Metabolomic profile of Amaranthus palmeri S. Watson (Amaranthoideae, Amaranthaceae): Effect on enzymes related to metabolic syndrome

Background: Amaranthus palmeri is recognized as one of the most harmful weeds worldwide due to its aggressive spread and resistance to herbicides, complicating its control in agricultural systems. However, it may contain phytochemicals similar to those identified in other Amaranthus. Questions: What are the main phytochemical components in the polar extracts from leaves and inflorescences of A. palmeri? Do these polar organic extracts have the potential to inhibit enzymes associated with metabolic syndrome? Studied species: Amaranthus palmeri Study site and dates: Greenhouses at the Centro de Investigación Científica de Yucatán, Mérida, Yucatán, Mexico, in 2024. Methods: Betalains and polyphenols were extracted from the leaves and inflorescences of A. palmeri using MSPD. Betalain profiling was performed using LC-MS/MS, and polyphenols were quantified using HPLC-UV-DAD. Additionally, antioxidant capacity was assessed by DPPH assay and enzyme inhibition assays were conducted against α-glucosidase, α-amylase, and ACE. Results: Nine betalains were found with higher accumulation in inflorescences than in leaves, while 13 polyphenols were found in leaves, with flavonoids such as rutin and quercetin being the most prevalent. The extracts showed a significant amount of antioxidant capacity and enzyme inhibitory activity, with the leaf extracts showing greater bioactivity than inflorescence extracts. Conclusions: A. palmeri is a promising source of bioactive phytochemicals due to its antioxidant potential and its inhibitory effect on key enzymes involved in metabolic syndrome. These findings demonstrate that this species has added value beyond its conventional view of being harmful to agriculture and has potential applications in pharmacology and biotechnology.