Evolution and metabolites in lichenised Trentepohliales

Members of the green algal order Trentepohliales occur in diverse habitats with fluctuating levels of air humidity, where they can contribute to species-rich cryptogamic associations. Beside their abundance as free-living organisms in humid situations, Trentepohliales constitute the photobionts of approximately half of the lichenized fungi, and are especially important and likely diverse in lichens of the humid tropics. Despite their ecological importance, neither the phylogenetic relationships nor the symbiont association patterns are understood, which will be a major focus of this project. Lichenized and non-lichenized Trentepohliales produce a great variety of interesting metabolites, e.g. photosynthetic pigments (different chlorophylls, carotenoids like astaxanthin). Astaxanthin (former haematochrome) plays a protective role against UV light as an adaptive response against oxidative stress. It is thought that it functions as a very potent antioxidant against the oxigen radicals that are formed by photooxidation. It turned out that astaxanthin (nature`s super carotenoid) and further beneficial carotenoids show manifold biological activities and open up a wide market of applications. A biotechnological approach, by using optimised culture conditions (nutrient media, light) to maximise the productivity of Trentepohlia cells for carotinoids (e.g. astaxanthin) will be performed. The chemical properties of the pigments will be determined by HPLC (TLC). Although natural sources of carotinoids (astaxanthin) are numerous, nearly all are found in very low concentrations. We are very positive that Trentepohlia could be established as a potential source of carotenoids or other metabolites, as it accumulates a large quantity of valuable compounds. We already have introduced successful culture methods for Trentepohlia that can be scaled up, easily.

Members of the green algal order Trentepohliales occur in diverse habitats with fluctuating levels of air humidity, where they can contribute to species-rich cryptogamic associations. Beside their abundance as free-living organisms in humid situations, Trentepohliales constitute the photobionts of approximately half of the lichenized fungi, and are especially important and likely diverse in lichens of the humid tropics. Despite their ecological importance, neither the phylogenetic relationships nor the symbiont association patterns are understood, which will be a major focus of this project. Lichenized and non-lichenized Trentepohliales produce a great variety of interesting metabolites, e.g. photosynthetic pigments (different chlorophylls, carotenoids like astaxanthin). Astaxanthin (former haematochrome) plays a protective role against UV light as an adaptive response against oxidative stress. It is thought that it functions as a very potent antioxidant against the oxigen radicals that are formed by photooxidation. It turned out that astaxanthin (nature`s super carotenoid) and further beneficial carotenoids show manifold biological activities and open up a wide market of applications. A biotechnological approach, by using optimised culture conditions (nutrient media, light) to maximise the productivity of Trentepohlia cells for carotinoids (e.g. astaxanthin) will be performed. The chemical properties of the pigments will be determined by HPLC (TLC). Although natural sources of carotinoids (astaxanthin) are numerous, nearly all are found in very low concentrations. We are very positive that Trentepohlia could be established as a potential source of carotenoids or other metabolites, as it accumulates a large quantity of valuable compounds. We already have introduced successful culture methods for Trentepohlia that can be scaled up, easily.