Origin. The rhizome of malefern, Nephrodium filix mas, Stremp. (Aspidium filix mas, L.) (Fam. Poly podiaceae) owes its vermifuge properties in part to small amounts of a volatile oil. This was first prepared by Bock3) in 1851 by distillation with water vapor. The yield varies according to the season. From air-dried rhizomes, collected freshly in June, Ehrenberg4) obtained 0,025 p. c. of oil; from material, collected during the months September to November, 0,04 to 0,045 p. c.
Properties. The volatile oil of malefern is a light yellow liquid with an intensive malefern odor and an aromatic, finally pungent taste. It is readily soluble in ether and absolute alcohol, d 0,85 to 0,86. The bulk of the oil distills between 140 and 250°. Above this temperature decomposition sets in, dark colored products coming over as high as 350°.
1) K. Mueller, footnote 5 on p. 3.
2) Volatile oils have also been prepared by C. E. Lohmann, footnote 4 p. 3, from the following liverworts: Fimbriaria Blumeana, Pellia epiphylla, Metzgeria furcata, Fegatella conica, Marchantia polymorpha, Lunularia vulgaris, Targionia hypophylla, Aneura palmata, Madotheca platyphylla. The yield varied between 0,01 and 0,9 p. c. of the dried material. The odor of the oils reminded of that of the respective liverworts. Small amounts of oil only were obtained, in several instances but a few drops. Hence very little could be ascertained about their chemical nature. Analyses revealed the ratio of carbon to hydrogen of 1 to from 1,51 to 1,61. This would seem to indicate that they belong to the terpene group.
3) Arch, der Pharm. 115 (1851), 262; Chem. Zentralbl. 1851, 497.
4) Arch, der Pharm. 231 (1895), 345.