietary supplements and herbal medicines, hay, silage and compound animal feeds, foods including honey, milk, and teas. 

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