The constituents of the essential oil from the fruit of Pittosporum undulatum / by Frederick B. Power and Frank Tutin.

  • Power, Frederick B. (Frederick Belding), 1853-1927
Date:
[1906]
Catalogue details

Licence: In copyright

Credit: The constituents of the essential oil from the fruit of Pittosporum undulatum / by Frederick B. Power and Frank Tutin. Source: Wellcome Collection.

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    known to possess an exquisite fragrance, which, however, is quite distinct from that of the fruit, and resembles that of orange blossoms. In order to ascertain the nature of the odorous principle of Pitto- sporum fruit, Professor Threlfall subjected 50 kilograms of the entire fruit to steam distillation, and obtained therefrom about 180 c.c. of an essential oil. As the specific gravity of the latter was determined by him to be 0‘848 at 24°, the yield of oil would correspond to about 03 per cent, of the weight of the fruit. He then submitted about 60 c.c. of the oil to a single fractional distillation, but none of these fractions were further examined, and they were subsequently seut to Professor W. A. Tilden, of the Royal College of Science, London, together with a small quantity of the original oil. Through the kindness of Professor Tilden, these specimens were placed at the disposal of one of us for further examinatiou. The oil distilled by Professor Threlfall was stated by him to have been dried by means of fused calcium chloride, and the portion received by us amounted to about 160 grams. After further drying with anhydrous sodium sulphate, and filtering, it was rectified by distillation. The rectified oil was pale yellow and had a pleasant odour, suggestive of the presence of a considerable proportion of limonene. Its density was 0’8638 at 15°, and its optical rotation + 82°32' in a 1-dcm. tube. The oil was then subjected to a preliminary examination, but, as it had evidently undergone some change on keeping, we availed ourselves of the opportunity of having a larger quantity of the oil freshly distilled for us in Australia for the purpose of its more complete investigation. Although Professor Threlfall in his paper (loc. cit.) has indicated that the Pittosporum undulatum is common in the bush around Sydney, this appears at present not to be the case, and a supply of fruit sufficient for the distillation of the oil could only be obtained from private gardens, where the tree is cultivated on account of the fragrance of the flowers. The distillation was conducted during the months of December and January, just before the period of ripening of the fruit, and while it was still green. From 220 kilograms of the fruit, 960 grams of essential oil were obtained, corresponding to a yield of 0‘44 per cent. Experimental. The investigation here described was conducted entirely with the oil which had been freshly distilled for us in Australia, and the amount employed for this purpose was 900 grams. Lt is pale yellow, and has a pleasant odour resembling that of orange oil. After being dried with anhydrous sodium sulphate and filtered, it had a density of 0‘8615 at 15°/15°, and an optical rotation of + 74°4' in a 1-dcm. tube. It was insoluble in ten times its volume of 70 per cent, alcohol.