Table 4 Short-chain fatty acids (SCFA) in the caecal digesta of rats consuming control (C) and inulin (IN) diets without or with the addition of grapefruit flavonoid extract (GFE)

C

IN

C + GFE

IN + GFE

IN

GFE

IN × GFE

Concentration (μmol/g)

   Acetic acid

31.7

31.9

17.6

21.0

1.359

NS

< 0.001

NS

   Propionic acid

3.59^b

4.81^a

2.44^c

3.39^b

0.185

< 0.001

< 0.001

NS

   Iso-butyric acid

0.944

0.686

0.569

0.580

0.044

NS

< 0.01

NS

   Butyric acid

4.66^b

8.11^a

1.42^c

1.81^c

0.524

< 0.001

< 0.001

< 0.001

   Iso-valeric acid

1.12^a

0.803^b

0.766^b

0.706^b

0.048

< 0.05

< 0.01

NS

   Valeric acid

1.400

1.082

0.892

0.821

0.063

NS

< 0.001

NS

   Total SCFA

43.4

47.4

23.6

28.3

2.020

NS

< 0.001

NS

Profile (% of total)

   Acetic acid

72·9^a

67·3^b

74·2^a

74·1^a

0·699

< 0·01

< 0·001

< 0·01

   Propionic acid

8·3^b

10·3^a

10·4^a

12·1^a

0·389

< 0·01

< 0·01

NS

   Butyric acid

10·8^b

17·0^a

6·0^c

6·3^c

0·872

< 0·001

< 0·001

< 0·001