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FIRST DIRECTION «-BUTANOL METMYLETHYLKETONE , AMMONIA WATER - 2-1 HOURS 



characteristic compositions of free amino 

 acids; second, to determine if the known 

 tuna larvae possessed the same free amino 

 acids as their respective adalts; and third, 

 to develop, if possible, a simplified ship- 

 board technique. 



2. Instead of trying to identify each specific 

 amino acid found in the muscle tissue of 

 these fish, emphasis was placed upon seek- 

 ing characteristic differences in the overall 

 chromatographic patterns of the amino acids 

 among the various species of tunas tested. 



3. Sannples consisted of small bits of muscle 

 tissue (approximately 8 mm. 3) and minute 

 quantities of fluid squeezed from muscle tis- 

 sues. They were placed directly upon the fil- 

 ter paper. 



4. Four different solvents were tested, with 

 n-butanol:acetic acid:water in a ration of 

 4:1:5 and n-butanol:methylethylketone: 17 N 

 ammonia:water in a ratio of 5:3:1:1 showing 

 the best results in both one- and two-dimen- 

 sional chron-iatograms. All experinnents 

 were made on Whatman No. 1 filter paper. 



Figure 10. - -Two-dimensional chromatogram of 

 larval yellowfin. 



the author feels that any conclusion on the use 

 of the technique in species identification of tunas 

 would be premature. The technique is not with- 

 out promise, however, as was noticed by the 

 difference in positions of spots in the two frigate 

 mackerels, which had been captured at the sanne 

 time and kept frozen an equal length of time. 

 Also, the close resemblance between adult and 

 larval skipjack, both of which had been frozen 

 immediately upon capture, is significant. 



Comparing the number of spots shown by 

 adult species other than skipjack with those de- 

 veloped with fresh-frozen skipjack, it is believed 

 that either the changes due to proteolytic enzyme 

 reaction may not have been as important as sus- 

 pected, or that the suspicion that these fish had 

 been taken at such widely differing time as to 

 cause noticeable changes in the amino acid com- 

 plex could have been unfounded. If so, the data 

 obtained are certainly encouraging. 



SUMMARY 



1. Both one- and two-dimensional chromotog- 

 raphy on paper were attempted: first, to see 

 if the various species of adult tunas possessed 



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FIRST DIRECTION «-BUTANOL METHYLETHYLKETONE : AMMONIA : WATER - 24 HOURS 



Figure ll.--Two-diinensional chromatogram of 

 larval skipjack. 



