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Parent amido complexes are crucial intermediates in ammonia-based transformations. We report a well-defined ferric ammine system [Cp*Fe(1,2-Ph

Background Tendon-ligament injuries (TLIs), including Achilles tendinopathy, cruciate ligament injury, tennis elbow, rotator cuff injury, patellar tendinopathy, and tibial tendinopathy, are common musculoskeletal soft injuries during physical activity. Matrix metalloproteinase-3 (MMP-3) gene polymorphisms have been implicated in the etiology of TLIs in several genetic association studies with inconsistent results. The purpose of this study was to collect and synthesize the current evidences on the association of MMP-3 polymorphisms and TLIs. Methods The search was conducted using PubMed, Web of Science, EMBASE, Cochrane Library, CNKI and Wanfang databases, prior to July, 2021. Newcastle Ottawa Scale was used to appraise the study quality. Strengths of association were represented by odds ratios (ORs) and 95% confidence intervals (95% CIs). Results Thirteen studies with 2871 cases and 4497 controls met the eligibility criteria, and each study was in high quality. The overall analyzes suggested rs3025058 was associated with an increased TLIs risk (5A vs. 6A, OR = 1.20, 95% CI 1.03–1.40, P = 0.020). However, the association was not found for rs679620, rs591058, and rs650108 polymorphisms. Subgroup analysis by injury type suggested that rs679620 polymorphism was associated with a reduced risk to Achilles tendon rupture (AA + AG vs. GG, OR = 0.46, 95% CI 0.25–0.87, P = 0.020), and rs3025058 was associated with an elevated risk to anterior cruciate ligament injury (5A5A + 5A6A vs. 6A6A, OR = 1.46, 95% CI 1.03–2.06, P = 0.030). When stratified by ethnicity, the findings indicated that rs3025058 polymorphism was associated with an increased TLIs risk among Caucasians (5A6A vs. 6A6A, OR = 1.55, 95% CI 1.09–2.42, P = 0.020) and Brazilians (5A5A vs. 5A6A + 6A6A, OR = 2.80, 95% CI 1.44–5.45, P = 0.002). Conclusion Findings of this study suggest that rs679620 polymorphism is associated with a reduced Achilles tendon rupture risk, and rs3025058 polymorphism contributes to an increased TLIs risk in Caucasians and Brazilians. However, rs591058 and rs650108 polymorphisms do not show any association with TLIs.

To improve the aroma profile of beer by using metabolic engineering to increase the availability of cytosolic NADH in lager yeast. To alter NADH levels in lager yeast, the native FDH1 (YOR388C) encoding NAD+-dependent formate dehydrogenase was overexpressed in the yeast strain M14, yielding strain M-FDH1. This led to a simultaneous increase of NADH availability and NADH/NAD+ ratio in the M-FDH1 strain during fermentation. At the end of the main fermentation period, ethanol production by strain M-FDH1 was decreased by 13.2%, while glycerol production was enhanced by 129.4%, compared to the parental strain respectively. The production of esters and fusel alcohols by strains M14 and M-FDH1 was similar. By contrast, strain M-FDH1 generally produced less organic acids and off-flavor components than strain M14, improving the beer aroma. Increased NADH availability led to rerouting of the carbon flux toward NADH-consuming pathways and accelerated the NADH-dependent reducing reactions in yeast, greatly impacting the formation of aroma compounds and improving the beer aroma.

BACKGROUND: Holmium lasers have been used to treat bladder stones and achieve good therapeutic effects, but its efficacy remains to be explored. METHODS: The PubMed, Embase, Medline, Ovid, Springer, and Web of Sciences databases were searched from their establishment to December 31, 2020. Studies of randomized control trials (RCTs) examining the treatment of vesical calculi by holmium laser lithotripsy were identified. The Cochrane Handbook for Systematic Reviews of Intervention 5.0.2 was used to assess risk bias, and Rev Man5.3 was used to conduct the meta-analysis. RESULTS: A total of 10 studies, comprising 1,642 subjects, were included. The meta-analysis results showed that the surgery time and the hospitalization time of patients treated with holmium laser lithotripsy decreased, and the calculus removal rate increased. The experimental group had a lower incidence of adverse reactions, such as postoperative urinary tract infection, mucosal damage, vesical perforation, residual calculi, hematuria, and abdominal pain than the control group; however, no notable difference was observed in relation to surgery time, hospital stay, the calculus removal rate, mucosal damage, bladder perforation, hematuria, and abdominal pain between the 2 groups. DISCUSSION: Holmium laser lithotripsy significantly reduced the hospitalization time of patients treated with holmium laser lithotripsy and elevated the removal rate.

Over the past years, archaeobotanical studies have clarified much of the process of dispersal and adaptation of crops across Asia. However, the development of farming systems that could function in the high-altitude environments of Tibet requires more in-depth consideration. In this article, we present the results of the systematic archaeobotanical investigation at Karuo, a third millennium BC site in eastern Tibet. We argue that millet cultivation was possibly practiced at the site and that it was likely an important aspect of the economy from 2700 to 2100 cal. BC. The role of millet in the cultivation system might have declined after the mid-second millennium BC, during which time wheat—a grain originating in southwest Asia—appeared at the site. In addition to farming, evidence of foraging, hunting, and fishing are present suggesting a diverse subsistence strategy. The diversification of human diets may have contributed to the long-term occupation of the site. Taking a broad regional perspective into account, the diverse spectrum of subsistence strategy engaged by Karuo people provides new insights into the understanding of early lifeways on the Tibetan Plateau. Introduction Karuo site Materials and methods Results - Plant remains - Chronology of the site Discussion - Millet - Wheat and barley - Other potential food resources - Subsistence strategy Conclusion

In this work, a β-cyclodextrin functional vinyl monomer was synthesized and the common moiety of five amanita toxins was used as the template for preparing molecularly imprinted polymers (MIPs). Chemical calculation was used to evaluate and describe the binding interactions between the template and the functional monomer. The preparation conditions were optimized and the resultant MIPs were characterized and employed as solid-phase extraction (SPE) sorbents. The SPE conditions including the amount of sorbent, extraction solution, and eluting solution were also optimized for the enrichment of the five toxins. Using an ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS), detection limits ranging from 0.34–0.42 µg/L, 0.16–0.33 µg/L, and 0.035–0.056 µg/kg were achieved for the five toxins in serum, urine and liver samples, respectively. The proposed method was further applied to the determination of the amanita toxins in suspected samples and showed great potential in the diagnosis of mushroom poisoning.

Serial repitching of beer brewer’s yeast plays an important role in the beer industry as an ineluctable economic factor. In this study, the viability and vitality changes, as well as strains’ anti-autolytic abilities during serial beer fermentation with typical ale and lager yeast strains, were investigated. While measuring the survival rate of yeast cells is not sufficient for evaluating and predicting the yeast fermentation capacity, physiological status determination of brewer’s yeast reflects the vitality and quality of yeast in serial beer fermentations. Accumulation of reactive oxygen species in yeast causes cell damage, leading to a decline in cell vitality and viability. Aged yeast cells, after several repitchings, can result in leakage of intracellular compounds into the fermented liquor. The lager yeast (Pilsner) examined, which harbors the partial genome from S. eubayanus, showed better robustness and higher activity than the ale yeast strain M79 examined, during serial fermentation. A holistic approach, including more indicators, should be applied in evaluating the fermentation performance of brewer’s yeast.

Acetaldehyde is synthesized by yeast during the main fermentation period of beer production, which causes an unpleasant off-flavor. Therefore, there has been extensive effort toward reducing acetaldehyde to obtain a beer product with better flavor and anti-staling ability. In this study, we discovered that acetaldehyde production in beer brewing is closely related with the intracellular NADH equivalent regulated by the citric acid cycle. However, there was no significant relationship between acetaldehyde production and amino acid metabolism. A reverse engineering strategy to increase the intracellular NADH/NAD+ ratio reduced the final acetaldehyde production level, and vice versa. This work offers new insight into acetaldehyde metabolism and further provides efficient strategies for reducing acetaldehyde production by the regulating the intracellular NADH/NAD+ ratio through cofactor engineering.

Saccharomyces cerevisiae strains with favorable characteristics are preferred for application in industries. However, the current ability to reprogram a yeast cell on the genome scale is limited due to the complexity of yeast ploids. In this study, a method named genome replication engineering-assisted continuous evolution (GREACE) was proved efficient in engineering S. cerevisiae with different ploids. Through iterative cycles of culture coupled with selection, GREACE could continuously improve the target traits of yeast by accumulating beneficial genetic modification in genome. The application of GREACE greatly improved the tolerance of yeast against acetic acid compared with their parent strain. This method could also be employed to improve yeast aroma profile and the phenotype could be stably inherited to the offspring. Therefore, GREACE method was efficient in S. cerevisiae engineering and it could be further used to evolve yeast with other specific characteristics.

The role of proteins, especially protein Z, on beer foam stability was studied. The results showed that both positive and negative proteins were enriched in beer foam. Contrary to previous results, proteins with lower surface hydrophobicity were preferred for beer foam stability. Among all proteins, protein Z was the most prevalent protein in beer foam and could be accurately measured using an enzyme linked immunosorbent assay. The quantity of protein Z was found to be positively correlated with beer foam stability. The addition of purified protein Z from barley (Hordeum vulgare) malt into the finished beer could enhance the beer foam stability. Therefore, proteins with lower surface hydrophobicity might be beneficial for beer foam stability, especially protein Z.

β-Amylase is of important biotechnological aid in maltose syrup production. In this study, the extraction condition of β-amylase from brewer's malt and the optimal dosage of β-amylase in maltose syrup production were optimized using response surface methodology and uniform design method. The optimal extraction condition of β-amylase from brewer's malt was composed of 1:17 (g/v) material/liquid ratio, 44°C extraction temperature, pH 6.4 buffer pH, 2.3 H extraction time, and 1.64 g L-1 NaSO3 dosage with a predicted β-amylase activity of 1,290.99 U g-1 , which was close to the experimental β-amylase activity of 1,230.22 U g-1 . The optimal dosages of β-amylase used in maltose syrup production were 455.67 U g-1 starch and its application in maltose syrup production led to a 68.37% maltose content in maltose syrup, which was 11.2% and 28.9% higher than those using β-amylases from soybean and microbe (P

This study aimed to isolate and identify the spoilage microbes which could produce gas in fermented broad bean paste and to provide an effective method to restrain their growth in media. The gas-producing spoilage microbe was isolated in anaerobic condition and identified as Bacillus licheniformis FHYM 8. B. licheniformis FHYM 8 was resistant to high temperature, low pH and high salinity condition since it could survive after treatment at 100 °C for 10 min and when the pH value was as low as pH3.8. The inhibitory salinity for B. licheniformis FHYM 8 was 15% in aerobic condition while 11% of salinity could completely inhibit its growth in anaerobic condition. Interestingly, B. licheniformis FHYM 8 showed the ability to produce gas when the broad bean paste was sterilized at 66 °C while no gas was produced when B. licheniformis FHYM 8 was inoculated in broad bean paste after the heat treatment process, indicating that heat treatment was the necessary step for B. licheniformis FHYM 8 to produce CO 2 in broad bean paste. The inhibition analysis showed that nisin with a minimal inhibitory concentration of 0.02 mg mL −1 was efficient in inhibiting the growth of B. licheniformis FHYM 8 in MRS media when the salinity was 8%. This will provide guidance to broad bean paste manufacturers to further adopt efficient strategies to inhibit the growth of gas-producing microbe in broad bean paste.

1,3-1,4-β-glucanase was an important biotechnological aid in the brewing industry. In a previous research, a Bacillus BglTO mutant (BglTO) with high tolerance towards high temperature and low-pH conditions was constructed and expressed in Escherichia coli. However, E. coli was not a suitable host for enzyme production in food industry. Therefore, the present work aimed to achieve the high-level expression of BglTO in Bacillus subtilis WB600 and to test its effect in Congress mashing. The β-glucanase mutant was successfully expressed in B. subtilis WB600 and favorable plasmid segregation and structural stability were observed. The maximal extracellular activity of β-glucanase in recombinant B. subtilis WB600 reached 4840.4 U mL−1 after cultivation condition optimization, which was 1.94-fold higher than that before optimization. The fermentation capacity of recombinant B. subtilis reached 242.02 U mL−1 h−1, which was the highest among all reported β-glucanases. The addition of BglTO in Congress mashing significantly reduced the filtration time and viscosity of mash by 29.7% and 12.3%, respectively, which was superior to two commercial enzymes. These favorable properties indicated that B. subtilis WB600 was a suitable host for production of BglTO, which was promising for application in the brewing industry.

The aim of this study was to discuss the functions of FKS family genes which encode β-1, 3-glucan synthase regarding the viability and autolysis of yeast strain. Loss of FKS1 gene severely influences the viability and anti-autolytic ability of yeast. Mutation of FKS1 and FKS2 genes led to cell reconstruction, resulting in a sharp shrinkage of cell volume and decreased stress resistance, viability, and anti-autolytic ability. Deletion of FKS3 gene did not clearly influence the synthesis of β-1, 3-glucan of yeast but increased the strain's stress resistance, viability, and anti-autolytic ability. It is suggested that FKS3 would be the potential target for improving the stress resistance of yeast. The results revealed the relationship among FKS family genes and demonstrated their functions on yeast cell wall construction and anti-autolytic ability.

This study aimed to elaborate the effect of N-glycosylation and glycation of protein Z4 from barley malt and recombinant Pichia pastoris on beer foam stability. The malt protein Z4 and recombinant protein Z4 showed similar N-glycosylation patterns while recombinant protein Z4 was glycosylated at a higher degree. In the simulated mashing and boiling, malt protein Z4 and deglycosylated malt protein Z4 preferred to glycate with glucose and maltose while recombinant protein Z4 and deglycosylated recombinant protein Z4 showed preference towards fructose. The addition of protein Z4 and protein Z4-saccharide complexes in finished beer showed that the addition of glycosylated protein Z4 only slightly enhanced the beer foam stability while the addition of glycated protein Z4 and protein Z4 with both glycation and glycosylation could significantly increase the beer foam stability. Therefore, glycation instead of N-glycosylation of protein Z4 played important roles in maintaining beer foam stability.

A novel ion imprinted mesoporous SBA-15 adsorbent was fabricated via one-pot synthesis at mild pH by using Cd2+ as template and 3-mercaptopropyltriethoxysilane as functional monomer for removal of Cd2+ from water. The resultant Cd2+ imprinted mesoporous silica (CdIMS) exhibited a highly ordered hexagonal inner structure identified using small angle X-ray diffraction (SAXD) and transmission electron microscope (TEM). The CdIMS possessed a BET surface area of 376.2 m2 g−1, a pore volume of 0.71 cm3 g−1 and mean pore diameter of 4.1 nm by using nitrogen adsorption–desorption measurement. The chemical composition was confirmed by Fourier transform infrared spectroscopy (FT-IR) and energy dispersive X-ray spectroscopy (EDX). The saturated adsorption capacity of the adsorbent toward Cd2+ reached up to 128 mg/g at pH 6. Langmuir isothermal adsorption model was proved to describe the adsorption data better. The adsorbent also possessed excellent kinetic property and attained equilibrium within 15 min. The adsorption process can be better described by the pseudo-second-order model than the pseudo-first-order model. Moreover, the adsorbent also exhibited specific adsorbent selectivity toward Cd2+ in presence of four competitor ions. The CdIMS was also capable in removing Cd2+ from water sample.

Aspartate family amino acids (AFAAs) have important commercial values due to their wide spectrum of applications. Most if not all AFAAs are produced under aerobic conditions which is energy-intensive. To establish a cost-effective anaerobic process for production of AFAAs, it holds great promise to develop a new pathway enabling the conversion of oxoloacetate into aspartate through direct amination which is catalyzed by aspartate dehydrogenase (AspDH). Compared with the well studied aspartate aminotransferase and aspartate ammonia-lyase, only a few AspDHs are characterized till date, and failure to reproduce the high activity of AspDH from Rastonia eutropha documented in the literature encouraged us to screen and characterize novel AspDHs from different origins. Interestingly, the AspDHs from Klebsiella pneumoniae 34618 (KpnAspDH) and Delftia sp. Cs1–4 (DelAspDH) showed successful soluble expression. KpnAspDH and DelAspDH containing C-terminal hexa-histidine tags were purified and characterized for their catalytic properties. Notably, in addition to its high reductive amination activity, DelAspDH exhibited considerable stability as compared to the other source of AspDHs. This work thus provides novel enzyme resource for engineering strains capable of producing AFAAs under anaerobic conditions.

Yeast cell wall plays an important role in the establishment and maintenance of cell morphology upon the cell wall stress. The cell wall of yeast consists of β-glucans, mannoproteins and chitin. The composition and structure remodel due to cell wall stress. Brewer's yeast cell wall exhibits stress response during long-term acclimation in order to adapt to environmental changes. This paper reviews the composition and structure of yeast cell wall and the molecular mechanisms of cell wall remodeling and signal pathway regulation.酵母细胞壁在细胞形态学的建立和维持中起重要作用，有助于细胞抵御环境变化。细胞壁主要由β-葡聚糖、甘露糖蛋白和几丁质组成，其组成和结构会由于压力胁迫发生动态重构。同时为了适应环境压力变化，啤酒酵母细胞壁在长期驯化过程中表现出相关压力应答机制。文中介绍了啤酒酵母细胞壁组成与结构，并综述了细胞壁重构与信号通路调控的分子机制。.

1,3-1,4-β-glucanase (E.C.3.2.1.73) is an important industrial enzyme which cleave β-glucans into oligosaccharides through strictly cutting the β-1,4 glycosidic bonds in 3-O-substituted glucopyranose units. Microbial 1,3-1,4-β-glucanase belongs to retaining glycosyl hydrolases of family 16 with a jellyroll β-sandwich fold structure. The present paper reviews the industrial application and protein engineering of microbial β-glucanases in the last decades and forecasts the research prospects of microbial β-glucanases.1,3-1,4-β-葡聚糖酶 (E.C.3.2.1.73) 是一种重要的工业用酶，其可以通过特异性切割毗邻β-1,3-糖苷键的β-1,4-糖苷键将β-葡聚糖或地衣多糖降解为纤维三糖和纤维四糖。微生物β-葡聚糖酶属于糖苷水解酶家族16，其三维结构为卷心蛋糕状的逆向β-片层结构。文中综述了近些年来β-葡聚糖酶在工业上的应用情况及酶蛋白质工程改造的研究进展，并对其研究前景进行了展望。.

Objective To simultaneously increase the thermostability and catalytic activity of barley β-amylase. Methods The amino acid sequences of various barley β-amylases with different enzyme properties were aligned, two amino acid residues R115 and T387 were identified to be important for barley β-amylase properties. R115C and T387V were then generated using site-directed and saturation mutagenesis. Results R115C and T387V mutants increased the enzyme catalytic activity and thermostability, respectively. After combinational mutagenesis, the T50 value and t(1/2,60oC) value of R115C/T387V mutant reached 59.4 °C and 48.8 min, which were 3.6 °C higher and 29.5 min longer than those of wild-type. The kcat/Km value of mutant R115C/T387V were 59.82/s·mM, which were 54.7% higher than that of wild-type. The increased surface hydrophobicity and newly formed strong hydrogen bonds and salt bridges might be responsible for the enzyme thermostability improvement while the two additional hydrogen bonds formed in the active center may lead to the catalytic property enhancement. Conclusions The mutant R115C/T387V showed high catalytic activity and thermostability indicating great potential for application in industry.

Protein Z4, an abundant of serpin storage proteins of Hordeum vulgare , is one major factor that benefits the stability of beer foam. In this study, protein Z4 from Canadian malt Metcalfe was cloned and expressed in Pichia pastoris . The glycosylated 45 kDa of recombinant protein Z4 was purified by Ni-NTA affinity column. The secondary structure of recombinant protein Z4 was detected via Circular Dichroism (CD) and Fourier Transform Infrared Spectroscopy (FTIR), and β-sheets and β-turns were the main structure of recombinant protein Z4. A few structural differences between recombinant protein Z4 and protein Z4 from malt were also analyzed, that more obvious α-helical structure and more S-H contents were detected in recombinant protein Z4. Meanwhile, higher structural stability of recombinant protein Z4 was also observed after incubating the samples in a wide range of temperature, pH and ethanol. These results confirmed the positive relationship between modifications by saccharides and high structural stability of recombinant protein Z4.

In beer quality, the interactions of proteins with hop acids are understood to be the basis of beer foam stability. Among beer proteins, one barley malt albumin, protein Z4, has an important role in stabilizing beer foam. In this study, protein Z4 was purified from AC Metcalfe barley malt for further study. The secondary structure of protein Z4 was investigated via Fourier transform infrared spectroscopy and circular dichroism spectroscopy. The results showed that protein Z4 had high structural stability. These structural features of protein Z4 were proposed to explain its observed high tolerance and stability of high temperatures and pH during the brewing process. Relatively high beer ethanol concentrations and yeast-induced modifications during the fermentation process can only partially influence in the structure of protein Z4. Modification by carbohydrates was observed as a result of the malting process. Meanwhile, modifications could increase the stability of the structure of protein Z4. Furthermore,...

Inspired by the fact that antibody recognizes antigen's epitope rather than its whole structure, we selected the glycosyl moiety of teicoplanin as the template, 4-vinylphenylboronic acid and methyl methacrylate as the functional monomers, and divinylbenzene as the cross-linker to synthesis molecularly imprinted polymer microspheres via precipitation co-polymerization. The glycosyl-imprinted microspheres can selectively capture the target glycopeptide antibiotic in aqueous solutions when the pH of surrounding environment is 9.0, and the captured antibiotic can be reversibly released when the pH falls below 4.0 again. This pH-controlled catch-and-release mechanism permits entrapping of glycopeptide antibiotics in slightly basic environments and keeping them entrapped under neutral conditions, and eluting in acidic media. Five teicoplanin components were selectively captured by using the prepared glycosyl-imprinted microspheres as solid-phase extraction adsorbents, and then detected using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). Finally, the method was thoroughly validated for accuracy and reproducibility by determining teicoplanin in food and biological samples, and achieving quantification limits of 0.1 μg/kg, 0.5 μg/L and 1.0 μg/L for milk, urine and plasma samples, respectively.

Gibberellic acid (GA3) was added to three types of beer barley, and the chemical changes to GA3 during the beer brewing process were studied using HPLC. The results demonstrated that the GA3 concentration decreased throughout the malting, mashing, and boiling processes and that no GA3 was detected in the congress wort. A new substance, herein called Substance A, was detected by HPLC analysis using a C18 column; this substance exhibited retention characteristics different from GA3. The concentration of Substance A increased throughout the malting, mashing, and boiling processes. Mass spectrometry revealed that Substance A has the same molecular weight as GA3 and nuclear magnetic resonance studies determined that Substance A is a structural isomer of GA3. PRACTICAL APPLICATION: This study developed a new idea to understand GA3 behavior during the brewing, which provided a practical reference for food safety in beer and other fields using GA3 as a food additive.

Acetaldehyde is synthesized by yeast during the main fermentation period of beer production, which causes an unpleasant off-flavor. Therefore, there has been extensive effort toward reducing acetaldehyde to obtain a beer product with better flavor and anti-staling ability. In this study, we discovered that acetaldehyde production in beer brewing is closely related with the intracellular NADH equivalent regulated by the citric acid cycle. However, there was no significant relationship between acetaldehyde production and amino acid metabolism. A reverse engineering strategy to increase the intracellular NADH/NAD

The morphological structure and physiological indexes of Saccharomyces cerevisiae have changed during serial re-pitching due to the stress conditions in serial handlings and the cells become aging. It is of great significance to study the physiological changes of S. cerevisiae during serial re-pitching to understand the anti-aging effect of S. cerevisiae. In this paper, the changes of the physiological indexes during re-pitching of yeast are summarized, and based on the analysis of the previous works further research directions are proposed.酿酒酵母在进行连续传代的过程中，细胞的形态结构以及细胞内的各项生理指标因受胁迫条件的影响而发生改变，细胞出现逐渐衰老现象。深入了解酿酒酵母在传代中的生理变化对酿酒酵母抗衰老研究具有重要意义。文中综述了酿酒酵母在传代过程中各项生理指标的变化，并提出了进一步研究的方向，以期为酵母在工业生产中的抗衰老研究提供理论依据和参考。.

This study aimed to investigate the contamination degree and quality control of seven breweries from the Yangtze River Delta region, China. A total of 205 spoilage bacteria strains were isolated and no wild yeast was observed. The vast majority of the spoilage bacteria belonged to Lactobacillus, Lactococcus, and Leuconostoc species and 28.8% of them could grow in beer. Among the seven sampling points, fermented beer, finished beer, and equipment contained larger amounts of spoilage bacteria. The most abundant of the spoilage bacteria that could grow in beer existed in fermented beer and the number of spoilage bacteria was significantly reduced in the finished beer. The equipment in fermentation and packaging workshops showed high percentages of spoilage bacteria that could grow in beer. This indicated that more attention should be paid in controlling the spoilage bacteria in the fermentation and packaging processes. The hop tolerance related gene analysis showed that the majority of spoilage bacteria contained at least one of the HorA, HorC and HitA genes. None of these genes were observed in the two spoilage bacteria strains that could grow in the beer. This information could be useful for breweries in the Yangtze River Delta region for removing risks in order to produce high-quality products in good microbial condition.

Lager-brewing yeasts are mainly used for the production of lager beers. Illumina and PacBio-based sequence analyses revealed an approximate genome size of 22.8 Mb, with a GC content of 38.98%, for the Chinese lager-brewing yeast Saccharomyces sp. strain M14. Based on ab initio prediction, 9,970 coding genes were annotated.

Brewer's yeast is crucial in beer fermentation, mainly beer flavor diversity and stability. Beer flavor stability is one of the most influential beer quality aspects, and screening or breeding brewer's yeast with enhanced anti-staling capacity will be an effective solution. In recent decades, with the progress of genetic engineering and detailed description of brewer's yeast genome, great efforts have been made to improve brewer's yeast. This review highlights recent advances in classical and genetic engineering improvement of yeasts to produce more antioxidant compounds or less beer aging substances and precursors. Therein, improvement targets, evaluation methods and development strategies of anti-staling brewer's yeast are also discussed. Furthermore, hotspot and future trend of anti-staling yeast strain development are also proposed.啤酒酵母是啤酒酿造的核心,对啤酒风味多样性及风味稳定性具有重要影响。风味稳定性是啤酒重要的质量指标之一，筛选或选育综合抗老化能力高的优良啤酒酵母菌株将成为有效解决该问题的途径之一。近年来，随着基因工程技术的发展及啤酒酵母基因组的不断阐明，人们对啤酒酵母菌种改良展开了大量的研究，以期解决啤酒酿造问题，改善啤酒质量。本文对采用传统方式及基因工程手段选育高产抗氧化物质或低产啤酒老化物质及老化前驱物的啤酒酵母的最新研究进展进行了综述。其中，对抗老化啤酒酵母的选育目标、评价方法及选育策略进行了讨论，并对抗老化啤酒酵母选育的研究热点及发展趋势进行了展望。.

This study aimed to elaborate the effect of N-glycosylation and glycation of protein Z