Fig. 3. (a) Characterization of herbs and herbal foods upon baking: PL activity test of RP Tai, Lycium chinense, Zingiber officinale, and Allum schoenoprasum with NBT/BCIP substrate at pH 13 (NBT/BCIP concentration: 0.15 mg mL⁻¹, herb concentration: 2.5 mg mL⁻¹). S represents substrate. (b) Phosphatase inhibition tests by Ca²⁺ and EDTA with NBT/BCIP substrate; left panel: inhibition tests by Ca²⁺ against RP; middle panel: inhibition tests by Ca²⁺ against ALP; right panel: inhibition tests by EDTA against RP. * = significant difference with p < 0.05; ** = significant difference with p < 0.01.