Table 1.

Linearity and sensitivity of UPLC-MS/MS assay for standards in fermented DBT

Analyte	Calibration curve	R2a	Linear range (μg/mL)	LLOQ (μg/mL)	LOD (μg/mL)
Cal-O-β-glud	y = 0.1032x + 0.0397	0.9986	0.023–50	0.023	0.008
Ononin	y = 0.2496x + 0.1498	0.9967	0.023–50	0.023	0.008
Calycosin	y = 4.4401x + 4.0138	0.9909	0.023–50	0.023	0.008
Formononetin	y = 3.8437x + 3.2295	0.9923	0.023–50	0.023	0.008

^aThe calibration curve was constructed by plotting the peak area versus the concentration of each analyte. Each calibration curve was derived from 6 data points, n = 3. R², coefficient of determination

LLOQ lower limit of quantification

LOD limit of detection

Cal-O-β-glu^d calycosin-7-O-β-D-glucoside