# Antioxidant, Anti-Inflammatory, and Chemical Composition Analysis of In Vitro Huperzia serrata Thallus and Wild Huperzia serrata

## TL;DR

This study evaluates the potential of cultivated Huperzia serrata thallus as a sustainable alternative to wild Huperzia serrata for producing Huperzine A and antioxidant compounds.

## Contribution

The study identifies cultivated Huperzia serrata thallus as a viable alternative to wild plants with enhanced antioxidant and anti-inflammatory properties.

## Key findings

- Cultivated Huperzia serrata thallus (ST and OT) showed stronger antioxidant and anti-inflammatory activities than wild Huperzia serrata.
- ST demonstrated high radical scavenging activity (93.23% DPPH and 99.87% ABTS) and reduced nitrite production significantly.
- Metabolomic analysis revealed higher concentrations of phenolic acids and flavonoids in cultivated thallus, linked to antioxidant activity.

## Abstract

Huperzine A is a preferred treatment option for Alzheimer’s disease. Huperzia serrata (Thunb. ex Murray) Trev. (H. serrata) has garnered significant attention for its ability to produce Huperzine A (HupA). However, natural populations of wild H. serrata (WH) are rapidly declining. Fortunately, our group obtained two types of H. serrata thalli (OT and ST) capable of stably producing Huperzine A, which have the potential to serve as an alternative resource to WH. To evaluate the feasibility of this strategy, we conducted a comprehensive assessment of both WH and H. serrata thallus. The results indicated that compared to WH, ST and OT exhibited stronger anti-inflammatory and antioxidant activities, with lower cytotoxicity. Notably, ST demonstrated a strong radical scavenging activity, reaching 93.23% (DPPH at 0.2 μg/mL) and 99.87% (ABTS at 4 μg/mL), and reduced nitrite production from 10.29 μM to 6.51 μM at 50 µg/mL. GC-MS and widely targeted metabolomics analyses revealed that the higher antioxidant and anti-inflammatory activities for ST and OT were due to higher concentrations of phenolic acids and flavonoids compared to WH. In addition, the HupA content in ST reached 36.56% of that found in WH. KEGG enrichment analysis revealed that the flavonoid, phenylalanine, and phenylpropanoid biosynthesis pathways may be involved in regulating the antioxidant activity. P-coumaroyl quinic acid and caffeoyl quinic acid are the crucial metabolites for antioxidant activity. These findings suggested that the H. serrata thallus could serve as a sustainable alternative to WH.