1 THE BOTRYOSPHAERIA RHODINA STORY [DOI: 10.13140/RG.2.1.4617.8803] Dr. Robert FH Dekker BOTRYOSPHAERAN: A fungal exocellular β-D-glucan with a difference ! Over a period of some fifteen years, research groups in Brazil led by Dr. Aneli de Melo Barbosa with myself as collaborator, studied various bioproducts produced by the ascomyceteous, endophytic fungus, Botryosphaeria rhodina. Among them was botryosphaeran, a new exocellular (1→3)(1→6)-β-D-glucan first described in 2003 [1]. Some 30+ publications on projects related to botryosphaeran have been published, and were developed by 70 students involving collaborations within Brasil and Canada. The work with Botryosphaeria sp. commenced in 1994 at Murdoch University (Perth, Western Australia) with Dr. Barbosa (post-doc Research Fellow) from Brazil, who collected the fungus (isolate MAMB-05) from a canker on a eucalypt tree [2]. At the time we were seeking suitable microbes that could play a role in bioremediation of aromatic/phenolic compounds, and esp., wood-decay fungi that were ligninolytic, and thus the enzymes produced by these fungi would be operative in remediation of aromatic compounds. We discovered that fungal isolate MAMB-05 could grow on high concentrations of various aromatic compounds, and up to 100 mM veratryl alcohol [3,4] without adversely suffering toxicity. This fungal isolate produced a constitutive laccase that could be induced to higher enzyme titres by various aromatic compounds, and esp., veratryl alcohol [5]. Some 10 years was spent studying the microbial physiology of laccase production [6]. Several papers were published on laccase, but that’s another story. In 1994 we found an exopolysaccharide (EPS) was produced when Botryosphaeria sp. was grown on basal medium [4], but its synthesis was affected (lower yields) when various aromatic compounds were incorporated into the nutrient medium to induce laccases [7]. The EPS was easily isolated (alcohol precipitation), and was partially characterized as a β-glucan of mixed linkage as deduced from enzymolysis with β-glucanases including Trichoderma cellulases [4]. The EPS was suspected at the time of having β-(1→3)(1→4)-glucosidic linkages. Ten years later the precise chemical structure was determined and was found to be a β-glucan with (1→3)(1→6)-linkages, which we named botryosphaeran [1]. The degree of branching (22-31%) depended upon the carbohydrates used as carbon source for fungal growth [8,9]. The branched substituents were identified as comprizing both single glucose