Laurus nobilis
A 2012 brazilian study tested 40 vegetal drugs with Duquenóis-Levine test and obtained false-positive results to Chilean boldo ("Peumus boldus Molina"), pot marigold ("Calendula officinalis L."), leather hat ("Echinodorus grandiflorus (Cham. &amp; Schltdl.) Micheli."), cecropia ("Cecropia hololeuca Miq."), lemon balm ("Melissa officinalis"), anise ("Pimpinella anisum L."), guaraná ("Paulinia cupana Kunth."), jaborandi ("Pilocarpus jaborandi Holmes.") and laurel ("Laurus nobilis L.").