Microbial characterization of Sichuan Baoning vinegar: lactic acid bacteria, acetic acid bacteria and yeasts.

Sichuan Baoning vinegar, a typical representative of Sichuan bran vinegar, is a famous traditional fermented food made from cereals in China. At present, there are few studies on microbial characterization of culturable microorganisms in solid-state fermentation of Sichuan bran vinegar. To comprehensively understand the diversity of lactic acid bacteria, acetic acid bacteria and yeasts, which play an important role in the fermentation of Sichuan bran vinegar, traditional culture-dependent methods combined with morphological, biochemical, and molecular identification techniques were employed to screen and identify these isolates. A total of 34 lactic acid bacteria isolates, 39 acetic acid bacteria isolates, and 48 yeast isolates were obtained. Lactic acid bacteria were dominated by Enterococcus durans, Leuconostoc citreum, Lactococcus lactis, and Lactiplantibacillus plantarum, respectively. Latilactobacillus sakei was the first discovery in cereal vinegar. Acetic acid bacteria were mainly Acetobacter pomorum and A. pasteurianus. The dominant yeast isolates were Saccharomyces cerevisiae, in addition to four non-Saccharomyces yeasts. DNA fingerprinting revealed that isolates belonging to the same species exhibited intraspecific diversity, and there were differences between phenotypic and genotypic classification results. This study further enriches studies on cereal vinegar and lays a foundation for the development of vinegar starters.

Changes of microbial communities and metabolites in the fermentation of persimmon vinegar by bioaugmentation fermentation.

To evaluate the effects of bioaugmentation fermentation inoculated with one ester-producing strain (Wickerhamomyces anomalus ZX-1) and two strains of lactic acid bacteria (Lactobacillus plantarum CGMCC 24035 and Lactobacillus acidophilus R2) for improving the flavor of persimmon vinegar, microbial community, flavor compounds and metabolites were analyzed. The results of microbial diversity analysis showed that bioaugmentation fermentation significantly increased the abundance of Lactobacillus, Saccharomyces, Pichia and Wickerhamomyces, while the abundance of Acetobacter, Apiotrichum, Delftia, Komagataeibacter, Kregervanrija and Aspergillus significantly decreased. After bioaugmentation fermentation, the taste was softer, and the sensory irritancy of acetic acid was significantly reduced. The analysis of HS-SPME-GC-MS and untargeted metabolomics based on LC-MS/MS showed that the contents of citric acid, lactic acid, malic acid, ethyl lactate, methyl acetate, isocitrate, acetoin and 2,3-butanediol were significantly increased. By multivariate analysis, 33 differential metabolites were screened out to construct the correlation between the differential metabolites and microorganisms. Pearson correlation analysis showed that methyl acetate, ethyl lactate, betaine, aconitic acid, acetoin, 2,3-butanediol and isocitrate positively associated with Wickerhamomyces and Lactobacillus. The results confirmed that the quality of persimmon vinegar was improved by bioaugmentation fermentation.

Effect of vinegar steaming on the composition and structure of Schisandra chinensis polysaccharide and its anti-colitis activity.

In this study, infrared spectroscopy, high-performance liquid chromatography, and matrix-assisted laser desorption ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) technology were applied to systematically explain the Schisandra chinensis's polysaccharide transformation in configuration, molecular weight, monosaccharide composition, and anti-ulcerative colitis (UC) activity after vinegar processing. Scanning electron microscopic results showed that the appearance of S. chinensis polysaccharide changed significantly after steaming with vinegar. The MALDI-TOF-MS results showed that the mass spectra of raw S. chinensis polysaccharides (RSCP) were slightly lower than those of vinegar-processed S. chinensis polysaccharides (VSCP). The RSCP showed higher peaks at m/z 1350.790, 2016.796, and 2665.985, all with left-skewed distribution, and the molecular weights were concentrated in the range of 1300-3100, with no higher peak above m/z 5000. The VSCPs showed a whole band below m/z 3000, with m/z 1021.096 being the highest peak, and the intensity decreased with the increase of m/z. In addition, compared to RSCPs, VSCPs can significantly increase the content of intestinal short-chain fatty acids (SCFAs). This study showed that the apparent morphology and molecular weight of S. chinensis's polysaccharides significantly changed after steaming with vinegar. These changes directly affect its anti-UC effect significantly, and its mechanism is closely related to improving the structure and diversity of gut microbiota and SCFA metabolism.

Two Omics Methods Expose Anti-Depression Mechanism of Raw and Vinegar-Baked Bupleurum Scorzonerifolium Willd.

Bupleurum scorzonerifolium willd. (BS) and its vinegar-baked product (VBS) has been frequently utilized for depression management in clinical Chinese medicine. This paper aims to elucidate the antidepressant mechanism of BS and VBS from the perspectives of metabonomics and gut microbiota. A rat model of depression was established by CUMS combined with feeding alone to evaluate the antidepressant effects of BS and VBS. UPLC-Q-TOF-MS/MS-based metabolomics and 16S rRNA sequencing of rat feces were applied and the correlation of differential metabolic markers and intestinal floras was analyzed. The result revealed that BS and VBS significantly improved depression-like behaviors and the levels of monoamine neurotransmitters in CUMS rats. There were 27 differential endogenous metabolites between CUMS and normal rats, which were involved in 8 metabolic pathways. Whereas, BS and VBS could regulate 18 and 20 metabolites respectively, wherein fifteen of them were shared metabolites. On the genus level, BS and VBS could regulate twenty-five kinds of intestinal floras in CUMS rats, that is, they increased the abundance of beneficial bacteria and decreased the abundance of harmful bacteria. In conclusion, both BS and VBS exert excellent antidepressant effects by regulating various metabolic pathways and ameliorating intestinal microflora dysfunction.

Chemometrics-based Chemical Analysis of Myrrh and Its Vinegar-processed Products by UPLC-MS/MS.

Myrrh is widely used in clinical practice but accompanied by obvious toxicity. According to traditional Chinese medicines theory, processing with vinegar can effectively reduce its toxicity. However, the detoxification processing technology of Myrrh and the corresponding mechanism have been unclear. The objective of this study is to systematically analyze the variation in chemical composition of raw Myrrh and its processed products using UPLC-Q-TOF-MS/MS coupled with chemometrics. A total of 75 compounds including 56 sesquiterpenoids, 2 diterpenoids, 15 triterpenoids and 2 other types were identified. Raw Myrrh and its processed products were divided into two major groups, and 14 chemical markers were selected out by principal component analysis and partial least square discriminant analysis. Additionally, the exact content of 5 representative chemical markers was determined to be significantly reduced after vinegar-processing by UPLC-QQQ-MS/MS. Moreover, multivariate statistical analysis and the quantitative results comprehensively indicated that the optimized processing method was processing at a ratio of 200 : 5 (Myrrh:vinegar). This research provides not only a reliable foundation for the study of Myrrh, but also a scientific reference for clinical use of this herb.

Chemical profiling and quality evaluation of raw and vinegar-processing frankincense by multiple UPLC-MS/MS techniques.

INTRODUCTION: Frankincense is used for analgesic, tumor-suppressive, and anti-inflammatory treatments in Traditional Chinese Medicine but poses toxicological concerns. Vinegar processing is a common technique used to reduce the toxicity of frankincense. OBJECTIVE: This study aimed to investigate the chemical composition and quality evaluation of raw and vinegar-processing frankincense by multiple UPLC-MS/MS techniques. Additionally, we purposed refining the vinegar processing technique and identifying potentially harmful ingredients in the raw frankincense. METHODOLOGY: Sub-chronic oral toxicity studies were conducted on raw and vinegar-processing frankincense in rats. The composition of frankincense was identified by UPLC-Q-TOF-MS/MS. Chemometrics were used to differentiate between raw and vinegar-processing frankincense. Potential chemical markers were identified by selecting differential components, which were further exactly determined by UPLC-QQQ-MS/MS. Moreover, the viability of the HepG2 cells of those components with reduced contents after vinegar processing was assessed. RESULTS: The toxicity of raw frankincense is attenuated by vinegar processing, among which vinegar-processing frankincense (R40) (herb weight: rice vinegar weight = 40:1) exhibited the lowest toxicity. A total of 83 components were identified from frankincense, including 40 triterpenoids, 37 diterpenoids, and 6 other types. The contents of six components decreased after vinegar-processing, with the lowest levels in R40. Three components, specifically 3α-acetoxy-11-keto-ß-boswellic acid (AKBA), 3α-acetoxy-α-boswellic acid (α-ABA), and 3α-acetoxy-ß-boswellic acid (ß-ABA), inhibited the viability of HepG2 cells. The processing of frankincense with vinegar at a ratio of 40:1 could be an effective method of reducing the toxicity in raw frankincense. CONCLUSION: Our research improves understanding of the toxic substance basis and facilitates future assessments of frankincense quality.

Implementation of a Novel Method for Processing Proteins from Acetic Acid Bacteria via Liquid Chromatography Coupled with Tandem Mass Spectrometry.

Acetic acid bacteria (AAB) and other members of the complex microbiotas, whose activity is essential for vinegar production, display biodiversity and richness that is difficult to study in depth due to their highly selective culture conditions. In recent years, liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) has emerged as a powerful tool for rapidly identifying thousands of proteins present in microbial communities, offering broader precision and coverage. In this work, a novel method based on LC-MS/MS was established and developed from previous studies. This methodology was tested in three studies, enabling the characterization of three submerged acetification profiles using innovative raw materials (synthetic alcohol medium, fine wine, and craft beer) while working in a semicontinuous mode. The biodiversity of existing microorganisms was clarified, and both the predominant taxa (Komagataeibacter, Acetobacter, Gluconacetobacter, and Gluconobacter) and others never detected in these media (Asaia and Bombella, among others) were identified. The key functions and adaptive metabolic strategies were determined using comparative studies, mainly those related to cellular material biosynthesis, energy-associated pathways, and cellular detoxification processes. This study provides the groundwork for a highly reliable and reproducible method for the characterization of microbial profiles in the vinegar industry.

Separation and Detection of Catechins and Epicatechins in Shanxi Aged Vinegar Using Solid-Phase Extraction and Hydrophobic Deep Eutectic Solvents Combined with HPLC.

This research presents a new, eco-friendly, and swift method combining solid-phase extraction and hydrophobic deep eutectic solvents (DES) with high-performance liquid chromatography (SPE-DES-HPLC) for extracting and quantifying catechin and epicatechin in Shanxi aged vinegar (SAV). The parameters, such as the elution solvent type, the XAD-2 macroporous resin dosage, the DES ratio, the DES volume, the adsorption time, and the desorption time, were optimized via a one-way experiment. A central composite design using the Box-Behnken methodology was employed to investigate the effects of various factors, including 17 experimental runs and the construction of three-dimensional response surface plots to identify the optimal conditions. The results show that the optimal conditions were an HDES (tetraethylammonium chloride and octanoic acid) ratio of 1:3, an XAD-2 macroporous resin dosage of 188 mg, and an adsorption time of 11 min. Under these optimal conditions, the coefficients of determination of the method were greater than or equal to 0.9917, the precision was less than 5%, and the recoveries ranged from 98.8% to 118.8%. The environmentally friendly nature of the analytical process and sample preparation was assessed via the Analytical Eco-Scale and AGREE, demonstrating that this method is a practical and eco-friendly alternative to conventional determination techniques. In summary, this innovative approach offers a solid foundation for the assessment of flavanol compounds present in SAV samples.

Exploring the Impact of Various Wooden Barrels on the Aromatic Profile of Aceto Balsamico Tradizionale di Modena by Means of Principal Component Analysis.

The study examines the unique production process of Aceto Balsamico Tradizionale di Modena PDO (ABTM), emphasizing its complex phases and the impact of raw materials and artisanal skill on its flavor characteristics. Analytical tests focused on the volatile composition of vinegars from different wood barrels at different aging stages, using solid-phase micro-extraction (SPME) coupled with gas chromatography, either with mass spectrometry (GC/MS) or flame ionization detector (FID). Multivariate analysis, including principal component analysis (PCA), was employed to investigate the presence of peculiarities among the volatile profiles of samples of different barrel origin. The research focuses on characterizing the volatile composition of vinegars sourced from individual wood barrels, such as Cherry, Chestnut, Mulberry, Juniper, and Oak. Although it was not possible to identify molecules directly connected to the woody essence, some similarities emerged between vinegar samples from mulberry and cherry barrels and between those of juniper and oak. The former group is characterized by analytes with high molecular weights, such as furfural and esters, while the latter group shows more intense peaks for ethyl benzoate. Moreover, ethyl benzoate appears to predominantly influence samples from chestnut barrels. Due to the highly complex production process of ABTM, where each battery is influenced by several factors, this study's findings are specific to the current experimental conditions.

Investigating the synergistic effects of apple vinegar and deep eutectic solvent as natural antibiotics: an experimental and COSMO-RS analysis.

The present investigation examines the antimicrobial and antifungal characteristics of natural deep eutectic solvents (NADES) and apple vinegar in relation to a diverse array of bacterial and fungal strains. The clinical bacterial strains, including gram-negative and gram-positive, and the fungal pathogen Candida albicans, were subjected to solid medium diffusion to determine the inhibitory effects of these compounds. The results show that NADES has superior antimicrobial and antifungal action compared to apple vinegar. The observed inhibitory zones for apple vinegar and NADES varied in length from 16.5 to 24.2 and 16 to 52.5 mm, respectively. The results obtained indicate that no synergy is observed for this mixture (50% AV + 50% NADES). The range of values for bactericidal concentrations (MBC) and minimal inhibitory concentrations (MIC) was 0.0125 to 0.2 and 0.0125 to 0.4 µl/ml, respectively. Antibacterial and antifungal chemicals may be found in apple vinegar and NADES, with NADES offering environmentally safe substitutes for traditional antibiotics. Additional investigation is suggested to refine these compounds for a wide range of bacteria, which could create antimicrobial solutions that are both highly effective and specifically targeted, thereby offering extensive potential in medicine and the environment.

Comparative study on the use of seasoned or unseasoned casks made of wood from different origins for the ageing of Sherry vinegar.

BACKGROUND: In the present study, the ageing process of Sherry vinegar in used (seasoned) or new casks made of chestnut, American oak, Spanish oak or French oak wood has been investigated, considering that no research has investigated whether this seasoning has a definite influence on the final composition of the aged beverage. The polyphenolic and volatile contents of the aged vinegars were determined and their sensory properties were evaluated. Different statistical tools were applied to the data collected. RESULTS: With respect to polyphenolic contents, ageing time was the most influential factor, followed by the seasoned-cask factor. The type of wood was only significant for gallic acid, p-hydroxybenzoic acid, methylfurfural, ethyl gallate, ferulic acid, coniferyl aldehyde and sinapaldehyde. Principal component analysis according to polyphenols did not allow the samples to be differentiated, whereas cluster analysis revealed a slight grouping trend according to ageing time and seasoning of the wood. In relation to volatile compounds, variance analysis revealed that, again, ageing time and cask-seasoning were the most significant factors, with the samples clustering according to these two parameters. Following the sensory study, a clear difference between seasoned and new cask vinegars could be established as a result of the high scores in olfactory quality obtained for those vinegars aged in new casks. This was probably because of an excess of the descriptor 'ethyl acetate' exhibited by seasoned-cask Sherry vinegars. CONCLUSION: The previous seasoning of the casks together with the ageing time conditioned the composition of the vinegars aged in casks of different botanical origin, which translated into differences at a sensory level. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Real-time PCR-based quantitative microbiome profiling elucidates the microbial dynamic succession in backslopping fermentation of Taiwanese pickled cabbage.

BACKGROUND: Microbiota succession determines the flavor and quality of fermented foods. Quantitative PCR-based quantitative microbiome profiling (QMP) has been applied broadly for microbial analysis from absolute abundance perspectives, transforming microbiota ratios into counts by normalizing 16S ribosomal RNA (16S rRNA) gene sequencing data with gene copies quantified by quantitative PCR. However, the application of QMP in fermented foods is still limited. RESULTS: QMP elucidated microbial succession of Taiwanese pickled cabbage. In the spontaneous first-round fermentation (FR), the 16S rRNA gene copies of total bacteria increased from 6.1 to 10 log copies mL-1. The dominant lactic acid bacteria genera were successively Lactococcus, Leuconostoc and Lactiplantibacillus. Despite the decrease in the proportion of Lactococcus during the succession, the absolute abundance of Lactococcus still increased. In the backslopping second-round fermentation (SR), the total bacteria 16S rRNA gene copies increased from 7.6 to 9.9 log copies mL-1. The addition of backslopping starter and vinegar rapidly led to a homogenous microbial community dominated by Lactiplantibacillus. The proportion of Lactiplantibacillus remained consistently around 90% during SR, whereas its absolute abundance exhibited a continuous increase. In SR without vinegar, Leuconostoc consistently dominated the fermentation. CONCLUSION: The present study highlights that compositional analysis would misinterpret microbial dynamics, whereas QMP reflected the real succession profiles and unveiled the essential role of vinegar in promoting Lactiplantibacillus dominance in backslopping fermentation of Taiwanese pickled cabbage. Quantitative microbiome profiling (QMP) was found to be a more promising approach for the detailed observation of microbiome succession in food fermentation compared to compositional analysis. © 2024 Society of Chemical Industry.

Deciphering the core microbiota in open environment solid-state fermentation of Beijing rice vinegar and its correlation with environmental factors.

BACKGROUND: Rice vinegar is a popular cereal vinegar worldwide and is typically produced in an open environment, and the ecosystem of solid-state fermentation is complicated and robust. The present study aimed to reveal the shaping force of the establishment of the ecosystem of Beijing rice vinegar, the core function microbiota and their correlation with critical environmental factors. [Correction added after first online publication on 29 May 2024; the word "worldwide" has been removed from the first sentence under the section Background.] RESULTS: The experimental findings revealed the changes in environmental factors, major metabolites and microbial patterns during Beijing rice vinegar fermentation were obtained. The major metabolites accumulated at the middle and late acetic acid fermentation (AAF) periods. Principal coordinates and t-test analyses revealed the specific bacterial and fungal species at corresponding stages. Kosakonia, Methlobacterium, Sphingomonas, unidentified Rhizobiaceae, Pseudozyma and Saccharomycopsis dorminated during saccharification and alcohol fermentation and early AAF, whereas Lactococcus, Acetobacter, Rhodotorula and Kazachstania dominated the later AAF stages. Canonical correspondence analysis of environmental factors with core microbiota. Temperature and total acid were the most significant factors correlated with the SAF bacterial profile (Pediococcus, Weissella, Enterococcus and Kosakonia). Ethanol was the most significant factor between AAF1 and AAF3, and mainly affected Acetobacter and Lactobacillus. Conversely, ethanol was the most significant factor in the SAF, AAF1 and AAF3 fungi communities; typical microorganisms were Saccharomyces and Malassezia. Furthermore, the predicted phenotypes of bacteria and their response to environmental factors were evaluated. CONCLUSION: In conclusion, the present study has provided insights into the process regulation of spontaneous fermentation and distinguished the key driving forces in the microbiota of Beijing rice vinegar fermentation. © 2024 Society of Chemical Industry.

Orange passion fruit (Passiflora caerulea L.) as a new raw material for acetic fermentation: evaluation of organic acids and phenolic profile, in vitro digestion, and biological activities.

BACKGROUND: This study evaluated for the first time the potential of orange passion fruit as a base for alcoholic and acetic fermentations, with a view to assessing its profile of organic acids and polyphenols, in vitro digestion, and biological activities. RESULTS: In terms of aliphatic organic acids, malic acid was the majority in the wine (3.19 g L-1), while in the vinegar, it was acetic acid (46.84 g L-1). 3,4-Dihydroxybenzoic acid (3,4-DHB) was the major phenolic compound in the wine and vinegar samples (3443.93 and 2980.00 µg L-1, respectively). After the in vitro gastrointestinal simulation stage, the wine showed high bioaccessibility for the compounds sinipaldehyde (82.97%) and 2,4-dihydroxybenzoic acid (2,4-DHBA, 81.27%), while the vinegar exhibited high bioaccessibility for sinipaldehyde (89.39%). Through multivariate analysis, it was observed that 3,4-DHB was highly concentrated in the different digested fractions obtained from the wine. In contrast, in the vinegar, the stability of isorahmenetin and Quercetin 3-o-rhamnoside was observed during the in vitro digestion simulation. Lastly, the vinegar stood out for its inhibition rates of α-amylase (23.93%), α-glucoside (18.34%), and angiotensin-converting enzyme (10.92%). In addition, the vinegar had an inhibitory effect on the pathogenic microorganisms Salmonella enteritidis, Escherichia coli, and Listeria monocytogenes. CONCLUSION: Orange passion fruit has proved to be a promising raw material for the development of fermented beverages. Therefore, this study provides an unprecedented perspective on the use and valorization of orange passion fruit, contributing significantly to the advancement of knowledge about fermented products and the associated nutritional and functional possibilities. © 2024 Society of Chemical Industry.

Exploring the correlation of metabolites changes and microbial succession in solid-state fermentation of Sichuan Sun-dried vinegar.

BACKGROUND: The traditional Sichuan Sun-dried vinegar (SSV) with unique flavor and taste is believed to be generated by the solid-state fermentation craft. However, how microorganisms and their metabolites change along with fermentation has not yet been explored. RESULTS: In this study, our results demonstrated that the middle and late stages of SSV fermentation were the periods showing the largest accumulation of organic acids and amino acids. Furthermore, in the bacterial community, the highest average relative abundance was Lactobacillus (ranging from 37.55 to 92.50%) in all fermentation stages, while Acetobacters ranked second position (ranging from 20.15 to 0.55%). The number of culturable lactic acid bacteria is also increased during fermentation process (ranging from 3.93 to 8.31 CFU/g). In fungal community, Alternaria (29.42%), Issatchenkia (37.56%) and Zygosaccharomyces (69.24%) were most abundant in different fermentation stages, respectively. Interestingly, Zygosaccharomyces, Schwanniomyces and Issatchenkia were first noticed as the dominant yeast genera in vinegar fermentation process. Additionally, spearman correlation coefficients exhibited that Lactobacillus, Zygosaccharomyces and Schwanniomyces were significant correlation with most metabolites during the fermentation, implying that these microorganisms might make a significant contribution to the flavor formation of SSV. CONCLUSION: The unique flavor of SSV is mainly produced by the core microorganisms (Lactobacillus, Zygosaccharomyces and Schwanniomyces) during fermentation. This study will provide detailed information related to the structure of microorganism and correlation between changes in metabolites and microbial succession in SSV. And it will be very helpful for proposing a potential approach to monitor the traditional fermentation process.

Evaluation of probiotic properties of Levilactobacillus brevis isolated from hawthorn vinegar.

Probiotic microorganisms are increasing their interest today due to the benefits they provide to humans. Vinegar is the process of processing foods containing carbohydrates that can be fermented by acetic acid bacteria and yeasts. Hawthorn vinegar is also important in terms of amino acids, aromatic compounds, organic acids, vitamins and minerals it contains. Depending on the variety of microorganisms in it, the content of hawthorn vinegar changes, especially its biological activity. Bacteria were isolated from handmade hawthorn vinegar obtained in this study. After performing its genotypic characterization, it has been tested that it can grow in low pH environment, survive in artificial gastric and small intestinal fluid, survive against bile acids, surface adhesion characteristics, antibiotic susceptibility, adhesion, and degrade various cholesterol precursors. According to the results obtained, the studied isolate is Levilactobacillus brevis, it can reproduce best at pH 6.3, survives 72.22% in simulated gastric juice, 69.59% in small intestinal fluid, and 97% adhesion to HTC-116. Partially reproduces even in the presence of 2% ox-bile, surface hydrophobicity is 46.29% for n-hexadecane. It has been determined that it can degrade 4 different cholesterol precursors except for Sodium thioglycolate and is generally resistant to antibiotics except for CN30 and N30. Considering the experimental findings of Levilactobacillus brevis isolated from hawthorn vinegar for the first time, it can be said that Levilactobacillus brevis has probiotic properties.

Study on the quality difference of Cyperus rotundus before and after vinegar processing based on ultra-high-performance liquid chromatography-quadrupole-time of flight-mass spectrometry and molecular network combined with color parameters.

Cyperus rotundus is the dry rhizome of the Cyperaceae plant Cyperus. Although there are two types of processed products in clinics, their quality differences are not clear, and the identification methods are more complex. In this study, the chemical composition of different processed products of Cyperus rotundus was characterized using ultra-high-performance liquid chromatography-quadrupole-time of flight-mass spectrometry and molecular network analysis, to identify the potential chemical markers and to establish a quick and simple color-based discrimination method. Among the 65 compounds analyzed, 12 showed significant differences. Observing the color, the surface brightness (L*) of Cyperus rotundus decreased after vinegar processing, while red (a*) and yellow (b*) values increased. These color values correlated significantly with chemical compositions. Finally, a color discriminant function was established and verified for raw Cyperus rotundus and vinegar-processing Cyperus rotundus. Based on this study, Cyperus rotundus' quality can be effectively controlled and provides a method for the comprehensive characterization of chemical components and chemical markers of other traditional Chinese medicine and processed products, as well as new ideas and methods in identification and quality evaluation.

Dissecting chemical markers for controlling "Paozhi" method of traditional Chinese medicine with untargeted metabolomics: Vinegar-baked Euphorbia kansui as a case study.

The processing of Traditional Chinese Medicine requires the appropriate parameters, while the specific chemical markers are still absent to obtain the optimized processing. In this study, we used vinegar-baked Euphorbia kansui as a case to dissect the chemical markers for the baking process using untargeted metabolomics. The robust chemical markers were selected based on the three rules, correlation, significant difference, and controllability. All the differential features were categorized based on their mass defects. After the differential analysis, 310 differential compounds were screened out and could be mainly divided into six categories: diacylglycerols and triacylglycerols demonstrated increasing trends with the baking time in the discriminant model, while ingenane-type diterpenes, jatrophane-type diterpenes, fatty acid esters, and fatty acids had decreasing trends. It was unexpected to find that the diterpenes did not correlate with the baking time. Only very few compounds meet the three rules. They were validated with a high-performance liquid chromatography method. Finally, only 13-Hydroxy-9,11-octadecadienoic acid and its isomer 9-Hydroxy-10,12-octadecadienoic acid could be used further to differentiate the commercial vinegar-baked Euphorbia kansui. It would be of interest to evaluate whether these two compounds could be utilized as markers to control more processing methods in future studies.

Magnesium in dairy cattle nutrition: A meta-analysis on magnesium absorption in dairy cattle and assessment of simple solubility tests to predict magnesium availability from supplemental sources.

Supplemental Mg sources differ in bioavailability, and solubility is one of the determining factors. We explored whether and which in vitro solubility tests could reliably differentiate the quality of supplemental Mg sources. In experiment 1, we compared 3 chemical methods using an acetic acid solution (50 mL/L, termed vinegar test), a 1 M ammonium nitrate solution, and an artificial rumen buffer fluid without rumen microbiota. The Mg solubility results suggested the vinegar test was the best method due to its robustness, simplicity, and reproducibility. In experiment 2, we validated the reliability of the vinegar test using 4 MgO sources from experiment 1 and 12 new MgO sources plus a laboratory-grade MgO as a standard. Accordingly, we repeated the vinegar test with short (0.5 h) and long (3.0 h) incubation times on these sources and then conducted ruminal incubations in 24-h batch culture experiments. The repeated vinegar test resulted in similar results as in experiment 1. Linear regression across both experiments showed the soluble Mg content (g/kg) = 44.46 (±2.55) × pH - 142.9 (±14.9), root mean square error (RMSE) = 10.2, P slope <0.001, and concordance correlation coefficient (CCC) = 0.953. The predictable pH range was from 4 to 6. The equation cannot be applied to low-alkaline sources such as Mg sulfate, Mg acetate, or a group of MgO with exceptionally high alkaline properties showing a cluster of pH above 8.5. Solubility of the MgO sources in the vinegar test ranged from 5 to 35%, whereas the 24-h ruminal incubations led to more solubility (15-70%). Nevertheless, the differences among most MgO sources were parallel to the data from the in vitro rumen solubility. Next, we performed a meta-analysis of published studies (21 studies, 94 treatments) to assess the true Mg absorption in vivo and potential factors affecting Mg absorption in dairy cows. It appeared that on average dairy cows absorbed about 20% of the Mg intake (range 10-40%), regardless of their lactation status. We revealed a new strategy to predict Mg absorption relative to dietary K as follows: true Mg absorption (g/d) = 0.3395 (±0.025, P < 0.001) × Mg intake (g/d) - 1.9273 (±1.16, P = 0.11) when dietary K ≤20 g/kg DM, and 0.154 (±1.06, P = 0.05) + 0.209 (±0.026, P < 0.001) × Mg intake (g/d) when dietary K >20 g/kg DM (RMSE = 2.19). This strategy improved the accuracy of prediction as compared with the existing prediction (CCC = 0.922 vs. 0.845). Still, over- or underestimations inherent to individual studies were evident and might be related to unaccountable factors, especially the quality of supplemental Mg sources. In conclusion, the vinegar test is a useful tool to rank inorganic Mg sources with alkaline properties. Including in vitro solubility data in Mg nutrition research could help to refine the prediction of bioavailable Mg contents and increase precision in feed formulation.

Green remediation of Ni, Zn, and Cu in an electroplating contaminated site by wood vinegar with optimization and risk assessment.

Wood vinegar (WV) is a renewable organic compound, possessing characteristics such as high oxygenated compound content and low negative impact on soil. Based on its weak acid properties and complexing ability to potentially toxic elements (PTEs), WV was used to leach Ni, Zn, and Cu contaminated soil in electroplating sites. In addition, the response surface methodology (RSM) based on the Box-Behnken design (BBD) was established to clarify the interaction between each single factor, and finally completed the risk assessment of the soil. The amounts of PTEs leached from the soil climbed with the increase of WV concentration, liquid-solid ratio, and leaching time, while they surged with the decrease of pH. Under optimal leaching circumstances (the concentration of WV= 100 %; washing time= 919 min; pH= 1.00), the removal rates of Ni, Zn, and Cu could reach 91.7 %, 57.8 %, and 65.0 %, respectively, and the WV-extracted PTEs were mainly from the Fe-Mn oxides fraction. After leaching, the Nemerow integrated pollution index (NIPI) decreased from an initial value of 7.08 (indicating severe pollution) to 0.450 (indicating no pollution). The potential ecological risk index (RI) dropped from 274 (medium level) to 39.1 (low level). Additionally, the potential carcinogenic risk (CR) values reduced by 93.9 % for both adults and children. The results revealed that the washing process significantly reduced the pollution level, potential ecological risk, and health risk. Coupled with FTIR and SEM-EDS analysis, the mechanism of WV removal of PTEs could be explained from three aspects: acid activation, H+ ion exchange, and functional group complexation. In summary, WV is an eco-friendly and high-efficiency leaching material for the remediation of PTEs polluted sites, which will maintain soil function and protect human health.