# Chemical Profile, Antimicrobial and Anti-AChE of the Volatile Fraction of the Unexplored Bryophyte Polytrichadelphus purpureus Mitt. from Ecuador

## TL;DR

This study explores the chemical and antimicrobial properties of a rare bryophyte from Ecuador, identifying its volatile compounds and their potential bioactivity.

## Contribution

The paper reports the first chemical and bioactivity analysis of the volatile fraction of Polytrichadelphus purpureus.

## Key findings

- The volatile fraction contains 86 compounds, with sesquiterpene hydrocarbons, alcohols, and alkanes as major groups.
- The volatile fraction showed moderate antimicrobial activity against Gram-positive bacteria and a fungus.
- It exhibited weak acetylcholinesterase inhibition, but not enough to suggest therapeutic use alone.

## Abstract

Polytrichadelphus purpureus is a bryophyte distributed in tropical and subtropical regions. It represents an underexploited source of bioactive metabolites. In this study, the volatile fraction (VF) obtained by steam distillation was analyzed by gas chromatography (GC-MS and GC-FID) on a DB-5ms capillary column, identifying 86 volatile compounds, representing the 97% of the volatile profile. Sesquiterpene hydrocarbons (23.6%), alcohols (15.6%), and alkanes (14.1%) were the major group compounds. Major components include (Z)-falcarinol (14%), hexacosane (4%), β-Curcumene (3%), and oleic acid (3%), among others. In addition, the volatile fraction exhibited moderate in vitro inhibitory activity against Gram-positive bacteria (E. faecium, S. aureus), fungus A. niger at concentrations of 250 µg/mL and 500 µg/mL, respectively, and E. faecalis and L. monocytogenes (250–500 µg/mL) and a weak inhibition of acetylcholinesterase (IC50: 392 µg/mL). These effects were evaluated for the first time in this species. While they are within the range reported for other plant-derived volatile fraction, they do not, on their own, justify claims of therapeutic efficacy. This study primarily advances our understanding of the genus Polytrichadelphus, suggesting potential as a source of bioactive sesquiterpenes for future phytochemical screening.