The paper gives a survey of the blue-green algae found in Japan and used as food, medicine and nitrogenous fertilizer. Since time immemorial four kinds (Aphanothece sacrum, Nostoc verrucosum, Nostoc commune, Blachytrichia quoyi) have been used for cooking purposes; yet it is only now that man is trying to cultivate a species, theAphanothece sacrum. Recently a bluegreen alga (Spirulina maxima), which is particularly rich in protein and vitamins and has always been eaten by the natives, became known in Africa. The medicinal effects of linolenic acid was examined connection with the circulation of fatty acid. Only two of the species analysed (Spirulina platensis, Arthrospira sp.) produce relatively large quantities of γ-linolenic acid. The effects of the nitrogen-producing blue-green algaTolypothrix tenuis were observed in over 40 rice fields in various regions in Japan. In some places a considerable increase in the yield was noticed, but this was never as high as in India. Presumably the difference can be traced back to 3 main factors: air temperature, alkalinity of the water and the amount of nitrogen fertilizer.
- 1 - sciences appliquees, technologies et medecines
- 2 - sciences biologiques et medicales
- 3 - sciences biologiques fondamentales et appliquees. psychologie
- 4 - ecologie animale, vegetale et microbienne