Compound Standard curve
verbascoside y = 4.90599x - 1.97683; R² = 0.9999
apigenin-7-O-glucuronopyranosyl-(1→2)-glucuronopyranoside y = 6.89810x - 19.60755; R² = 0.9997
7-hydroxytomentoside y = 4.02230x - 1.07988; R² = 0.9995
catalpol y = -41.329553x2 + 17210.064761x + 12019.481295; R² = 0.9972