Biologically active substances (BAS) are compounds that, due to their physicochemical properties, have a certain activity and have a positive effect on a certain function of the body, sometimes not just stimulating or changing it, but also completely replacing it.

There are no absolutely indifferent substances. All substances to a certain extent affect the functions of the body, helping to achieve a certain effect.

The largest amount of biologically active compounds is found in plant foods. Such substances are called phytocompounds. They have an impact on metabolic processes and contribute to the neutralization of foreign substances in the body. In addition, they can bind free radicals.

According to their chemical nature, biologically active compounds are subdivided into terpenes, phenols, thiols and lignans.

Terpenes

Terpenes are phyto compounds that act as antioxidants. This group also includes carotenoids. To date, more than 600 carotenoids are known,

Phenols and polyphenols

Among phenols and their compounds, the most studied are flavonoids. Today, about 5000 representatives of flavonoids have been identified, studied and described.

Flavanones are a specific flavonoid found in citrus fruits. They are also found in, but only in certain types of them and in very small quantities.

Flavanones include hesperitin, anthocyanins, and proanthocyanidins. These substances are found in apples, black and red currants, black tea, red, chocolate and all types of citrus fruits. All of these active substances prevent the development of atherosclerotic diseases, contribute to the prevention of cardiovascular diseases. There is an assumption according to which the active compounds of these groups also have anti-inflammatory and antiviral effects.

Thiols

Cruciferous vegetables such as broccoli and various types of cabbage contain sulfur-containing biologically active substances. They include several subgroups - indoles, dithiolthions and isothiocyanates.
It has been proven that the consumption of these active substances inhibits the likelihood of cancer of the lung, stomach, colon and rectum. This phenomenon is closely related to the action of thiol compounds.
Thiol-related active substances are found in onions and garlic.

Lignans

Another subgroup of active phyto-compounds are lignans. They are found in flax seeds, wheat bran, rye flour, and oatmeal, barley.
The consumption of foods containing lignans significantly reduces the risk of developing cardiovascular and oncological diseases.

Federal Agency for Education

State educational institution

higher professional education "Perm State Technical University" Department of Chemistry and Biotechnology

Chemistry of biologically active compounds

Lecture notes for full-time students

in the specialty 070100 "Biotechnology"

Publisher

Perm State Technical University

Compiled by: Cand. Biol. Nauk L.V. Anikina

Reviewer

Cand. chem. Sciences, Assoc. I.A.Tolmacheva

(Perm State University)

Chemistry of biologically active substances/ comp. L.V. Anikina - Perm: Perm Publishing House. state tech. University, 2009 .-- 109 p.

A summary of lectures on the program of the course "Chemistry of biologically active substances" is presented.

It is intended for full-time students in the direction 550800 "Chemical technology and biotechnology", specialty 070100 "Biotechnology".

© GOU VPO

"Perm State

Technical University ", 2009

Introduction ………………………………………………………………………… ..4

Lecture 1. Chemical components of living …………………………………… .7

Lecture 2. Carbohydrates …………………………………………………………… .12

Lecture 3. Lipids …………………………………………………………… ..20

Lecture 4. Amino acids ………………………………………………… ..… 35

Lecture 5. Proteins …………………………………………………………….… .43

Lecture 6. Properties of proteins ………………………………………………… ... 57

Lecture 7. Simple and complex proteins ………………………………………… ... 61

Lecture 8. Nucleic acids and nucleoproteins ………………………… .72

Lecture 9. Enzymes ……………………………………………………….… .85

Lecture 10. Classification of enzymes …………………………………… ... 94

Introduction

When training specialists in biotechnology, the most important basic disciplines are biochemistry, organic chemistry and chemistry of biologically active substances. These disciplines constitute the fundamental basis of biotechnology, with the development of which they associate the solution of such major social problems of our time as the provision of energy, feed and food resources, the protection of the environment and human health.

According to the requirements of the State Standard of Higher Professional Education for the mandatory minimum content of basic educational programs in the direction 550800 "Chemical technology and biotechnology", specialty 070100 "Biotechnology", the discipline "Chemistry of biologically active substances" includes the following didactic units: structure and spatial organization of proteins, nucleic acids acids, carbohydrates, lipids, low molecular weight bioregulators and antibiotics; the concept of enzymes, antibodies, structural proteins; enzymatic catalysis.

The purpose of teaching the discipline "Chemistry of biologically active substances" is to form students' ideas about the structure and foundations of the functioning of biologically active substances, about enzymatic catalysis.

Lectures on the discipline "Chemistry of Biologically Active Substances" are based on the students' knowledge of the courses "General Chemistry", "Inorganic Chemistry", "Physical Chemistry", "Analytical Chemistry" and "Chemistry of Coordination Compounds". The provisions of this discipline are used for further study of the courses "Biochemistry", "Microbiology", "Biotechnology".

The proposed lecture notes cover the following topics read in the course "Chemistry of Biologically Active Substances":

Carbohydrates, classification, chemical structure and biological role, chemical reactions inherent in carbohydrates. Monosaccharides, disaccharides, polysaccharides.

Lipids. Classification by chemical structure, biological functions of lipids and their derivatives - vitamins, hormones, bioregulators.

Amino acids, general formula, classification and biological role. Physicochemical properties of amino acids. Proteinogenic amino acids, amino acids as precursors of biologically active molecules - coenzymes, bile acids, neurotransmitters, hormones, histohormones, alkaloids, and some antibiotics.

Proteins, elemental composition and functions of proteins. Primary protein structure. Characterization of the peptide bond. Secondary protein structure: α-helix and β-folding. Supersecondary protein structure, domain principle of protein evolution. The tertiary structure of the protein and the bonds that stabilize it. The concept of fibrillar and globular proteins. Quaternary protein structure.

Physicochemical and biological properties of proteins. Denaturation. Chaperones.

Simple proteins: histones, protamines, prolamins, gluteins, albumins, globulins, scleroproteins, toxins.

Complex proteins: chromoproteins, metalloproteins, lipoproteins, glycoproteins, proteoglycans, nucleoproteins.

Nucleic acids, biological role in the cell. Nitrogen bases, nucleosides, nucleotides, DNA and RNA polynucleotides. Types of RNA. Spatial structure of DNA, levels of DNA compaction in chromatin.

Enzymes as biological catalysts, their difference from non-protein catalysts. Simple and complex enzymes. The active center of the enzyme. The mechanism of action of enzymes, a decrease in activation energy, the formation of an enzyme-substrate complex, the theory of bond deformation, acid-base and covalent catalysis. Enzyme isoforms. Polyenzyme systems.

Regulation of enzyme activity at the cellular level: limited proteolysis, molecular aggregation, chemical modification, allosteric inhibition. Inhibition types: reversible and irreversible, competitive and non-competitive. Enzyme activators and inhibitors.

Enzyme nomenclature. International classification of enzymes.

Oxidoreductases: NAD-dependent dehydrogenases, flavin-dependent dehydrogenases, quinones, cytochrome system, oxidases.

Transferases: phosphotransferases, acyltransferases and coenzyme-A, aminotransferases using pyridoxal phosphate, C 1 -transferases containing active forms of folic acid and cyanocobalamin, glycosyltransferase as coenzymes.

Hydrolases: esterases, phosphatases, glycosidases, peptidases, amidases.

Lyases: decarboxylases using thiamine pyrophosphate, aldolase, hydratase, deaminase, synthase as coenzyme.

Isomerases: transfer of hydrogen, phosphate and acyl groups, movement of double bonds, stereoisomerase.

Ligases: conjugation of synthesis with the breakdown of ATP, carboxylase and the role of carboxybiotin, acyl-coenzyme A-synthetase.

At the end of the lecture notes, there is a list of literature that must be used for the successful mastering of the course "Chemistry of biologically active substances".

Substances (abbreviated as BAS) are special chemicals that, at low concentrations, have high activity towards certain groups of organisms (humans, plants, animals, fungi) or certain groups of cells. BAS are used in medicine and as a prophylaxis of diseases, as well as to maintain full-fledged life.

Biologically active substances are:

1. Alkaloids - nitrogen-containing nature. Typically of plant origin. They have basic properties. They are insoluble in water, form various salts with acids. They have good physiological activity. In large doses - these are the strongest poisons, in small doses - medicines (medicines "Atropine", "Papaverine", "Ephedrine").

2. Vitamins are a special group of organic compounds that are vital for animals and humans for good metabolism and full life. Many of the vitamins take part in the formation of the necessary enzymes, inhibit or accelerate the activity of certain enzyme systems. Also vitamins are used as food (they are part of them). Some vitamins enter the body with food, others are formed by microbes in the intestines, and still others appear as a result of synthesis from fat-like substances under the influence of ultraviolet radiation. Lack of vitamins can lead to various metabolic disorders. A disease that arose as a result of a small intake of vitamins in the body is called vitamin deficiency. Lack - and excessive amount - hypervitaminosis.

3. Glycosides are organic compounds. They have a wide variety of effects. Glycoside molecules are composed of two important parts: non-sugar (aglycone or genin) and sugar (glycone). In medicine, it is used to treat diseases of the heart and blood vessels, as an antimicrobial and expectorant. Also, glycosides relieve mental and physical fatigue, disinfect the urinary tract, calm the central nervous system, improve digestion and increase appetite.

4. Glycolalkaloids - biologically active substances related to glycosides. The following drugs can be obtained from them: "Cortisone", "Hydrocortisone" and others.

5. (another name - tannins) are able to precipitate proteins, mucus, adhesives, alkaloids. For this reason, they are incompatible with these substances in medicines. With proteins, they form albuminates (anti-inflammatory agent).

6. Fatty oils are fatty acids or trihydric alcohol. Some fatty acids are involved in the elimination of cholesterol from the body.

7. Coumarins are biologically active substances based on isocoumarin or coumarin. This group also includes pyranocoumarins and furocoumarins. Some coumarins have an antispasmodic effect, others have a capillary-strengthening activity. There are also coumarins antihelminthic, diuretic, curariform, antimicrobial, analgesic and other effects.

8. Trace elements, like vitamins, are also added to biologically active food supplements. They are part of vitamins, hormones, pigments, enzymes, form chemical compounds with proteins, accumulate in tissues and organs, in the endocrine glands. The following microelements are important for humans: boron, nickel, zinc, cobalt, molybdenum, lead, fluorine, selenium, copper, manganese.

There are other biologically active substances: (there are volatile and non-volatile), pectin substances, pigments (another name is dyes), steroids, carotenoids, flavonoids, phytoncides, ecdysones, essential oils.

All vital activity of the organism is based on three pillars - self-regulation, self-renewal and self-reproduction. In the process of interacting with a changing environment, the body enters into complex relationships with it and constantly adapts to changing conditions. This is self-regulation, an important role in the provision of which belongs to biologically active substances.

Basic biological concepts

Self-regulation in biology is understood as the body's ability to maintain dynamic homeostasis.

Homeostasis is the relative constancy of the composition and functions of the body at all levels of organization - cellular, organ, systemic, and organismic. And it is at the latter that the maintenance of homeostasis is provided by biologically active substances of the regulatory systems. And in the human body, the following systems are engaged in this - the nervous, endocrine and immune systems.

Biologically active substances secreted by the body are substances that can, in small doses, change the rate of metabolic processes, regulate metabolism, synchronize the work of all body systems, and also affect individuals of the opposite sex.

Multilevel regulation - a variety of agents of influence

Absolutely all compounds and elements that are found in the human body can be considered biologically active substances. And although they all have specific activity, performing or influencing catalytic (vitamins and enzymes), energy (carbohydrates and lipids), plastic (proteins, carbohydrates and lipids), regulatory (hormones and peptides) functions of the body. All of them are divided into exogenous and endogenous. Exogenous biologically active substances enter the body from the outside and in various ways, and all elements and substances that are part of the body are considered endogenous. Let us stop our attention on some substances important for the vital activity of our body, and give a brief description of them.

The main ones are hormones

Biologically active substances of humoral regulation of the body are hormones that are synthesized by the glands of internal and mixed secretion. Their main properties are as follows:

1. They act at a distance from the place of formation.
2. Each hormone is strictly specific.
3. They are quickly synthesized and quickly inactivated.
4. The effect is achieved at very low doses.
5. They play the role of an intermediate link in nervous regulation.

The secretion of biologically active substances (hormones) is provided by the human endocrine system, which includes endocrine glands (pituitary gland, pineal gland, thyroid, parathyroid, thymus, adrenal) and mixed secretion (pancreas and gonads). Each gland secretes its own hormones, which have all of the listed properties, work according to the principles of interaction, hierarchy, feedback, relationship with the external environment. All of them become biologically active substances of human blood, because only in this way are they delivered to the agents of interaction.

Mechanism of action

Biologically active substances of the glands are included in the biochemistry of life processes and affect specific cells or organs (targets). They can be of a protein nature (somatotropin, insulin, glucagon), steroid (sex and adrenal hormones), be derivatives of amino acids (thyroxine, triiodothyronine, norepinephrine, adrenaline). Biologically active substances of the endocrine and mixed secretion glands provide control over the stages of individual embryonic and postembryonic development. Their lack or excess leads to disorders of varying severity. For example, a lack of biologically active substance of the endocrine gland of the pituitary gland (growth hormone) leads to the development of dwarfism, and its excess in childhood leads to gigantism.

Vitamins

The existence of these low molecular weight organic biologically active substances was discovered by the Russian physician M.I. Lunin (1854-1937). These are substances that do not perform plastic functions and are not synthesized (or synthesized in a very limited amount) in the body. That is why the main source for obtaining them is food. Like hormones, vitamins act in small doses and ensure the course of metabolic processes.

In terms of their chemical composition and effects on the body, vitamins are very diverse. In our body, only vitamins of group B and K are synthesized by the intestinal bacterial microflora, and vitamin D is synthesized by skin cells under the influence of ultraviolet radiation. All the rest we get with food.

Depending on the supply of the body with these substances, the following pathological conditions are distinguished: avitaminosis (complete absence of any vitamin), hypovitaminosis (partial deficiency) and hypervitaminosis (excess of vitamin, more often - A, D, C).

Trace elements

Our body contains 81 elements of the periodic table out of 92. All of them are important, but we need some in microscopic doses. These trace elements (Fe, I, Cu, Cr, Mo, Zn, Co, V, Se, Mn, As, F, Si, Li, B and Br) have long remained a mystery to scientists. Today, their role (as amplifiers of the power of the enzyme system, catalysts of metabolic processes and building elements of biologically active substances in the body) is beyond doubt. A deficiency of a trace element in the body leads to the formation of defective enzymes and disruption of their functions. For example, zinc deficiency leads to disruptions in the transport of carbon dioxide and to disruption of the entire vascular system, the development of hypertension.

And there are many examples, but in general, a deficiency of one or several microelements leads to delays in development and growth, disorders of hematopoiesis and the functioning of the immune system, and an imbalance in the regulatory functions of the body. And even premature aging.

Organic and active

Among the many organic compounds that play an important role in our body, we highlight the following:

1. Amino acids, of which twelve out of twenty-one are synthesized in the body.
2. Carbohydrates. Especially glucose, without which the brain cannot function properly.
3. Organic acids. Antioxidants - ascorbic and amber, antiseptic benzoic, heart enhancer - oleic.
4. Fatty acid. Well-known Omega-3 and 5.
5. Phytoncides, which are found in plant foods and have the ability to destroy bacteria, microorganisms and fungi.
6. Flavonoids (phenolic compounds) and alkaloids (nitrogen-containing substances) of natural origin.

Enzymes and nucleic acids

Among the biologically active substances of the blood, two more groups of organic compounds should be distinguished - these are enzyme complexes and adenosine triphosphoric nucleic acids (ATP).

ATP is the body's universal energy currency. All metabolic processes in the cells of our body occur with the participation of these molecules. In addition, active transport of substances through cell membranes is impossible without this energy component.

Enzymes (as biological catalysts for all life processes) are also biologically active and necessary. Suffice it to say that erythrocyte hemoglobin cannot do without specific enzyme complexes and adenosine triphosphoric nucleic acid, both in fixing oxygen and in its release.

Magic pheromones

One of the most mysterious biologically active formations are aphrodisiacs, the main purpose of which is to establish communication and sexual attraction. In humans, these substances are secreted in the area of ​​the nose and lip folds, the chest, in the anal and genital areas, and the armpits. They work in minimal quantities and are not consciously realized at the same time. The reason for this is that they enter the vomeronasal organ (located in the nasal cavity), which has a direct neural connection with the deep structures of the brain (hypothalamus and thalamus). In addition to attracting a partner, recent studies prove that it is these volatile formations that are responsible for fertility, instincts for caring for offspring, maturity and strength of marriage, aggressiveness or submissiveness. The male pheromone androsterone and female copulin are rapidly degraded in the air and only work with close contact. That is why you should not particularly trust cosmetic manufacturers who actively exploit the topic of aphrodisiacs in their products.

A few words about dietary supplements

Today you cannot find a person who has not heard of dietary supplements (BAA). In fact, these are complexes of biologically active substances of various compositions, which are not drugs. Dietary supplements can be a pharmaceutical product - dietary supplements, vitamin complexes. Or food products additionally enriched with active ingredients that are not contained in this product.

The world market for dietary supplements is huge today, but Russians are not lagging behind either. Some polls have shown that every fourth resident of Russia takes this product. At the same time, 60% of consumers use it as a supplement to food, 16% - as a source of vitamins and microelements, and 5% are sure that biologically active additives are medicines. In addition, there have been registered cases when, under the guise of dietary supplements such as sports nutrition and weight loss products, supplements were sold in which psychotropic substances and narcotic drugs were found.

You can be a supporter or opponent of the reception of this product. World opinion is replete with various data on this issue. In any case, a healthy lifestyle and a varied, balanced diet will not harm your body, will eliminate doubts about taking certain nutritional supplements.

Introduction

Any living organism is an open physicochemical system that can actively exist only under conditions of a sufficiently intense flow of chemicals necessary for the development and maintenance of structure and function. For heterotrophic organisms (animals, fungi, bacteria, protozoa, chlorophyll-free plants), chemical compounds supply all or most of the energy necessary for their life. In addition to supplying living organisms with building material and energy, they perform various functions of information carriers for one organism, provide intra- and interspecific communication.

Thus, the biological activity of a chemical compound should be understood as its ability to change the functional capabilities of the body ( invitro or invivo) or a community of organisms. This broad definition of biological activity means that almost any chemical compound or composition of compounds has some kind of biological activity.

Even chemically very inert substances can have a noticeable biological effect when administered appropriately into the body.

Thus, the probability of finding a biologically active compound among all chemical compounds is close to unity, however, finding a chemical compound with a given type of biological activity is a rather difficult task.

Biologically active substances- chemical substances necessary to maintain the vital activity of living organisms, which have high physiological activity at low concentrations in relation to certain groups of living organisms or their cells.

Per unit of biological activity chemical substance take a minimum amount of this substance capable of suppressing the development or retarding the growth of a certain number of cells, tissues of a standard strain (biotests) in a unit of nutrient medium.

Biological activity is a relative concept. One and the same substance can have different biological activity in relation to the same type of living organism, tissue or cell, depending on the pH value, temperature, and the presence of other biologically active substances. Needless to say, if we are talking about different biological species, then the effect of a substance can be the same, expressed in varying degrees, directly opposite, or have a noticeable effect on one organism and be inert for another.

Each type of biologically active substance has its own methods for determining the biological activity. So, for enzymes, the method for determining the activity is to register the rate of consumption of the substrate (S) or the rate of formation of reaction products (P).

Each vitamin has its own method for determining the activity (the amount of vitamin in a test sample (for example, tablets) in IU units).

Often in medical and pharmacological practice such a concept as LD 50 is used - i.e. the concentration of the substance upon the introduction of which half of the test animals die. This is a measure of the toxicity of biologically active substances.

Classification

The simplest classification - General - divides all BAS into two classes:

• endogenous
• exogenous

Endogenous substances include