Work

Response of Melissa officinalis subsp. officinalis seedlings to Fe 3 O 4 ‐ NPs under in vitro conditions: physiological, biochemical and molecular analyses

Year: 2025

Type: article

Abstract: Application of iron oxide nanoparticles (NP) (Fe 3 O 4 ‐NPs) in plant biotechnology presents new opportunities for enhancing metabolic activity of medicinal plants; however, their specific effects on Melissa officinalis subsp. officinalis remain poorly understood. This study examined effects of Fe 3 O 4 ‐NPs at 0, 25, 50, 75, and 100 mg L −1 on morphological traits, phenolic compound accumulation, antioxidant activity, enzyme inhibition, and expression of PAL, TAT and RAS genes under in vitro conditions. Seeds were germinated on Murashige & Skoog medium and cultured for 30 days. Morphological characteristics were measured, total phenolics and flavonoid content were quantified spectrophotometrically, and phenolic profiles determined via HPLC. Antioxidant activity (CUPRAC, DPPH, ABTS), enzyme inhibition (AChE, MAO‐A, urease), and gene expression (qRT‐PCR) were also assessed. Treatment at 25 mg L −1 yielded the highest content of total phenolics (41.68 mg GAEg −1 plant) and rosmarinic acid (22.10 μg mg −1 DW), together with improved antioxidant, MAO‐A (2.95 mg plant mL −1 ) and urease (6.71 mg plant mL −1 ) inhibition activity. Higher concentrations (75–100 mg L −1 ) increased AChE inhibition but reduced antioxidant capacity. PAL, TAT, and RAS expression was upregulated in all treated groups: PAL peaked at 25 mg L −1 , RAS at 100 mg L −1 , and TAT at 75 mg L −1 . There was no direct correlation between gene expression and phenolic levels, suggesting involvement of post‐transcriptional or alternative regulatory mechanisms. These results demonstrate that Fe 3 O 4 ‐NPs act as dose‐dependent modulators of secondary metabolism and bioactivity in M. officinalis , offering promising tools for nanoparticle‐based elicitation strategies in medicinal plant biotechnology.

Source: Plant Biology

DOI: 10.1111/plb.70158

Authors: E. Bektaş, H. Şahin, H. İ. Güler, K. İ. Bektaş, K. Kaltalioğlu, N. E. Uzun

Institutions: Giresun University, Karadeniz Technical University

Language: English

Topic: Nanoparticles: synthesis and applications

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

SDG: Zero hunger

Open Access status: hybrid

Estimated APC paid: $3,400