Association between microbial community composition and quality indicators of strong-flavor Daqu of different producing regions in China

Figures & data

Figure 1. Appearance of Daqu samples from different geographical origins. a) Strong-flavor Daqu (SFD) from Yi-Bin city (YB), b) SFD from Lu-Zhou city (LZ), c) SFD from Ji-Ning city (JN), d) SFD from Bo-Zhou city (BZ), e) SFD from Fu-Yang city (FY), f) SFD from Lin-Quan city (LQ).

Figure 2. Schematic representation of sampling positions in Daqu.

Table 1. Alpha diversity indices of fungal metagenomes of Strong-flavor Daqu samples from different geographical locations in China.

Sample	Coverage	Shannon	Simpson	Ace	Chaol
LZS	0.999	2.473	0.656	321.534	308.55
YBS	1.000	2.944	0.717	215.176	216.6
JNS	0.999	4.21	0.909	340.98	332.596
BZS	0.999	3.977	0.882	387.798	381.552
FYS	0.999	2.389	0.594	279.603	266.684
LQS	0.999	2.214	0.641	261.29	262.935
LZI	1.000	1.187	0.251	213.443	205.098
YBI	0.999	2.448	0.654	286.411	278.565
JNI	0.999	2.039	0.496	338.401	332.52
BZI	0.999	2.55	0.721	255.03	248
FYI	0.999	1.951	0.603	292.64	287.838
LQI	1.000	3.346	0.82	255.354	252.667

Table 2. Alpha diversity indices of bacterial metagenomes of Strong-flavor Daqu samples from different geographical locations in China.

Sample	Coverage	Shannon	Simpson	Ace	Chaol
LZS	0.999	2.713	0.708	253.025	246.000
YBS	0.999	4.577	0.892	355.604	358.091
JNS	1.000	4.550	0.905	249.508	247.207
BZS	0.999	4.504	0.8919	284.794	285.433
FYS	0.999	4.119	0.859	398.131	397.791
LQS	0.999	2.278	0.890	334.002	330.878
LZI	1.000	2.719	0.790	103.797	101.400
YBI	1.000	2.456	0.513	201.899	194.375
JNI	0.999	2.937	0.615	314.725	306.918
BZI	0.999	2.952	0.753	282.839	276.067
FYI	0.999	3.911	0.822	364.086	358.400
LQI	0.999	3.050	0.620	335.3102	335.559

Figure 3. Histogram of relative abundance at phylum level of microorganisms found in Daqu. a) Fungal phyla across the surface (S) and central (I) parts of Daqu samples, b) Fungal phyla across different Daqu samples, c) Bacterial phyla across S and I parts of Daqu, d) Bacterial phyla across different Daqu samples.

Figure 4. Histogram of relative abundance at genus level of microorganisms found in Daqu. a) Fungal genera across the surface (S) and central (I) parts of Daqu samples, b) Fungal genera across different Daqu samples, c) Bacterial genera across S and I parts of Daqu samples, d) Bacterial genera across different Daqu samples.

Figure 5. Inter group T-test at genus level of microorganisms found in Daqu samples. a) Fungi, b) Bacteria. Each bar in represents the mean of species with significant differences in abundance between sample groups (surface part of Daqu, S, central part of Daqu, I). The leftmost endpoint of each circle represents the mean difference of the lower limit of the 95% confidence interval, the rightmost end of the circle represents the upper limit of the 95% confidence interval of the mean difference, the center of the circle represents the difference between means, the group represented by the color of the circle is the group with the highest mean, and the far right end of the displayed result is the corresponding difference between p values for species.

Figure 6. Principal coordinate analysis (PCoA) of microbial communities based on weighted UniFrac distances. a) Fungi, b) Bacteria. Data points are colored by sample type.

Table 3. Quality indicator parameters of Strong-flavor Daqu samples from different geographical locations in China.

Sample	Moisture (g/100 g)	Acidity (mmol/10 g)	Starch (g/100 g)	Reducing sugar (g/100 g)	Fermentation ability (g CO2/0.5 g ·72 h)	Saccharification ability (mg/g h)	Esterification ability (mg/g·72 h)
JNI	12.10 ± 0.10	1.00 ± 0.01	57.12 ± 2.34	1.75 ± 0.34	0.13 ± 0.01	120.00 ± 13.14	12.00 ± 2.41
JNS	11.70 ± 0.12	0.50 ± 0.05	58.93 ± 1.74	1.30 ± 0.23	0.09 ± 0.01	972.00 ± 10.33	6.00 ± 3.44
LQI	12.00 ± 0.23	1.00 ± 0.03	58.93 ± 2.21	1.65 ± 0.11	0.17 ± 0.01	282.00 ± 12.31	9.00 ± 2.12
LQS	11.00 ± 0.22	0.60 ± 0.09	59.56 ± 2.03	1.38 ± 0.19	0.12 ± 0.02	918.00 ± 11.46	7.00 ± 1.29
LZI	12.30 ± 0.18	0.70 ± 0.02	58.93 ± 1.09	1.28 ± 0.09	0.07 ± 0.00	354.00 ± 10.34	11.00 ± 2.02
LZS	12.10 ± 0.19	0.50 ± 0.02	59.88 ± 1.34	1.25 ± 0.10	0.07 ± 0.00	798.00 ± 14.12	6.00 ± 1.47
BZI	16.20 ± 0.16	0.60 ± 0.01	56.97 ± 2.34	1.25 ± 0.13	0.22 ± 0.02	130.00 ± 18.34	13.00 ± 1.76
BZS	11.70 ± 0.24	0.50 ± 0.07	58.93 ± 2.41	1.15 ± 0.15	0.08 ± 0.01	546.00 ± 21.38	10.00 ± 2.47
YBI	14.20 ± 0.31	0.80 ± 0.03	60.2 ± 3.04	1.25 ± 0.15	0.11 ± 0.02	111.00 ± 10.93	12.00 ± 1.06
YBS	11.40 ± 0.20	0.70 ± 0.04	60.86 ± 3.33	1.1 ± 0.19	0.04 ± 0.01	810.00 ± 11.16	7.00 ± 2.03
FYI	14.70 ± 0.14	0.80 ± 0.02	58.93 ± 1.29	1.25 ± 0.23	0.21 ± 0.01	156.00 ± 13.31	12.00 ± 2.47
FYS	10.50 ± 0.11	0.70 ± 0.01	59.24 ± 1.59	1.20 ± 0.25	0.04 ± 0.01	810.00 ± 32.23	3.00 ± 1.04

Figure 7. Spearman correlation analysis of genus-level microbial community structure and physicochemical parameters. a) Fungi, b) Bacteria. Environmental factor information is given vertically, species information is given horizontally. Values in the middle of the heat map are Spearman correlation coefficients (r), which are between −1 and 1, r < 0 indicates a negative correlation, r > 0 indicates a positive correlation, * indicates p values < .05, ** indicates p values < .01. M: moisture content, A: acidity, S1: starch, Rs: reducing sugar content, Fa: fermentation power, Sa: saccharification ability, Ea: esterification ability.