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IN a previous communication1, it was suggested that the Astrogenic activity of crude specimens of anol and of the mother liquor from these preparations may be due to the presence of a polymer possessing an extremely high degree of potency. The active substance has been isolated by the following procedure

IN the normal chemical resolution of amino-acids using organic bases, one optical antipode—corresponding to the less-soluble diastereoisomeric salt—can generally be obtained optically pure. The more soluble derivative remaining in the mother liquor is contaminated with a small amount of the less-soluble salt and is therefore always very difficult to obtain pure. The usual device of using both forms of the optically active base in turn is not feasible as only the natural occurring antipodes of the alkaloid bases (quinine, brucine, cinchonine, strychnine, etc.) are readily available.

DURING the recrystallization of pepsin by the method of Northrop1, which involves heating a solution of the enzyme to 45° C. at pH 4, followed by cooling, it was noticed that the warm solution deposited a considerable quantity of needle crystals totally different from crystalline pepsin; these were identified as tyrosine. Continued autolysis under these conditions yielded 35 mgm. of tyrosine in 24 hr. from 6 c.c. of a solution containing 1.0 gm. of dry pepsin. This represents approximately 40 per cent of the total tyrosine present. Investigation of the dialysed mother liquor by two-dimensional paper chromatography2,3 revealed the presence of at least thirty-four ninhydrin-positive substances (see diagram), many of which disappeared on acid hydrolysis, indicating that they are peptides. It is suspected that some of the spots are simple amino-acids, as indicated by their position and speed of development. Samples of the autolysing solution taken at 5-min. intervals during the first hour showed on paper chromatography with butanol acetic acid in one dimension that a very complex pattern of spots is present from the beginning, though extremely faint at first. Analysis in one dimension could not, of course, decide whether the initial pattern contains all the thirty-four spots finally detected; but it is provisionally concluded that the formation of the final fragments are not rate-determining steps.

A model plant of closed continuous flowing culture apparatus was devised and tested for the conditions of cultivation by using Chlorella vulgaris and compared a reformed medium with that of Tamiya's. The followings were revealed:1. Carbon dioxide concentration in the blowing air mixture was found enough below 1%.2. The inoculation quantity of Chlorella vulgaris was found enough with 0.1-0.3g/L.3. In this apparatus system combined with 3 tubs, the yield of Chlorella was about 68g/day after 4 days from the inoculation of about 0.1g/L, while it was about 48g/day by the batch system culture.4. The major components of Tamiya's medium, NO3-N, K+, Mg2+, H2PO4-P were decreased to about 1/10 and the reformed formula was found convenient to a flowing cultivation, because there were settled out no crystals from these minerals as in the case of Tamiya's according to the pH transference into alkaline during the multiplication.The mother liquor removed from the alga was repeatedly available to the culture on adding any decreased components. Consequently, the reformed medium was found convenient to this closed continuous-flowing culture apparatus system.