Uv mini uv vis spectrophotometer

Extract testing began with a 500 µL extraction of a mixture containing the extract and 5% sodium nitrate (w/v), followed by observation of the resulting solution and then the addition of 10% AlCl₃ (w/v) (300 µL) from samples (cell suspension and callus) [91 ]. Following five minutes of room-temperature incubation, NaOH (1 mL, 1M) was inserted to stop the reaction. The entire amount of flavonoid was calculated using 510 nm spectroscopy (Shimadzu UV mini-UV–VIS spectrophotometer), and the amount was computed using a standard curve of quercetin with concentrations of 1–100 mg (100 g⁻¹ per DW).

The TPC (in the callus or cell suspension) was identified after 12 h of methanol extraction [74 (link)] with shaking and subsequent anhydrous Na₂SO₄ drying. The test solution (10 µL) and Folin–Ciocalteu solution (50 µL) were applied to 790 µL of distilled water [91 ]. The mixture underwent a vortex to break up any large particles, 150 µL of 20% Na₂CO₃ (w/v) was added for 1 min, and then the mixture was left to incubate at 25 °C for 120 min (in the dark). Phenolic acid was measured at 750 nm using a Shimadzu UV mini-UV–VIS spectrophotometer (Shimadzu Corporation, Kyoto, Japan) with an approximation made from a gallic acid reference curve.