Effect of ultrasound‐assisted extraction on phenolic profile, bio‐accessibility, OVCAR‐3, and SKOV‐3 cytotoxicity in blackthorn ( <i>Prunus spinosa</i> L.)

This study aimed to examine the extraction of specific phenolic compounds from blackthorn using ultrasound-assisted extraction (UAE) and to evaluate the influence of UAE on the phenolic composition, bioaccessibility, and cytotoxic effect evaluated on ovarian cancer (OVCAR-3 and SKOV-3) and healthy (HaCaT) cell lines. The UAE parameters were optimized by modeling with the response surface method. Temperature, time, and ultrasound amplitude were utilized to determine the optimal extraction conditions. Optimization experiments were conducted to assess the influence of independent variables on the maximum concentrations of six phenolic compounds identified via high-performance liquid chromatography (HPLC) and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. The optimal conditions for UAE were determined as an extraction temperature of 33.177°C, a duration of 4.334 min, and an amplitude of 38.980%. The phenolic profile of the extract obtained under optimized UAE conditions (B-UAE_opt) was re-examined, confirming that it remained consistent at the individual component level. Using an in vitro digestion model, UAE was found to increase the bioaccessibility of antioxidant activity in the small intestine. The IC₅₀ values for OVCAR-3 were 64 and 67 mg mL^-1 for blackthorn and B-UAE_opt, while the IC₅₀ values for SKOV-3 were 53 mg mL^-1 and 50 mg mL^-1 for blackthorn and B-UAE_opt, respectively. This study showed that UAE is an exceptionally effective method for extracting phenolic compounds from blackthorn, as it preserves the phenolic profile, enhances bioaccessibility, and maintains cytotoxic effects without any detrimental impact.