Extraction Time Modulates Ginger Phytochemicals and Selective Cytotoxicity in Hormone Receptor-Positive Breast Cancer Cells

Introduction: Ginger (Zingiber officinale Roscoe) contains bioactive phytochemicals with potential anticancer properties; however, the influence of hot‑water reflux extraction time on phytochemical composition and selective cytotoxicity against hormone receptor‑positive breast cancer cells remains unclear. Methods: Ginger powder was extracted by hot‑water reflux at 98-100 °C for 30, 60, 90, and 120 minutes (GS‑30, GS‑60, GS‑90, and GS‑120). Concentrations of [6]‑gingerol and [6]‑shogaol were determined using high‑performance liquid chromatography with ultraviolet detection (HPLC‑UV). Cytotoxicity against MCF‑7 breast cancer cells and normal human dermal fibroblasts (NHDF) was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The half-maximal inhibitory concentration (IC50), half-maximal cytotoxic concentration (CC50), and the selectivity index (SI) were calculated. Results: Increasing the extraction time resulted in progressively higher concentrations of both [6]‑gingerol and [6]‑shogaol, with GS-120 containing the highest levels of these marker compounds. However, GS-30 and GS-60 exhibited greater cytotoxicity toward MCF-7 cells, with IC50 values of 112.47 ± 6.03 μg/mL and 112.93 ± 5.52 μg/mL, respectively, compared with 323.13 ± 42.99 μg/mL for GS-90 and 404.07 ± 14.86 μg/mL for GS-120. The SI values were 7.5, 8.6, 2.27, and 2.03 for GS-30, GS-60, GS-90, and GS-120, respectively, with GS-60 exhibiting the greatest selectivity toward breast cancer cells over normal fibroblasts. Conclusions: Although prolonged extraction increased the concentrations of [6]-gingerol and [6]-shogaol, it did not enhance selective anticancer activity. These findings suggest that the selective cytotoxic effects of hot-water ginger extracts are influenced by the overall phytochemical profile rather than the abundance of individual marker compounds. Integrating phytochemical characterization with biological evaluation may facilitate the optimization of extraction conditions for developing ginger extracts with improved selective anticancer activity.