Skin-lightening metabolites in Achillea filipendulina: comparative phytochemical and bioactivity profiling of extracts from shoot cultures and field-grown plants

Achillea filipendulina, a polyphenol-rich species, was used to establish in vitro shoot cultures and to compare their phytochemical and biological properties with those of field-grown material. In vitro shoots cultivated on agar medium (AFiv) and in Plantform bioreactors (AFB) were extracted with ethanol, 50% ethanol, or water and evaluated alongside extracts from field-grown plants (AFH). HPLC ESI QTOF MS/MS profiling revealed 37 phenolic constituents. At the same time, quantitative analysis by LC-MS confirmed that chlorogenic acid was the major compound, reaching the highest concentrations in AFH and AFB ethanol based extracts. In contrast, AFiv samples contained lower but consistently detectable levels. Similarly, p hydroxybenzoic acid, quercetin, and rutin were quantified above LOQ in nearly all samples, with their highest amounts in AFH EtOH and 50% EtOH extracts and the lowest levels in AFiv H₂O extracts, demonstrating clear solvent and biomass dependent variation. AFH extracts showed the strongest antioxidant activity (IC₅₀ 50% EtOH=30.1; TPC=1.32 mg GAE/g DW), while AFiv and AFB displayed lower TPC (0.36–0.38 and 0.19-0.30 mg GAE/g DW) and weaker activity (IC₅₀=254->1000µg/mL). In tyrosinase assays, AFiv extracts were the most potent, inhibiting murine tyrosinase by 56.8–62.8% and human tyrosinase by 17.6–29.9%, comparable to kojic acid, whereas AFH and AFB demonstrated weaker or selective inhibition. Cytotoxicity testing showed that AFH extracts reduced HaCaT viability by 25–38%, while AFiv and AFB were non-cytotoxic and exhibited reduced or no cytotoxicity toward melanoma cells. Moreover, technological validation of the most potent AFiv 50EtOH extract within model O/W and W/O emulsions demonstrated exceptional 30-day physicochemical stability and compatibility