The process has been the subject of a considerable amount of investigation, numerous attempts having been made to actually separate the active fat-splitting constituent of the seeds, or to obtain it in a purer and more concentrated form than is furnished by the seeds themselves. Nicloux (_Comptes Rendus_, 1904, 1112, and _Roy. Soc. Proc._, 1906, 77 B, 454) has shown that the hydrolytic activity of castor seeds is due entirely to the cytoplasm, which it is possible to separate by mechanical means from the aleurone grains and all other cellular matter. This active substance, which he terms "lipaseidine," is considered to be not an enzyme, though it acts as such, following the ordinary laws of enzyme action; its activity is destroyed by contact with water in the absence of oil. This observer has patented (Eng. Pat. 8,304, 1904) the preparation of an "extract" by triturating crushed castor or other seeds with castor oil, filtering the oily extract, and subjecting it to centrifugal force. The deposit consists of aleurone and the active enzymic substance, together with about 80 per cent. of oil, and one part of it will effect nearly complete hydrolysis of 100 parts of oil in twenty-four hours. In a subsequent addition to this patent, the active agent is separated from the aleurone by extraction with benzene and centrifugal force. By the use of such an extract, the quantity of albuminoids brought into contact with the fat is reduced to about 10 per cent. of that in the original seeds, and the middle layer between the glycerine solution and fatty acids is smaller and can be saponified directly for the production of curd soap, while the glycerine solution also is purer. In a further patent Nicloux (Fr. Pat. 349,213, 1904) states that the use of an acid medium is unnecessary, and claims that even better results are obtained by employing a neutral solution of calcium sulphate containing a small amount of magnesium sulphate, the proportion of salts not exceeding 0.5 per cent. of the fat, while in yet another patent, jointly with Urbain (Fr. Pat. 349,942, 1904), it is claimed that the process is accelerated by the removal of acids from the oil or fat to be treated, which may be accomplished by either washing first with acidulated water, then with pure water, or preferably by neutralising with carbonate of soda and removing the resulting soap. Lombard (Fr. Pat. 350,179, 1904) claims that acids act as stimulating agents in the enzymic hydrolysis of oils, and further that a simple method of obtaining the active product is to triturate oil cake with its own weight of water, allow the mixture to undergo spontaneous proteolytic hydrolysis at 40 deg. C. for eight days, and then filter, the filtrate obtained being used in place of water in the enzymic process.