SCIENCE 



[Vol. LV, No. 1427 



Council Committee on Salt Requirements of 

 Plants) each plant would receive 57 c.e. per 



Sam F. Trelease 

 Burton E. Livingston 

 Laboratory of Plant Physiology, 

 The Johns Hopkins TJniveksity, 

 March 23, 1922 



NOTE ON THE SYNTHESIS OF ETHYL 

 BUTYRATE IN EGG SECRETION 



In our analyses of egg secretion, Miss Wood- 

 ward"- and I- have isolated an enzyme of the 

 lipase group. The material, precipitated as a 

 white powder, is soluble in Jaoth sea-water and 

 fresh. In the presence of this "lipolysin," 

 droplets of egg £af decrease in diameter while 

 the hydrolysis of other neutral fats and the 

 cleavage of ethyl butyrate are measurably ac- 

 celerated.^ 



Since lipolysin is a parthenogenetic agent -j^- * 

 since the unmodified egg-secretions also have 

 parthenogenetic^ and lipolytic^ powers; and 

 finally, since eggs with secretions removed by 

 brief exposure to charcoal are completely 

 sterile,^ it seems liliely that lipolysis plays 

 some role in the normal initiation of develop- 

 ment.'^ However, the evidence that egg-secre- 

 tions have these powers is still incomplete. It 

 has not been reported whether, under condi- 

 tions significant for fertilization theory, the 

 effects already observed are reversible. 



Accordingly, I prepared egg-secretion as 

 free from contamination as possible and used 

 chloroform to inhibit bacterial action. To 10 

 or 15 c.e. of this, I then added, in one set of 

 experiments, .5 c.e. of absolute ethyl alcohol; 

 in another, 5 c.e. of 2N. Butyric acid was intro- 

 duced last of all. The final concentration of 

 the acid was roughly .25 N". and .4 N. 



The acidity of the systems was, of course, 

 immediately reduced by the salts present in 

 both the secretion and the sea-water. Under 

 the circumstances then, the loss in total acidity 

 has no meaning for the problem in hand. Only 



1 Woodward: J. Exp. ZooL, Vol 26, pp. 459-501. 

 sGlaser: Am. Nat., Vol. LV, pp. 368-373. 

 sGlaser: Biol. Bull, Vol. XLI, pp. 63-72. 

 * Woodward : Biol. Bull., Vol. XLI, pp. 276-279. 

 sGlaser: Biol. Bull., Vol. XXVI, pp. 387-409. 



differences are important, and, if in the pres- 

 ence of egg-secretion, a portion of the butyric 

 acid is transformed into butyric ester, the tubes 

 in which this occurs should require less alkali 

 than the controls in order to reach the turning 

 point. Ph., of di-brom-thymol-sulpho-phthalein. 



The differences of acidity actually found be- 

 tween 10 c.e. of control and 10 c.e. of digest, 

 in one case, after 40 minutes at 20° C, amount- 

 ed to .8 c.e. NaOH N/20; in another, after an 

 hour, to 2.4 c.e. NaOH ]Sr/20, in both instances, 

 in favor of the controls. 



Absolutely, these discrepancies are small, but 

 even greater differences might fail to be con- 

 vincing, for conceivably, the organic constitu- 

 ents of the secretion, still largely unknown, 

 might in some way destroy or otherwise remove 

 Ijutj'rie acid from the reaction system. For- 

 tunately, however, ethyl butyrate has an odor 

 so penetrating and characteristic that even 

 minute traces can be unmistakably detected. 

 By this delicate test, the ester, regularly absent 

 from the controls, was present in noticeable 

 quantities in the digests with secretion and was 

 easily recognized by others not familiar with 

 the experiments. For eighteen hours the ester 

 smell continued to grow in intensity. 



On the basis of these results, I attribute to 

 egg-exudate the power to accelerate the syn- 

 thesis of ethyl butyrate. This is neither more 

 nor less than might be expected since the same 

 exudate also accelerates the corresponding 

 hydrolysis. 



Otto Glaser 



Amherst College, 

 February 2, 1922 



NATIONAL ACADEMY OF SCIENCES 



At the annual meeting of the National Acad- 

 emy of Sciences held in the U. S. National 

 Museum, Washington, on April 24, 25 and 26, 

 papers were presented as follows: 



The new building of the National Academy and 

 the National Research Council: C. D. Walcott, 

 President of the Academy. The ereetion of a 

 magnificent building, costing $1,300,000, as the 

 home of the National Academy of Sciences and 

 the National Keseareh Council, will shortly be 

 begun on the square bounded by B and C streets, 

 21st and 22d streets, northwest, Washington. The 



