Isolation and Identification of Hypotensive Substances in Chlorella Extract

Abstract

We attempted isolation of the hypotensive substance contained in hot water extracts of chlorella raw cells. When chlorella extracts were fractionated by gel filtration, fraction E showed a depressive effect. Blood pressure of SHR and SHRSP showed falls of about 60mmHg at 1 hour after intravenous administration and of 30 to 40mmHg at 2 hours after intragastric administration. Fraction E was subsequently purified by passage through a column of Sephadex G-10, and then crystallized from ethanol. Both the crystalline compound and the mother liquor showed hypotensive effects, but the effect of the latter was more potent. The crystalline compound was identified as adenosine by means of chemical and physical methods, and the mother liquor was considered to be a mixture of adenosine and an unknown compound containing glycine. As a result, the hypotensive effect of fraction E on SHR and SHRSP may be ascribable to adenosine or to an oligopeptide with a molecular weight of approximately 200.