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Fused cast Al2O3-ZrO2-SiO2 (AZS) refractory is the key building material of glass furnace. Calcined aluminum oxide powder and ordinary industrial aluminum oxide powder were used as raw materials to prepare fused cast AZS refractories, respectively. The structure and properties of the two fused cast AZS refractories were compared and analyzed by lithofacies analysis, X-ray diffraction analysis, and energy dispersive spectroscopy analysis, etc. The results indicate that fused cast AZS refractory material prepared by ordinary industrial aluminum oxide powder has the incomplete conversion γ-Al2O3, which leads to uneven distribution of Al2 O3-ZrO2 eutectic. The alumina phase in the fused cast AZS refractory prepared by calcined alumina oxide powder is α-Al2O3. The fused cast AZS refractory prepared by calcined aluminum oxide has less baddeleyite, more Al2O3-ZrO2 eutectic and more uniform distribution of glass phase. The distribution of crystal structure affects amount of glass phase exudation and corrosion resistance to molten glass. The glass phase exudation of the fused cast AZS refractory prepared by calcined aluminum oxide powder is 0. 57 percentage points lower than that of fused cast AZS refractory prepared by ordinary industrial aluminum oxide powder. The corrosion resistance to molten glass of fused cast AZS refractory prepared by calcined aluminum oxide power is 0. 15 mm/24 h higher than that of fused cast AZS refractory prepared by ordinary industrial aluminum oxide power. [ABSTRACT FROM AUTHOR]

Chaetominine (CHA), an alkaloid with a biological activity obtained from Aspergillus fumigatus CY018, has strong anticancer activity against the human leukemia cells. However, its physiological and biochemical research is limited by CHA yield in the liquid‐state fermentation, which is a problem that urgently needs effective biological solution. In this work, Ca2+ and Al3+ were found to have a strong promoting effect on CHA production after multiple metal ions screening. Then, the addition condition of Ca2+ and Al3+ was, respectively, optimized CHA production and dry cell weight. The intermediate metabolites were increased with coaddition of Ca2+ and Al3+. The activities of key enzymes of DAHPs, AroAs, and TrpCs in the CHA biosynthesis pathway were improved by 3.58‐, 3.60‐, and 3.34‐fold, respectively. Meanwhile, the transcription level of laeA, dahp, cs, and trpC was upregulated by 3.22‐, 12.65‐, 5.58‐, and 6.99‐fold, respectively, by coaddition of Ca2+ and Al3+. Additionally, the fermentation strategy was successfully scaled up to a 5‐L bioreactor, in which CHA production could attain 75.6 mg/L at 336 h. This work demonstrated that Ca2+ and Al3+ coaddition was an effective strategy for increasing CHA production, and the information obtained might be useful in the fermentation of filamentous fungi with the addition of metal ions. [ABSTRACT FROM AUTHOR]

Naoxintong capsule (NXT) is one of the most prevalent Traditional Chinese Medicine formulations in the treatment of coronary heart disease (CHD), yet the action of pharmacodynamic components remains unclear. To determine the basis by which pharmacodynamic components of NXT may be effective in the treatment of CHD. The protective effect of NXT (0.01–100 μg/mL) on 293 T and hy926 cells was determined by MTT assay for 24 h. Afterwards, to investigate the pharmacodynamic material basis of NXT in anti-inflammatory and antioxidant effects, based on previous UPLC/Q-TOF analysis, 293 T and hy926 cells were divided into control (treated with solvent), model (incubated with TNF-α, LPS or H2O2), intervention (treated with UPLC components) and positive groups. After 24 h of treatment, all cells were tested to verify the screening results. MOE software was applied to dock bioactive compounds with phosphoinositide 3-kinase (PI3K), then the protein expression and phosphate levels were determined by western blotting. NXT could significantly inhibit the expression of NF-κB, MMP-9 and NO in cells with IC50 values of 0.1178, 0.1182 and 0.1094 μg/mL. Based on the screening results, six components of NXT were identified (calycosin, ferulic acid, salvianolic acid B, ononin, salvianolic acid E, and salvianolic acid F) which can inhibit NF-κB, MMP-9, and NO simultaneously, while exerting cytoprotective effects by inhibiting the activation of the PI3K/AKT pathway under different conditions by virtue of their advantageous interaction with PI3K. These ingredients have outstanding therapeutic potential and may provide a scientific basis for the future application and research of NXT. [ABSTRACT FROM AUTHOR]

Cordyceps militaris, Chinese traditional medicinal fungus, has many bioactive properties. Cordycepin (3'-deoxyadenosine) is a major bioactive component of C. militaris. Various methods can significantly elevate cordycepin production, which suggests a diverse set of metabolic regulatory mechanisms. Thus, we aimed to identify transcription factors that regulate cordycepin biosynthesis pathways. Transcriptome analysis of wild-type C. militaris, C. militaris GYS60, a cordycepin high-producing strain, and C. militaris GYS80, a low-producing strain, were used to measure expression and function of genes related to cordycepin biosynthesis. The transcriptome expression data were confirmed by quantitative real-time polymerase chain reaction. We identified 155 relevant transcription factors in 19 families that included Fork head/winged helix factors, other C4 zinc finger-type factors, C2H2 zinc finger factors, tryptophan cluster factors, nuclear receptors with C4 zinc fingers, homeodomain factors, and Rel homology region factors. Energy generation and amino acid conversion pathways were activated in GYS60 so that abundance of cordycepin precursors was increased. Genes and transcription factors for rate-limiting enzymes in these pathways were identified. Overexpression of two key transcription factors, Kruppel-like factor 4 (Klf4) and Retinoid X receptor alpha (Rxra), promoted high cordycepin production in GYS60. In GYS60, Klf4 and Rxra were responsible for upregulation of genes in cordycepin biosynthesis, namely an oxidoreductase, 3',5'-cyclic AMP phosphodiesterase, a transferase, and adenylate cyclase. Upregulation of these genes increased 3'-AMP content, thereby elevating cordycepin synthesis.

The production efficiency of microbial cell factory is determined by the growth performance, product synthetic capacity, and stress resistance of the strain. Strengthening the stress resistance is the key point to improve the production efficiency of microbial cell factory. Tolerance engineering is based on the response mechanism of microbial cell factory to resist stress. Specifically, it consolidates the cell wall-cell membrane barrier to enhance the defense against stress, accelerates the stress response to improve the damage repair, and creates tolerance evolutionary tools to screen industrial microorganisms with enhanced robustness. We summarize the regulation strategies and forecast the prospects of tolerance engineering, which plays an important role in the microbial cell factories for sustainable production of natural products and bulk chemicals.