Insight into isolation and elucidation of cytotoxic ergostanoids from the mushroom Sarcosphaera crassa (Santi) Pouzar: An edible mushroom

Abstract

Sarcosphaera crassa is a mushroom consumed in Europe and Anatolia after being cooked well. The cytotoxic activity of the extracts of unbaked S. crassa against MCF7, HT29, HeLa cancer cell lines and toxicity against PDF fibroblast healthy cell lines were studied using MTT assay. Acetone and methanol extracts of the mushroom exhibited significant cytotoxic activity. Further investigation of cytotoxic extracts afforded two new fatty acid sterols (1-2), a new ergosterol glycoside (4), and seven known compounds, including a fatty acid sterol (3), a steroid glycoside (5), two ergostanoids (6-7) and three sugars (8-10). These compounds were identified as brassicasteryl heptadecanoate (1), brassicasteryl palmitoleate (2), brassicasteryl linoleate (3), brassicasterol β-ᴅ-xylofuranoside (4), brassicasterol β-ᴅ-glucoside (5), brassicasterol (6), ergosterol-endoperoxide (7), mannitol (8), erythritol (9) and turanose (10). Among them, 7 exhibited a moderate cytotoxic activity against HeLa (IC₅₀: 70.1 ± 2.0 µg/mL) and high activity against HT29 (IC₅₀: 38.8 ± 0.9 µg/mL), and MCF7 (IC₅₀: 62.9 ± 1.3 µg/mL) cancer cell lines. Compounds 4, 5, and 6 also exhibited significant cytotoxic activity against HT29 and MCF7. Moreover, all compounds exhibited weak toxicity against PDF healthy cell lines. This study indicates the potential use of Sarcosphaera crassa as a natural source of cytotoxic ergostanoids, which can be considered a dietary supplement for cancer prevention.

Keywords: Cytotoxic Activity; Isolation and Structural Elucidation; Mycochemistry; Poisonous mushroom; Sarcosphaera crassa (Santi) Pouzar; Spectroscopic Techniques.