SYNTHETIC VITAMINS

New Zealand Herald, Volume LXIX, Issue 21296, 24 September 1932, Page 7 (Supplement)

SYNTHETIC VITAMINS

ACHIEVEMENT BY CHEMIST The discovery of the chemical formula of Vitamin C by a young Norwegian chemist is undoubtedly one of tho most significant scientific developments of the year. Mr. Ottar Rygh, the discoverer, has not only disclosed the chemical identity of this mysterious substance, but he has also pointed out a simple way of producing the vitamin substance in large quantities from cheap raw materials. The details of his experiments, in which more than 15,000 oranges were consumed to provide material for his research, have now been made public in a publication of the Fridtjof Nansen Foundation.

L As a result of Mr. Rygh's work narco- | tine lias been shown to be the pro-vita--1 min C which, upon the ripening of the fruit, is chemically changed into vitamin C which is found to be the chemical i known as orthodiphanol. Synthetic ortlioj diphenol, prepared in the chemical laboratory, has been shown to be active against scurvy in guinea pigs when 0.02 to 0.03 of a milligram is administered daily. The investigations that led to this result were carried out in the following way, states the Scientific American :

Raw juice, obtained from oranges by pressing, was centrifuged and gently evaporated in vacuum to about one-sixth of its original volume at a temperature not exceeding 25 degrees centigrade. The concentrated juice was shaken with ether to remove the small suspended oily particles; during this treatment the turbidity disappeared. A sodium hydroxide solution was then added in small portions with air excluded, until the reactions with litmus was very faintly alkaline. It was again extracted with ether and the extraction product evaporated to remove the ether, all operations being carried out in the absence of air.

The residue, which had a strong antiscorbutic power, consisted of a yellow oil mixed with needle-shaped crystals, which were shown to be narcotine. Extensive experiments led to the conclusion that the unripe fruit is rich in the narcotine and poor in vitamin C, while the ripe fruit is rich in vitamin, the narcotine disappearing during the ripening of the fruit.

The second part of the problem was to synthesise the vitamin from pure narcotine. Irradiation with ultra-violet rays was first tried, but only a slight change in the biological action of the substance was observed. Then an effort was made to change the narcotine by chemical treatment. After two hours' treatment of narcotine with strong hydrochloric acid, the monophenol is formed, and after six to seven days the orthodiphenol. The monophenol showed a slight anti-scorbutic action, whereas the orthodiphenol was found to be preventive of scurvy in guinea pigs when administered in doses of 0.02 of a milligram a day. When as much as 0.1 of a milligram a day was administered, symptoms of overdosage appeared. NEW TREATMENT FOR RUST Phosphoric acid is used to remove rust from iron and to prevent further rusting in a process developed by German chemists. The iron is first freed from all corrosion products by treatment in a 15 per cent phosphoric acid bath, and after washing with water, is treated for a short time in a 1 to 2 per cent phosphoric acid bath, kept as hot as possible. The etched iron parts usually dry by the. heat absorbed in the hot bath. A very thin phosphate layer is formed, which prevents fresh rusting. I his process, as described, or in a somewhat modified form, has found application m the bicycle industry, in pipe manufacture and iu the automobile iudustry. TWO GREAT COLLECTIONS Two great collections have recently been added to the Museum of Comparative Zoology at Harvard. Mr. John Elliot Thayer has presented his series of 30,000 specimens of bird skins, forming probably the finest private collection of North American birds. The collection also contains many thousands of nests and eggs. Some of the specimens are very valuable —extinct birds include the Labrador duck, the Eskimo curlew and the passenger pigeon. There are ten eggs of the extinct great auk, and several of the California condor, which is becoming very rare. The second collection, bequeathed by Andrew Gray Weeks, contains some 75,000 specimen's of butterflies and moths, many being type specimens. The former owner also left to the museum a fund for the care and increase of the collection.