41 



R\RT VI - ECONOMIC CONSIDERATIONS IN THE UTILIZATION OF STARFISH 



By Charles F. Lee*"* 



INTRODUCTION 



Previous papers have discussed the relation of the common starfish ( Asterias 

 forbesi ) to the oyster industry and the phases of starfish utilization which have 

 been investigated by the U.S. Fish and Wildlife Service. The economic considerations 

 involved in any practical utilization of starfish have been mentioned only briefly 

 before. It is the object of this, concluding section to investigate this important 

 phase of the general problem of the utilization of starfish in the New England area. 



SUMMARY OF POTENTIAL USES FOR STARFISH 



Briefly, the investigations of the Fish and Wildlife Service have been con- 

 firmed by several other investigators with respect to the value of starfish meal 

 as a feedstuff. It was found to be a valuable protein supplement in amounts up to 

 6 percent by weight of growing mashes for chicks. In addition, starfish meal 

 satisfactorily supplied both protein and lime in laying mashes at a level of 8 

 percent. Raw starfish as well as meal dried at low temperatures were found to 

 contain thiaminase, the thiamine-destructive enzyme. This added a new phylum of 

 marine organisms to the list of those with members containing thiaminase. Raw 

 starfish used as fertilizer supply about 1.3 percent available nitrogen and 3.5 

 percent of acid soluble calcium. Treatment with sulfuric acid does not, however, 

 solve any of the problems involved in handling and storing large quantities of 

 raw starfish. 



The proximate, analysis of starfish does not indicate any other way in which 

 starfish might be used. Starfish oil must be solvent extracted as it averages 

 about 2 percent and rarely exceeds 3 percent of the freshly caught material. The 

 oil has been found to contain a complex mixture of virtually inseparable sterols 

 (see Part II). So far as is known, none of these sterols shows promise as inter- 

 mediates in the fields of vitamin or hormone chemistry. Only the existence of a 

 high-priced byproduct would justify the costly solvent extraction of the small 

 amount of oil available. Thorough investigation of the protein of starfish offers 

 some promise of discovery of a product of high value. The protein is readily 

 broken down and might prove to be a source of certain amino acids which have re- 

 cently been in considerable demand fo r clinical studies and nutrition research. 

 *Chemical Engineer, Fishery Technological Laboratory, Branch of Commercial Fisheries, College 



Park, Maryland. 

 NOTE: Part I of this series, "Starfish Control — Its Economic Necessity and Methods Used," 

 appeared in the January 1948 issue of Commercial Fisheries Review , pp. 1-6. Also available 

 as Sep. No. 193. 



Part II, "Chemical Composition," appeared in the February 194° issue, pp. ll-lo. Also 

 available as Sep. No. 196. 



Part III, "Value of Starfish Meal — Protein Supplement for Growth of Bats and Chicks and 

 for Egg Production," appeared in the March 1948 issue, pp. 8-19. Also available as Sep. 

 No. 199. 



Part IV, "Tniaminase in Starfish," appeared in the May 1948 issue, pp. 12-19. Also 

 available as Sep. No. 204. 



Part V, "Starfish as Fertilizer," appeared in the June 1948 issue, pp.ll-l6. Also 

 available as Sep. No. 206. 



