Anthraquinones from the Roots of Aloe Gilbertii and Aloe Eleganis

Abstract

Aloe gilbertii and Aloe eleganis are endemic to Ethiopia, and Northern Ethiopia and Eritrea, respectively, where the leaf latex and root are traditionally used for the treatment of malaria, hepatomegaly, splenomegaly, diabetics and abdominal pain, leishmanaiasis and wound healing. Phytochemical screening tests of the CH₂Cl₂/CH₃OH (1:1) root extract of Aloe gilbertii revealed the presence of alkaloids, anthraquinones, terpenoids, flavonoids and the absence of tannins, saponins and steroids while CH₂Cl₂/CH₃OH (1:1) root extract of Aloe Elegans revealed the presence of anthraquinones, terpenoids, phenols, saponins, tannins, glycosides whereas flavonoids, alkaloids and steroids are absent. Chromatographic separation of CH₂Cl₂/CH₃OH (1:1) root extract of Aloe gilbertii yielded geranyl benzoate derivative (1) and 8-methoxy chrysopanol (2) whereas aloesaponarin I (3) and aloesaponol I(4) were isolated from roots of Aloe eleganis. Complete characterizations of the isolated compounds were done with the help of spectroscopic techniques (UV-Vis, IR, ¹H NMR, ¹³C NMR, DEPT-135, COSY, gHMBC and gHSQC).

Keywords: Aloe gilbertii, Aloe eleganis, Anthraquinones, Phytochemical screening