Polypeptides of the Three Major Medicinal Aloes

Major polypeptide species of proteins have been identified and analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE) in fresh extracts of the gel portion of mature leaves of Aloe saponaria Haw, Aloe barbadensis Miller, and Aloe arborescens Miller var. natalensis Berger. Extracts of gel from freshly cut Aloe leaves were prepared by dissection, tissue disruption, ethanol extraction, differential centrifugation, and gel filtration methods. Comparisons of SDS‐PAGE profiles of Aloe leaf gels showed that all three medicinal Aloes share five major common polypetides. Other results indicated that Aloe saponaria and Aloe barbadensis share the most major polypeptides, i.e. 11, and Aloe barbadensis and Aloe arborescens the least, i.e. 5, while Aloe arborescens had three individual polypeptides not found in the other two species. This is the first report to describe the nature and types of polypeptides detected in extracts of leaf gel portions of mature Aloe plants of these three medicinal species. Accordingly, this report may be of considerable value in helping to identify and characterize those Aloe substances of medicinal importance which are associated with each or all of these medicinal Aloes.