OPIUM- Alkaloids - Pharmacognosy and phytochemistry 2

Synonym: Raw opium.

Biological source: The latex is collected from unripe capsules upon incision of Papaver somniferum Linn. 

Family: Papaveraceae
Geographical source- India, Pakistan, Afghanistan, Turkey, Russia, China.

Cultivation, Collection 
 There are more than 50 different species exists in genus Papaver. Out of which six species are found in India like P. nudicaule, P. rhoeas, P. argemone, P. dubium P. somniferum
and P. orientale.
 It is an erect plant having 60-110 cm height approximately. It is branched having linear oblong or ovate oblong leaves, bluish white, violet or purplish flowers. Cultivation of opium is mainly done in certain regions like Madhya Pradesh, Punjab, Rajasthan and Uttar Pradesh under government supervision.

Chemical Constituent:
 Opium contains more than 30 alkaloids which are largely combined with the organic acid meconic acid. The drug also contains sugar salts, albuminous substances, colouring
matter and water. Six principle alkaloids are Morphine, Codeine, Thebaine, Noscapine (also known as narcotine), Narceine, Papaverine. The first group consist phenanthrene nucleus (morphine groups) whereas these of papaverine group have benzyl isoquinolene structure.
Morphine molecule have both phenolic and alcoholic hydroxyl group and when acetylated
forms diacetyl morphine or heroin. Codeine is an ether form of morphine (methyl morphine). Meconic acid is dibasic and easily detected either in Free State as meconate by the formation of a deep red colour on addition of ferric chloride. Less important opium alkaloids (protopine and hydrocotarine) are different structural type.

Chemical test:
• Opium is dissolved in water and filtered. To the filtrate add ferric chloride solution which gives deep reddish purple colour. This purple colour persists even on addition
of hydrochloric acid indicates the presence of meconic acid which ensures the detection of opium. This test is general for its detection.

• Morphine gives orange red colour when sprinkled on nitric acid whereas codeine does not gives this test.
• Morphine solution develops bluish green colour upon addition of potassium ferricyanide and ferric chloride.
• Papaverine solution develops lemon yellow colour with hydrochloric acid and potassium ferricyanide solution.

Uses:
It is used as hypnotic, sedative and analgesic but have addiction property so given in severe pain or if patient does not show response to other analgesics. It stimulates the
chemoreceptor zone in medulla which leads to nausea and vomiting. Codeine (mild analgesic which is potent to aspirin) relieves local irritation in the bronchial tract and as an antitussive. Papaverine has smooth muscle relaxant activity. Narcotine (or Noscapine) used
in the cough preparations due to its depressant action on cough reflex. Diacetyl morphine also known as Heroin has more narcotic analgesic effect than morphine.



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