Louise Isager Ahl:
Polysaccharide diversity across the genus Aloe

Date: 22-02-2019    Supervisor: Nina Rønsted

Aloes have been used in traditional medicine for centuries, and Aloe vera is today a worldwide herbal product. One of the major chemical components of aloes are the polysaccharides found in the inner leaf mesophyll, often referred to as Aloe gel. Despite the extended use of Aloe vera and other aloes, little is still known about the polysaccharide composition and therapeutic value of the more than 500 species in the genus. High-throughput microarrays have been optimised and used for the comparative mapping and identification of polysaccharides in Aloe leaf mesophyll.

In chapter I, Comprehensive Microarray Polymer Profiling (CoMPP) was optimized and demonstrated to be a successful highthroughput screening method of Aloe inner leaf mesophyll tissue for basic research and potential authentication of Aloe herbal products.

In chapter II, microscope analyses revealed that hydrenchyma cell walls fold in a highly organised manner during drought, suggesting predetermined cell wall mechanics in remobilization of stored water and polysaccharides.

In chapter III, a CoMPP analysis showed seasonal changes in the polysaccharide composition over a year within the investigated species. This could be of importance for commercial cultivation in optimizing farming conditions and harvest times to obtain higher yield of relevant polysaccharides (Ahl et al., 2019a).

Finally, in chapter IV, CoMPP analyses of inner leaf mesophyll from 94 species of Aloe showed a strong correlation between polysaccharide profiles and habit type possibly reflecting the functional role of polysaccharides in cell wall structure.