Novel methods to characterise spatial distribution and enantiomeric composition of usnic acids in four Icelandic lichens

Maonian Xu, Ernest Oppong-Danquah, Xiaoyu Wang, Sebastian Oddsson, Asmaa Abdelrahman, Simon Vilms Pedersen, Maria Szomek, Aron Elvar Gylfason, Bergthóra S. Snorradóttir, Eva Arnspang Christensen, Deniz Taşdemir, Cynthia J. Jameson, Sohail Murad, Ólafur S. Andrésson, Kristinn P. Magnússon, Hugo de Boer, Margrét Þorsteinsdóttir, Sesselja Ómarsdóttir, Starri Heiðmarsson, Elín Soffia Ólafsdóttir