What Is Pharmacognosy?

Pharmacognosy is the study of medicines or drugs derived from natural sources, such as plants, animals, fungi, and microbes. According to the American Society of Pharmacognosy, it is “the study of the physical, chemical, biochemical and biological properties of drugs, drug substances or potential drugs or drug substances of natural origin as well as the search for new drugs from natural sources.”

It is long believed that the human body finds plant-based medications easier to accept because they exist in nature and are not artificial, man-made, or synthetic.

Both conventional medicine and alternative medicine use plants and organisms in a variety of ways to produce medications. The plant’s beneficial active ingredient may be found on any of the its physical structure, such as a root or a petal from a plant, or a cap from a mushroom.

The ingredient may be inactive in its natural form, so it may require certain chemicals to bring it into its active state. There are some instances that the ingredient is already active when it is just extracted from the plant.

Synthesis is applied by creating a compound that behaves exactly like the plant extract in order to produce an active ingredient.

Your prescription or over-the-counter drug is most likely to have an active ingredient derived from plants, molds, and other natural sources. Around 25% of prescription drugs in the USA are believed to have an active ingredient derived from nature. In developing countries, over 80% rely on traditional or alternative medicine that uses a variety of plants and herbs.

A short history of pharmacognosy

Historically, the term “pharmacognosy” refers to a branch of medicine or that dealt with “crude drugs.” Crude drugs are drugs that are obtained from nature and are used as such that they do not undergo any processing, for the exception of drying or size reduction.

Pharmacognosy is commonly regarded as the oldest form of pharmacy, with humans having been preparing drugs derived from plants and other natural resources. There’s a 5,000-year-old Sumerian clay from Nagpur that shows the evidence of medicine production. Another discovery is the twelve ancient medicinal recipes that have been found with natural ingredients such as mandrake and poppy. Several ancient texts also mention the production of drugs and medicines from plants.

During the 19th century, the extraction of alkaloids from poppies and other plants was responsible for the development of modern medicine. From that point on, other active ingredients have been derived from plants and other natural sources to develop medicinal products.

Since the 1930s, advances in biology and chemistry have enabled the development of pharmacognosy, enriching the study and methods of it. The development of the bioassay (an analytical measurement which determines the concentration or potency of a substance by its effect on living cells or living tissues) advanced the study and research of active ingredients of crude drugs. Such developments improved quality evaluation on these active ingredients.

Several methods, such as colorimetry, fluorescence analysis, spectrophotometry, were all applied to the gradual identification of crude drugs.

Here are some of the important events that contributed to the development of pharmacognosy:

  1. Isolation of penicillin (derived from the common mold) by Alexander Fleming in 1928. Large-scale production of penicillin began in 1941.
  2. Isolation of Vinca alkaloids (derived from Madagascar periwinkle), particularly vinblastine and vincristine, which are used to treat a number of types of cancer.
  3. Isolation of reserpine (derived from Indian snakeroot), validating its hypotensive and tranquilizing properties.
  4. Isolation of steroid hormones (such as progesterone) through partial synthesis from diosgenin (derived from many sources, such as crepe ginger plant) and other steroid saponins (derived from many sources such as soapwort, sea cucumber, soapberries, horse chestnut, etc.)

Pharmacognosy today

Pharmacognosy is still a relevant discipline for the discovery of potential medicinal products. Therefore, researchers are advised to be aware of the ethical issues regarding the use of natural products as medications.

For instance, consideration should be given to the conservation of various plants, animals, fungi, organisms, and other natural sources so that they will not be put at risk. There must also be an implementation of high standards of quality control to make sure that these natural sources are correctly identified. Any drugs derived from these sources must have sufficient degrees of purity so that they can be deemed safe to use.

It is highly suggested that periods of assessment should be put in place to identify the risks of long-term use of these natural medicines, as well as to determine their toxicity. Natural medicines are also often prescribed, recommended, or administered by individuals or groups that do not belong in medical or pharmaceutical organizations. Thus, their advice or endorsement of these medicines may not always be accurate or safe, and should not be always taken seriously.