18 THE ROLE OF ALGAE AND PLANKTON IN MEDICINE 



and byperborea. 10 * The action of therapeutic agents can be modified by 

 combining them with algin, which is free of nitrogen and possesses a low 

 ailergenicity. It lends itself well to incorporation into medications to be 

 injected, since alginic solutions are clear and colorless, soluble in hot or 

 cold water, and retentive of their smoothly flowing nature throughout 

 wide temperature ranges. By varying the algin concentration only slightly, 

 it is possible to control not only the viscosity, but also the rate of absorp- 

 tion and assimilation of medication. 105 One example is the delayed-action 

 algin-epinephrine mixture being used in allergic disorders. 106 Another 

 is its use in retarding the absorption of penicillin and various mycin 

 drugs. 107 In this connection, it is interesting to note that Suzuki 108 has 

 been able to produce anaphylaxis in guinea pigs by intraperitoneal injec- 

 tions of saline extracts of seaweeds common in the Japanese diet. Ouer, 

 on the other hand, has reported minimal human sensitivity on intradermal 

 injection of propylene glycol alginate in 50 allergic and 50 non-allergic 

 individuals. 109 



Differing results have also been reported on toxicity and other 

 adverse reactions. Millis and Reed 110 noted that sodium alginate does not 

 interfere with calcium absorption in healthy human adults. Gill and 

 Duncan 111 likewise observed no electrolytic alterations, nor any significant 

 gastrointestinal disturbances. Nilson and Wagner 112 fed sodium alginate 

 and propylene glycol alginate to dogs, mice, and chicks; they considered 

 these substances harmless and "nutritionally wholesome, but bulky." 

 Chenoweth 113 reported a high degree of toxicity in cats. On intraperitoneal 

 or intravenous injection of sodium alginate, he found large antemortem 

 intracardiac clots, as well as frequent indications of injury to the brain, 

 liver and kidney. He asserted, too, that sodium alignate thus given elevates 

 the erythrocyte sedimentation rate just as do the various gums. Chenoweth 

 also found much toxicity with the nitrate derivative, which also greatly 

 prolongs blood clotting time. The dialdehyde derivative of alginic acid 

 was somewhat less toxic. Solandt 114 reported sodium alginate toxic for 

 rabbits, while Frantz found the same with rats. 115 Blaine 116 considered 

 that alginates make a good absorbable surgical substance, capable of being 

 used as a gel, foam, or gauze with a minimum of local tissue reaction. 

 He also used laminarin as a surgical powder in place of talcum. 117 Some 

 of these disagreements in reported results may be due to product impurities 

 or to differences in test animals. Others may be caused by variation in the 

 source of materials; thus, Solandt and Franz both used Laminaria as the 

 origin of their alginates, whereas Ouer used Microcystis. 



