Agro-residue bioactives as functional inputs for sustainable and low-waste food packaging systems

Did you know that a humble lichen from Chile could help revolutionize food packaging? Scientists have uncovered a treasure trove of natural compounds in Sticta caulescens using green chemistry.

In the quest for sustainable food packaging, researchers are turning to nature's own chemistry. A recent study focused on the Chilean lichen Sticta caulescens, aiming to unlock its wealth of secondary metabolites—the compounds that could serve as functional ingredients in low-waste packaging systems.

Using green chemistry approaches, the team compared two extraction methods: traditional maceration with methanol and microwave-assisted extraction (MAE) with ethyl lactate, a greener solvent. The analysis revealed 32 metabolites from maceration and 33 from MAE, spanning carbohydrates, aromatic compounds, acids, depsides, depsidones, dibenzofurans, lipids, anthraquinones, and triterpenes.

Maceration yielded a slightly higher extract percentage (6.3% vs 5.0%), but MAE was remarkably efficient, extracting an almost identical spectrum of metabolites with one unique compound detected only under those conditions. This highlights the method's selectivity and efficiency.

Beyond this single species, the study included a chemoinformatic and chemotaxonomic analysis across 12 Sticta species. Computational tools showed S. caulescens is one of the most chemically diverse, closely related to S. cordillerana, and part of a lineage characterized by rich scaffold diversity and shared biosynthetic pathways.

Key Points

• 32 metabolites from maceration, 33 from MAE
• Ethyl lactate MAE matches methanol efficiency
• S. caulescens among most chemically diverse Sticta