Table 3 System review results of pu-erh’s inhibition effects on alpha amylase

Zhang et al.¹⁵

Alpha amylase inhibition assay

Alfa-amylase inhibition of raw materials increased with the extension of fermentation time, the inhibition rate dropped, and reached the lowest in mid stage fermentation, while in late fermentation, inhibition increased and αamylase inhibition of product tea was stronger.

Zhang et al.¹⁶

Alpha amylase inhibition assay

The results showed that the best inhibition rate is 32.68% in water temperature of 90 °C, pu-erh tea/water ratio of 1:20, and extraction time lasting 1 h.

Zhang et al.¹⁷

Alpha amylase inhibition assay

The result showed that Gallic acid had a strong inhibition on alpha amylase, with inhibition rate of 63.76%.

Du et al.⁴

Alpha glucosidase inhibition assays for the WEPT were conducted using rat small intestinal sucrose and maltase in vitro

WEPT showed inhibitory effects on rat intestinal sucrose, maltase, and porcine pancreatic amylase, as shown in Table 3, but are less potent compared to acarbose (IC₅₀= 4.35 ± 0.59, 6.63 ± 0.70, and 64.19 ± 6.77 μmol/L for sucrose, maltase, and amylase, respectively).

Zhou et al¹⁸

Alpha amylase inhibition assay

1. Prolonged storage years will increase inhibition effect on alpha amylase activity.

2. The inhibition rate ranges from 10 to 22%. The regression model: y (alphaamylase inhibition rate) = −31.43 + 0.748x; X: theabrownin, TB; R² = 97.4%.

Liu and Huang¹⁹

Alpha amylase inhibition assay

1. Pu-erh has inhibition effects on alpha amylase.

2. Regression equation: y = 0.0008x3 + 0.0075x2–0.0106x+ 0.1236, X: extracted tea concentration; R² = 0. 998.

Wu et al.²⁰

Alpha amylase inhibition assay

Optimal temperature of alpha amylase inhibitor acting is 70 °C, and suppression ratio of alpha Amylase inhibitor in these teas is Ilex >aged pu-erh tea >extra-strong tea >dragon well tea >fresh pu-erh tea.