Plant Physiology - Musienko M.M. 2001

Plant Physiology and Biotechnology: Achievements and Development Prospects
Biologically Active Substances of Medicinal Plants and Pharmacognosy

Green plants, through Photosynthesis and subsequent transformations, are capable of synthesizing virtually all Organic compounds. All other organisms, including humans, are unable to independently produce the organic substances necessary for life. The therapeutic effect of plants is rooted in The Unity of METABOLISM within living Cells; despite A number of significant differences between plants, animals, and humans, their core Metabolic pathways are remarkably similar. Metabolic and energy processes can be disrupted by a deficiency in the diet of certain substances that The Human Body cannot synthesize on its own. To treat deficiency diseases, specific plant products containing the missing substance must be introduced into the human diet.

For instance, the suppression of pathogenic microflora—Bacteria, Fungi, Viruses, and Protozoa—is achieved through substances with antibiotic properties. Potent phytoncides found in garlic, onions, horseradish, and many aromatic herbs regulate the population and COMPOSITION OF THE intestinal microflora. The Essential Oils of lavender, mint, thyme, and oregano are lethal to microbes that enter the Lungs and mucous membranes.

The mobilization of the human body's defenses is achieved through The Use of adaptogens (such as ginseng and eleuthero). Certain plant compounds, particularly Alkaloids, actively influence the central and autonomic nervous systems.

The medicinal properties of plants depend on the presence of various substances with diverse chemical structures and therapeutic effects. The most important among them include Proteins and Amino Acids, Nucleic Acids, alkaloids, CARBOHYDRATES, dietary fiber, Glycosides, saponins, essential oils, Waxes, phenols, Flavonoids, resins, Tannins, Vitamins, and others (A.M. Hrodzynskyi, 1992).

Legumes—such as peas, beans, and soybeans—and cereals—such as wheat, rye, barley, and oats—are rich in PROTEINS AND AMINO acids. Proteins also function as Enzymes. To enrich our own enzyme systems with plant-derived ones, plants must be consumed fresh and in their green state. Although proteins and Amino acids are not yet used directly in phytotherapy, they are of exceptional importance for the vital activity of the Organism.

Quite complex plant compounds known as alkaloids, numbering over 5,000, are found exclusively in plants. Most of them are non-volatile organic compounds that are physiologically and pharmacologically very active, sometimes poisonous or acting as narcotics. Depending on their chemical nature, the pharmacological significance of alkaloids varies greatly. For example, morphine acts as a potent analgesic against severe pain, atropine and papaverine exhibit spasmolytic effects, quinine acts specifically against the malaria parasite, and caffeine and theobromine stimulate respiratory centers. Many alkaloids exert a profound effect on The Nervous system, which is why some of them—such as morphine and cocaine—are among the most powerful narcotics. Alkaloid-bearing plants include white hellebore (protoveratrines A and B), black henbane, jimsonweed, and belladonna (hyoscyamine, atropine, scopolamine), opium poppy (morphine group), celandine (chelidonine), cinchona tree (quinine), and tobacco and wild tobacco (nicotine).

Among plant glycosides, cardiac glycosides are widely used; they are found in the leaves of foxglove, oleander, lily of the valley, pheasant's eye (adonis), and others. Plants of the Brassicaceae family are characterized by the presence of sulfur in their glycosides (sinigrin, sinalbin). Rosaceous plants contain amygdalin, which breaks down with the release of hydrocyanic acid. In the green parts of flax, the glycoside linamarin also contains hydrocyanic acid. Buttercups contain anemonin and protoanemonin. The leaves of birch and ivy, as well as licorice ROOT, contain saponins—glycosides of various natures that irritate mucous membranes because they act as surface-active agents and enhance intestinal peristalsis.

Many metabolic processes require fats and oils that are not synthesized in the human body—such as Unsaturated Fatty acids (linoleic, linolenic, arachidonic)—which are found exclusively in plant fats and so-called fish oil. In addition to pharmaceutical Applications, fats and oils are used in industry and cosmetics. The most common are sunflower, rapeseed, olive, and peanut oils, among others.

Essential oils are produced exclusively in plants and possess quite strong physiological and pharmacological properties. Each of them—whether peppermint, lavender, or rose oil—is a mixture of several Terpenes and their derivatives. Overall, essential oils are important remedies for clearing mucus and urine from the body, exhibiting spasmolytic and choleretic effects, and demonstrating a distinct static action against bacteria. The most common essential oil-bearing plants include dill, valerian, lavender, lovage, lemon balm, mint, parsley, coriander, oregano, juniper, wormwood, rose, lemon, and orange.

Many herbal preparations and mixtures utilize various compounds grouped under the name bitters. They enhance the secretion of glands—salivary, pancreatic, gastric, and the Gallbladder.

Most frequently, bitters are found in plants of the Asteraceae (Compositae), Gentianaceae, and Lamiaceae families.

A widely distributed group in the plant kingdom is phenols. The simplest phenol is phenol proper, or carbolic acid, an effective disinfectant. Under the action of enzymes, phenols polymerize into insoluble molecules of tannins, Lignin, Melanins, and humus. Phenolic Compounds play a crucial role in wound healing, Cell Division, and the protection of Tissues against radiation, mutagens, and strong oxidizing agents.

Derivatives of phenolic compounds, known as flavonoids, exhibit diverse phytotherapeutic effects. The most common among them are rutin, quercetin, hesperidin, hyperoside, kaempferol, and apigenin. 362

Their sources include arnica flowers, buckwheat, European elder, chamomile, linden blossom, parsley root, field horsetail, and others. The most significant pharmaceutical action of flavonoids is The regulation of capillary condition; they reduce capillary permeability in atherosclerosis, tone Heart Muscles, dilate coronary vessels, and reduce Blood clotting.

Tannins (pyrogallols, pyrocatechols), resins, and balsams also possess medicinal properties and are used as raw Materials in the pharmaceutical industry.

Finally, green plants are capable of synthesizing virtually all vitamins. Moreover, vitamin activity is usually exhibited not by a single substance, but by a group of related compounds that are converted within the body into the required active form.

The use of herbal remedies in modern medicine not only remains quite stable (herbal preparations account for up to 40% of all medicines, and up to 80% in certain drug groups) but even shows a tendency to grow. Furthermore, medicinal plants are used in significant quantities in the perfumery, cosmetic, food, and liquor industries, and even in technical applications.

Due to the fact that pharmacologically active substances are products of biological synthesis within the plant organism, and their accumulation depends on ontogenesis and The Influence of various environmental factors, it becomes entirely clear that modern pharmacognosy must be closely linked with the physiology and biochemistry of medicinal plants.