# Stilbene Glycosides in Pinus cembra L. Bark: Isolation, Characterization, and Assessment of Antioxidant Potential and Antitumor Activity on HeLa Cells

## TL;DR

This study isolates two stilbene glycosides from pine bark and finds they have strong antitumor effects on HeLa cells despite weak antioxidant activity.

## Contribution

The study isolates and characterizes two new stilbene glycosides from Pinus cembra bark and evaluates their antitumor activity on HeLa cells.

## Key findings

- Resveratroloside and pinostilbenoside showed lower antioxidant activity compared to the raw bark extract.
- The compounds significantly reduced HeLa cell viability and suppressed proliferation more effectively than the extract.
- Structures of the glycosides were confirmed using NMR and MS analyses.

## Abstract

Stilbenes are plant secondary metabolites with remarkable antidiabetic, anti-inflammatory, antimicrobial, antioxidant, antitumor, and neuroprotective properties. As these compounds are valuable constituents in healthcare products and promising drug candidates, exploring new sources of stilbenes is essential for therapeutic advancement. The present study reports the isolation of two stilbene glycosides, resveratroloside and pinostilbenoside, from Pinus cembra L. bark. Their antioxidant activity and cytotoxic effects against HeLa cells were evaluated in comparison to the raw bark extract. The structures of resveratroloside and pinostilbenoside were confirmed by nuclear magnetic resonance (NMR) and mass spectrometry (MS) data analyses. Antioxidant activity was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power assays. Cell viability, apoptosis, cell proliferation, and cell cycle assays were used to evaluate the cytotoxic potential against HeLa cells. Resveratroloside and pinostilbenoside exhibited lower activity as free radical scavengers and reducing agents. However, they showed greater efficacy in reducing viability and suppressing proliferation in human cervical carcinoma HeLa cells. Given the promising findings of our study, the therapeutic potential of resveratroloside and pinostilbenoside should be further investigated.