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Chinese goldthread (Coptis chinensis Franch.), a member of the Ranunculales, represents an important early-diverging eudicot lineage with diverse medicinal applications. Here, we present a high-quality chromosome-scale genome assembly and annotation of C. chinensis. Phylogenetic and comparative genomic analyses reveal the phylogenetic placement of this species and identify a single round of ancient whole-genome duplication (WGD) shared by the Ranunculaceae. We characterize genes involved in the biosynthesis of protoberberine-type alkaloids in C. chinensis. In particular, local genomic tandem duplications contribute to member amplification of a Ranunculales clade-specific gene family of the cytochrome P450 (CYP) 719. The functional versatility of a key CYP719 gene that encodes the (S)-canadine synthase enzyme involved in the berberine biosynthesis pathway may play critical roles in the diversification of other berberine-related alkaloids in C. chinensis. Our study provides insights into the genomic landscape of early-diverging eudicots and provides a valuable model genome for genetic and applied studies of Ranunculales.

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Cobalt thin films composed of a large number of nanopetals were fabricated on the glassy carbon (GC) substrate by cyclic voltammetric deposition of Co 2+ ions on a glass carbon electrode (GCE). The hierarchical Co nanostructures were further used as the sacrificial template to acquire Pd (or Pt) thin film electrocatalysts with hierarchical architectures through the galvanic replacement reaction between Co nanopetals and chloropalladite (or tetrachloroplatinate). The as-prepared Pd (or Pt) thin films contain quantities of nanoparticles and many hollow Pd aggregates in the range of submicrometer to micrometer scale. The hollow Pd aggregates were found to burst in acidic solutions at potentials more negative than the hydrogen evolution potential since Pd absorbed too much hydrogen. As an electrocatalyst for the formic acid oxidation, the Pd thin films presented much higher catalytic activity than the Pt thin films with a similar architecture. An important reason is that the formic acid oxidation at the Pd nanostructures proceeds via a non-CO reaction pathway, while the reaction at the Pt nanostructures involves formation of CO-adsorbed species, which has been confirmed by the CO stripping voltammetric curves on Pd or Pt thin films. The as-prepared Pd thin films with hierarchical architectures are expected to be a promising electrocatalyst in direct formic acid fuel cells (DFAFCs).