Lichen Derived Products

The purpose of this book is to provide reference material that includes current developments along with a future outlook on the topic. It is divided into two sections; "Morphological Overview and Extraction Prospects" and "Trends and Applications". Part I contains four chapters that provide an overview and systematically discuss the physical morphology, suitability and extraction aspects of lichens and their secondary metabolites. Part II includes eight chapters that give in-depth insights on recent and valuable applications of lichen and their obtained products in several applied sectors, including ethnopharmacology, therapeutics, paper and dye, nutraceuticals, cosmetics, herbal industries, etc.

This revised and extended edition provides in-depth insights into the benefits and untapped potential of lichen-derived bioactive compounds. The whole spectrum of these compounds’ biological and medical functions, from antibiotic to antiviral and anti-carcinogenic properties, is presented. In addition, a new chapter discusses the anti-neurodegenerative and anti-diabetic activities of lichenic secondary metabolites. Given its scope, the book offers a valuable asset for students and researchers in this field.

Noted textile designer and lichen expert explains how to create and use dyes derived from lichens. Text covers history of the use of lichen pigments, safe dyeing methods, ecologically sound dyeing, and use of mordants, lichen identification, and more. Text also offers a fascinating history of Asian and European lichen pigments, Scottish, Irish, and Scandinavian domestic lichen dyes, and others.

Lichens are fascinating symbiotic organisms, biosynthesizing a broad spectrum of interesting secondary metabolites and polysaccharides. A considerable number of them have been found to exert biological activities, such as antibiotic, antimycobacterial, antiviral, anti-inflammatory, analgesic, antipyretic, antiproliferative, and cytotoxic effects. Only a very low percentage of “lichen substances” have been actually screened for their biological activities and their potential therapeutic applications in medicine. This is due to difficulties to obtain large quantities of lichens from nature, isolated lichen fungi and algae from cultures for extractions. Ten years ago, we have started to bypass these problems by introducing first traditional and then by exploring novel microbiological techniques and advanced molecular tools for our culture experiments. “Case studies” with selected cultured mycobionts and photobionts, accumulating considerable quantities of a focused compound, have been performed as tests for large-scale culturing, to be able to utilize facilities like phytotrons and bioreactors (small-scale bioreactors) for future approaches. Further studies have focused on the chemical identification of the metabolites from cultures and the genetic characterization of lichen PKS genes (Polyketide synthase genes). Another interesting group of lichen metabolites is cell wall polysaccharides. All lichen species investigated so far produce these polymers in considerable amounts and many of them have been shown to exhibit antitumor, immunostimulating, antiviral as well as other types of biological activity. Lichens polysaccharides are mainly of the following structural types: α-glucans (isolichenan, nigeran, pseudonigeran, and pullulan), β-glucans (lichenan, pustulan, laminaran, and lentinan-type glucan), galactomannans, and complex heteroglycans (galactoglucomannan, galactomannoglucan, rhamnopyranosylgalactofuranan, and glucomannan). Investigations on lichen polysaccharides were carried out using material extracted from the entire thallus with no mention of the origin of component polymers (fungal partner or photobiont). In order to understand the contribution of the symbiotic partners to the polysaccharide present in the lichen thallus, the carbohydrates produced by some aposymbiotically cultured mycobionts and photobionts (Trebouxia, Asterochloris, and Coccomyxa) were analyzed. The studies demonstrated that most of the polysaccharides previously found in the symbiotic thalli were also produced by the aposymbiotically cultivated fungal partner, while there were no similarities between the polysaccharides extracted from the photobiont with those from the respective lichen. Surprisingly, the photobionts synthesized very interesting polysaccharides, such as β-galactofuranan, mannogalactofuranan, rhamnopyranosylgalactofuranan, and an O-methylated mannogalactan. One of them was biologically active, having in vitro activity on murine peritoneal macrophages.

The Lichens covers the structure and development, physiology of the intact thallus, environmental response and effects, secondary metabolic products, and symbiont interactions of lichens. This book is divided into five parts encompassing 19 chapters. It also includes appendices consist of a taxonomic scheme, methods for isolating and culturing lichen symbionts and thalli, and methods for isolating and identifying lichen substances. The first part of this book describes the original fungal cell and its development into specialized cells of which the various tissues and thalli are composed. This is followed by discussions on sexual reproduction of ascolichens and basidiolichens and on systematic criteria for the definition of taxa in different hierarchical steps. This book also explains the types of propagules produced by lichens and the submicroscopical investigations of lichens, including phycobiont and mycobionts' substructure and symbiotic relationship. The second part of this book examines the physiological aspects of lichens. It includes discussions on metal cation uptake and translocation in vascular plants and on lichens' role in rock weathering and soil formation. This part also studies photosynthetic rates and nitrogen absorption and metabolism by the intact thallus of lichens. Succeeding chapters discuss physiological and morphological responses of lichens to the most important environmental factors and the relationship of these factors to lichen distribution. Substrate preferences of lichens and their causes and implications with regard to the ecology, distribution, and taxonomy of lichens are also examined. This text also discusses lichen thalli growth, methods of measurement, and factors influencing growth. Finally, the concluding parts deal with the biosynthesis of lichen substances, secondary metabolic products, and symbiotic relations of lichens to fungi and algae. This multi-authored book is an ideal source of information for researchers, teachers, and students who wish to broaden their knowledge in the diversity of lichenology.

Chemical and Botanical Guide to Lichen Products:

This Reference Work is devoted to plant secondary metabolites and their evolutionary adaptation to different hosts and pests. Secondary metabolites play an important biological role in plants’ defence against herbivores, abiotic stresses and pathogens, and they also attract beneficial organisms such as pollinators. In this work, readers will find a comprehensive review of the phytochemical diversity, modification and adaptation of secondary metabolites, and the consequences of their co-evolution with plant parasites, pollinators, and herbivores. Chapters from expert contributors are organised into twelve sections that collate the current knowledge in intra-/inter-specific diversity in plant secondary metabolites, changes in secondary metabolites during plants’ adaptation to different environmental conditions, and co-evolution of host-parasite metabolites. Among the twelve themed parts, readers will also discover expert analysis on the genetics and chemical ecology evolution of secondary metabolites, and particular attention is also given to allelochemicals, bioactive molecules in plant defence and the evolution of sensory perception in vertebrates. This reference work will appeal to students, researchers and professionals interested in the field of plant pathology, plant breeding, biotechnology, agriculture and phytochemistry.

This handbook is an indispensable tool for the isolation, identification and structural analysis of the approx. 700 substances currently known to occur in lichens. The first part covers all necessary methods for the analysis of lichen metabolites; the second part gives the analytical and spectroscopical data of all known lichen substances as well as a key to their identification and differentiation. Besides its high value for all chemists working with these substances as a basis for other products, the book serves as a chemotaxonomical key to the identification of lichen species and as a reference for all those who use lichens for the biomonitoring of environmental pollution.

Lichens have the capability to dissolve granite. They are very colorful; oranges, yellows, greens, blacks and whites adorn trees, bedrock and even gravestones. This field guide spotlights 120 species, shown in color photos with natural history text.