Chapters :
  • Chemistry in everyday life – 01



Chemistry in everyday life – 01

  • Antibiotics are used as drugs to treat infections because of their low toxicity for humans and animals. Initially antibiotics were classified as chemical substances produced by microorganisms (Bacteria, Fungi and Molds) that inhibit the growth or even destroy microorganisms.
  • The development of synthetic methods has helped in synthesizing some of the compounds that were originally discovered as products of microorganisms. Also, some purely synthetic compounds have antibacterial activity, and therefore, definition of antibiotic has been modified. An antibiotic now refers to a substance produced wholly or partly by chemical synthesis, which in low concentration inhibits The Growth or Destroys Microorganisms by intervening in their metabolic processes.
  • The search for chemicals that would adversely affect invading bacteria but not the host began in the nineteenth century. PAUL EHRLICH, A German Bacteriologist, conceived this idea. He investigated arsenic based structures in order to produce less toxic substances for the treatment of syphilis. He developed the medicine, ARSPHENAMINE, KNOWN AS SALVARSAN.
  • PAUL EHRLICH GOT NOBEL PRIZE FOR MEDICINE IN 1908 for this discovery. It was the FIRST EFFECTIVE TREATMENT FOR SYPHILIS. Although salvarsan is toxic to human beings, its effect on the bacteria, spirochete, which causes syphilis is much greater than on human beings.
  • The range of bacteria or other microorganisms that are affected by a certain antibiotic is expressed as its spectrum of action. Antibiotics which kill or inhibit a wide range of Gram-Positive and Gram-Negative Bacteria are said to be broad spectrum antibiotics. Those effective mainly against Gram-positive or Gram-negative bacteria are narrow spectrum antibiotics.
  • If effective against a single organism or disease, they are referred to as limited spectrum antibiotics. PENICILLIN G has a narrow spectrum. AMPICILLIN AND AMOXYCILLIN are synthetic modifications of PENICILLINS. These have broad spectrum. It is absolutely essential to test the patients for sensitivity (allergy) to penicillin before it is administered.


  • ANTISEPTICS AND DISINFECTANTS are also the chemicals which either kill or prevent the growth of microorganisms.
  • Antiseptics are applied to the living tissues such as wounds, cuts, ulcers and diseased skin surfaces. These are not ingested like antibiotics.
  • Commonly used antiseptic, Dettol Is A Mixture of Chloroxylenol And Terpineol Bithionol (The Compound Is Also Called Bithionol) is added to soaps to impart antiseptic properties. IODINE is a powerful antiseptic. Its 2−3 per cent solution in alcohol water mixture is known as tincture of iodine. It is applied on wounds. LODOFORM is also used as an antiseptic for wounds. Boric acid in dilute aqueous solution is weak antiseptic for eyes.
  • DISINFECTANTS are applied to inanimate objects such as floors, drainage system, instruments, etc. Same substances can act as an antiseptic as well as disinfectant by varying the concentration. For example, 0.2per cent solution of phenol is an antiseptic while its one percent solution is disinfectant. CHLORINE in the concentration of 0.2 to 0.4ppm in aqueous solution and Sulphur dioxide in very low concentrations, are disinfectants.
    • BIRTH CONTROL PILLS essentially contain a mixture of synthetic estrogen and progesterone derivatives. Both of these compounds are hormones. It is known that progesterone suppresses ovulation. Synthetic progesterone derivatives are more potent than progesterone.
  • NORETHINDRONE is an example of synthetic progesterone derivative most widely used as ANTIFERTILITY DRUG. The estrogen derivative which is used in combination with progesterone derivative is ETHYNYLESTRADIOL (NOVESTROL).
  • NATURAL SWEETENERS, e.g., sucrose add to calorie intake and therefore many people prefer to use artificial sweeteners. Ortho-sulphobenzimide, also CALLED SACCHARIN, is the First Popular Artificial Sweetening Agent. It has been used as a sweetening agent ever since it was discovered in 1879. It is about 550 times as sweet as cane sugar. It is excreted from the body in urine unchanged. It appears to be entirely inert and harmless when taken. Its use is of great value to diabetic persons and people who need to control intake of calories.
  • ASPARTAME is the most successful and widely used artificial sweetener. It is roughly 100 times as Sweet as Cane Sugar. It is methyl ester of Dipeptide Formed from Aspartic Acid and Phenylalanine. Use of aspartame is limited to cold foods and soft drinks because it is unstable at cooking temperature.
  • ALITAME is high potency sweetener, although it is more stable than aspartame, the control of sweetness of food is difficult while using it.
SUCROLOSE IS TRICHLORO derivative of sucrose. Its appearance and taste are like sugar. It is stable at cooking temperature. It does not provide calories
error: Content is protected !!
Scroll to Top