THYMOL, MENTHOL AND CAMPHOR IN INDIA : CHOPRA & MUKHERJEE 361 ' sweetmeats, in pan supari' (betel leaf) mix- Articles tures, etc. The ajowan plant has, therefore, Original been grown to a greater or lesser extent all /over India. It is particularly abundant in Bengal, Central India (Indore) and Hyderabad THYMOL, MENTHOL AND CAMPHOrf (Deccan). 7,000 to 8,000 acres of land FROM INDIAN SOURCES Nearly are under cultivation each year in the Nizam's By R. N. CHOPRA, m.a., m.d. (Cantab.) Dominions alone and similar large areas are LIEUTENANT-COLONEL, I.M.S. also stated to be under cultivation in the and the United Provinces. i and Punjab Large quantities also find their way into India through B. m.b. MUKHERJEE, (Cal.) the inland routes from Afghanistan, Baluchistan Indigenous Drugs Enquiry, I. R. F. A., Series No. 35 and Persia. It can in fact be grown in any of the Indian Peninsula and the (From the Department of Pharmacology, School of part country Tropical Medicine, Calcutta) has possibilities of being a rich source of raw material for the of Indeed Thymol, menthol and camphor are well production thymol. this source has been the known in the materia medica of western already exploited by manufacturers as will be seen from the medicine as well as in that of the foreign indigenous of seeds from India between medicine in India. Thymol has been considered quantities exported 1911 and 1918 :? important on account of its powerful antiseptic, Value of germicidal and anthelmintic properties. One T otal the quantity seed of its chief uses in recent years has been in the in cwts. exported exported in ? treatment of hookworm disease. It is also sterling. used as a constituent of largely tooth-pastes 1911-12 15,515 4,583 as a skin and mouth-washes and disinfectant 1912-13 21,650 6,135 in dermatological practice. Menthol is exten- 1913-14 9,784 2,983 sively employed in liniments, spraying lotions 1914-15 7,368 2,736 1915-16 13,062 and in dental is one of the 4,871 practice. Camphor 1916-17 11,093 4,304 commonest remedies and is used in almost 1917-18 3,990 2,765 every household in India for a variety of pur- 1918-19 1,917 2,102 poses. The huge demand for these stearoptenes can, therefore, be easily understood. Large Besides this, Cuminum cyminum may also quantities of these drugs are imported from serve as a subsidiary source of thymol. foreign countries. It will, therefore, be inter- Cuminum cyminum is abundantly cultivated esting to examine the indigenous sources from all over India, particularly in the United Pro- which these drugs can be produced and the vinces and the Punjab as a field or garden crop possibilities of their manufacture in India on a and is exported in large quantities to Ceylon, commercial scale. the Straits Settlements and British East Africa. It contains 3 to 3.5 per cent, of cumin oil whose Thymol chief constituent is cumic or cuminic aldehyde in It is well known that thymol is contained which can be converted artificially into thymol. a number of essential oils occurring in many Irom Carum copticum.?It is common Thymol 1 ' plants distributed all over the world. The most knowledge that ajowan seeds have been dis- important source is the Spanish thyme, tilled in India by crude methods for centuries Thymus vulgaris or Thymus zygis, a small, and the impure thymol produced, known as ' evergreen shrub belonging to the Labiatse ajowan-ka-phul', has been used in the indi- family. It is indigenous in Spain, Portugal, genous medicine. The seeds distilled with water ' France and Italy and is also extensively culti- produce ajowan-ka-arak' which is well known vated in other parts of Europe and America, as a medicine to the people. It was, however, especially in Germany and in New York State. only as a result of the cutting off of foreign in Thymol also occurs in varying proportions supplies of thymol during the war, and the oils from Monarda punctata (American horse- stoppage of the export of seeds from India later, mint), Carum copticum (Indian ajowan), that definite attempts were made to manufac- Ocimum viride (the mosquito plant of West ture the article on a commercial scale. Africa), Ocimum gratissimum (Seychelles), Ajowan seeds from various sources in India Cunila mariana (North America), Mosla jjapo- have been examined for their oil contents. The which nica (Japan), etc. The chief source from seeds from different parts of the country yielded thymol can be produced in India is Carum varying proportions of oil ranging from 2.0 to as copticum. The seeds of this plant, known 3.5 per cent. Seeds obtained from the Kurnool- ' ajowan' seeds, have been used in the indi- Guntakal district of Madras Presidency genous medicine in the treatment of atonic appeared to be the beat variety obtainable in dyspepsia, diarrhoea, colic, flatulence, indigestion India. These seeds were thicker than the The aromatic seeds are exten- and cholera. ordinary seeds and were of a yellow colour and as a in to flavour sively used condiment curries, gave a high yield of oil, i.e., 3.5 per cont. The 362 THE INDIAN MEDICAL GAZETTE [July, 1932 seeds obtained from Northern India yielded of the seeds, however, are grown in India and only 2.07 per cent, of the oil, and the percentage as the export is completely stopped they will of thymol in most of the Indian oils is not have to be utilised or the cultivation will cease. more than 33 to 37 per cent. This is low as Some workers have shown that thymol manu- compared with the yield obtained from the facture in India should not be a failure if the Spanish thyme which is the chief competitor of by-products, e.g., spent seeds, omum water, ' ' the ajowan seeds. Besides this, Carum copti- thymene oil, etc., could be utilised. The spent cum grown in other parts of the world appears seeds contain 15 to 17 per cent, of protein and to give a larger yield of oil. A sample of seeds 25 to 32 per cent, of fat and can easily replace from the Seychelles gave on analysis 9 per ordinary oil-cakes in the fodder of cattle. The cent, and from Montserrat 3.1 per cent, of oil, omum water is already in extensive use as a containing 39 and 54 per cent, of thymol res- carminative, stomachic and stimulant. Thy- pectively. mene oil can be utilised in scenting cheap It would appear from this that the production soaps though it is never likely to be in great of thymol from raw materials at present avail- demand for such a purpose. Moreover better able in India would not be commercially a methods of cultivation are likely to improve successful proposition. Experiments conducted the yield of the oil. If this is done it is pos- in Hyderabad by the Department of Industries sible that with cheap labour and other factors and Commerce of the Nizam's Government present in this country, the production of thymol showed that the maximum yield of the oil was from distillation of ajowan seeds could be not more than 2 per cent, of the weight of the made economically successful. In addition to seeds and the yield of thymol crystals not more ajowan seeds, it will probably be worth while the of than 36.97 per cent, of the weight of the oil. considering possibility manufacture of With these results it does not appear to be. thymol from the ketone, piperitone, in this likely that the manufacture, on a commercial country. Eucalyptus trees grow very well in scale, of thymol will be successful. Manufac- many parts of India and eucalyptus oil is ture of the drug was actually taken up by the already being produced on a commercial scale. Gwalior and the Dhar States. The figures Large tracts of country are available for culti- for yield of the oil and thymol on a large scale vation of eucalyptus, and piperitone could be in Gwalior State are given in the following produced on a large scale. Its conversion into table :? thymol ought not to involve a large outlay of Quantity of Yield of oil Yield of crude capital. The whole question of manufacture fruit in lbs. in lbs. thymol in lbs. needs careful study by experts but, from the 26,076 742.5 321.2 data we have at our disposal, the position 22,227 652.5 269.1 appears to be hopeful. 32,380 943.7 370.5 A perusal of the table will show that the Menthol yield of crude thymol is not very high. The Menthol is obtained chiefly from Mentha manufacture in Dhar State appears not to have piperita or the marsh mint which grows ex- been a commercial success and has been dis- tensively in the British Isles and in the United continued. States of America. Though M. piperita does Commercial aspects of thymol production.? not grow in India, a number of other species Previous to 1914 thymol was chiefly produced of mentha grow quite well. Examples of these from natural sources. With the discovery of are Mentha viridis (spearmint), M. incana cheap methods of synthesis large quantities of (peppermint), M. sativa, M. aquatica and the drug are being synthetised. Several M. arvensis. All these varieties, excepting methods have been devised in Germany, M. arvensis, occur as garden plants and are America and England for manufacturing the sparingly distributed at present. M. arvensis article from crude phenols.