Male Fern (Filix Mas) British Pharmacopoeia 1958

Compiled by Ivor Hughes.

MALE FERN (Filix Mas)
Male Fern consists of the rhizome, frond-bases and apical bud of Dryopteris filix-mas (L.) Schott, collected late in the autumn, divested of the roots and dead portions and carefully dried, retaining the internal green colour. It contains not less than 1-50 per cent of filicin.

Description. Odour, slight; taste, at first sweetish and astringent, but subsequently bitter and nauseous.

Macroscopical. Cylindrical-ovoid from about 7 to 15 cm. long and 3 to 4 cm. broad, the rhizome itself about 2 cm. in diameter; either entire or split longitudinally, externally dark brown to black, entirely covered with the hard, persistent, curved, angular, dark brown bases of the fronds, from 3 to 6 cm. long and 5 to 8 mm. thick, the frond bases, as well as the younger parts of the rhizome, bearing numerous ramenta; the fronds of the bud show circinate vernation. Transversely cut surface pale green and starchy, central ground tissue about 10 mm. in diameter, surrounded by an interrupted circle of about six to nine vascular strands of various sizes; cortex about 2 to 4 mm. wide, the whole enclosed by the cut bases of the fronds, each showing an arc or circle of six to nine small vascular strands.

Microscopical. Rhizome and leaf-bases with a hypodermal layer of a few rows of yellowish-brown, fibrous sclerenchymatous cells and parenchymatous ground tissue of rather thick-walled polygonal cells containing abundant small rounded starch grains up to about 18 to 25 microns in diameter, with numerous large intercellular spaces into which project shortly-stalked pyriform glands with external secretion; vascular system, dictyostelic; endodermis, including an outer layer of thick-walled elongated cells and an inner thin-walled parenchymatous layer; phloem, of large sieve tubes, with lateral sieve plates; xylem of prismatic tracheids, 10 to 50 microns in diameter, with scalariform or, rarely, spiral thickening and oblique end-walls. Ramenta with marginal teeth formed from outgrowths of two adjacent cells and no glands except at the base where there may be two, which are unicellular.

Acid-insoluble ash. Not more than 2-0 per cent.

Assay. Exhaust about 12-5 g., accurately weighed, in moderately coarse powder, by percolation with solvent ether; evaporate the percolate to about 40 ml. and complete the Assay described under Male Fern Extract, see below, commencing at the words 'Add 50 ml. of barium hydroxide solution.


Description. Brown. Diagnostic structures: parenchyma, of large cells containing numerous rounded starch grains, about 18 to 25 microns in diameter, with large intercellular spaces which show unicellular stalked pyriform glands with external secretion of oleo-resin; yellowish-brown hypodermal sclerenchymatous cells about 300 to 700 microns in length; tracheids, scalariform; fragments of ramenta, with marginal teeth. Calcium oxalate, absent.

Standard for filicin; Acid-insoluble ash. Complies with the requirements for filicin, and Acid-insoluble ash stated under Male Fern.

Preparations. Male Fern Extract. Male Fern Extract Capsules.

Extractum Filicis. Male Fern Ext. Ext. Filic. Male Fern Extract contains not less than 21-0 per cent w/w and not more than 23 -0 per cent w/w of filicin. Exhaust Male Fern, in moderately coarse powder, by percolation with Solvent Ether; remove the ether and evaporate the remainder of the percolate on a water-bath until an oily extract remains. Determine the proportion of filicin in a portion of the extract by the Assay described below. To the remainder add, if necessary, sufficient Arachis Oil, or other suitable official fixed oil, to produce an extract of the required strength.

Description. A thick, greenish-brown liquid, frequently containing a granular sediment.

Solubility. Miscible with acetone, with chloroform, with solvent ether, and with fixed oils.

Weight per ml. At 20�, not less than 0-995 g.

Assay. Dissolve about 1-0 g,, accurately weighed, of a well mixed sample in 20 ml. of solvent ether and transfer to a separator with the aid of a further 20 ml. of solvent ether. Add 50 ml. of barium hydroxide solution, shake vigorously for five minutes, and allow to separate. Filter the aqueous liquid, wash the ethereal liquid with two quantities, each of 5 ml., of water, and filter the washings through the same filter paper. Acidify the combined aqueous liquid and washings with hydrochloric add and extract with 30, 20, 15, and 10 ml. of chloroform. Mix the chloroform solutions, add 2 g. of anhydrous sodium sulphate, shake, and filter. Wash the anhydrous sodium sulphate and filter with two quantities, each of 5 ml., of chloroform. Evaporate the combined chloroform solutions and washings to dryness and dry the residue of filicin to constant weight at 100�.

Storage. Male Fern Extract should be kept in a well-closed container and should be thoroughly stirred or shaken before use.

Preparation. Male Fern Extract Capsules, see below. DOSE. 3 to 6 ml. (45 to 90 min.), after a period of twenty-four hours' starvation.

Capsulas Extracti Filicis Male Fern Ext. Caps. Caps. Ext. Filic.

Male Fern Extract Capsules are flexible capsules, the shells of which are coloured black. The average volume of male fern extract in each capsule, as determined by the Assay described below, is not less than 95-0 per cent and not more than 105-0 per cent of the prescribed or stated amount of Male Fern Extract. The contents of the capsules reserved in the Assay comply with the following test:

Content of filicin. Not less than 21-0 per cent w/w and not more than 23-0 per cent w/w, when determined by the Assay described under Male Fern Extract.

Assay. Weigh 20 capsules. Open the capsules carefully without loss of shell material, express as much of the contents as possible, and reserve the expressed material; wash the shells with solvent ether, reject the washings, allow the shells to stand at room temperature until the odour of ether is no longer perceptible, and weigh. The difference in the weighings is equivalent to the weight of the total contents. Calculate the average volume of male fern extract in each capsule, assuming a weight per ml., at 20�, of 1-000.

DOSE. Male Fern Extract, 3 to 6 ml. (45 to 90 min.), after a period of twenty-four hours' starvation.

If the quantity to be contained in a capsule is not stated, capsules containing, in each, 15 min. of Male Fern Extract shall be dispensed or supplied.