In vitro gastrointestinal digestion of a bisdemethoxycurcumin-rich Curcuma longa extract and its oral bioavailability in rats

Bulletin of the National Research Centre

Table 1 Antioxidant activities of the turmeric extracts before and after gastrointestinal digestion

Digestive phase	Standardized C. longa extract	Regular turmeric extract	p value^#
DPPH radical scavenging (%)
Undigested	5.77 ± 1.21	10.65 ± 0.71	0.004**
Gastric	27.33 ± 0.46	28.43 ± 1.55	0.304
Intestinal	9.31 ± 1.07	11.96 ± 1.91	0.104

Digestive phase	Standardized C. longa extract	Regular turmeric extract	p value*
ABTS cation scavenging (%)
Undigested	25.71 ± 1.37	23.69 ± 2.47	0.283
Gastric	15.29 ± 1.87	14.43 ± 0.60	0.492
Intestinal	67.36 ± 2.20	61.58 ± 1.36	0.018*
Nitric oxide scavenging (%)
Undigested	62.20 ± 5.98	25.89 ± 3.4	< 0.001***
Gastric	49.11 ± 3.82	64.01 ± 4.38	0.011*
Intestinal	45.55 ± 3.86	18.86 ± 5.24	0.002**
Superoxide radical scavenging (%)
Undigested	36.98 ± 0.83	24.35 ± 0.62	< 0.001***
Gastric	86.47 ± 2.14	87.28 ± 0.91	0.576
Intestinal	72.58 ± 0.85	68.94 ± 2.17	0.054

The values are presented as mean ± standard deviation of three independent experiments. ^#Independent t test. *p < 0.05; **p < 0.01; ***p < 0.001