Standardization Strategies for Herbal Drugs-An Overview
Neeli Rose Ekka*. Kamta Prasad Namdeo and Pradeep Kumar Samal
SLT Institute of Pharmaceutical Sciences, Guru Ghasidas University ,Bilaspur (CG.)
*Corresponding Author E-mail: nreekkarose@ yahoo.co.in
ABSTRACT:
Eighty of world population is dependent on herbal drugs and to enter into the global market it is vital to maintain its quality. The quality of herbal drugs is the sum of all factors which contribute directly or indirectly to the safety, effectiveness and acceptability of the product .Standardization of drugs means confirmation of its identity and determination of its quality and purity. Initially the crude drugs were identified by comparison only with the standard description available. At present due to advancement in the chemical knowledge of crude drugs various methods like botanical, chemical, spectroscopic and biological methods are used for estimating active constituents present in the crude drugs in addition to its physical constants.
KEY WORDS: Standardization, quality, purity, herbal products.
INTRODUCTION:
A system to ensure that every packet of medicine that is being sold has the correct substances in the correct amount and will induce its therapeutic effect this is known as standardization.
It is very important that a system of standardization is established for every plant medicine in the market because the scope for variation in different batches of medicine is enormous. Plant material may vary in its phytochemical content and therefore in its therapeutic effect according to different places of collection, with different times in a year for collection, with collection at the same time and places but in different years and with different environmental factors surrounding the cultivation of a particular medicinal plant. Adding to this variability is the fact that in herbal medicine several plants may be used together in the same preparation. This means that there should be a quality control test for the entire preparation to ensure quality of the product.
World Health Organization (WHO) encourages, recommends and promotes traditional /herbal remedies in national health care programmes because these drugs are easily available at low cost, safe and people have faith in them. The WHO assembly in number of resolutions has emphasized the need to ensure quality control of medicinal plant products by using modern techniques and applying suitable standards.1-2
PHARMACOPOEIAL STANDARDS3-7 :
The authenticity, quality and purity of herbal drugs are established by reference given in pharmacopoeia. The pharmacopoeia prescribes (numerical value) like structural, analytical, physical standards for the drugs. The important standards mentioned in pharmacopoeia are shown in figure 1.
A critical examination and identification of crude drugs is required in manufacturing of herbal formulation because of great diversity and variability in their chemical characters. To overcome this problem all the pharmacopoeias have laid down certain standards.
Specific tests for certain plant materials are given below.
Volatile oil content Hemolytic activity Foaming index Bitter value Tannin content. Fat content Acid valueSaponification value Iodine value Assay forAluminium/ Arsenic /Borate/Calcium. Camphor/ Chloride/Copper/ Gold/Iron. Lead/Magnesium/ Mercury/Phosphate. Potassium/Silica/ Silver/Sodium.Sulpher/Sulphate/Tin.
PHYTOCHEMICAL ASSAY8-19 :
Most of the drugs have definite specific chemical constituents to which their biological or pharmacological activity is attributed. Qualitative and quantitative characterization of the active ingredient should be assayed using biomarkers. Defining of the biomarker has to be very specific and a lot of insight has to go into it before declaring any distinct molecule. Additionally the mixture should be analyzed to develop finger print profile. A general protocol followed for chemical assay for herbal drugs is shown in figure 2.
Figure 1. Standardization parameters for plant drugs
Pharmacopoeial standards
Isolation of compounds Column chromatography Partition chromatography Thin layer chromatography Gas liquid chromatography High performance liquid chromatography High performance thin layer chromatography.
Figure 2. Phyto chemical evaluation of herbal drugs
PROCESS CONTROL OF HERBAL DRUGS:
Drugs are manufactured from different raw materials by using different methods or process. Some impurities are incorporated into the material during the manufacturing process. Multiple-step procedure which produces intermediate compounds. In- process control provides information on general characters, identification test and other applicable tests such as inorganic and heavy metal impurity, microbial limit, and pesticide reside besides, safety, assay and stability. In addition to the foregoing portions of the initial final and in process samples are used for collecting average run samples for the quality control laboratory to perform final batch analysis and release. Process control is shown in figure 3.
CONTROL OF FINISHED PRODUCT:
Specification for finished product should be defined. Final testing of finished product is made in the quality control laboratories. These tests are designed to determine compliance with specifications. Thus the testing of the finished product for compliance with predetermined standard prior to release of the product for packaging and subsequent distribution is a critical factor for quality assurance. This testing along with in process testing, assures that each unit contains the amount of drug claimed on the label, that all of the drug in each unit is available for complete absorption, that the drug is stable in the formulation in its specific final container closure system for its expected shelf life and that dosage units. themselves contain no toxic foreign substances. The label of herbal medicine should have all the particulars required by national regulations.
The label and package insert should have at least the following information.
Name of the product. List of active ingredient together with Latin botanical name and their quantities. Dosage form. Indication. Dosage for adults, children and elderly. Mode of administration. Duration of use. Major adverse effects, if any. Over dosage information. Contra-indication, warning precautions and major drug interactions. Use during pregnancy and lactation. Expiry date. Batch /lot number. Name, address of the manufacturer together with authorization number.
Figure 3. Flow chart of process control of herbal drugs
CONCLUSION:
The pharmacopoeial standards in Ayurvedic Pharmacopoeia of India are not adequate enough to ensure the quality of plant materials since the materials received in the manufacturing premises are not in a condition that effective microscopic examination can be done. Therefore chemical, methods, instrumental methods and then layer chromatographic analysis would determine the proper quality of plant material
Thus we can ensure consistent quality of herbal product through following.
Use of approved quality of all raw materials.
Use of all approved packing material.
Standardized and well validated methods of processing and manufacture.
Complete finished product quality control testing.
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Received on 01.09.2008 Modified on 10.11.2008
Accepted on 12.12.2008 © RJPT All right reserved
Research J. Pharm. and Tech. 1(4): Oct.-Dec. 2008; Page 310-312