Mycochemical Profiling, Radical Scavenging, and Cytotoxic Evaluation of Pleurotus djamor var. roseus Extract in ER-Positive Breast Cancer Cells

Abstract

Background Edible mushrooms such as Pleurotus djamor var. roseus have been reported to contain bioactive metabolites with antioxidant and cytotoxic activity, but evidence in estrogen receptor-positive (ER+) breast cancer models remains limited. This study characterized the mycochemical profile of a methanolic P. djamor var. roseus extract and evaluated its antioxidant and cytotoxic activity, hypothesizing a measurable, dose-dependent reduction in ER+ MCF-7 breast cancer cell viability. Methods Gas chromatography–mass spectrometry (GC–MS) was used for mycochemical profiling. Antioxidant capacity was assessed by DPPH radical-scavenging and total phenolic content (TPC) assays. Cytotoxicity was evaluated by MTT assay in MCF-7 cells after 24 h exposure to extract concentrations of 25–400 μg/mL, with doxorubicin (1 μg/mL) as a positive control. Data were analyzed by one-way ANOVA with Tukey’s post hoc test; a two-way ANOVA (treatment × concentration) was additionally applied to the DPPH data. Results GC–MS tentatively identified fatty acids, phenolic derivatives, and quinoline-related compounds. The extract showed dose-dependent radical-scavenging activity (81.01–97.18% inhibition across 0.1–0.7 mg/mL) and a phenolic content of 3.24 ± 0.04 mg GAE/g dry weight, though the tested concentration range did not allow accurate IC 50 estimation. In MCF-7 cells, the extract produced a concentration-dependent reduction in viability, with an IC 50 of 67.28 μg/mL (R 2  = 0.989); viability fell to approximately 4% of control at 400 μg/mL. Morphological changes consistent with cytotoxic stress were observed. Conclusions The methanolic extract of P. djamor var. roseus shows reproducible, dose-dependent cytotoxic activity against ER+ MCF-7 breast cancer cells and warrants further investigation into its mechanisms and molecular targets.