Gastrointestinal digestion fate of Tremella fuciformis polysaccharide and its effect on intestinal flora: an in vitro digestion and fecal fermentation study

Figures (6) Tables (2)

Figure 1.
Flow diagram of (a) in vitro digestion and (b) fecal fermentation method of TFP.
Figure 2.
Variations in structural characterizations of TFP during in vitro digestion. (a) Monosaccharide composition. (b) FT-IR. (c) Congo red staining. (d) Thermogravimetric curve. (e) Rheological properties. (f) Particle size and zeta potential.
Figure 3.
Variations in C_R, pH, residual carbohydrates and gas production during in vitro fermentation of TFP. (a) Total carbohydrates. (b) Reducing sugars. (c) pH value. (d) The amount of gas produced.
Figure 4.
Correlation curve of species diversity and between-group similarity analysis of gut microflora in vitro fermentation for 48 h. (a) Rank-Abundance curve. (b), (c) Rarefaction curve. (d), (e) Hierarchical clustering tree based on OUT and Genus levels. (f) ANOSIM/Adonis analysis. (g) PLS-DA analysis.
Figure 5.
Analysis of α and β diversity after 48 h of fermentation in vitro in the gut microbial community. (a)-(d) α diversity indices. (e) PCA analysis. (f) PCoA analysis. (g) NMDS analysis.
Figure 6.
Analysis of gut microbial community composition during 48 h of in vitro fermentation. (a), (b) Relative abundance. (c), (d) Community heatmap analysis. (e), (f) Kruskal-Wallis H test bar plot.

	TFP	TFP-S	TFP-G	TFP-I
Total polysaccharides (%)	89.62 ± 0.82^a	88.90 ± 0.55^ab	87.28 ± 0.78^b	86.07 ± 1.03^c
Total uronic acids (%)	15.35 ± 0.80^a	15.83 ± 0.36^a	14.74 ± 0.11^b	14.15 ± 0.33^c
Total proteins (%)	2.53 ± 0.05^a	1.90 ± 0.01^b	0.79 ± 0.01^c	0.60 ± 0.02^d
Molecular weight
Mw × 10⁴ (Da)	2.0361 ± 0.0375^a	1.9686 ± 0.0412^a	1.7864 ± 0.0109^b	1.6620 ± 0.0156^c
Mw/Mn	1.33172	1.2779	1.20094	1.36855
Constituent monosaccharides and molar ratios
Man	1.00	1.00	1.00	1.00
GlcA	0.07	0.08	0.08	0.07
Glc	0.86	0.73	0.75	0.58
Xyl	0.42	0.44	0.40	0.41
Fuc	0.19	0.19	0.20	0.20

Table 1.

Data summarization of TFP, TFP-S, TFP-G and TFP-I.

Processes	Time (h)	C_R (mg·mL⁻¹)
Origin	−	0.115 ± 0.001^a
Saliva digestion stage	0.25	0.113 ± 0.003^a
	0.5	0.114 ± 0.002^a
	1	0.116 ± 0.001^a
Gastric juice digestion stage	0.5	0.312 ± 0.032^e
	1	0.364 ± 0.002^d
	2	0.408 ± 0.010^c
	4	0.583 ± 0.023^b
	6	0.729 ± 0.016^a
Small intestinal juice digestion stage	0.5	0.809 ± 0.011^c
	1	0.836 ± 0.024^bc
	2	0.880 ± 0.039^b
	4	0.931 ± 0.022^ab
	6	0.950 ± 0.005^a

Table 2.

Variations in C_R of TFP during in vitro digestion.