High sodium salt concentration is crucial for successful fermentation and flavor development in bean-based fermented foods (BBFFs), yet excessive sodium intake poses health risks. As healthy diet awareness grows, reducing sodium salt in BBFFs is increasingly demanded but highly challenging due to the critical role of sodium salt reduction in BBFFs production. To resolve this challenge, researchers and manufacturers have developed various methods, however they showed differentiated results due to the diversity of BBFFs. This review briefly elaborated the problems of sodium salt reduction in BBFFs industry at the microbiological, flavor and metabolic aspects. Moreover, this review emphasized the characteristics and application effect of sodium salt reduction methods which were classified into two principles (less sodium salt in and more sodium salt out). Finally, four future prospects for sodium salt reduction in BBFFs industry are outlooked. This review provides guidance for the production low-salt BBFFs with preferred flavor and quality.

This study employed an integrated approach of comparative transcriptomics and heterologous expression to identify and characterize important proteolytic enzymes from Aspergillus oryzae for enhancing doubanjiang fermentation. Comparative transcriptomic analysis between A. oryzae BL18 and 3.042 during koji-making identified 12 differentially expressed proteolytic enzyme genes. These candidate genes were heterologously expressed in Komagataella phaffii GS115 for enzymatic property characterization. Two proteolytic enzymes with relatively good stability under high salinity were identified. GME1468_g and GME389_g enzymes could retain 54.52 % and 28.42 % of their activities after treatment in 18 % salinity for 7 days, respectively. Furthermore, GME389_g enzyme was beneficial for the hydrolysis of globulin while GME1468_g enzyme preferred albumin hydrolysis. Based on these characterized properties, GME1468_g and GME389_g enzymes were applied individually and in combination in doubanjiang fermentation. The application of GME1468_g enzyme yielded the most significant improvement in product quality, resulting in the highest concentrations of amino acid nitrogen (0.88 g/100 g) and free amino acids (23.27 g/100 g), which were 66.04 % and 30.21 % higher than those in control group (0.53 g/100 g and 17.87 g/100 g, p < 0.05). This group also exhibited a significantly increased concentration of total volatile flavor compounds while nine key volatile flavor compounds in doubanjiang. The addition of GME1468_g enzyme also led to better sensory characteristics with stronger jiang aroma with clearly perceptible floral and fruity aroma. This work established a methodological framework for mining functional enzymes from key microbes and demonstrated its successful application in traditional food fermentation.

Lager yeast, which is mainly used for lager beer brewing, withstands significant oxidative stress during brewing process, leading to its rapid aging in serial beer brewing. Mitophagy plays a critical role in the antioxidant stress response of yeast. However, the relationship between mitophagy and the antioxidant capacity of yeast is still unclear. Previous studies indicated that ATG gene family in mitophagy significantly affects the antioxidant capacity of yeast cells in beer brewing. Herein, the expression of ATG8, ATG11, ATG32, DNM1, and MMM1 genes was regulated. The results showed that the overexpression of ATG8 and ATG11 significantly reduced the intracellular ROS contents to 52.05% and 22.57% of the initial state, respectively, and helped to maintain a high mitochondrial vitality during serial fermentation. Disruption of ATG8, ATG11 and ATG32 resulted in significant decrease in cell vitality when exposed to H2O2 stimulation. Meanwhile, the disruptions of these genes were detrimental to the balance of intracellular ROS. Excess DNM1 activity could affect the cellular energy balance and ATP depletion under prolonged stress conditions. The repression of MMM1 led to lower ATP levels during serial beer fermentation. The ATG8, ATG11, and ATG32 genes might be potential targets for regulating the antioxidant capacity of yeast. The current work provides new insights into improving the antioxidant capacity of yeast through mitophagy regulation.

Brewer's spent grain (BSG) and brewer's spent yeast (BSY) are two major brewing by-products, which are low-cost raw materials with high yields and nutritional value. In this study, the antioxidant peptides from brewing by-products were separated, purified and identified by UF, GFC or HIC, semi-preparative RP-HPLC, and nano-HPLC-MS/MS. Thereafter, in silico analysis was applied to predict the bioactivity, toxicity, and bioavailability of the identified peptides, and a total of 23 potential novel peptides with antioxidant activity and bioavailability were excavated. Furthermore, molecular docking results revealed the potential antioxidant peptides had stable binding ability to Keap1, and Tyr334, Arg380, Arg415, Arg483, and Tyr525 residues contributed enormously to docking, all of which were located in the binding sites of Keap1-Nrf2 interaction. Peptides with the lowest binding energy (i.e. AGRLPW, DRLW, KPW, PLWWRHPR, RVWNPFR, and ANLPWLGK) were further synthesized and validated in vitro and at the cellular level to be bioactive. Western blot results showed that KPW, RVWNPFR, and ANLPWLGK could protect HaCaT cells from H2O2-induced oxidative damage by activating Keap1-Nrf2 pathway. These findings provided insights into the high value-added utilization of brewing by-products.

This study aimed to obtain an Aspergillus oryzae strain with high protease activity and to evaluate its potential to apply as starter culture in bean-based fermented foods (BBFFs) production using doubanjiang fermentation as research model. A. oryzae BL18 with higher protease activity than the commonly used starter A. oryzae 3.042 was obtained through two rounds of screening. Moreover, this strain was also proved to be safe to apply in BBFFs fermentation due to the lack of the ability to produce aflatoxin B1 through genomic and experimental analysis. A. oryzae BL18 was optimal to grow under 0-12% salinity, 25-40 degrees C and pH4-6. During koji-making, A. oryzae BL18 had stronger ability to produce spores (4.19 x 108 spores/g dry weight) and to secrete protease (4654.35 U/g) than A. oryzae 3.042 (2.89 x 108 spores/g dry weight and 3604.40 U/g). Significantly higher concentrations of umami amino acids and volatile flavor compounds were found in doubanjiang fermentation inoculated by A. oryzae BL18 while better sensory characteristics were observed. Therefore, A. oryzae BL18 might be a promising starter to apply in fermentation of doubanjiang or other BBFFs.

ImportanceAdenomyosis is a common chronic gynecological disorder, and its treatment is an unmet need. New therapies need to be developed. Mifepristone is being tested for adenomyosis treatment. ObjectiveTo determine whether mifepristone is effective and safe for adenomyosis treatment. Design, Setting, and ParticipantsThis multicenter, placebo-controlled, double-blind randomized clinical trial was conducted in 10 hospitals in China. In total, 134 patients with adenomyosis pain symptoms were enrolled. Trial enrollment began in May 2018 and was completed in April 2019, and analyses were conducted from October 2019 to February 2020. InterventionsParticipants were randomized 1:1 to receive mifepristone 10 mg or placebo orally once a day for 12 weeks. Main Outcomes and MeasuresThe primary end point was the change in adenomyosis-associated dysmenorrhea intensity, evaluated by the visual analog scale (VAS) after 12 weeks of treatment. Secondary end points included the change in menstrual blood loss, increased level of hemoglobin in patients with anemia, CA125 level, platelet count, and uterine volume after 12 weeks of treatment. Safety was assessed according to adverse events, vital signs, gynecological examinations, and laboratory evaluations. ResultsIn total, 134 patients with adenomyosis and dysmenorrhea were randomly assigned, and 126 patients were included in the efficacy analysis, including 61 patients (mean [SD] age, 40.2 [4.6] years) randomized to receive mifepristone and 65 patients (mean [SD] age, 41.7 [5.0] years) randomized to received the placebo. The characteristics of the included patients at baseline were similar between groups. The mean (SD) change in VAS score was -6.63 (1.92) in the mifepristone group and -0.95 (1.75) in the placebo group (P<.001). The total remission rates for dysmenorrhea in the mifepristone group were significantly better than those in the placebo group (effective remission: 56 patients [91.8%] vs 15 patients [23.1%]; complete remission: 54 patients [88.5%] vs 4 patients [6.2%]). All the secondary end points showed significant improvements after mifepristone treatment for menstrual blood loss, hemoglobin (mean [SD] change from baseline: 2.13 [1.38] g/dL vs 0.48 [0.97] g/dL; P<.001), CA125 (mean [SD] change from baseline: -62.23 [76.99] U/mL vs 26.89 [118.70] U/mL; P<.001), platelet count (mean [SD] change from baseline: -28.87 [54.30]x10(3)/mu L vs 2.06 [41.78]x10(3)/mu L; P<.001), and uterine volume (mean [SD] change from baseline: -29.32 [39.34] cm(3) vs 18.39 [66.46] cm(3); P<.001). Safety analysis revealed no significant difference between groups, and no serious adverse events were reported. Conclusions and RelevanceThis randomized clinical trial showed that mifepristone could be a new option for treating patients with adenomyosis, based on its efficacy and acceptable tolerability. Trial RegistrationClinicalTrials.gov Identifier: NCT03520439

Ribonucleic acid (RNA) and its degradation products find widespread application across various industries, including the food condiments sector. This study employed comparative transcriptomics to investigate the genetic mechanisms underlying RNA synthesis in the mutant Saccharomyces pastorianus strain G03H8, which exhibited a high RNA yield. To identify genetically engineered targets, single gene over-expression and CRISPR/Cas9 gene editing technology were utilized. The differential enrichment results revealed a close association between RNA metabolism and cellular processes such as the cell cycle, purine metabolism, nucleotide metabolism, and other metabolic pathways. Subsequently, we selected the top nine most promising genes to evaluate their impact on RNA synthesis. In these nine targets, upon comparing the RNA yield of the genetically engineered strains, G03-TAL1, G03-PGM2, G03-ΔPRS5, and G03-△DBP8, with the parent strain G03, significant improvements of 31.7%, 41.8%, 72.1%, and 46.7% were observed, respectively. Furthermore, these four genes were found to enhance the strain's growth and augment the pentose phosphate pathway, thus demonstrating the considerable potential for enhancing RNA yield. Notably, this study represents the first instance of identifying the upregulation of TAL1, PGM2, PRS5, and DBP8 as a means to increase RNA content in S. pastorianus. Consequently, our findings present novel genetic targets for enhancing RNA production and contribute to a deeper understanding of the mechanisms involved in high RNA synthesis in S. pastorianus.

This study aimed to elaborate the effect of temperature on doubanjiang fermentation. Two batches of constanttemperature groups were prepared and their physicochemical parameters, color formation, metabolites and microbial community dynamics during fermentation were determined and compared with those of natural temperature fermentation group. The results showed that fermentation at 40 degrees C could accelerate the accumulation of amino nitrogen, reducing sugar, amino acids, organic acids and various volatile metabolites while it was able to inhibit the growth of conditionally pathogenic bacteria, such as Klebsiella and Salmonella. However, high concentrations of total acids and biogenic amines, protrusive burnt flavor and darker color were observed in constant temperature fermentation, which were unfavorable for doubanjiang quality. Higher fermentation temperature lowered the diversity of bacterial community and favored the growth of Bacillus genus. The correlation between key microbial genera and doubanjiang quality indexes were significantly different among different temperatures. This study would deep our understanding of the roles of temperature on doubanjiang fermentation.

Flocculation of brewer's yeast is an environment-friendly and cost-effective way to separate yeast cells from fermentation broth for subsequent production. Diverse genetic background and complex fermentation environment cause difficulty to explore flocculation mechanism and regulate yeast flocculation. In this study, comparative transcriptome analysis was carried out between an industrial brewing yeast and its flocculation-enhanced mutant strain, unveiling the differentially-expressed genes were enriched in response to stresses. The expression level of Lg-FLO1 was the highest among all FLO genes. Environmental stresses of fermentation were simulated to stimulated yeast cells and it was found that nitrogen and amino acid starvation promoted the process of flocculation. It is the first time to reveal the nutrient-responsive gene RIM15 has a novel genetic function regulating flocculation. The study provides novel direction and strategies to manage yeast flocculation and achieve effective cell utilization in fermentation.

苯并呋咱类荧光探针具有斯托克斯位移大、摩尔消光系数大以及荧光量子产率高等优点,具有较强的荧光传感开发价值.该研究设计并合成了一种苯并呋咱类荧光探针,探究了该荧光探针与乙醛的荧光性质,并成功应用于酒类样品中乙醛含量的检测,并提出利用蒸馏法去除酒类中酮酸类物质等的干扰,线性范围和回收率分别为0.12～200 mg/L和91.50％～111.14％,开发的检测方法与气相色谱结果相比并无显著性差异.该研究提出的荧光探针检测方法为酒类质量管控提供了一种新思路.

高浓酿造技术是啤酒工业中常用的生产技术,选育发酵性能优良的高浓酿造啤酒酵母具有重要的生产意义.以啤酒酵母(Saccharomyces pastorianus)G03为出发菌株,利用基因组重排技术,结合杜氏小管产气实验、菌株耐受性测试、三角瓶发酵实验三轮筛选,选育高效发酵的高浓酿造啤酒酵母.G03经过了常压室温等离子体诱变处理和两轮递推式原生质体融合,最终获得了发酵速度及真正发酵度均提高的菌株F2-123,且主要风味成分的含量没有受到明显影响.F2-123传代发酵性能稳定,啤酒发酵实验结果表明其在24 °P麦汁中、11℃发酵周期为11 d,与出发菌株G03相比,F2-123发酵周期缩短了 1d,酒精度提高了 8.9％,真正发酵度提高了6.5％,其他风味物质没有明显差异.该研究获得的菌株在啤酒高浓酿造生产中具有一定的应用潜力.

Mitophagy is a process whereby cells selectively remove mitochondria through the mechanism of autophagy, which plays an important role in maintaining cellular homeostasis. In order to explore the effect of mitophagy genes on the antioxidant activities of Saccharomyces cerevisiae, mutants with deletion or overexpression of mitophagy genes ATG8, ATG11 and ATG32 were constructed respectively. The results indicated that overexpression of ATG8 and ATG11 genes significantly reduced the intracellular reactive oxygen species (ROS) content upon H2O2 stress for 6 h, which were 61.23% and 46.35% of the initial state, respectively. Notable, overexpression of ATG8 and ATG11 genes significantly increased the mitochondrial membrane potential (MMP) and ATP content, which were helpful to improve the antioxidant activities of the strains. On the other hand, deletion of ATG8, ATG11 and ATG32 caused mitochondrial damage and significantly decreased cell vitality, and caused the imbalance of intracellular ROS. The intracellular ROS content significantly increased to 174.27%, 128.68%, 200.92% of the initial state, respectively, upon H2O2 stress for 6 h. The results showed that ATG8, ATG11 and ATG32 might be potential targets for regulating the antioxidant properties of yeast, providing a new clue for further research.

This study aimed to elaborate the contributions of sunlight-expose process and core-microbiota metabolism on improving the Doubanjiang flavor profile. Four Doubanjiang fermentation models were designed with sunlight-expose and core-microbiota metabolism as independent variable. It was found that the synergism of sunlight-expose and core taxa metabolism was favorable to improve the diversity of volatile and non-volatile com-pounds during Doubanjiang fermentation, a total of 49 VOCs were screened to characterize this effect contributed by sunlight and core taxa. The contribution for core-microbiota metabolism to flavor profile reached 71.3%, which was much higher than that of sunlight-expose process (28.6%), Additionally, the proportion of Staphy-lococcus (31.9%) and Zygosaccharomyces (21.9%) is more prominent to flavor profile among 4 core microor-ganisms after RDA analysis, and the environment with light-expose was beneficial to promote the growth of A. oryzae, S. carnosus and Z. rouxii. The situ fermentation was conducted to further verify the role of sunlight-expose, Z. rouxii and S. carnosus in improving the Doubanjiang flavor profile. This study was conducive to reveal the scientific mechanism behind the traditional Doubanjiang fermentation, and provide the new insight to Doubanjiang brewing technology.

Key Points Question Is mifepristone effective for adenomyosis treatment? Findings In this randomized clinical trial of 134 participants with adenomyosis pain symptoms, the participants in the mifepristone group and had significantly greater improvement in pain scores than the placebo group. All the secondary outcomes, including hemoglobin, platelet count, and uterine volume, showed significant improvements in the mifepristone group, and there were no serious adverse events. Meaning This randomized clinical trial found that mifepristone was effective and safe for the treatment of adenomyosis, which supports the repositioning of this drug as a new treatment option for adenomyosis.

红枣富含活性成分,但存在不易储存、直接食用过于甜腻等问题,红枣产业体量小、附加值低.为筛选适合红枣汁发酵的菌株,从实验室保藏菌株和水果自然发酵液中筛选得到204株菌株,分析其发酵性能、益生潜力和发酵产品中风味物质组成等,获得1株有着益生菌特性且在红枣汁中发酵风味优良的植物乳植杆菌MY-12,使用该菌株发酵初始含糖量14％的红枣汁,发酵周期为48 h,发酵结束后发酵液糖酸比为20:1(其中乳酸占有机酸93.01％),酒精含量低于0.1％,饮料有着明显红枣益生菌饮料的典型性,口感协调,香味馥郁,且红枣甜腻风味与涩味口感得到明显改善.研究结果对改善目前国内红枣资源深加工不足的现状,提升红枣农产品深加工的经济和社会效益有着重要参考价值,为发酵型益生饮料的研发提供了新的思路.

Zygosaccharomyces rouxii (Z. rouxii) and Staphylococcus carnosus (S. carnosus) are fundamental taxa in spontaneous bean-based food fermentation, playing a vital role in flavor generation and macromolecule degradation. The present study aimed to investigate the biological mechanisms underlying the interaction between Z. rouxii Y8 and S. carnosus M43 in BBP (broad bean paste) moromi by mono- and co-culture. It was found that the biomass of Z. rouxii and S. carnosus was higher in co-culture than that in mono-culture (p < 0.05), indicating that a facilitation relationship among them. Moreover, the observed intensity of facilitation (OIF) peaked at 0.479 & PLUSMN; 0.002 under aerobic conditions, which was higher than that under anaerobic conditions (0.147 & PLUSMN; 0.014). Furthermore, the facilitative microbial interaction showed the stability and robustness during co-culture with different inoculum proportions (1:3, 1:5, 1:7, 1:10) and cell passage from 1 to 4 generations. Physical separation co-culture and acetic acid tolerance test revealed that acetic acid played a crucial role in regulating the interaction between Z. rouxii (R2 = 0.6955) and S. carnosus (R2 = 0.7097), with metabolic complementarity and inhibition alleviation as the underlying mechanisms. Additionally, Z. rouxii and S. carnosus as starter could enhance the accumulation of flavor compound, and accelerate the maturity of BBP fermentation. The dissection of interaction between Z. rouxii and S. carnosus provided valuable insights for revealing the complex web of relationships among microbiota and the development of microbial starter in BBP brewing ecosystem.

Yeast autolysis affects the flavor and quality of beer. The regulation of yeast autolysis is a need for industrial beer production. Previous studies on brewer's yeast autolysis showed that the citric acid cycle-related genes had a great influence on yeast autolysis. To explore the contribution of isocitrate dehydrogenase genes in autolysis, the IDP1 and IDP2 genes were destroyed or overexpressed in typical lager yeast Pilsner. The destruction of IDP1 gene improved the anti-autolytic ability of yeast, and the anti-autolytic index after 96 h autolysis was 8.40, 1.5 times higher than that of the original strain. The destruction of IDP1 gene increased the supply of nicotinamide adenine dinucleotide phosphate (NADPH) and the NADPH/NADP+ ratio was 1.94. After fermentation, intracellular ATP level was 1.8 times higher than that of the original strain, while reactive oxygen species (ROS) was reduced by 10%. The destruction of IDP2 gene resulted in rapid autolysis and a decrease in the supply of NADPH. Anti-autolytic index after 96 h autolysis was 4.03 and the NADPH/NADP+ ratio was 0.89. After fermentation, intracellular ATP level was reduced by 8% compared with original strain, ROS was 1.3 times higher than that of the original strain. The results may help understand the regulation mechanism of citric acid cycle-related genes on yeast autolysis and provide a basis for the selection of excellent yeast with controllable anti-autolytic performance.

This study aimed to elaborate the assembly processes and metabolic regulation of the microbial community under the conditions of environmental factors and artificial intervention using broad bean paste (BBP) fermentation as a tractable research object. Spatial heterogenicity of amino acid nitrogen, titratable acidity, and volatile metabolites were observed between upper and lower layers after fermentation for 2 weeks. Amino nitrogen contents in the upper fermented mash reached 0.86, 0.93, and 1.06 g/100 g at 2, 4, and 6 weeks, respectively, which were significantly higher than those of mash located at the lower layer (0.61, 0.79, and 0.78 g/100 g). Moreover, higher concentrations of titratable acidity were accumulated in upper layers (2.05, 2.25 and 2.56 g/100g) than those in lower layers, and the differentiation of volatile metabolites was the greatest (R = 0.543) at 36 days, after which the BBP flavor profiles converged with the fermentation progress. The successive heterogenicity of the microbial community in the mid-late stage was also found during fermentation, and Zygosaccharomyces, Staphylococcus, and Bacillus had heterogeneous characteristics driven by sunlight, water activity, and microbial interactions. This study provided new insights into the mechanisms underlying the succession and assembly of the microbial community of BBP fermentation, which also laid new clues for researches of the microbial communities in complex ecosystems. IMPORTANCE Gaining insights into the community assembly processes is essential and valuable for the elaboration of underlying ecological patterns. However, current studies about microbial community succession in multispecies fermented food usually treat the research object as a whole, are focused exclusively on temporal dimensions, and have ignored the changes of community structure in spatial dimensions. Therefore, dissecting the community assembly process from the view of spatiotemporal dimensions will be a more comprehensive and detailed perspective. Here, we found the heterogenicity of the BBP microbial community under the traditional production technology from spatial and temporal scales, systematically analyzed the relationship between the spatiotemporal succession of community and the difference of BBP quality, and elucidated the roles of environmental factors and microbial interactions to drive the heterogeneous succession of the microbial community. Our findings provide a new insight into understanding the association between microbial community assembly and the quality of BBP.

This study aimed to provide a systematic analysis of the effect of environmental factors on the growth and volatile flavor compounds (VFCs) production ability of Zygosaccharomyces rouxii Y-8 and further elucidate its contribution to doubanjiang fermentation in different salinity. Lower salinity (0-9%), acidic pH (4.5-5.5), moderate temperature (25-35 degrees C) and air exposure favored the growth and VFCs accumulation of Z. rouxii Y-8, which also had higher concentrations of key jiang flavor contributing compounds benzene ethanol, 2-methoxyphenol and pyrazines. Interestingly, samples with higher VFCs concentration were found to contain less kinds of VFCs. When inoculated into doubanjiang fermentation, Z. rouxii Y-8 showed critical roles on the formation of VFCs in doubanjiang. Among doubanjiang samples fermented in different salinity, doubanjiang with 9% salinity had the highest kinds of VFCs. Moreover, its flavor was more balanced and the jiang flavor was stronger. This indicated that the presence of adequate salinity was necessary for Z. rouxii Y-8 to produce critical VCFs responsible for doubanjiang flavor. The results would provide researchers and manufacturers with a deeper understanding of the characteristics of Z. rouxii Y-8 and rationales to utilize Z. rouxii Y-8 as starter to produce high quality BBFFs.

Black garlic (BG) is a kind of garlic intensive processing product, and its flavor and physiological activity are mainly derived from alliin and its related sulfides. The thermal stabilities of alliin, S-allyl-L-cysteine (S-ALC) and gamma-glutamyl-cysteine (gamma-GC) during BG processing were investigated in this study. The results showed that gamma-GC was more stable than alliin and S-ALC, and the activities of alliinase, gamma-glutamyl transpeptidase and gamma-glutamyl-cysteine synthetase were completely inactivated at 50 degrees C for 18 h, so, the changes of alliin and related sulfides in subsequent stages didn't correlated with the three enzymes. Alliin and its related sulfides changed significantly during the Maillard reaction stage. Further researches showed that the total content of alliin, S-ALC and gamma-GC in BG could increase by 20.1% under the optimal conditions where humidity at 90%, temperature at 80 degrees C, and the processing time at 210 h. The sensory analysis indicated that the optimal BG samples scored higher in color, dryness, garlic meat texture, smell, mouthfeel. In addition, the sour and sweet taste was more coordinated, and the bitterness was significantly reduced after the process optimization. These results could be helpful for the improving of BG processing technologies, products quality, and related physiological activity in food industry.