Brachythecium rutabulum, A Neglected Medicinal Moss

The search for new pharmaceuticals from naturally occurring biological materials has been guided by ethnobiological data. The investigation of folk medicine is a valuable tool in bioprospecting for pharmaceutical compounds (Costa-Neto 2002), and natural product drug development is key to the pharmaceutical industry. Over the past decade, research on medicinal plants has increasingly used historical medicobotanical texts both to study the development of pharmacopoeias as well as to identify candidate species for drug development (Staub et al. 2016). The first medicinal bryophytes were noted in the first century and subsequently a relatively large number of species in the phylum Bryophyta have been recognized in medicinal usage since the sixteenth century (Drobnik and Stebel 2014, 2015). In 1600, Caspar Schwenckfeld listed six botanical names for bryophytes, which specified at least four species used as remedies in folk medicine (Drobnik and Stebel 2015). Cooper (2010) concluded that Catalogues of flora from specific European regions were published to provide local resources for the distribution and use of medicinal plants. Indigenous plants could be substituted for the exotic, often unavailable or unaffordable Materia Medica. Examples include the Harz Mountains (Thal 1588), Silesia (von Schwenckfeld 1600), Pomerania (Ölhafen 1643, 1656), and East Prussia (Loesel 1654). Since Galen’s first century works listed mostly Italian medicinal plants, these books enabled local inhabitants, including pharmacists and physicians, to harvest medicinal raw materials locally (Cooper 2010). Historical medical applications of some species bryophytes listed in these catalogues correspond with today’s pharmacological knowledge of the herb (Asakawa 2007; Asakawa et al. 2013; Drobnik and Stebel 2014, 2015, 2017). Medicinal plants described in historical sources can be identified by means of a chain of synonymic botanical names (mostly pre-Linnaean), which can be cross-checked with modern knowledge of species morphology, taxonomy, phytochemistry, and ethno-pharmacology (see Drobnik and de Oliveira 2015). Information on ethno-medical and historical uses of bryophytes has been collected to target modern pharmacological research by selecting potential candidate species as medicinal plant sources (Pant 1998; Podterob and Zubets 2002; Glime 2006; Harris 2008; Bowman 2016). Historical works have frequently provided information useful for modern medicinal therapies. For example, Adams et al. (2011) identified apparently lost Renaissance antimalarial remedies with proven antiplasmodial activity. The diuretic action of Polytrichum moss, known in seventeenth century Europe and independently used in traditional Chinese and Guatemalan medicine, was rediscovered in the nineteenth and early twentieth century (Drobnik and Stebel 2015), when Sphagnum moss was used for dressing wounds in 1882, and subsequently used in World War 1 simply as an absorbent. Medicinal use of Sphagnum peat was reported in folk * Jacek Drobnik [email protected]