Bottle Necks in Standardization of Traditional System of Medicines

INTRODUCTION

In many developed countries popular use of Complementary and Alternate Medicine (CAM) is fuelled by concern about the adverse effects of chemical drugs, questioning of the approaches and assumptions of allopathic medicine and greater public access to health information. At the same time, longer life expectancy has brought with it-increased risks of developing chronic, debilitating diseases such as heart disease, cancer, diabetes and mental disorders. For many patients, CAM appears to offer gentler means of managing such diseases than does allopathic medicine.

Regulators wrestle with questions of safety and efficacy of traditional herbal medicines, while many industry groups and consumers resist any health policy developments that could limit access to TM (Traditional medicine)/CAM therapies. Reports of powerful immunostimulant effects for some traditional medicines raise hope among HIV-infected individuals, but others worry that the use of such cures will mislead people living with HIV/AIDS and delay treatment with proven therapies (WHO, 1978).

In general, however, increased use of TM/CAM has not been accompanied by an increase in the quantity, quality and accessibility of clinical evidence to support TM/CAM claims.

Herbal products are the most commonly used complementary and alternative therapies. The medical and research community is constantly searching for new natural agents. Natural products are now a multibillion-dollar industry in the developed countries and these products are used by millions of people annually. Consumers now regularly ask most pharmacists about the benefits of natural products in treating their medical conditions. Consumers are bombarded with recommendations from friends, family, television advertisements and magazine articles giving advice about natural remedies. Herbal products are widely perceived as being safe by patients because they are considered natural. Most medications before being offered to consumers undergo rigorous evidence-based clinical testing; this is not necessarily true for herbs. Consumers regularly use these products without the knowledge of their healthcare professionals (Eisenberg et al., 1993, 1998). Therefore, it is important for developing better standardization techniques for traditional medicines. Plant species contain bewildering diversity of secondary metabolites. Accuracy in recording or observing the medicinal use of a plant, determining whether the ethno medical use can be demonstrated under scientific conditions in laboratory and/or chemical characterization of compounds and role of placebo effect are important issues that need to be verified in the development of drugs of plant (Kumar et al., 2004, 2005).

STANDARDIZATION OF HERBAL MEDICINE OF TRADITIONAL SYSTEM OF MEDICINE

Herbal medicine has its basis in the traditional system of medicine like Ayurveda, Unani, Kampo, Malay Chinese system of medicine etc. These traditional systems of medicine have been used for centuries and have certain standard procedures for its preparation and standardization. The cultural aspects of herbalism in different countries and societies play an important role to see the diversity of worldwide herbal use. In the traditional system of medicine like Ayurveda drugs are classified based on the Panca mahabhuta (Earth, water, fire, space and ether) is explained in association with its rasa (taste), guna (properties) and karma (action). The potency of the drug (veerya), target site (substratum), time of action (kala), stratagem (upaaya), targeted delivery with specific intention (abhipretha) are also expressed in the natural language which is associated with human cognitive processes, such as thinking and reasoning. Similarly all other traditional system of medicines has their own method of standardization for assuring quality most in human linguistic terms. This method of evaluation has to be taken into consideration in standardization of herbal medicine (Kumar et al., 2004, 2005; Venugopal, 2001).

WHO Guidelines for Quality Standardized Herbal Formulations (WHO, 1978):

The bioactive extract should be standardized on the basis of active principles or major compounds along with the chromatographic fingerprints (TLC, HPTLC, HPLC and GC). The standardization of crude drug materials includes the following steps:

Table 1:	Limits for microbial contamination
Afflatoxins should be completely removed or should not be present

In order to obtain quality oriented herbal products care should be taken right from the proper identification of plants; season and area of collection, extraction, isolation and verification process. Chemical and instrumental analyses are routinely used for analyzing synthetic drugs to confirm its authenticity. In the case of herbal drugs, however the scene is different especially for polyherbal formulation, as there are no chemical or analytical methods available. Therefore, biological-screening methods can be adopted for routine checkup of herbal drugs and formulations. In the case of herbal drugs, the quality of raw materials and products can be furnished by regular pharmacognostic identifications and phytochemical analysis. The herbal formulations in general can be standardized schematically as to formulate the medicament using raw materials collected from different localities and a comparative chemical efficacy of different batches of formulation are to be observed. The preparations with better clinical efficacy are to be selected. After all the routine physical, chemical and pharmacological parameters are to be checked for all the batches to select the final finished product and to validate the whole manufacturing process.

The stability parameters for the herbal formulations which includes physical parameters, chemical parameters and microbiological parameters.

Physical parameters include color, appearance, odor, clarity, viscosity, moisture content, pH, disintegration time, friability, hardness, flowability, flocculation, sedimentation, settling rate and ash values.

Chemical parameters includes limit tests, extractive values, chemical assays, etc.

Chromatographic analysis of herbals can be done using TLC, HPLC, HPTLC and GC, UV, Fluorimetry, GC-MS, etc.

Microbiological parameters include total viable content, total mold count, total enterobacterial and their count. Limiters can be utilized as a quantitative or semiquantitative tool to ascertain and control the amount of impurities like the reagents used during abstraction of various herbs, impurities coming directly from the manufacturing vessels, impurities from the solvents, etc.

Chemical decomposition of substances present in the formulation also produces several toxic or impure compounds during storage in undesirable conditions. Contaminants may come directly from the atmosphere also. This include mainly dust, sulfur dioxide, H₂S, CO₂, arsenic, moisture, etc.

The guidelines set by WHO (Shrikumar et al., 2004) can be summarized as follows:

Modern herbal ayurvedic monographs: In the modern herbal ayurvedic monographs the standardization parameters are discussed in a comprehensive way. According to the modern ayurvedic monograph the quality control protocols include the following:

Title, synonyms, publications related to that plant, constituents present, analytical methods.

Descriptive evaluation: Description of the drug, phytomorphological, microscopical, organoleptic evaluations, foreign matter, foreign minerals, etc.

Physicochemical parameters: Identity: Physical and chemical identity, chromatographic finger prints, ash values, extractive values, moisture content.

Strength: Ethanol and water extractive values, volatile oil and alkaloidal assays, quantitative estimation protocols, etc.

Biological activity evaluation: Bitterness values, astringency, swelling factor, form index, hemolytic index, etc.

Toxicological evaluation: Pesticide residues, heavy metals, microbial contamination like total viable aerobic count, pathogens like E. coli, Salmonella, P. aeruginosa, S. aureus, Enterobacteria, etc.

Aflatoxins: The presence of aflatoxins can be determined by chromatographic methods using standard aflatoxins B₁, B₂, G₁, G₂ mixtures. Aflatoxin is a product of the microbial strain Aspergillus flavus.

Radioactive contaminants
Bottle backs of the existing methods are: