Medicinal Plants

Since time immemorial man has known about the medicinal properties of plants and widely -sed them for all practical purposes. At present the attention to medicinal plants as natural sources of drugs has greatly increased. Ten thousand plant detectives try to find new plants rossessing medicinal properties on five continents and all seas.

Different parts of a plant may be used for medicinal purposes: roots and rhizomes, fruits ;r.d seeds, flowers and inflorescences, stems and leaves. All these parts are collected in a certain reriod of time.

It is well-known that the proper time of harvesting or collecting plants and herbs is during ■'-at period when active constituents of the plant are highest in their number and quality. Roots ir.d rhizomes are collected in autumn after the vegetative processes have finished. Bark is :: ilected in spring before these processes begin. Leaves and flowering tops are collected when : r. otosynthesis is most active which is usually about the time of flowering and before the maturing ::" the fruit and seed. Flowers are collected in the time of pollination. Fruit may be collected r.ther before or after the ripening period. Seeds may be collected when fully matured.

Proper storage and preservation are an important factor in maintaining a high degree of :-ality of the drug. Thus, too much moisture increases the weight of the drug, decreases the amount of active constituents. Air and light affect drugs, which are strongly colored, produci". changes in constituents of drags.

All parts of the plant differ as to the shape, taste, color, odor, and pharmacological activi:;. Thus, the usual shapes for fruits and seeds are globular, elliptical, ovoid, conical, etc. The odor c: a drug of plant origin may be either distinct or indistinct, depending upon the amount of volatile constituents the drug possesses. It is described as aromatic, balsamic, spicy, camphorous, eu When it is difficult to compare the odor with other substances, it is described as characteristic

According to taste substances may be classified into four groups:

1. those possessing a true taste, such as acid, sweet, alkaline, bitter;

2. those possessing no taste and thus being tasteless;

3. those possessing a characteristic odor which gives name to the so-called "taste". The;, may be grouped broadly into those which are agreeable or pleasant (aromatic, balsamic, spic\ and disagreeable or unpleasant (alliaceous, camphorous, etc.);

4. those giving certain sensation to the tongue. Such substances may be classified as mucilaginous, oily, astringent, pungent, acrid, nauseous.

The taste, color and odor of drugs are officially standardized with the help of drug description, are of the lightness and strength of the color. Reserpine is described as "a white or pale to slightly yellowish, odorless, crystalline powder". Olive oil is described as "a pale yellow liquid which sometimes has a greenish tint"; rhizome and roots of valerian as "light brown or yellow brown, odor strong and peculiar, taste - spicy, sweetish-bitterish".

Pharmacological activity of certain drugs is established using different tests and methods, such as chemical analysis for the determination of presence of inorganic elements, a chemical analysis for the determination of the official activity, chromatographic study to separate and analyse constituents and inert materials occurring in drugs.

Exercise 9. Read the sentences. Add attributes to the underlined words.

1. Parts of a plant such as roots, rhizomes, fruits, bark, seeds, flowers, leaves, etc. may be used for medicinal purposes. 2. The time of harvesting or collecting plants and herbs is during the period when active constituents of a plant are highest in their number and quality. 3. It is necessary to store and preserve medicinal plants properly in order to maintain the degree of quality of the drug. 4. The presence of moisture decreases the amount of their constituents. 5. It is not difficult to compare odors. 6. Reserpine is described as a powder. 7. Olive oil sometimes has a tint. 8. The activity of certain drugs is established using different tests and methods.

Exercise 10. Complete the sentences.

1. Flowers are collected ... .2. Bark is collected in the spring before ... .3. Roots and rhizomes are collected in autumn after ... .4. Man has known about the medicinal properties of plants since ... .5. Ten thousand plant detectives try to find new plants which ... .6. Fruits may be collected either before or after... .7. Seeds may be collected when .... 8. Odor is described as characteristic when ....

Exercise 11. Fill in the blanks with the words given below.

1. The odor of a rose is described as .... 2. The usual ... for fruits or seeds is globular. 3. The odor of a drug of plant origin depends upon the amount of... constituents. 4. Olive oil is described as a pale yellow ... which sometimes has a greenish tint. 5. The psychological ... of opium plant was known to the ancient population of many south-eastern countries. 6. Garlic is used in the treatment of many ... in a pure state or as a compound or mixture. 7. Due to modern laboratories it can be shown how garlic ... microbes.

(liquid, effect, agreeable, shape, affect, disease, volatile)

Exercise 12. Read the sentences, use the verbs in the correct form (indefinite or perfect).

1. In Bulgaria and the Caucasus there is a great number of people who (to live) to the age of 100 and are still active. 2. Investigations of scientists on the activity of garlic (to make) garlic oil very popular since that time. 3. Experiments on the medicinal properties of plants (to show/ that some of their constituents are very active against microbes. 4. Last season our botanical station (to pay) special attention to the proper storage of herbs. 5. Second-year roots usually і to contain) high properties of alkaloids. 6. By 1906 Russian botanist Tswett (to publish) a description of the technique for separating pigments of green leaves.

Exercise 13. Discuss the text answering the questions.

1. What facts prove that the attention to medicinal properties of plants has greatly increased at present? 2. How can you define fruits and seeds? Roots and rhizomes? 3. What period do we call "proper time of harvesting"? 4. Are different pans of plants and herbs gathered at different periods? Give some examples. 5. Why is it necessary to gather medicinal plants at proper time? 6. What factors affect the amount and quality of plant constituents? 7. What odor do we call

"characteristic"? 9. Into what groups are medicinal herbs divided according to taste? 10. How

s pharmacological activity of certain drugs established?

Exercise 14. Tell your pen friend about medicinal plants according to the plan.

1. Medicinal plants as a source of drags.

2. The attention to medicinal plants has increased in the present period.

3. The use of different parts of plants for medicinal purposes.

4. Proper storage and preservation of medicinal plants.

5. Taste, color and odor and their role in the description of plants.

LESSON THIRTY-NINE

Control Test

. To have a heart of means to be very 2. is made of dead and weakened

•..nd. germs.

A. silver A. A drug

B. stone B. A chemical

C. bronze C. A medicine

D. gold D. A vaccine

E. iron E. A serum

3. is a written order for medicine.

A. A label

B. A sick list

C. A direction

D. A prescription

E. An instruction

4. like doors, will open with ease.

A. Wounds

B. Hospitals

C. Heart

D. Hearts

E. Windows

5. You use when you are nervous.

A. a laxative

B. a sedative

C. an antiseptic

D. an adhesive

E. an antibiotic

6. A nurse must her feelings.

A.speak

B. control

C. show

D. understand

E. demonstrate

7. A person who has may have a running

nose.

A. a fever

B.a headache

C. a flu

D. a stomachache

E. a toothache

8. Another name for sickness is .

A.ache

B. pain

C. disease

D. virus

E. happiness

9. when you feel bad.

A. Get an injection

B. Write in your chart

C. Take your temperature

D. Drink tea

E. Have a snack

10. A nurse observes changes in patient's

A. feelings

B. condition

C. look

D. state

E. all of the above

11. A doctor patients.

A. prescribes

B. examines

C. works

D. observes

E. chooses

12. One can take in case of pain.

A. a sedative

B. an antiseptic

C. a laxative

D. a syringe

E. an analgetic

13.A doctor usually gives a patient before

surgery.

A. an anesthesia

B. a sedative

C. a laxative

D. an antibiotic

E. a tablet

14. disease is a disease you get from

another person.

A. A child

B. An infectious

C. A heart

D. A cardiovascular

E. A lung

15. A nurse doctor's instructions.

A. gives

B. sees

C. carries out

D. begins

E. does

16. is a wonderful organ that works every

moment of your life.

A. Pulse

B. The heart

C. Blood

D. Blood pressure

E. The head

.". When a nurse takes your pulse, she

note the strength of beating.

A. can

B. is to

C. must

D. will

E. may