**1.1 Spectrophotometry and chemical fingerprints of herbal medicines**

In general one or two markers or pharmacologically active compounds of herbal components or herbal blends were used to evaluate the quality and authenticity of herbal medicines in the identification of a single herb or preparation of herbal medicine and to evaluate the quantitative composition of a herbal product. However, this type of determination does not give a complete picture of the herbal products because multiple ingredients are usually responsible for its therapeutic effects. These therapeutic effects may work synergistically and change their activity on being separated into their active parts. So various analytical techniques can be applied for this type of registration and the complete herbal product can be considered as the "active compound" (Liang et al., 2004).

testing and specifications of identity, purity and contents of the principal active ingredients or markers for each plant drug, in order to guarantee the conservation of the species and the specifications of microbiological purity. Currently the quality requisites of the different national pharmacopoeias vary between countries, however the International Federation of Pharmaceutical Manufacturer Associations, have taken a first step towards the global implementation of organized criteria (International Federation of Pharmaceutical Manufacturer Associations [IFPMA], 1997). The World Health Organization has conducted a review of the legal status of traditional medicine and complementary or "alternative" therapies in 123 countries (World Health Organization [WHO], 2001). Moreover, some countries and organizations have developed, or are developing, their own monographs, for example, the Commission E of the German Ministry of Health, WHO and European Scientific Cooperative on Phytotherapy, China, Brazil and Argentina, among others. These monographs recognise the quality standards applicable to drugs and herbal remedies in the pharmaceutical market. (Blumenthal, 1998; European Scientific Cooperative on

In Argentina there is great interest in controlling the Quality, Security and Efficacy of herbal medicines. In order to achieve this ambitious objective the following steps must be taken: a-Registration of the products, b- Verification of good practices of production and quality control, of the crude drug and its products, and c- Pharmacovigilance. ANMAT (National Administration of Drug, Food and Medical Technology) is the organism responsible for authorizing all activities related to medicines through its technical organism, the INAME (National Institute of Drug). The products based on herbal medicine and aromatics are considered as Phytotherapeutic Drugs in Resolution Nº 144/98 and the Supplementary Provisions (**Provision 2671/99; Provision 2672/99; Provision 2673/99)** that are now in effect. Provision 1788/2000 contains a list of 109 herbal medicines that can not be authorised for the production of herbal medicine on account of the contradictions or toxic effects reported

It is very important that plant material is of the highest quality as it is used as a medicine. The aforementioned decrees aim to guarantee the quality of the raw material, the intermediate and finished products and a series of tests have been established among which, as a minimum requisite, are botanical identity, purity (physical-organoleptic and microbiological - for health) and their activity or composition (methodological analysis), taking into account the Good Practices of Agricultural Production and the Good Practices of

In general one or two markers or pharmacologically active compounds of herbal components or herbal blends were used to evaluate the quality and authenticity of herbal medicines in the identification of a single herb or preparation of herbal medicine and to evaluate the quantitative composition of a herbal product. However, this type of determination does not give a complete picture of the herbal products because multiple ingredients are usually responsible for its therapeutic effects. These therapeutic effects may work synergistically and change their activity on being separated into their active parts. So various analytical techniques can be applied for this type of registration and the complete

**1.1 Spectrophotometry and chemical fingerprints of herbal medicines** 

herbal product can be considered as the "active compound" (Liang et al., 2004).

Phytotherapy [ESCOP], 2003; Keller, 1991; WHO, 1991, 1999, 2002).

in their traditional use.

Manufacturing (Rodriguez, 2010a).

The concept of phytoequivalence was developed in Germany to ensure the consistency of herbal products (Tyler, 1999). According to this concept, a chemical profile, such as a spectrophotometric fingerprint for a herbal product should be constructed and compared with the profile of a clinically tested reference product. Therefore, a spectrophotometric fingerprint of a herbal medicine is a spectrophotometric pattern of an extract of some chemical components that are pharmalogically active and/or with chemical characteristics. It is suggested that with the help of spectrophotometric fingerprints obtained, the authentication and identification of herbal medicines would be appropriate, even when the amount and/or concentration of some typical chemical ingredients are not exactly the same for different samples of these herbal medicines. In this way, we are broadly considering multiple ingredients in the extracts of herbal medicines rather than one or two marker ingredients for evaluating the quality of the herbal products.

In general various analytical techniques can be used to obtain fingerprints of herbal medicines of which chromatography is most often used on account of its great efficiency in separating the different components of an extract. For the above mentioned reasons these chromatographic techniques have a high cost, especially if they are to be used for routine quality control. A simple alternative technique such as UV/Visible spectrophotometry, coupled to chemometric methods was carried out by Lonni et al. (2005) for taxonomic purposes. Authors were able to separate populations of three species of *Baccharis* according to their UV / Visible spectra. Here, we propose to apply the same methodology as part of quality control of herbal medicines.

Figure 1 shows the spectrophotometric profiles of ethanol extracts of the aerial parts of *Baccharis gaudichaudiana* DC. obtained from five areas in Misiones province, Argentina (MI1, MI2, MI3, MI4, MI5) (Rodriguez, 2010b). Here, of course, some differences can be observed in the profiles; however phytoequivalence for *B. gaudichaudiana* can be seen.

Fig. 1. Absorption UV/Visible spectra of *Baccharis gaudichaudiana* populations (Bg). MI, Misiones. Numbers indicate when there is more than one population of the same species.

Quality Control of Herbal Medicines with Spectrophotometry and Chemometric Techniques

– Application to *Baccharis* L. Species Belonging to Sect – Caulopterae DC. (Asteraceae) 403

Fig. 2. Absorption UV/Visible spectra. **A**, *Baccharis articulata* (Ba); **B**, *Baccharis trimera* (Bt) populations. BA, Buenos Aires; COR, Corrientes; ER, Entre Ríos; SF, Santa Fe. Numbers

**2. An example of differentiation of** *Baccharis* **L. species belonging to sect – Caulopterae DC. (Asteraceae) using UV/Visible spectrophotometry data and** 

*Baccharis* L. is an exclusive American genus comprising approximately 500 species. Its distribution area covers the whole of South America and continues northwards up to the south of USA including the Atlantic coast up to Massachusetts, although its presence is greater in the intertropical and subtropical zones (Cuatrecasas, 1967; Müller, 2006). Several

indicate when there is more than one population of the same species

**multivariate analysis** 
