Interaction Between Lactic Acid Bacteria and Acetic Acid Bacteria in Sichuan Bran Vinegar: Impact on Their Growth and Metabolites
by
Jianlong Li
1,2,†, 
Jie Wu
1,†,
Meiling Tu
1,
Xue Xiao
2,
Kaidi Hu
1,2,
Qin Li
1,2,
Ning Zhao
1,2,
Aiping Liu
1,2,*,
Xiaolin Ao
1,2,
Xinjie Hu
1,2 and
Shuliang Liu
1,2,* 1
College of Food Science, Sichuan Agricultural University, Ya’an 625014, China
2
Key Laboratory of Agricultural Product Processing, Nutrition Health (Co-Construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Ya’an 625014, China
*
Authors to whom correspondence should be addressed.
†
These authors contributed equally to this work.
Foods 2025, 14(9), 1471; https://doi.org/10.3390/foods14091471
Submission received: 28 March 2025
/
Revised: 18 April 2025
/
Accepted: 22 April 2025
/
Published: 23 April 2025
(This article belongs to the Special Issue Traditional Fermented Food: Physicochemical, Sensory, Flavor, and Microbial Characteristics)
Abstract
:Microbial interactions are essential for maintaining the stability and functionality of microbiota in fermented foods. In this study, representative strains of predominant lactic acid bacteria and acetic acid bacteria in Sichuan bran vinegar were selected, and their interactions in a simulated solid-state fermentation system were investigated. The results reveal that the biomass of A. pasteurianus LA10 significantly increased in both the co-culture and the pure culture, whereas the biomass of L. amylovorus LL34 in the co-culture (6.44 ± 0.30 lg CFU/g) was significantly lower than that in the pure culture (7.28 ± 0.30 lg CFU/g) (p < 0.05), indicating a partially harmful symbiosis between these two strains. The metabolic analysis shows that total acid (21.82 mg/g) and acetic acid (9.53 mg/g) contents in the co-culture were lower than those in the pure culture of LA10, suggesting that LL34 inhibited the acid-producing activity of LA10 to some extent. The interaction between the two bacteria also influenced the production of volatile compounds and non-volatile compounds, as revealed by GC-MS and untargeted UHPLC-MS/MS, respectively. Significant enrichment of acid and amino acid metabolism pathways was observed in the co-culture, revealing the impact of bacterial interactions on flavor development. This study provides valuable insights into the advancement of vinegar brewing technology.
1. Introduction
Cereal vinegar is a vital acidic condiment in the daily Chinese diet, with a history spanning over 3000 years [1,2]. Various types of vinegar have been developed, particularly Sichuan Baoning vinegar, Zhenjiang aromatic vinegar, Shanxi aged vinegar, and Fujian Monascus vinegar [3]. Traditional production involves solid-state fermentation; however, a more efficient approach involving liquid-state fermentation followed by solid-state fermentation is now preferred [4]. Sichuan Baoning vinegar is a representative Sichuan bran vinegar that distinguishes itself from other vinegar due to its whole process of traditional solid-state fermentation using uncooked wheat bran as the primary raw material. This vinegar undergoes saccharification, alcohol fermentation, and acetic acid fermentation simultaneously in a single fermentation pond, with Daqu (also called great koji, a traditional fermentation starter made from a blend of grains that have been moistened and allowed to ferment for several days) incorporated with Chinese herbs serving as a saccharifying agent [5].
Lactic acid and acetic acid are the predominant organic acids in solid-state vinegar fermentation, comprising over 90% of the total organic acid content [6,7,8]. Lactic acid is characterized by its mildness, while acetic acid imparts a more pungent flavor. The acid ratio plays a crucial role in determining the sensory characteristics of vinegar [9]. Sichuan bran vinegar is notable for its higher lactic acid content than acetic acid [10,11]. As is known, the microbial composition of vinegar is complex, with microbial interactions essential for its stability and functionality. The dominant bacteria in the solid-state fermentation of vinegar differ at different periods, such as mold in the early stage of fermentation (starch saccharification fermentation), yeast in the middle stage (alcohol fermentation), and acetic acid bacteria in the late stage (acetic acid fermentation). At the same time, there are other dominant bacteria, such as Lactobacillus, Bacillus, Stenotrophomonas, Methyloversatilis, and Amycolatopsis, etc., among which lactic acid can produce lactic acid to neutralize the irritation of acetic acid [12]. Bacillus can secrete a variety of hydrolases that play an important role in liquefaction and saccharification and can produce organic acids through the tricarboxylic acid cycle [13]. However, a comprehensive understanding of these interactions in vinegar remains limited [14]. Lactic acid and acetic acid are key metabolites produced by lactic acid bacteria and acetic acid bacteria, respectively. Metagenomic sequencing revealed Lactobacillus amylovorus (L. amylovorus) and Acetobacter pasteurianus (A. pasteurianus) as dominant strains in Cupei (the mixture of ingredients used for cereal vinegar fermentation) during Sichuan Baoning vinegar fermentation [15].
In this study, L. amylovorus LL34 and A. pasteurianus LA10 [16], isolated from Sichuan Baoning vinegar for their high lactic acid and acetic acid yields and robust growth capacities, were employed as representative strains. This study aimed to investigate the interaction between these two strains during fermentation using a simulated fermentation system and its impact on strain growth, acid production, and volatile and non-volatile compounds. This study offers insights into microbial interactions during fermentation and provides theoretical guidance for enhancing the quality of Sichuan bran vinegar.
2. Materials and Methods
2.1. Strains and Growth Conditions
L. amylovorus LL34 and A. pasteurianus LA10, isolated from Cupei of Sichuan Baoning vinegar, were maintained at the Laboratory of Microbiology, College of Food Science, Sichuan Agricultural University. The strains were individually cultured in 5 mL of MRS broth (10 g peptone, 8 g beef extract, 4 g yeast extract, 20 g glucose, 2 g K2HPO4, 5 g CH3COONa, 2 g ammonium citrate, 0.2 g MgSO4·7H2O, 0.05 g MnSO4·H2O, 1 mL Tween 80, pH 6.2–6.5, and 1 L H2O; L. amylovorus LL34) and 5 mL of GYE broth (1% glucose, 1% yeast extract, and 3% ethanol; A. pasteurianus LA10). L. amylovorus LL34 was statically incubated at 37 °C for 24 h, while A. pasteurianus LA10 was cultured in a shaking incubator at 30 °C for 72 h at 160 rpm.
2.2. Interaction Between Lactic Acid Bacteria and Acetic Acid Bacteria
2.2.1. Solid-State Fermentation and Sampling
A Cupei stimulation medium comprising wheat bran (30%), wheat flour (20%), and MRS broth (50%) was developed for solid-state fermentation. The medium was sterilized at 121 °C and subsequently supplemented with 2% ethanol, 1.3% lactic acid, and 0.3% acetic acid. The concentrations of ethanol and organic acids were based on our previous report [17]. L. amylovorus LL34 (106 CFU/g, obtained by MRS broth culture) and A. pasteurianus LA10 (4 × 105 CFU/g, obtained by GYE broth culture) were co-inoculated into 200 g of the medium and statically incubated at 37 °C for 60 h. Samples were collected at 12 h intervals (0, 12, 24, 36, 48, and 60 h) after thoroughly mixing the medium. Each strain was individually inoculated as a control, and triplicate parallel experiments were conducted for each experimental group.
2.2.2. Enumeration of Strains
The number of L. amylovorus LL34 and A. pasteurianus LA10 in each sample was determined by plating on an MRS agar plate [18]. The two bacterial strains were distinguished based on colony morphology. The colony of L. amylovorus LL34 was larger and irregularly circular, while the colony of A. pasteurianus was smaller and exhibited a regular circular shape.
2.2.3. Determination of Total Acid, Lactic Acid, and Acetic Acid Content
Five grams of Cupei was mixed with 45 mL of sterile water and kept at 60 °C for 1 h. After cooling to 30 °C, the mixture was centrifuged at 10,000 g for 10 min, and the supernatant was collected for analysis. The total acid content was tested by titration with 1.0 mol/L NaOH using phenolphthalein as an indicator and expressed as g/100 g lactic acid.
Organic acid contents were analyzed with modifications from a previous report [17]. Briefly, 4 mL of supernatant was mixed with 1 mL of potassium ferrocyanide (106 g/L) and 1 mL of zinc sulfate (300 g/L), followed by centrifugation at 10,000 g for 10 min. The supernatant was extracted using Sep-Pak C18 cartridges, filtered through a 0.22 μm membrane, and analyzed by HPLC. A Hichrom Alltech OA-1000 column (300 × 6.5 mm, 9 μm) was employed with 9 mmol/L H2SO4 as the mobile phase at a flow rate of 0.6 mL/min. The injection volume was 10 μL, and the UV detector was set at 210 nm. A calibration curve was established using organic acid standard solutions, with concentration calculated versus peak area using the least-squares method.
2.2.4. Volatile Compounds
Volatile compounds were analyzed using gas chromatography–mass spectrometry (GC–MS; 5975C/6890N; Agilent, CA, USA) with an HP-5MS column (60 m × 0.32 mm, 1 μm) according to a previous report [17]. Compound identification was performed by comparing obtained data with the National Institute of Standards and Technology (NIST) Library 2020 (similarity index > 80%) and literature references. Methyl heptanoate (0.001 mg/mL) was used as an internal standard for semi-quantification.
2.2.5. Non-Volatile Compounds
Non-volatile compounds were determined using untargeted metabolomics via the UHPLC–Exactive HF-X system by Majorbio Co., Ltd. (Shanghai, China), following the report by Kang et al. [19].
2.3. Statistical Analysis
All analyses were performed in triplicate, and experimental data are presented as the mean ± standard deviation. Statistical analysis was performed via SPSS 22.0 (SPSS, Chicago, IL, USA). One-way analysis of variance (ANOVA) was performed with a 95% confidence interval (p < 0.05), and the mean comparison was performed via the least significant difference (LSD) test.
3. Results and Discussion
3.1. Enumeration of Strains in Pure Culture and Co-Culture
The growth of L. amylovorus LL34 and A. pasteurianus LA10 was measured in a pure culture and a co-culture (Figure 1A). The growth trends of A. pasteurianus LA10 in both cultures were similar, characterized by rapid initial growth within the first 24 h, followed by slower growth. The final biomass was 8.37 lg CFU/g in the pure culture and 8.50 lg CFU/g in the co-culture. In contrast, L. amylovorus LL34 demonstrated distinct growth behaviors: in the pure culture, its biomass increased significantly (p < 0.05), whereas, in the co-culture, the increase was not significant (p > 0.05), with the biomass increasing from 6.07 to only 6.44 lg CFU/g. These findings indicate that the presence of L. amylovorus LL34 had minimal impact on the growth of A. pasteurianus LA10, whereas the presence of A. pasteurianus LA10 may inhibit the growth of L. amylovorus LL34.
3.2. Changes in Total Acid Content in Pure Culture and Co-Culture
The total acid content in both the pure culture and the co-culture was measured (Figure 1B). In the pure culture of A. pasteurianus LA10 and the co-culture, the total acid content tended to increase as fermentation progressed. Specifically, the pure culture of A. pasteurianus LA10 increased from 13.15 to 26.16 mg/g, while the co-culture increased from 15.39 to 21.82 mg/g. Conversely, the pure culture of L. amylovorus LL34 exhibited no significant change in the total acid content, remaining stable from 14.94 mg/g to 14.79 mg/g (p > 0.05). These findings suggest that the acidogenic metabolism of A. pasteurianus LA10 was partially inhibited in the co-culture.
Different capital letters denote significant differences in the same strain at varying fermentation times, while different lowercase letters indicate significant differences between the different cultures at a single time point (p < 0.05). Abbreviations: ML, the pure culture of L. amylovorus LL34; MA, the pure culture of A. pasteurianus LA10; CL, L. amylovorus LL34 in the co-culture; CA, A. pasteurianus LA10 in the co-culture; L, the pure culture of L. amylovorus LL34; A, the pure culture of A. pasteurianus LA10; and CO, co-culture.
3.3. Changes in Lactic Acid and Acetic Acid Contents in Pure Culture and Co-Culture
The lactic acid and acetic acid contents in the pure culture and the co-culture were measured (Figure 1C,D). The results indicate that the lactic acid and acetic acid contents in the pure culture of L. amylovorus LL34 remained stable throughout fermentation, consistent with the total acid content. Conversely, both the pure culture of A. pasteurianus LA10 and the co-culture exhibited significant changes in lactic acid and acetic acid contents (p < 0.05). Specifically, the lactic acid content in the pure culture of A. pasteurianus LA10 decreased from 11.14 to 8.47 mg/g and from 10.91 to 10.02 mg/g in the co-culture. The acetic acid content in the pure culture of A. pasteurianus LA10 increased from 3.92 to 12.20 mg/g and from 3.62 to 9.53 mg/g in the co-culture. The decline in lactic acid content during later fermentation stages in the pure culture of A. pasteurianus LA10 and the co-culture may be attributed to the utilization of lactic acid by A. pasteurianus [20]. Notably, the acetic acid level was found to be lower in the co-culture compared to the pure culture of A. pasteurianus LA10 after 12 h incubation, indicating potential metabolic regulation of A. pasteurianus LA10 by L. amylovorus LL34.
3.4. Volatile Compounds in Pure Culture and Co-Culture
A total of 67 volatile compounds were identified using GC-MS, including acids (6), alcohols (8), aldehydes (11), esters (11), ketones (13), heterocycles (3), terpenes (2), and others (13) (Table 1). A. pasteurianus LA10 in the pure culture exhibited the most detection (39), followed by the co-culture (36), and L. amylovorus LL34 in the pure culture (34). To investigate the differences in volatile compounds in different cultures, an orthogonal partial least-squares discriminant analysis (OPLS-DA) model was established (Figure 2A), with 200 permutation tests conducted (Figure 2B). The model demonstrated a goodness of prediction (Q2) exceeding 0.5. The score plot revealed significant differences among the cultures.
Acids are important metabolites during fermentation, constituting 14.99–36.30% of volatile compounds. Acetic acid was the most abundant, and its relative content in the pure culture of A. pasteurianus LA10 (810.72 ± 235.26 μg/kg) exceeded that in the co-culture (607.97 ± 205.27 μg/kg), aligning with acetic acid determination.
The relative content of alcohols ranged from 8.54% to 26.49%, with ethanol being the predominant alcohol. The relative content of ethanol was the highest in the pure culture of L. amylovorus LL34 (506.91 ± 56.92 μg/kg), followed by the co-culture (393.39 ± 90.212 μg/kg) and the pure culture of A. pasteurianus LA10 (193.91 ± 30.37 μg)/kg. The findings indicate that the ethanol utilization ability of A. pasteurianus LA10 in the co-culture was influenced by L. amylovorus LL34, highlighting the impact of the co-culture on the growth and metabolism of A. pasteurianus LA10.
The relative contents of aldehydes, esters, and ketones ranged from 0.59% to 12.95%, 0.23% to 12.7%, and 2.53% to 8.28%, respectively. The relative content of benzaldehyde in the co-culture was the lowest. Additionally, flavor substances such as ethyl acetate and 3-hydroxy-2-butanone [21] were found to be lower in the co-culture compared to the pure culture of A. pasteurianus LA10. 3-Hydroxy-2-butanone, also known as acetoin, served as a precursor in the synthesis of tetramethylpyrazine in vinegar [5].
Heterocyclic compounds and terpenoids were detected. Heterocyclic compounds showed a higher relative abundance in all three cultures, while terpenoids had relatively lower proportions. Notably, the co-culture exhibited a higher relative content of 2-pentylfuran compared to the other two pure cultures. This compound is commonly found in fermented foods, imparting a fruity and milky aroma [22,23].
3.5. Non-Volatile Compounds in Pure Culture and Co-Culture
3.5.1. Metabolite Profile
A total of 13,343 peaks (7055 in positive mode and 6288 in negative mode) was observed using untargeted metabolomics analysis. Through annotation via the Human Metabolome Database (HMDB), 2465 metabolites were identified, predominantly comprising lipids and lipid molecules (631), organic acids and their derivatives (545), organic heterocyclic compounds (371), organooxygen compounds (305), and benzenes (226) (Figure 2C).
3.5.2. Differential Metabolite Analysis
The metabolite profiles of the pure culture and the co-culture were analyzed using principal component analysis (PCA) (Figure 3). Quality control (QC) sample clustering demonstrates the stability and reproducibility of the detection procedure. In positive mode, the first and second principal components contributed 15.00% and 13.80% of the variance, respectively. Similarly, in negative mode, the first and second principal components contributed 15.50% and 14.40% of the variance, respectively. The metabolite compositions in the co-culture and the pure culture of A. pasteurianus LA10 were similar, as evidenced by their overlapping positions in the PCA plot.
OPLS-DA was employed to obtain the variable influence on projections (VIPs) and p-values of the Student’s t-tests. Differential metabolites were identified as those with a VIP value > 1 and p < 0.05. Comparative metabolite analysis reveals 330 differential metabolites between the co-culture and the pure culture of Acetobacter LA10 and 441 differential metabolites between the co-culture and the pure culture of L. amylovorus LL34 (Figure 4).
Differential metabolites with top VIP values were selected between the co-culture and the pure culture of A. pasteurianus LA10 (Table 2). The upregulated metabolites after co-culture included phenyllactic acid, 3-phenyllactic acid, 4-vinylphenol, 6-hydroxyhexanoic acid, etc. Phenyllactic acid, produced by most lactic acid bacteria, exhibits broad-spectrum antibacterial properties [24] and serves as a metabolic marker for vinegar identification and classification [25]. Similar to phenyllactic acid, 6-hydroxyhexanoic acid demonstrates antioxidant and anti-inflammatory properties [26]. 4-Vinylphenol, a characteristic flavor compound, significantly contributes to the flavor formation of other fermented foods [27].
Differential metabolites with top VIP values were selected between the co-culture and the pure culture of L. amylovorus LL34 (Table 3). The upregulated metabolites after co-culture included scopoletin, isofraxidin, 5-Hydroxymethyl-2-furancarboxaldehyde, etc. Scopoletin and isofraxidin are both coumarin compounds with favorable biological characteristics [28,29] and can be isolated from plants. 5-Hydroxymethyl-2-furancarboxaldehyde is a major product of the Maillard reaction and can serve as an indicator of the adulteration of food products with acid-converted inverted syrups [30].
3.5.3. KEGG Metabolic Pathway Analysis
The metabolites were searched for in the KEGG database and enriched in the KEGG pathways. A total of 1124 metabolic pathways were annotated in the metabolome, with amino acid metabolism comprising the highest proportion (186 pathways), followed by lipid metabolism (154 pathways) and the biosynthesis of other secondary metabolites (134 pathways).
KEGG enrichment analysis reveals that differential metabolites between the co-culture and the pure culture of A. pasteurianus LA10 were mainly associated with arachidonic acid metabolism, glycerophospholipid metabolism, and phenylpropanoid biosynthesis (Figure 5A), while differential metabolites between the co-culture and the pure culture of L. amylovorus LL34 were mainly associated with the biosynthesis of phenylpropanoids, D-amino acid metabolism, arginine, and proline metabolism, as well as nucleotide metabolism (Figure 5B).
The presence of acids, particularly organic acids and amino acids, in vinegar is crucial to its flavor. The significant enrichment of acids and amino acid metabolism pathways in the co-culture indicates its vital impact on flavor development.
4. Conclusions
In this study, a bottom-up approach was employed to examine the interactions between lactic acid bacteria and acetic acid bacteria in a simulated Cupei medium for Sichuan bran vinegar. The results reveal that the co-culture inhibited the growth and metabolism of L. amylovorus LL34 while minimally affecting the growth of A. pasteurianus LA10 but suppressing its metabolic processes. Microbial interactions influence both volatile and non-volatile metabolite profiles. This investigation provides foundational insights into how dominant microorganism interactions modulate the quality of Sichuan bran vinegar. Future research should investigate strain interactions at the transcriptomic and proteomic levels and explore potential interactions involving three or more strains.
Author Contributions
J.L.: writing—original draft, writing—review and editing, investigation, validation, formal analysis. J.W. and X.A.: investigation, methodology, data curation. M.T., X.X. and X.H.: writing—original draft, data curation. Q.L., N.Z. and K.H.: methodology, writing—original draft, writing—review and editing. S.L.: conceptualization, supervision. A.L.: writing—original draft, writing—review and editing, conceptualization, supervision. All authors have read and agreed to the published version of the manuscript.
Funding
This work was financially supported by the Science and Technology Department of Sichuan Province (No. 2024NSFSC2079 and No. 2023ZHCG0081), the Sichuan Province Undergraduate Training Program for Innovation and Entrepreneurship (S202310626057), the Innovation and Demonstration of Industry and Education Integration in Feed Industrial Chain Transformation and Upgradation (Sichuan, China), the Shuangzhi Plan of Sichuan Agricultural University (2024ZYTS004), and the Open Found of Sichuan Dongpo Chinese Paocai Industrial Technology Research Institute.
Data Availability Statement
The data are provided in the text.
Conflicts of Interest
The remaining authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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Figure 1.
Index changes in pure culture and co-culture. (A) The number of L. amylovorus LL34 and A. pasteurianus LA10; (B) total acid content; (C) lactic acid content; (D) acetic acid content.
Figure 1.
Index changes in pure culture and co-culture. (A) The number of L. amylovorus LL34 and A. pasteurianus LA10; (B) total acid content; (C) lactic acid content; (D) acetic acid content.
Figure 2.
OPLS-DA (A), permutation test of OPLS-DA (B), and classification of compounds annotated in HMDB (C) in pure culture and co-culture. Note: (A,B): Difference analysis of volatile flavor components; (C): Metabonomic data analysis.
Figure 2.
OPLS-DA (A), permutation test of OPLS-DA (B), and classification of compounds annotated in HMDB (C) in pure culture and co-culture. Note: (A,B): Difference analysis of volatile flavor components; (C): Metabonomic data analysis.
Figure 3.
PCA plots of the pure culture and co-culture. (A) Positive mode; (B) negative mode. Abbreviation: L, pure culture of L. amylovorus LL34; A, pure culture of A. pasteurianus LA10; CO, co-culture.
Figure 3.
PCA plots of the pure culture and co-culture. (A) Positive mode; (B) negative mode. Abbreviation: L, pure culture of L. amylovorus LL34; A, pure culture of A. pasteurianus LA10; CO, co-culture.
Figure 4.
Volcano plot of differential metabolites. (A) LA10 co-culture and pure culture of A. pasteurianus; (B) LL34 co-culture and pure culture of L. amylovorus.
Figure 4.
Volcano plot of differential metabolites. (A) LA10 co-culture and pure culture of A. pasteurianus; (B) LL34 co-culture and pure culture of L. amylovorus.
Figure 5.
KEGG pathway enrichment analysis. (A) Differential metabolites between co-culture and pure culture of A. pasteurianus LA10; (B) differential metabolites between co-culture and pure culture of L. amylovorus LL34. Each bubble represents a metabolic pathway. The bubble size correlates with the abundance of metabolites enriched in the pathway.
Figure 5.
KEGG pathway enrichment analysis. (A) Differential metabolites between co-culture and pure culture of A. pasteurianus LA10; (B) differential metabolites between co-culture and pure culture of L. amylovorus LL34. Each bubble represents a metabolic pathway. The bubble size correlates with the abundance of metabolites enriched in the pathway.
Table 1.
Volatile compounds in pure culture and co-culture.
| Class | No. | Name | Relative Contents (μg/kg) | ||
|---|---|---|---|---|---|
| Pure Culture of L. amylovorus LL34 | Pure Culture of A. pasteurianus LA10 | Co-Culture of L. amylovorus LL34 and A. pasteurianus LA10 | |||
| Acids | 1 | Acetic acid | 262.26 ± 66.25 b | 810.72 ± 235.26 a | 607.97 ± 205.27 ab |
| 2 | Hexanoic acid | / | 62.84 ± 5.85 a | 58.88 ± 12.67 a | |
| 3 | Pentanoic acid | 31.63 ± 0.02 a | / | / | |
| 4 | 2-Methylbutanoic acid | / | 3.72 ± 2.89 a | / | |
| 5 | 3-Methylbutanoic acid | / | 3.31 ± 1.04 a | / | |
| 6 | 2-Methylpropanoic acid | / | 2.28 ± 0.49 a | / | |
| Alcohols | 7 | Ethanol | 506.91 ± 56.92 a | 193.91 ± 30.37 b | 393.39 ± 90.21 a |
| 8 | 1-Hexanol | 10.56 ± 0.75 a | 7.27 ± 0.25 c | 9.39 ± 0.03 b | |
| 9 | Cyclohexanemethanol, 4-methyl-, cis- | / | 4.13 ± 0.39 a | / | |
| 10 | α-Methyl-benzenemethanol | / | 2.2 ± 0.16 a | / | |
| 11 | Benzenemethanol, 4-methyl-.alpha.-(1-methyl-2-propenyl)-, (R,R)- | / | 0.21 ± 0.02 a | / | |
| 12 | 1-Octen-3-ol | / | / | 9.02 ± 0.78 a | |
| 13 | 1-Pentanol | 0.99 ± 0.2 a | / | 1.05 ± 0.02 a | |
| 14 | 2-Methyl-1,8-octanediol | 1.09 ± 0.33 a | / | / | |
| Aldehydes | 15 | Benzaldehyde | 115.46 ± 18.99 a | 10.5 ± 0.65 b | 9 ± 0.84 b |
| 16 | 3-Furaldehyde | 61.55 ± 6.4 a | / | / | |
| 17 | Methylal | / | / | 39.88 ± 32.55 a | |
| 18 | 5-Ethylcyclopent-1-enecarboxaldehyde | 37.74 ± 2.99 a | / | / | |
| 19 | Benzeneacetaldehyde | 15.59 ± 2.45 a | / | / | |
| 20 | Nonanal | 8 ± 1.12 a | 1.27 ± 0.1 b | 2.02 ± 0.16 b | |
| 21 | Heptanal | 7.68 ± 0.36 a | / | / | |
| 22 | Hexanal | 6.69 ± 5.41 a | / | / | |
| 23 | 2-Butenal | / | 2.54 ± 1.52 a | 4.8 ± 3.54 a | |
| 24 | Decanal | 0.94 ± 0.18 a | / | / | |
| 25 | Isophthalaldehyde | 0.41 ± 0.02 a | / | / | |
| Esters | 26 | Ethyl acetate | / | 167.98 ± 15.94 a | 158.19 ± 26.88 a |
| 27 | Methyl 2-hydroxypropanoate | / | 66.86 ± 19.81 a | 55.08 ± 45.24 a | |
| 28 | Propyl 2-hydroxypropanoate | / | / | 52.79 ± 59.97 a | |
| 29 | Ethyl 2-(methylamino)acetate | / | 28.21 ± 10.76 a | 35.5 ± 3.45 a | |
| 30 | Ethyl 2-hydroxypropanoate | / | 10.58 ± 0.31 b | 33.94 ± 2.26 a | |
| 31 | Allyl acetate | / | 4.49 ± 1.28 a | / | |
| 32 | Phenol, 2,6-bis(1,1-dimethylethyl)-4-methyl-, methylcarbamate | 3.02 ± 0.66 a | / | / | |
| 33 | Hexyl acetate | / | 2.07 ± 0.07 a | 1.77 ± 0.05 b | |
| 34 | 2-Ethylhexyl hexyl sulfite | 1.52 ± 0.24 a | 0.8 ± 0.78 a | 3.24 ± 2.31 a | |
| 35 | Methyl acetate | / | 1.03 ± 0.38 a | 1.11 ± 0.3 a | |
| 36 | Sulfurous acid, isobutyl pentyl ester | / | 0.45 ± 0.22 a | / | |
| Ketones | 37 | Acetyl methyl carbinol | / | 145.4 ± 31.4 a | 107.75 ± 20.93 a |
| 38 | Gamma-nonanoic lactone | 15.45 ± 2.34 a | 20.3 ± 0.4 a | 19.12 ± 3.95 a | |
| 39 | 2-Heptanone | 1.84 ± 0.47 b | 24.53 ± 1.48 a | / | |
| 40 | 5-Methyl-2-hexanone | 25.03 ± 1.57 a | 2.29 ± 0.21 b | 13.63 ± 15.89 ab | |
| 41 | 2-Nonanone | 1.04 ± 0.1 b | 3.96 ± 0.1 a | 3.55 ± 0.38 a | |
| 42 | Acetone | / | / | 6.97 ± 2.54 a | |
| 43 | 5-Methyl-4-hexen-3-one | / | 2.96 ± 0.32 a | / | |
| 44 | 3-Ethylcyclopentanone | / | / | 2.94 ± 0.15 a | |
| 45 | Acetophenone | 2.56 ± 0.34 a | / | 2.87 ± 0.26 a | |
| 46 | 3-Octen-2-one | 2.53 ± 0.15 a | / | 1.55 ± 0.18 b | |
| 47 | 4-Nonanone | / | 1.54 ± 0.04 a | 1.55 ± 0.24 a | |
| 48 | 2,5-Dimethyl-3-hexanone | 0.36 ± 0.2 a | 0.34 ± 0.1 a | / | |
| 49 | 2,2,5-Trimethylhexane-3,4-dione | 0.88 ± 0.16 a | / | / | |
| Heterocycles | 50 | 2-Pentylfuran | 817.05 ± 95.09 b | 833.04 ± 37.86 b | 1024.09 ± 37.76 a |
| 51 | 2-(1-Pentenyl)furan | 2.89 ± 0.58 a | 3.33 ± 0.21 a | 3.82 ± 0.95 a | |
| 52 | 2-Hexylfuran | 1.85 ± 0.22 a | / | / | |
| Terpenes | 53 | 3-Methyl-1-hexene | / | 0.83 ± 0.01 a | |
| 54 | 9-Methyl-1-undecene | 1.03 ± 0.12 a | / | / | |
| Others | 55 | 1H-Indene, octahydro-2,2,4,4,7,7-hexamethyl-, trans- | 9.48 ± 1.25 a | / | 9.33 ± 3.35 a |
| 56 | Naphthalene | 3.46 ± 0.54 a | 3.01 ± 0.14 a | 3.3 ± 1 a | |
| 57 | 1,2,4,5-Tetramethylbenzene | 2.32 ± 0.19 b | / | 3.17 ± 0.24 a | |
| 58 | 1H-Tetrazol-5-amine | / | 0.24 ± 0.08 a | 0.27 ± 0.03 a | |
| 59 | Semicarbazide | / | / | 2.89 ± 2.25 a | |
| 60 | (1-Ethylpropyl)benzene | / | / | 2.69 ± 0.35 a | |
| 61 | N-Isobutyl(phenyl)methanesulfonamide | / | / | 2.74 ± 0.56 a | |
| 62 | 2,4,5-Trimethyl-1,3-dioxolane | / | 1.72 ± 0 a | / | |
| 63 | 1,1,4a,5,6-Pentamethyldecahydronaphthalene | / | 0.96 ± 0 a | / | |
| 64 | 2-Acetylthiazole | 0.81 ± 0.05 a | / | / | |
| 65 | 2-Methoxy phenol | 0.59 ± 0.13 a | / | / | |
| 66 | Dihexyverine | / | 0.23 ± 0.05 a | / | |
| 67 | Ethoxyethene | / | 0.2 ± 0.04 a | / | |
Note: different superscript letters means significantly different (p < 0.05).
Table 2.
Partial differential metabolites between co-culture and pure culture of A. pasteurianus LA10.
Table 2.
Partial differential metabolites between co-culture and pure culture of A. pasteurianus LA10.
| Metabolite | Fold Change | Regulate | VIP Value |
|---|---|---|---|
| 8-Hydroxyguanine | 0.7166 | down | 8.2403 |
| 3-Hydroxy-4-methoxyphenyllactic acid | 1.2953 | up | 6.8915 |
| Phenyllactic acid | 1.1295 | up | 6.3087 |
| Xanthine amine | 0.8554 | down | 6.2165 |
| Franguloside | 1.1626 | up | 6.0155 |
| S-Adenosylhomocysteine | 1.1013 | up | 4.7833 |
| Phenylpyruvic acid | 0.9111 | down | 4.4769 |
| 5′-Methylthioadenosine | 0.9299 | down | 4.1068 |
| (E)-10-Hydroxy-8-decenoic acid | 1.0675 | up | 4.0472 |
| Ketoleucine | 0.9479 | down | 3.9116 |
| Enniatin B | 1.0441 | up | 3.8112 |
| 4-Vinylphenol | 1.0659 | up | 3.7345 |
| Ethyl 3-hydroxydodecanoate | 1.0993 | up | 3.7238 |
| 1,4,7,10,13,16-Hexaoxacyclooctadecane | 1.0604 | up | 3.4713 |
| 6-Hydroxyhexanoic acid | 1.0352 | up | 3.1451 |
| Uric acid | 0.9635 | down | 3.134 |
| 5-Chloro-2′-deoxyuridine | 1.0459 | up | 3.1175 |
| (2S,3R,4S,5R,6R)-6-Ethyloxane-2,3,4,5-tetrol | 1.0401 | up | 3.0507 |
| PC(18:2(9Z,12Z)/18:2(9Z,12Z)) | 0.9675 | down | 3.016 |
| 5-Methyl-2-furancarboxaldehyde | 0.9615 | down | 2.9399 |
| Enniatin B1 | 1.0264 | up | 2.9028 |
| Epitiostanol | 1.0326 | up | 2.8945 |
| 1-Hexanol | 1.0388 | up | 2.7946 |
Table 3.
Partial differential metabolites between co-culture and pure culture of L. amylovorus LL34.
Table 3.
Partial differential metabolites between co-culture and pure culture of L. amylovorus LL34.
| Metabolite | Fold Change | Regulate | VIP Value |
|---|---|---|---|
| L-Asparagine | 0.5834 | down | 8.7843 |
| Scopoletin | 1.7944 | up | 8.6923 |
| Iminodiacetic acid | 0.6175 | down | 8.0915 |
| 3a,7a-Dihydroxy-5b-cholestane | 1.4394 | up | 7.2836 |
| 4-Oxo-2-azetidinecarboxylic acid | 0.7232 | down | 7.162 |
| L-Aspartic acid | 0.7397 | down | 6.8104 |
| Ureidopropionic acid | 0.6903 | down | 6.8023 |
| Aspartic acid | 0.7887 | down | 6.5172 |
| Isofraxidin | 1.3725 | up | 6.3634 |
| 3-Indolebutyric acid | 1.2467 | up | 6.0585 |
| 2-(Carbamoylamino)propanoic acid | 0.8051 | down | 5.9903 |
| 5-Hydroxymethyl-2-furancarboxaldehyde | 1.2321 | up | 5.7925 |
| MALEAMIC ACID | 0.7766 | down | 5.659 |
| Tolmetin | 1.1964 | up | 5.379 |
| 4-Hydroxyvalproic acid | 1.1994 | up | 5.2886 |
| Cyclopropyl–methoxycarbonyl metomidate | 1.1838 | up | 5.281 |
| DG(22:4(7Z,10Z,13Z,16Z)/15:0/0:0) | 1.1599 | up | 5.1935 |
| Franguloside | 1.1716 | up | 5.142 |
| 3-Ethyl-5-hydroxy-4,5-dimethyl-pyrrolin-2-one | 1.1865 | up | 5.0692 |
| 1,2-Dilinolenoyl-3-(4-aminobutyryl)propane-1,2,3-triol | 1.1516 | up | 4.8926 |
| 3-Methoxyphenol sulfate | 1.175 | up | 4.7342 |
| 2-Succinylbenzoate | 1.1424 | up | 4.3289 |
| N-lactoyl-Methionine | 1.127 | up | 4.3233 |
| 5-Hydroxyvalproic acid | 1.1097 | up | 4.245 |
| S-Adenosylhomocysteine | 1.1109 | up | 4.1535 |
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Li, J.; Wu, J.; Tu, M.; Xiao, X.; Hu, K.; Li, Q.; Zhao, N.; Liu, A.; Ao, X.; Hu, X.; et al. Interaction Between Lactic Acid Bacteria and Acetic Acid Bacteria in Sichuan Bran Vinegar: Impact on Their Growth and Metabolites. Foods 2025, 14, 1471. https://doi.org/10.3390/foods14091471
AMA Style
Li J, Wu J, Tu M, Xiao X, Hu K, Li Q, Zhao N, Liu A, Ao X, Hu X, et al. Interaction Between Lactic Acid Bacteria and Acetic Acid Bacteria in Sichuan Bran Vinegar: Impact on Their Growth and Metabolites. Foods. 2025; 14(9):1471. https://doi.org/10.3390/foods14091471
Chicago/Turabian StyleLi, Jianlong, Jie Wu, Meiling Tu, Xue Xiao, Kaidi Hu, Qin Li, Ning Zhao, Aiping Liu, Xiaolin Ao, Xinjie Hu, and et al. 2025. "Interaction Between Lactic Acid Bacteria and Acetic Acid Bacteria in Sichuan Bran Vinegar: Impact on Their Growth and Metabolites" Foods 14, no. 9: 1471. https://doi.org/10.3390/foods14091471
APA StyleLi, J., Wu, J., Tu, M., Xiao, X., Hu, K., Li, Q., Zhao, N., Liu, A., Ao, X., Hu, X., & Liu, S. (2025). Interaction Between Lactic Acid Bacteria and Acetic Acid Bacteria in Sichuan Bran Vinegar: Impact on Their Growth and Metabolites. Foods, 14(9), 1471. https://doi.org/10.3390/foods14091471
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