Pharmacognosy is the study of physical, biological, chemical and biochemical properties of drugs of natural origin, obtained from organisms such as most plants, microbes, and animals. Up to date, many essential drugs including morphine, atropine, galanthamine, etc. have originated from natural sources which continue to be useful model molecules in drug discovery. The word ‘Pharmacognosy’ is derived from the Greek words "Pharmakon" (a drug) and "gnosis" (knowledge). Pharmacognosy broadly covers the knowledge of the history, distribution, cultivation, collection, selection, preparation, commerce, identification, evaluation, preservation, and use of drugs.
Importance of Pharmacognosy
In other words, pharmacognosy is described as the systematic science of morphological, chemical, and biological properties along with history, cultivation, collection, extraction, isolation, bioassaying, quality control, and preparation of crude drugs of natural origin. Pharmacognosy has played a pivotal role in the development of new drugs and therapies. Pharmacognosy, which literally means studying medications of natural sources, has been a part of healthcare since mankind first began to treat illnesses. There is a need for drug discovery due to the prevalence of many diseases without suitable medical products.
Plant drugs that are newly discovered are being converted into medicines as purified phytochemicals. This concept of pharmacognosy is essentially the reason for the advanced medicines evolution, and crude drugs are useful in the preparation of therapeutic metabolites. Pharmacognosy becomes an important link between pharmaceuticals and basic science. Traditionally, pharmacognosy was regarded as one of the key aspects of drug developing processes. Pharmacognosy concept is mostly used by all pharmaceutical companies for screening, characterizing and producing newly advanced method to treat diseases in human beings. The concept of pharmacognosy involves the botanical knowledge for classifying and naming the plant species, understanding its genetic pattern as well as cultivation, and also chemical knowledge for isolating and quantitatively assessing the bioactive compounds in the plant sources.
Natural products play a significant role as starting material for drug discovery. Plants are a valuable source of ingredients for traditional medicines for years. Examples include artemisinin from the Qinghaosu tree or Artemisia annua is recognized as an ancient Chinese drug for malaria.
Microorganisms have great potential as natural sources of drugs. They are known as a prolific source of natural products, most of which are medicinally essential products. The rapid development of technologies and tools has made it possible to isolate new and diverse natural products.
Despite the success of the emergence of natural products approach in the drug discovery process, it has faced few challenges in recent years due to some factors. These factors include:-
• Lack of results
• High cost of collection of the natural product sample
• Long resupply time for active extracts
• Difficulty in isolating active compound from the extract
• Problems with large scale supply if a drug emerges from natural sources
• Slow growth and sparsely distribution of the species
• Diversion of resources to combinatorial chemical approaches to drug discovery
Despite all these challenges, natural products play a vital role in the drug discovery process. The importance of natural products in therapy is clear from the analysis of the number of drugs containing these substances and drugs derived from natural formulas.
Pharmacognosy is a significant contributor to the knowledge and understanding of drugs and therapies. It is evident that drug discovery from medicinal plants continues to provide new and important leads against various pharmacological targets. Current research in drug discovery from medicinal plants comprises a multifaceted approach that includes botanical, computational, phytochemical, biological, and molecular techniques. New approaches are necessary to facilitate antimicrobial drug development during a time of rapidly rising antibiotic resistance. Plants remain a unique source of bioactive compounds, and ethnobotanical research tools can accelerate future research and narrow down the search to the most likely source candidates. Natural products from microbes can be expected to play an important role in the ongoing transition from empirical screening to rational drug design.
Over the years, scientific research has expanded our knowledge of the chemical effects and composition of the active constituents, which determine the medicinal properties of the plants. The last decade has seen greater use of botanical products among members of the general public through self-selection than ever before. This phenomenon has been mirrored by increasing attention to herbal remedies (phytomedicines) as a form of alternative therapy by the health professions inclusive of pharmacy and medicine. The advancement of modern medicine comes up with life-saving therapies and the importance of natural products has been widely studied because undoubtedly it will offer a lot in the ages to come.