Table 1.

Increase (Δ) in short-chain fatty acids (SCFAs) (mmol L⁻¹) (acetate, propionate, butyrate and total) produced by human faecal microbiota after 6, 24 and 48 h of in vitro fermentation with different substrates: RAS (whole raspberry), PEX (polyphenol extract), TDF (total dietary fibre) and IDF (insoluble dietary fibre). The faecal samples were obtained from NW (normal-weight) and OW (overweight) volunteers

	RAS			PEX			TDF			IDF
	6 h	24 h	48 h	6 h	24 h	48 h	6 h	24 h	48 h	6 h	24 h	48 h
NW
Acetate	12.5 ± 1.6a	15.9 ± 5.3a	14.5 ± 5.5 a	6.4 ± 1.3*b	9.0 ± 6.3 ab	13.3 ± 2.4ab	4.6 ± 0.9b	9.4 ± 2.6 ab	9.3 ± 4.4ab	4.1 ± 1.1b	6.4 ± 0.6 b	6.8 ± 0.9*b
Propionate	3.1 ± 0.7*a	3.7 ± 0.7 a	3.6 ± 0.5 a	1.3 ± 0.1*b	1.9 ± 1.0 b	2.7 ± 0.6 ab	1.0 ± 0.4b	1.8 ± 1.2 b	1.9 ± 1.1 b	1.0 ± 0.4b	1.4 ± 0.5 b	1.6 ± 0.7b
Butyrate	1.7 ± 0.2	2.5 ± 0.4 a	2.6 ± 1.0	1.4 ± 0.5	2.1 ± 1.1 ab	2.8 ± 0.2	1.5 ± 0.6	1.9 ± 0.5 ab	2.1 ± 0.6	1.4 ± 0.1	1.7 ± 0.5 b	1.9 ± 0.6
Total	17.3 ± 1.3a	22.0 ± 5.8	20.6 ± 6.7 a	9.1 ± 1.9*b	12.9 ± 8.4	18.8 ± 1.9ab	7.1 ± 1.2b	13.1 ± 4.0	13.2 ± 5.6ab	6.6 ± 1.4b	9.5 ± 0.4	10.4 ± 1.8b
OW
Acetate	9.9 ± 5.5 ab	22.2 ± 5.9a	22.1 ± 9.1	15.0 ± 2.6*a	21.1 ± 7.6a	20.4 ± 10.6	5.0 ± 0.4b	9.1 ± 2.1 b	9.3 ± 1.4	4.1 ± 2.0b	8.3 ± 2.7 b	9.0 ± 0.1*
Propionate	0.9 ± 0.9*ab	3.6 ± 1.2 a	3.9 ± 2.2	1.7 ± 0.3*a	3.5 ± 1.5 a	3.6 ± 2.4	0.7 ± 0.2 b	1.5 ± 0.5 b	1.6 ± 0.4	0.7 ± 0.4 b	1.2 ± 0.5 b	1.6 ± 0.6
Butyrate	0.9 ± 1.0 b	2.4 ± 0.8 ab	2.5 ± 0.8	2.3 ± 0.2a	3.0 ± 0.7 a	2.9 ± 0.6	1.5 ± 0.2ab	1.8 ± 0.3 b	1.9 ± 0.4	1.0 ± 0.4ab	1.9 ± 0.3 b	1.9 ± 0.5
Total	11.7 ± 7.2ab	28.2 ± 7.8a	28.5 ± 12.0	19.0 ± 3.1*a	27.6 ± 9.7a	26.9 ± 13.5	7.2 ± 0.5b	12.4 ± 2.6ab	12.8 ± 1.6	5.8 ± 2.5b	11.3 ± 2.8b	12.4 ± 0.3

Values are expressed as the means ± SD (n = 3). Different letters (a–c) indicate significant differences (p < 0.05) among the fractions at the same time. *Indicates significant differences (p < 0.05) between normal-weight and overweight volunteers