JOURNAL OF THE SOCIETY tribasic acid, isochlorophyllin (V). Further, since commercial oil- soluble medicinal chlorophylis have usually lost part, often the greater part, of their magnesium, water- soluble chlorophylIs l•repared from such materials will also contain a corresponding amount of "mag- nesium-free chlorophyllins" corre- sponding to the mono- and tri-basic acids mentioned above. If, on the other hand, the water- soluble chlorophylis are prepared from copper-treated, oil-soluble chlorophyll, the green component of which is copper phaeophytin, the chlorophyllins obtained are sodium or potassium copper chlorophyllins. They contain copper in place of magnesium. These compounds are intensely blue-green in colour, and are very fast to light--much more m than the oil-soluble, copper- treated chlorophylIs from which they are made. The water-soluble chloro- phylis made from non-copper- treated, oil~so}uble chlorophyll have a dull green to brown colour, the green tint diminishing with the mag- nesium content. Such material is of relatively small value as a colouring agent. Whether or not the water-soluble chlorophylis contain magnesium, are magnesium-free, or contain copper, their solubility characteristics are similar. They dismlve quite readily in water, giving faintly alkaline solutions. If such a solution is acidi- fied, the water-insoluble acidic chlorophyllins are thrown' down as a flocculent precipitate, the super- natant liquid being left practically OF COSMETIC CHEMISTS colourless. Hence the chlorophyllins cannot be used to colour acidic aqueous solutions, but only those ,which are neutral or moderately alk- aline. They will not readily dissolve in strongly alkaline solutions, and tend to be precipitated unchanged from aqueous solution by the addi- tion of too much alkali this is due to a "salting out" effect. However, despite these limitations, the chloro- phyllins, especially those containing copper, are very useful for colouring aqueous solutions. They are also particularly suitable for colouring alcoholic solutions some grades are only soluble in solutions containing up to about 60 per cent v/v. alco- hol, but others will dissolve com- pletely in 90 per cent v/v. alcohol. Such alcoholic solutions, when made strongly acid or alkaline, tend to throw down a precipitate contain- ing some or all of their original green colour. Apart from alcohol, the chlorophyllins are insoluble in most organic solvents, including the hydrocarbons and acetone. The chlorophyllins are insoluble in fixed and essential oils. Those grades which are soluble in strong alcohol can, however, be used to colour alcoholic solutions of essential oils such as perfume formulations. This is worth remembering, especially since the oil-soluble grades, though soluble in essential .oils, are only poorly soluble in alcohol. The water-soluble chlorophyllins are available in various forms and strengths. Liquid or semi-liquid forms usually contain water, in which case they must also contain 190

CHLOROPHYLL a suitable proportion of glycerol or other preservative to prevent fer- mentation or mould growth. Granu- lar or powdered forms are available. The granular forms of the medicinal grades are particularly suitable for the preparation of tablets. The selection of a particular grade of chlorophyll, eitner oil or water- soluble, for any particular purpose should only be made after practical tests have demonstrated its suita- bili,•. Ho.wever, reputable brands of chlorophyll are generally offered in definite grades, of standardized strengths. Thus, when a particular make and grade has been selected, the user can be assured of reproduc- ible results with it. The second part of the paper was devoted to a discussion of the newer medicinal uses of chlorophyll which have developed in recent years. Such developmeats have been con- cerned mainly with the water-soluble grades. The speaker deplored the fact that, in many papers published on this subject, there had been a failure adequately to define the nature of the material used. Biirgi, in 1916, began to publish papers describing his experiments on the administration of phaeophytin and other chlorophyll derivatives to animals and humans, claiming that it stimulated the production of haemoglobin and improved the appetite. Later he devised a prepar- ation containing chlorophyll and a small amount of iron. This was claimed to be very successful in the treatment of secondary anaemias and to have a general tonic effect. It forms the basis of a proprietary preparation that has been available for a number of years. Other similar products have also been used quite widely and apparently with some Success. The further work of Biirgi, and also. of Patek, Gruskin and Bowers was briefly summarised, and refer- ence was made to the fact that the Council of Pharmacy and Chemistry of the A.M.A. had conducted a con- trolled trial of the action of chloro- phyll ointments and solutions in promoting the healing of wounds, and had concluded that such pre- parations do in fact possess a sig- nificant beneficial effect. The much more far-reaching claims of Westcott were next exam- ined. This worker, in investigating the value of water-soluble chloro- phyll in the treatment of anaemias, had observext a very d•stinct 'de- crease in urine odour. In particular, the characteristic odour caused by the ingestion of vitamin B• was largely suppressed. He proceeded to conduct in vitro tests, using the Fair and Wells metallic osmoscope to, measure the odours, and showed that the water-soluble chlorophyllin had a significant effect in reducing the odours of benzyl mercaptan, thioglycollic acid and trimethyl- amine. Following up this work, he studied the effects of oral admini- stration of the material on body odours in general. He found that a dose of 100 mg. of the material, taken early in the day, in most cases caused complete disappearance or 191