Recurrence Rate and Influencing Factors of Helicobacter Pylori Infection After Successful Eradication in Southern Coastal China.

Purpose: Recurrence rate of Helicobacter pylori (H. pylori) infection after successful eradication have gained attention. This study was to assess the recurrence rate of H. pylori infection after successful eradication in the southern coastal provinces of China and to analyze its factors. Patients and Methods: 975 patients with upper gastrointestinal symptoms who were diagnosed with H. pylori infection using the 13C or 14C-urea breath test (UBT) underwent eradication treatment between August 2021 and December 2022. After eight to twelve weeks, repeat UBT was performed. Besides, 824 patients with successful eradication underwent a repeat UBT by completing questionnaires after a year. The 1-year recurrence rate was calculated, and the differences were analyzed based on baseline data, sociological characteristics, and lifestyle. Results: A total of 734 patients completed the 1-year follow-up, out of which 26 (3.5%) patients experienced a recurrence of H. pylori infection. Exposure to other individuals infected with H. pylori (χ2=12.852, P<0.001), poor hygiene conditions at dining out places (χ2=6.839, P=0.009), frequent dining out (χ2=24.315, P<0.001), smoking (χ2=7.510, P=0.006), consumption of non-purified water (χ2=16.437, P<0.001), consumption of pickled foods (χ2=5.682, P=0.017), irregular meal patterns (χ2=16.877, P<0.001) and age (χ2=9.195, P=0.010) were significant factors for H. pylori infection recurrence. Exposure to other individuals infected with H. pylori, poor hygiene conditions at dining out places, consumption of non-purified water, frequent dining out and irregular meal patterns were independent risk factors (P=0.022, 0.016, 0.002, <0.001, <0.001; 95% CI 0.146-0.861, 0.121-0.806, 1.715-10.845, 0.085-0.521, 2.291-14.556). Conclusion: The one-year recurrence rate of H. pylori infection post-eradication in the southern coastal provinces of China is 3.5%. Contacting with infected individuals, poor hygiene in dining places, consumption of non-purified water, frequent dining out, and irregular meal patterns were identified as significant independent factors influencing H. pylori recurrence.

Prevalence, types, and risk factors of functional gastrointestinal diseases in Hainan Province, China.

To investigate the prevalence, types, and risk factors of functional gastrointestinal diseases (FGIDs) in Hainan Province, China, in order to provide insights for future prevention and treatment strategies. A questionnaire survey was conducted from July 2022 to May 2023, using stratified sampling to sample local residents in five cities (20 townships) in Hainan Province. Out of 2057 local residents surveyed, 659 individuals (32.0%) reported experiencing at least one FGID. The most prevalent FGIDs were functional dyspepsia (FD) (10.7%), functional constipation (FC) (9.3%), irritable bowel syndrome (IBS) (6.8%), functional bloating (2.2%), belching disorder (2.2%), functional diarrhea (FDr) (1.5%), functional heartburn (1.5%), and fecal incontinence (0.98%). The study revealed significant associations between FGIDs and factors such as age, sleep quality, anxiety, smoking, alcohol consumption, and the consumption of pickled food (P < 0.05). Older age, poor sleep quality, anxiety, and the consumption of pickled food were identified as independent risk factors for the prevalence of FGIDs (P < 0.05). In Hainan Province, the overall prevalence of FGIDs was found to be 32.0%, with higher prevalences of FC and FD. Older age, poor sleep quality, anxiety, and the consumption of pickled food were identified as risk factors for FGIDs.

Succession of microbial community of the pit mud under the impact of Daqu of Nongxiang Baijiu.

Complex microbiomes of pit mud play significant roles in imbuing flavors and qualities of Nongxiang Baijiu during fermentation. However, pit mud microbial enrichment and succession is a long process that is also accompanied by aging. Development of high-quality artificial pit mud becomes an urgent problem. In this study, a new medium based on space (TK) Daqu was used to effectively enrich the dominant microorganisms in pit mud. The results showed that Caproiciproducens was the most preponderance in the cultures unadded Daqu, whereas Clostridium sensu stricto 12 was the most preponderance, followed by Caproiciproducens in the enrichment cultures added TK Daqu. It is worth noting that TK Daqu balanced the relative abundance of Caproiciproducens and Clostridium sensu stricto 12 in 100-year pit mud culture (S100), which was more conducive to the increase of methanogens. PICRUSt2 prediction results showed that hydrogenotrophic methanogens could promote the synthesis of caproic acid by using the product H2 as the metabolic substrate and increased significantly in the pit mud enrichment cultures with TK Daqu. The increase of lactate dehydrogenase (EC 1.1.1.27) content in S100 contributed to the degradation of lactic acid and the increase of caproic acid. Adding TK Daqu enrichment cultures is more conducive to the enrichment and metabolic balance of pit mud microorganisms.

Effects of Daqu properties on the microbial community and their metabolites in fermented grains in Baijiu fermentation system.

Daqu is the natural starter for Nong-flavor Baijiu brewing. The effects of Daqu properties on the microbial community succession and their metabolites in fermented grains (FG) during Baijiu brewing were determined. These results showed that the effect of Daqu on the bacterial communities was stronger than that of the fungal communities. Compared with the conventional Daqu (DZ), Taikong (TK), and Qianghua (QH), Daqu significantly enhanced the content of volatile metabolites (especially esters) and ethanol when they were used, respectively, for FG fermentation. In the second round of fermentation, the relative abundance of Lactobacillus decreased, the content of lactic acid decreased, and that of caproic acid increased. In particular, the abundance of Lactobacillus was also reduced by 20% in FGs of the second round when TK Daqu was used than that in the respective first round. Partial least squares structural equation model analysis also showed that physicochemical parameters and Daqu properties significantly affected FG community structure and metabolism. This study provides a theoretical basis for further study on the effect of high-quality Daqu on the quality of fresh Baijiu and lays an important theoretical foundation for the stabilization of the Baijiu fermentation system based on Daqu.

Effects of Different Daqu on Microbial Community Domestication and Metabolites in Nongxiang Baijiu Brewing Microecosystem.

The quality and yield of the fresh Baijiu mainly depend on the activity of pit mud (PM) and the quality of Daqu. However, the cultivation of PM is a long-term process, and high-quality Daqu can change the community structure of fermented grain (FG) and accelerate the evolution of PM communities. The present research aimed to investigate the four different types of Daqu on the FG-fermenting microbial community structure and metabolites and their interphase interactions with PM. These results show that Kroppenstedtia in the bacterial community of Taikong Daqu (TK) was positively correlated with ethyl caproate, which significantly increased the content of FG volatile metabolites, especially lipid components, and facilitated the accelerated evolution of Methanobacteriales and Methanosarcinales in PM. Bacillus has a high relative abundance in Qianghua Daqu (QH), which shows obvious advantages to improving the alcoholic strength of FG and contributing to increasing the abundance of Methanomicrobiales in PM. Qianghua and traditional-mixed Daqu (HH) have a similar bacterial composition to QH and a similar fungal composition to traditional Daqu (DZ), and thus also showed the advantage of increased yield, but the volatile flavor metabolites produced were not as dominant as DZ. ß-diversity analysis showed that in TK fermentation systems, FG is more likely to domesticate the structure of PM microorganisms. These results indicated that the interaction between microbial communities in Baijiu fermentation niches was significantly influenced by different Daqu. It can not only enhance the key volatiles in FG but also accelerate the evolving direction of the community in PM. Daqu fortified by functional genera or microbiota can evolve a community structure more suitable for Baijiu fermentation. The microbiota composition and interaction between the communities in both Daqu and PM significantly impacts the yield and quality of the base liquor.

Exploring the response patterns of strong-flavor baijiu brewing microecosystem to fortified Daqu under different pit ages.

The fermentation of strong-flavor baijiu depends largely on the evolution of the microbial community that originated from Daqu and pit mud (PM). Applying fortified Daqu (FD) has been proven to be an effective strategy to improve the quality and yield of baijiu. However, it is unclear what the effects of FD on the liquor brewing microecosystem under different pit ages because of the temporal heterogeneity of the PM community. Taking 2-year (new) and 40-year (aged) pits as the objects, the influence of FD on the metabolic profile, physicochemical parameters, and community diversity in Zaopei and PM was investigated by polyphase detecting approaches. Present results showed that the metabolic profiles of Zaopei were significantly improved by FD, whereas those of PM were mainly dependent on pit age. Aspergillus, Caproiciproducens, and Methanosarcina were more abundant in the aged pit, while Kazachstania, Lactobacillus, and Sphingomonas dominated in the new pit, whether in Zaopei or in PM. The interaction relationships among the communities were also altered by FD, and the co-occurrence network, especially the increased links between archaea and bacteria in the new pit. Notably, this interaction in the aged pit distinctly affected the hexanoic acid content based on the Mantel test. The results of PICRUSt2 analysis inferred that FD perhaps improved the interspecies hydrogen transfer in the new pit and increased the carbon flow of hexanoic acid production during chain elongation in the aged pit. These results provide new insights into the production of high-quality strong-flavor baijiu and the aging of PM.

Real-time monitoring of electroreduction and labelling of disulfide-bonded peptides and proteins by mass spectrometry.

The accurate determination of disulfide bonds for protein identification is in high demand. In this study, a simple electrochemical-mass spectrometry (EC-MS) method that possesses advantages of real-time information, simultaneous disulfide bond electroreduction and tagging was developed. In this EC-MS, an ITO glass corner functions as a counter electrode and spray system, and allows the direct sampling of the droplet-scale reacting solution in real-time. The application of this method was successfully demonstrated by electrochemical reduction of oxidized glutathione (GSSG) with one disulfide bond as well as insulin with multiple disulfide bonds. The preferred electroreduction of intermolecular-bonded disulfides for insulin has been observed and the intramolecular bond was not favored. Moreover, simultaneously tagging the formed thiol residues from electroreduction of GSSG using electrogenerated intermediates such as dopamine orthoquinone (DQ) and benzoquinone (Q) was performed. A proof-of-concept was also demonstrated with a large molecule, ß-lactoglobulin A. The relationship between signal strength and operating parameters was also studied. This method successfully detected the reduction reaction of the disulfide bond in the polypeptide and protein. The detection limit (S/N ≥ 3) is 0.398 µg mL-1. These results suggest that this EC-MS platform can count cysteine moieties in proteins using a single drop of sample and in real-time and is promising for protein identification experiments.

Identification and characterization of a novel casein anticoagulant peptide derived from in vivo digestion.

Casein (CN) has been regarded as an excellent protein source for preparing bioactive peptides. In this study, the casein peptides released in the mouse gastrointestinal tract were evaluated. The 10-week-old mouse was orally administered with 5 mg casein. After 0.5 h, the peptides in the stomach and small intestine of the mouse were extracted and analyzed by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS). A total of 343 peptides were identified, and 98, 36, 181 and 28 peptides were derived from αs1-, αs2-, ß- and κ-CN respectively. Then, in silico methods were adopted to predict the potential anticoagulant peptide, including PeptideRanker, Innovagen. A novel anticoagulant peptide, AVPYPQR (ß-CN, fragment 177-183), was screened and its anticoagulant activity was verified. In vitro anticoagulant assay showed that the peptide AVPYPQR can observably prolong activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT), which indicated that the peptide AVPYPQR exerts its anticoagulant activity in the intrinsic, extrinsic, and common pathways. Meanwhile, the cell viability of this peptide was estimated on the human umbilical vein endothelial cells (HUVECs). The physicochemical characteristics of this peptide have been assayed by PepDraw and ExPASy-ProtParam. The study indicated that casein could be a valuable source for preparing bioactive peptides by gastrointestinal (GI) tract digestion.

Identification and In Silico Prediction of Anticoagulant Peptides from the Enzymatic Hydrolysates of Mytilus edulis Proteins.

Mytilus edulis is a typical marine bivalve mollusk. Many kinds of bioactive components with nutritional and pharmaceutical activities in Mytilus edulis were reported. In this study, eight different parts of Mytilus edulis tissues, i.e., the foot, byssus, pedal retractor muscle, mantle, gill, adductor muscle, viscera, and other parts, were separated and the proteins from these tissues were prepared. A total of 277 unique peptides from the hydrolysates of different proteins were identified by UPLC-Q-TOF-MS/MS, and the molecular weight distribution of the peptides in different tissues was investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The bioactivity of the peptides was predicted through the Peptide Ranker database and molecular docking. Moreover, the peptides from the adductor muscle were chosen to do the active validation of anticoagulant activity. The active mechanism of three peptides from the adductor muscle, VQQELEDAEERADSAEGSLQK, RMEADIAAMQSDLDDALNGQR, and AAFLLGVNSNDLLK, were analyzed by Discovery Studio 2017, which also explained the anticoagulant activity of the hydrolysates of proteins from adductor muscle. This study optimized a screening and identification method of bioactive peptides from enzymatic hydrolysates of different tissues in Mytilus edulis.

Analysis and Evaluation of the Inhibitory Mechanism of a Novel Angiotensin-I-Converting Enzyme Inhibitory Peptide Derived from Casein Hydrolysate.

Casein hydrolysates exert various biological activities, and the responsible functional peptides are being identified from them continuously. In this study, the tryptic casein hydrolysate was fractionated by an ultrafiltration membrane (3 kDa), and the peptides were identified by capillary electrophoresis-quadrupole-time-of-flight-tandem mass spectrometry. Meanwhile, in silico methods were used to analyze the toxicity, solubility, stability, and affinity between the peptides and angiotensin-I-converting enzyme (ACE). Finally, a new angiotensin-I-converting enzyme inhibitory (ACEI) peptide, EKVNELSK, derived from αs1-casein (fragment 35-42) was screened. The half maximal inhibitory concentration value of the peptide is 5.998 mM, which was determined by a high-performance liquid chromatography method. The Lineweaver-Burk plot indicated that this peptide is a mixed-type inhibitor against ACE. Moreover, Discovery Studio 2017 R2 software was adopted to perform molecular docking to propose the potential mechanisms underlying the ACEI activity of the peptide. These results indicated that EKVNELSK is a new ACEI peptide identified from casein hydrolysate.

Beneficial effects of polysaccharides on the solubility of Mytilus edulis enzymatic hydrolysates.

The low stability of proteins and peptides in liquid systems restricts the development of enzymatic hydrolysate. In this study, a variety of protein hydrolysates from Mytilus edulis (PHM) were prepared by enzymatic hydrolysis. The effects of four kinds of polysaccharides, CMC-Na, xanthan gum, ß-cyclodextrin, and Z-trim, on the stability of PHM were investigated by comparing the protein precipitation rate, particle size, zeta potential, microstructure, and fluorescence spectra. Results showed that the aqueous mixture enriched with proteins and peptides was stabilized by the addition of 1 mg/mL xanthan gum at pH 8, and it significantly prevented protein deposition. Particle size and zeta potential measurements confirmed the beneficial effects of xanthan gum on the stability of PHM. This study provides some theoretical references for the research and development of proteins from M. edulis.

Identification and Antithrombotic Activity of Peptides from Blue Mussel (Mytilus edulis) Protein.

The blue mussel (Mytilus edulis) reportedly contains many bioactive components of nutritional value. Water-, salt- and acid-soluble M. edulis protein fractions were obtained and the proteins were trypsinized. The resultant peptides were analyzed by ultra-performance liquid chromatography quadrupole time of flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS). 387 unique peptides were identified that matched 81 precursor proteins. Molecular mass distributions of the proteins and peptides were analyzed by sodium dodecyl sulfate-polyacryl amide gel electrophoresis (SDS-PAGE). The differences between the three protein samples were studied by Venn diagram of peptide and protein compositions. Toxicity, allergic and antithrombotic activity of peptides was predicted using database website and molecular docking respectively. The antithrombotic activity of enzymatic hydrolysate from water-, salt- and acid-soluble M. edulis protein were 40.17%, 85.74%, 82.00% at 5 mg/mL, respectively. Active mechanism of antithrombotic peptide (ELEDSLDSER) was also research about amino acid binding sites and interaction, simultaneously.