Exploration of carbonyl compounds in red-fleshed kiwifruit wine and perceptual interactions among non-volatile organic acids.

Carbonyl compounds are vital constituents that contribute to the flavor profile of alcoholic beverages. We examined 3-nitrophenylhydrazine as a derivatizing reagent for the measurement of 34 carbonyl compounds using UPLC-MS/MS. Adding formic acid and sodium acetate to the mobile phase significantly enhanced the detection limit of carbonyl compounds. The technique exhibited a notable extraction efficiency, yielding recovery percentages ranging from 83.6% to 117.1%, coupled with exceptional sensitivity, as evidenced by detection limits spanning from 0.07 µg/L to 4.80 µg/L. The relative standard deviation was <6.9%, indicating the precision and reliability of the analytical methodology. The method was verified by analyzing carbonyl compounds from red-fleshed kiwifruit wine. Furthermore, sensory assessment revealed that the amalgamation of tartaric acid, malic acid, and citric acid contributes to sour taste perception at sub-threshold concentrations through an additive interaction with supra-threshold non-volatile organic acids such as lactic acid and acetic acid.

Major Active Metabolite Characteristics of Dendrobium officinale Rice Wine Fermented by Saccharomyces cerevisiae and Wickerhamomyces anomalus Cofermentation.

Rice, supplemented with Dendrobium officinale, was subjected to cofermentation using Saccharomyces cerevisiae FBKL2.8022 (Sc) and Wickerhamomyces anomalus FBKL2.8023 (Wa). The alcohol content was determined with a biosensor, total sugars with the phenol-sulfuric acid method, reducing sugars with the DNS method, total acids and total phenols with the colorimetric method, and metabolites were analyzed using LC-MS/MS combined with multivariate statistics, while metabolic pathways were constructed using metaboAnalyst 5.0. It was found that the quality of rice wine was higher with the addition of D. officinale. A total of 127 major active substances, mainly phenols, flavonoids, terpenoids, alkaloids, and phenylpropanoids, were identified. Among them, 26 substances might have been mainly metabolized by the mixed-yeasts fermentation itself, and 10 substances might have originated either from D. officinale itself or from microbial metabolism on the newly supplemented substrate. In addition, significant differences in metabolite could be attributed to amino acid metabolic pathways, such as phenylalanine metabolism and alanine, aspartate, and glutamate metabolism. The characteristic microbial metabolism of D. officinale produces metabolites, which are α-dihydroartemisinin, alantolactone, neohesperidin dihydrochalcone, and occidentoside. This study showed that mixed-yeasts cofermentation and fermentation with D. officinale both could increase the content of active substances in rice wine and significantly improve the quality of rice wine. The results of this study provide a reference for the mixed fermentation of brewer's yeast and non-yeast yeasts in rice wine brewing.

Quorum sensing-mediated microbial interactions: Mechanisms, applications, challenges and perspectives.

Microbial community in natural or artificial environments playes critical roles in substance cycles, products synthesis and species evolution. Although microbial community structures have been revealed via culture-dependent and culture-independent approaches, the hidden forces driving the microbial community are rarely systematically discussed. As a mode of cell-to-cell communication that modifies microbial interactions, quorum sensing can regulate biofilm formation, public goods secretion, and antimicrobial substances synthesis, directly or indirectly influencing microbial community to adapt to the changing environment. Therefore, the current review focuses on microbial community in the different habitats from the quorum sensing perspective. Firstly, the definition and classification of quorum sensing were simply introduced. Subsequently, the relationships between quorum sensing and microbial interactions were deeply explored. The latest progressives regarding the applications of quorum sensing in wastewater treatment, human health, food fermentation, and synthetic biology were summarized in detail. Finally, the bottlenecks and outlooks of quorum sensing driving microbial community were adequately discussed. To our knowledge, this current review is the first to reveal the driving force of microbial community from the quorum sensing perspective. Hopefully, this review provides a theoretical basis for developing effective and convenient approaches to control the microbial community with quorum sensing approaches.

Effects of biofilm and co-culture with Bacillus velezensis on the synthesis of esters in the strong flavor Baijiu.

Biofilm plays an important role in resisting the adverse environment, improving the taste and texture, and promoting the synthesis of flavor substances. However, to date, the findings on the effect of biofilm and dominating bacteria Bacillus on the ester synthesis in the Baijiu field have been largely lacked. Therefore, the objectives of the present study were to primarily isolate biofilm-producing microbes in the fermented grains, evaluate the stress tolerance capacity, and unveil the effect of biofilm and co-culture with Bacillus on the ester synthesis in the strong flavor Baijiu. Results indicated that after isolation and evaluation of stress-tolerance capacity, bacterial strain BG-5 and yeast strains YM-21 and YL-10 were demonstrated as mediate or strong biofilm-producing microbes and were identified as Bacillus velezensis, Saccharomycopsis fibuligera, and Zygosaccharomyces bailii, respectively. Solid phase microextraction/gas chromatography-mass spectrometer indicated that biofilm could enhance the diversity of esters while reduce the contents of ester. The scanning electron microscopy showed an inhibitory effect of B. velezensis on the growth of S. fibuligera, further restraining the production of esters. Taken together, both biofilm and B. velezensis influence the ester synthesis process. The present study is the first to reveal the biofilm-producing microorganisms in fermented grains and to preliminarily investigate the effect of biofilm on the ester synthesis in the Baijiu field.

Structural characterization of peach gum polysaccharide and its effects on the regulation of DSS-induced acute colitis.

The structure and the effect of polysaccharide from peach gum (DPG2) on ameliorating DSS-induced acute colitis in mice were investigated in the present study. The results showed that DPG2 was identified as an AG II arabinogalactan with the backbone of ß-D-(1 â†’ 6)-galactan, which consisted of mannose, glucuronic acid, galactose, xylose and arabinose with a molar ratio of 4.64:1.02:2.61:39.82:3.89:48.02. Moreover, DPG2 behaved as a flexible chain conformation with a coil-like structure with a molecular weight (Mw) of 5.21 × 105 g/mol. Furthermore, the worm-like chain model parameters for DPG2 were estimated as follows: ML = 379 nm-1, q = 0.74 nm and d = 0.82 nm. The results of the animal assay showed that the intake of DPG2 not only effectively improved the phenotypes of DSS-induced colitis in mice, but also significantly improved the oxidative stress status of mice, such as regulating NO content and T-SOD and MPO levels and repairing oxidative damage to the colonic mucosa. Moreover, DPG2 improved the inflammation of DSS-induced colitis in mice by inhibiting the secretion of the proinflammatory cytokines TNF-α, IFN-γ, IL-1ß, IL-6 and IL-17. Therefore, these results suggested that peach gum polysaccharide showed protective effects against colitis, and has great potential for the application of functional components in the food industry.

In Vitro Digestion and Fecal Fermentation of Peach Gum Polysaccharides with Different Molecular Weights and Their Impacts on Gut Microbiota.

In the present study, we investigated the in vitro digestion and fermentation characteristics of three peach gum polysaccharides (PGPs) of different molecular weights; i.e., AEPG2 (1.64 × 107 g/mol), DPG2 (5.21 × 105 g/mol), and LP100R (8.50 × 104 g/mol). We observed that PGPs were indigestible during the oral, gastrointestinal, and intestinal stages. However, they were utilized by the gut microbiota with utilization rates in the order of DPG2 > AEPG2 > LP100R. Furthermore, arabinose in PGPs was preferentially utilized by the gut microbiota followed by galactose and xylose. Fermentation of peach gum polysaccharides could significantly increase the production of short-chain fatty acids (SCFAs), especially n-butyric acid. In addition, PGPs with different molecular weights values were predominantly fermented by different bacterial species. AEPG2 and DPG2 were fermented by the Bacteroidetes bacteria Bacteroides, while the dominant n-butyrate-producing bacteria was Faecalibacterium. While the LP100R was fermented by Bacteroides, Parabacteroides, Phascolarctobacterium, Dialister, Lachnospiraceae, and Blautia, the dominant n-butyrate-producing bacteria was Megamonas. These results indicated that PGPs are potential prebiotics for the food industry.

Distribution and Quantification of Lactic Acid Enantiomers in Baijiu.

Enantiomers of lactic acid were investigated in Baijiu, including soy sauce aroma-type Baijiu (SSB), strong aroma-type Baijiu (STB), and light aroma-type Baijiu (LTB), via high-performance liquid chromatography with a chiral separation column. The natural concentration and enantiomeric distribution of lactic acid were studied, and their contribution to the flavor of Chinese Baijiu was evaluated based on recognition threshold. The results showed that there were significant differences in the content of lactic acid and the ratio of enantiomeric isomers among different aroma types and storage year. In SSB, the concentrations of D-lactic acid and L-lactic acid were higher, with the highest concentrations of 1985.58 ± 11.34 mg/L and 975.31 ± 14.03 mg/L, respectively. In STB, the highest concentrations of D-lactic acid and L-lactic acid were 1048.00 ± 11.46 mg/L and 939.83 ± 0.23 mg/L, respectively. In LTB, the highest concentrations of D-lactic acid and L-lactic acid were 760.90 ± 9.45 mg/L and 558.33 ± 3.06 mg/L, respectively. The average D/L enantiomeric ratios were 78:22 ± 16.16 and 80:20 ± 9.72 in the Commercial Baijiu products of SSB and STB, respectively. The average D/L enantiomeric ratio in LTB was 90:10 ± 6.08. D-lactic acid in JSHS vintage Baijiu showed a wave variation with aging, while L-lactic acid gradually increased during aging, and the average D/L enantiomeric ratio was 76:24 ± 4.26. The concentration of D-lactic acid in XJCT vintage Baijiu also showed a wave variation with aging, and the concentration of L-lactic acid tended to be stable during aging, with an average D/L enantiomeric ratio of 88:12 ± 2.80. The content of the two configurations of lactic acid in the LZLJ vintage Baijiu showed a decreasing trend during aging, with an average D/L enantiomeric ratio of 60:40 ± 11.99. The recognition threshold of D-lactic acid in 46% ethanol solution was 194.18 mg/L with sour taste; while the L-lactic acid was 98.19 mg/L with sour taste. The recognition threshold of L-lactic acid was about half that of D-lactic acid, indicating that L-lactic acid has a stronger sour taste. The taste activity values (TAVs) of D-lactic acid and L-lactic acid were greater than 1 in most of the Baijiu samples, and the TAV of D-lactic acid was greater than that of L-lactic acid. The study showed that the lactic acid enantiomers contributed to the taste perception of Baijiu in most of the samples, and D-lactic acid contributed more to the Baijiu taste than L-lactic acid.

AHL-mediated quorum sensing to regulate bacterial substance and energy metabolism: A review.

Substance and energy metabolism are the basis for all life activities and are largely regulated by cell-to-cell communication. Microbial cell-to-cell communication often occurs by releasing and receiving quorum sensing molecules (QSMs). QSMs are abundant and widely distributed in natural or artificial microbial communities, of which N-acyl homoserine lactones (AHLs), as a typical representative of QSMs, could strongly affect the physiological metabolism of microorganisms. Therefore, this review focuses on the role of AHL-mediated quorum sensing (AHL-QS) in the regulation of bacterial substance and energy metabolism. First, the typical molecular structures and general mechanism of the AHLs involved in this review were briefly introduced, and the findings regarding the regulatory mechanisms of AHLs in carbon metabolism (sugar uptake, Embden-Meyerhof-Parnas pathway, tricarboxylic acid cycle, hexose monophosphate pathway, amino acid and nucleotide metabolism and methane metabolism), nitrogen metabolism, sulfur metabolism and energy metabolism were discussed in detail. Finally, the regulation of AHL-QS in bacterial substance and energy metabolism was concluded, and the perspectives were highlighted. The progressive findings on the AHL-mediated QS involved in substance metabolism and energy metabolism are systematically and comprehensively summarized in this review. Thorough insight into the role of QS in metabolic processes is hopefully provided.

Effect of Yeast Fermentation on the Physicochemical Properties and Bioactivities of Polysaccharides of Dendrobium officinale.

Fermentation is an effective method for enhancing the biological activity of polysaccharides, but research on its effect on Dendrobium officinal polysaccharides is rare. In this study, the effects of mono-fermentation (Saccharomyces cerevisiae FBKL2.8022, Sc; Wickerhamomyces anomalous FBKL2.8023, Wa) and co-fermentation (Sc+Wa) on the physicochemical properties and bioactivity of Dendrobium officinal polysaccharides were investigated. Meanwhile, the polysaccharide (DOP) obtained from Dendrobium officinale was used as a control. Four homogeneous polysaccharides were obtained by isolation and purification and named DOSCP, DOWAP, DOSWP, and DOP. The results showed that DOSCP, DOWAP, DOSWP, and DOP consisted of mannose and glucose with ratios of 3.31:1, 5.56:1, 2.40:1, and 3.29:1, respectively. The molecular weights (Mws) of the four polysaccharides were 25.73 kDa, 15.01 kDa, 17.67 kDa, and 1268.21 kDa. The antioxidant activity of DOSCP, DOWAP, and DOSWP was better than that of DOP. Additionally, all four polysaccharides were able to reduce the inflammatory response of LPS-induced RAW 264.7 macrophages in the mice without a significant difference. Yeast fermentation significantly reduced the molecular weight and improved the antioxidant activity of Dendrobium officinale polysaccharides, indicating a potential way to improve its antioxidant activity.

Distribution and Quantification of 1,2-Propylene Glycol Enantiomers in Baijiu.

Enantiomers of 1,2-Propylene glycol (1,2-PG) were investigated in 64 commercial Chinese Baijiu including soy sauce aroma-type Baijiu (SSB), strong aroma-type Baijiu (STB), and light aroma-type Baijiu (LTB), via chiral gas chromatography (ß-cyclodextrin). The natural enantiomeric distribution and concentration of 1,2-PG in various baijiu were studied to evaluate whether the distribution and content of the two isomers of 1,2-PG were correlated with the aroma type and storage year. The results showed that 1,2-PG has a high enantiomeric ratio and the (S)-configuration predominated in SSB. The average S/R enantiomeric ratio of this compound in SSB was approximately 87:13 (±3.17), with an average concentration of 52.77 (±23.70) mg/L for the (S)-configuration and 8.72 (±3.63) mg/L for the (R)-enantiomer. The (R)-configuration was predominant in the STB, whereas neither (S) nor (R)-form of 1,2-PG were detected in LTB. The content of the two configurations of 1,2-PG in the JSHSJ vintage of SSB showed a wave variation, with an average S/R enantiomeric ratio of 89:11 (±1.15). The concentration of (R)-1,2-PG in XJCTJ vintage liquors showed an upward and then downward trend with aging time, with an overall downward trend, and the concentration of (S)-form showed a wavy change with an overall upward trend. Except for the LZLJ-2019 vintage where both (R) and (S)-1,2-PG were present, all other samples only existed (R)-form, and a decreasing trend of (R)-enantiomer with aging time was observed. The enantiomeric ratio of 1,2-PG might be one of the potential markers for adulteration control of Baijiu as industrial 1,2-PG usually presented in the racemic mixture. Sensory analysis revealed olfactory thresholds of 4.66 mg/L and 23.92 mg/L for the (R)- and (S)-configurations in pure water respectively. GC-O showed both enantiomers exhibited different aromatic nuances.

Hsa_circ_0000231 knockdown inhibits the glycolysis and progression of colorectal cancer cells by regulating miR-502-5p/MYO6 axis.

BACKGROUND: Colorectal cancer (CRC) poses a heavy threat to human health owing to its high incidence and mortality. Circular RNAs (circRNAs) were investigated to participate in the progression of CRC, whereas there was no revenant data on the CRC process regulated by hsa_circ_0000231. This study aimed to explore the effects of hsa_circ_0000231 on CRC progression and underneath regulatory mechanism. METHODS: The expression levels of hsa_circ_0000231, miR-502-5p, and Myosin VI (MYO6) mRNA were detected by quantitative real time polymerase chain reaction (qRT-PCR). Western blot was employed to determine the protein expression levels of MYO6 and proliferating cell nuclear antigen (PCNA). The effects of hsa_circ_0000231 on cell proliferation, apoptosis, migration, and invasive in CRC were determined by cell counting kit-8 proliferation (CCK-8) and colony formation assays, flow cytometry analysis, wound-healing assay, and transwell invasion assay, respectively. Glucose uptake and lactate production were severally illustrated by glucose assay kit and lactate assay kit. The relationship between miR-502-5p and hsa_circ_0000231 or MYO6 was predicted by circular RNA interactome or targetScan online databases, and identified by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. In vivo tumor formation assay was carried out to determine the effects of hsa_circ_0000231 knockdown on tumor growth in vivo. RESULTS: Hsa_circ_0000231 expression was dramatically upregulated while miR-502-5p was obviously downregulated in CRC tissues and cells compared with control groups. Hsa_circ_0000231 knockdown repressed the expression levels of MYO6 and PCNA protein. Functionally, hsa_circ_0000231 knockdown repressed cell glycolysis, proliferation, migration and invasion, and induced cell apoptosis, whereas these effects were decreased by miR-502-5p inhibitor. Mechanistically, hsa_circ_0000231 acted as a sponge of miR-502-5p and miR-502-5p bound to MYO6. Furthermore, hsa_circ_0000231 knockdown decreased tumor volume and weight of CRC in vivo. CONCLUSION: Hsa_circ_0000231 knockdown inhibited CRC progression and glycolysis by downregulating MYO6 expression through sponging miR-502-5p, which might provide a theoretical basis in further studying circ_0000231-directed therapy in CRC.

Traumatic brachial plexus injury: a study of 510 surgical cases from multicenter services in Guangxi, China.

BACKGROUND: Traumatic brachial plexus injuries are severe lesions, and the incidence of these injuries has been increasing in recent years. METHODS: The clinical data of 510 operated patients with brachial plexus injury recruited from 74 hospitals in Guangxi from 2004 to 2016 were retrospectively studied. RESULTS: Our study included 447 males and 63 females, with an average age of 29.04 years. Traffic accidents were the most common cause of injury (64.71%), especially motorcycle accidents. Closed injuries accounted for 88.24% of cases, and 83.53% of patients had associated injuries, the most common of which were fractures (76.27%). The preoperative predictive value of root injury of MRI and CT was 74.71% and 71.28%, respectively. 44.71% of patients underwent an initial operation within 6 months after the trauma. Regarding the surgery, neurolysis alone, brachial plexus reconstruction, and free functioning gracilis graft accounted for 16.67%, 75.50%, and 4.51%, respectively. A total of 415 patients were followed up with an average time of 47.95 (25-68) months, and anxiety or depression were found among 81.20% of them. Two hundred seventy-six patients suffered from nerve pain, with mild pain present in 67.03% of patients. Additionally, 347 patients were followed up for more than 3 years, 76.81% of patients with C5-C6 injury recovery to useful function, and the procedure of neurolysis alone demonstrated the best efficacy (79.45%). CONCLUSIONS: Brachial plexus injury is still a challenging trauma for surgeons, and traffic accidents are the dominant cause. Timely and effective surgery is important for functional limb recovery.

[Application of MR arthrography for diagnosis of femoral acetabular impingement syndrome].

Femora acetabular impingement (FAI) is thought as the major reason leds to hip osteoarthritis. FAI results to destruction of the arthrodial cartilage. Prognoses of hip osteoarthritis is affected by the degree of arthrodial cartilage destruction. The hip osteoarthritis could be prevented if FAI is diagnosed and treated in earlier period. How can we diagnose FAI in earlier period? Recent studies showed that MRI was the best way for FAI diagnosis. It has higher resolution and signal-noise ratio. Cartilage and gleniod labrum of hip could be shown by MRI. The paper reviewed the standard and difficulties of diagnosis about FAI. High magnet MRI maybe is one way to solve the problems.

Methanol metabolism in the Asian corn borer, Ostrinia furnacalis (Guenée) (Lepidoptera: Pyralidae).

Plants produce and release large quantities of methanol, especially when attacked by herbivores. It seems that the herbivores may suffer from methanol intoxication. Here we reported the tolerance to and the metabolism of methanol by Ostrinia furnacalis third-instar larvae. When larvae were exposed to dietary methanol, formaldehyde and formic acid for 72h, the estimated LC(50) value was 28, 40 and 29 mg/g diet, respectively. Toxicity of methanol was enhanced by 4-methylpyrazole, 3-amino-1,2,4-triazole and piperonyl butoxide, and toxicity of formaldehyde was increased by 3-amino-1,2,4-triazole and piperonyl butoxide. However, triphenyl phosphate had little synergistic effects on both methanol and formaldehyde. These data indicate that alcohol dehydrogenase, and probably catalase and cytochrome P450 monooxygenase oxidize methanol to formaldehyde, catalase and cytochrome P450 monooxygenase catalyze formaldehyde to formic acid, water and carbon dioxide, and carboxylesterase may have a minor effect. Several fatty acid methyl esters (FAMEs) were identified from extracts of the frass of larvae which had been exposed to a methanol-contained diet, in contrast to those on a methanol-free artificial diet. In vitro tests revealed that a crude enzyme solution from the larvae could synthesize FAMEs from corresponding fatty acids and methanol. In addition, dietary methanol induced higher esterase activities in the first-, second- and third-instar larvae. These findings demonstrate that both oxidative metabolism and non-oxidative metabolism are partially responsible for methanol elimination in O. furnacalis larvae.