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11.
Aspergillus oryzae (A. oryzae) is an important starter in the fermentation of koji and moromi. However, the effect of different A. oryzae strains on the quality of moromi has rarely been studied. For this reason, this study analyzed the physicochemical properties, enzyme activity, sensory quality, and metabolite profiles of moromi samples fermented using two strains (A. oryzae KCCM12012P (moromi-1) and KCCM12804P (moromi-2)), which were newly isolated from fermented soy foods, and compared them to those of a commercialized A. oryzae strain (control). Amino-type nitrogen contents of moromi-1 and moromi-2 samples were higher than that of control moromi, and their amylase and protease activities were also higher. Moreover, metabolite profiles of moromi were significantly altered according to strains. In particular, the levels of many amino acids, peptides, nucleotides, and acidic compounds were altered, which resulted in changes in the sensory quality of moromi. Although volatile compounds were not investigated, the results suggested that the quality of moromi was significantly different for newly isolated strains, especially A. oryzae KCCM12804P, and they were superior to the commercial strain in terms of taste-related substances. Therefore, these strains could be used as good starters to produce moromi and soy sauce with good sensory quality.  相似文献   
12.
The root of Smilax china L. is used in traditional Korean medicine. We found that the Smilax china L. root extract has strong antimicrobial activity against two Cutibacterium acnes strains (KCTC 3314 and KCTC 3320). The aim of this study was to identify the beneficial properties of Smilax china L. extracts for their potential use as active ingredients in cosmetics for the treatment of human skin acne. The high-performance liquid chromatography (HPLC) and liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC/QTOF/MS) methods were used to obtain the profile of secondary metabolites from the ethyl acetate-soluble fraction of the crude extract. Agar diffusion and resazurin-based broth microdilution assays were used to evaluate antimicrobial activity and minimum inhibitory concentrations (MIC), respectively. Among the 24 metabolites, quercetin, resveratrol, and oxyresveratrol were the most potent compounds against Cutibacterium acnes. Minimum inhibitory concentrations of quercetin, resveratrol, and oxyresveratrol were 31.25, 125, and 250 μg/mL, respectively.  相似文献   
13.
Obesity is a growing global epidemic that can cause serious adverse health consequences, including insulin resistance (IR) and nonalcoholic fatty liver disease (NAFLD). Obesity development can be attributed to energy imbalance and metabolic inflexibility. Here, we demonstrated that lack of Kelch-like protein 3 (KLHL3) mitigated the development of obesity, IR, and NAFLD by increasing energy expenditure. KLHL3 mutations in humans cause Gordon’s hypertension syndrome; however, the role of KLHL3 in obesity was previously unknown. We examined differences in obesity-related parameters between control and Klhl3−/− mice. A significant decrease in body weight concomitant with fat mass loss and improved IR and NAFLD were observed in Klhl3−/− mice fed a high-fat (HF) diet and aged. KLHL3 deficiency inhibited obesity, IR, and NAFLD by increasing energy expenditure with augmentation of O2 consumption and CO2 production. Delivering dominant-negative (DN) Klhl3 using adeno-associated virus into mice, thereby dominantly expressing DN-KLHL3 in the liver, ameliorated diet-induced obesity, IR, and NAFLD. Finally, adenoviral overexpression of DN-KLHL3, but not wild-type KLHL3, in hepatocytes revealed an energetic phenotype with an increase in the oxygen consumption rate. The present findings demonstrate a novel function of KLHL3 mutation in extrarenal tissues, such as the liver, and may provide a therapeutic target against obesity and obesity-related diseases.Subject terms: Obesity, Homeostasis  相似文献   
14.
As an important microbial resource, Actinomycetes, especially Streptomyces, have important application values in medicine and biotechnology. Streptomyces fungicidicus SYH3 was isolated from soil samples in tomato-growing areas and showed good inhibitory effects on Alternaria solani in tomato. To obtain pure active compounds, SYH3 fermentation broth was subjected to XAD-16 macroporous resin and silica gel column chromatography. Combined with the repeated preparation and separation of preparative high-performance liquid chromatography (HPLC), a total of four monomer compounds were obtained after activity tracking. Compound 4 was identified as a new six-membered lactone ring compound named 6-(5-hydroxy-6-methylheptyl)-5,6-dihydro-2H-pyran-2-one by 1D and 2D nuclear magnetic resonance (NMR) data and mass spectrometry (MS). The other three active compounds belong to the cyclodipeptide, and their half maximal inhibitory concentration (IC50) values against A. solani were 43.4, 42.9, and 30.6 μg/mL, respectively. Compound 4 significantly inhibited the spore germination and induced swollen and deformed local hyphae of A. solani with an IC50 value of 24.9 μg/mL. Compound 4 also had broad-spectrum antifungal activity and had a good antifungal effect on the tested plant-pathogenic fungi. The modes of action of new compound (4) still require further investigation, representing a novel and effective anti-fungal agent for future application.  相似文献   
15.
16.
Sodium-ion storage devices are highly desirable for large-scale energy storage applications owing to the wide availability of sodium resources and low cost.Transition metal nitrides(TMNs)are promising anode materials for sodium-ion storage,while their detailed reaction mechanism remains unexplored.Herein,we synthesize the mesoporous Mo3N2 nanowires(Meso-Mo3N2-NWs).The sodium-ion storage mechanism of Mo3N2 is systematically investigated through in-situ XRD,ex-situ experimental characterizations and detailed kinetics analysis.Briefly,the Mo3N2 undergoes a surface pseudocapacitive redox charge storage process.Benefiting from the rapid surface redox reaction,the Meso-Mo3N2-NWs anode delivers high specific capacity(282 m Ah g-1 at 0.1 A g-1),excellent rate capability(87 m Ah g-1 at 16 A g-1)and long cycling stability(a capacity retention of 78.6%after 800 cycles at 1 A g-1).The present work highlights that the surface pseudocapacitive sodium-ion storage mechanism enables to overcome the sluggish sodium-ion diffusion process,which opens a new direction to design and synthesize high-rate sodiumion storage materials.  相似文献   
17.
A rapid way assisted by microwave irradiation was proposed to synthesize poly[2,2'-(m-phenylene)-5,5'-bibenzimidazole](PBI) and poly(2,5-benzimidazole)(ab-PBI).Synthesis of PBI in polyphosphoric acid is conducted for 20 h or even more.Under microwave irradiation,the polycondensations could be completed in polyphosphoric acid within 3 h from 3,3'-diaminobenzidine tetrahydrochloride(DAB·4HCl·2H2O) and isophthalic acid for PBI,and from 3,4-diaminobenzoic acids(DABA) for ab-PBI,respectively.The conditions for t...  相似文献   
18.
Russian Physics Journal - The paper presents the development of the statistical theory of phase transformation of lithium aluminum amide with the formation of ammonia. Free energies of phases are...  相似文献   
19.
We studied the cascade nucleophilic addition reactions of 1,2,3-triazines with activated acetonitriles or ketones,which were used to construct highly substituted pyridines that are not easily accessed by conventional methods.The strategy addressed some structural diversity issues currently facing medicinal chemistry,and the resulting pyridines could be used as convenient precursors for the synthesis of related pharmaceuticals.In particular,our method was applied to the syntheses of the marketed drug etoricoxib and several biologically important molecules in a few steps.  相似文献   
20.
以豆甾醇(stig.)为印迹分子、甲基丙烯酸甲酯(MMA)为功能单体、二乙烯基苯(DVB)为交联剂、碳酸钙及十二烷基硫酸钠(SDS)混合物为分散剂、过硫酸钠为引发荆、极性较低的甲醇(tolu.)为致孔剂,采用悬浮聚合法合成豆甾醇分子印迹聚合物.并对试验合成的分子印迹聚合物的形貌、粒径及选择吸附性能分别采用高效液相、电镜和光学显微镜进行分析和评价.试验结果表明,最佳配方为3g stig.:40mL MMA:15mL DVB:4g CaCO3 2g SDS:0.4mLNa2S2O8:14mL tolu.,其中引发荆过硫酸钠应分多次加入,在聚合反应初期采用高速搅拌,随着聚合反应的进行搅拌速度应逐渐减小.该条件下合成的分子印迹聚合物平均粒径小于100μm、分布较窄,对豆甾醇表现出快速和稳定的特异吸附性能,其分离因子超过1.65,吸附容量约为1.2mg/g.  相似文献   
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