Evidence-Based Complementary and Alternative Medicine

Research Article

Berry and Citrus Phenolic Compounds Inhibit Dipeptidyl Peptidase IV: Implications in Diabetes Management

Table 2

Anthocyanin (ANC) concentration (μM) from blueberry-blackberry wine blends needed to inhibit DPP-IV enzyme activity by 50%^1,2.


Blend ratio (% blueberry : % blackberry)	Fraction	IC₅₀(μM)

100% Blueberry	ANC1	>300
	ANC2	4.67 ± 0.63^a
	ANC3	0.64 ± 0.33^bc
	ANC4	1.37 ± 0.58^abc
	ANC5	0.72 ± 0.25^bc

75% : 25%	ANC1	NA³
	ANC2	2.02 ± 0.56^ab
	ANC3	0.41 ± 0.11^c
	ANC4	0.22 ± 0.05^c
	ANC5	0.36 ± 0.16^c

25% : 75%	ANC1	NA
	ANC2	0.34 ± 0.10^c
	ANC3	0.33 ± 0.08^c
	ANC4	0.52 ± 0.18^c
	ANC5	0.20 ± 0.10^c

100% Blackberry	ANC1	NA
	ANC2	0.22 ± 0.03^c
	ANC3	0.07 ± 0.02^c
	ANC4	0.18 ± 0.07^c
	ANC5	0.20 ± 0.09^c

¹IC₅₀ values were determined from at least two independent duplicates done in triplicate and calculated in C3G equivalents. Values are means ± SEM. Means with different letters are significantly different ().
²The positive control of inhibition for DPP-IV was diprotin A (Ile-Pro-Ile) with an IC₅₀ value of 4.21 ± 2.01 M.
³NA: No activity detected at >300 M.