BETEL NUT. The name betel is applied to two different plants, which in the East are very closely associated in the purposes to which they are applied. The betel nut is the fruit of the Areca or betel palm, Areca Catechu, and the betel leaf is the produce of the betel vine or pan, Chavica Betel, a plant allied to that which yields black pepper. The Areca palm is a native of the Malay Peninsula and Islands and is extensively cultivated over a wide area in the East, including southern India, Ceylon, Siam, the Malay Archipelago and the Philippine Islands. It is a graceful tree with a straight, slender, unbranched stem reaching 40 or 50 ft. in height and about 11 ft. in circumference, and bearing a crown of 6–9 very large spreading pinnate fronds. The fruit is about the size of a small hen’s egg, and within its fibrous rind is the seed or so-called nut, the albumen of which is very hard and has a prettily mettled grey and brown appearance. The chief purpose for which betel nuts are cultivated and collected is for use as a masticatory,—their use in this form being so widespread among Oriental nations that it is estimated that one-tenth of the whole human family indulge in betel chewing. For this use the fruits are annually gathered between the months of August and November, before they are quite ripe, and deprived of their husks. They are prepared by boiling in water, cutting up into slices, and drying in the sun, by which treatment the slices assume a dark brown or black colour. When chewed a small piece is wrapped up in a leaf of the betel vine or pan, with a pellet of shell lime or chunam; and in some cases a little cardamom, turmeric or other aromatic is added. The mastication causes a copious flow of saliva of a brick-red colour, which dyes the mouth, lips and gums. The habit blackens the teeth, but it is asserted by those addicted to it that it strengthens the gums, sweetens the breath and stimulates the digestive organs. Among the Orientals betel is offered on ceremonial visits in the same manner as wine is produced on similar occasions by Europeans. Betel nuts are further used as a source of catechu, which is procured by boiling the nuts in water. The water of the first boiling becomes red and thick, and when this is inspissated after the removal of the nuts it forms a catechu of high astringency and dark colour called in Bombay “Kossa.” The nuts are again boiled, and the inspissated juice of the second decoction yields a weaker catechu of a brown or reddish colour. Betel nuts have been used by turners for ornamental purposes, and for coat buttons on account of the beauty of their structure. At one time they were supposed to be useful as a vermifuge. The nuts of other species of Areca are used by the poorer classes in the East as substitutes for the genuine betel nut.
The alkaloid arecaidine, C7H11NO2, occurs in areca or betel nuts, together with three other alkaloids: arecoline, C8H13NO2, guvacine, C6H9NO2, and arecaine, C7H11NO2. Arecaidine forms white crystals easily soluble in water, and difficultly soluble in alcohol. Chemically it is methyl-tetrahydro-nicotinic acid. Dehydration results in the formation of a “betaïne,” which is a tetrahydro-trigonelline (see Betaïne). Arecoline is an oil, and the physiological action of the betel nut is alone due to this substance. Chemically it is the methyl ester of arecaidine. Guvacine, named from “guvaca,” an Indian designation of the betel palm, forms white crystals. It is a secondary base, but its constitution is uncertain. Arecaine is n-methyl-guvacine.