Glutamate glotm assay

Intracellular metabolites were measured using Glucose-Glo^TM Assay, Lactate-Glo^TM Assay, and Glutamate-Glo^TM Assay (Promega) according to the manufacturer’s protocol.

The SK-MEL-28, RPMI-7951, and SK-MEL-5 cells (2.5 × 10⁴/mL) were seeded in a 96-well plate and cultured at 37 °C in a 5% CO₂ incubator for 24 h. Then the cells were treated with PBS or ScF at concentrations of 50, 100, and 200 µg/mL for 48 h. The culture medium was collected and used to determine the level of lactate production by the Lactate-Glo^TM Assay (Promega, Fitchburg, WI, USA) according to the manufacturer’s protocol. The cells remaining attached were washed twice with PBS and used to determine the level of glutamate production by the Glutamate-Glo^TM Assay (Promega, Fitchburg, WI, USA) according to the manufacturer’s protocol. The level of lactate and glutamate content was determined by the luminescence method on a PHERAstar FS multi-mode microplate reader (BMG Labtech, Offenburg, Germany) using the appropriate calibration curves.