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Lipopolysaccharide (LPS) is an important pathogenic factor and plays a key role in human diseases such as fever, shock, and sepsis. Blocking the toxicity of LPS through antagonism is considered the best choice for the treatment of LPS-induced diseases. In this research, nucleic acid aptamer LA27, which was previously selected and optimized by our group, was used as an LPS inhibitor to treat human HepG2 cells stimulated by LPS from four different sources (StLPS, EcoliLPS, PaLPS, and SeLPS): the levels of expression of three inflammatory cytokines factors (TNF-α, IL-1β, and IL-6) were evaluated by ELISA on LA27-treated and untreated cells incubated for 12 h with LPS. The results of the assays indicated that LA27 exhibited considerable anti-inflammatory activity. The binding site and interactions between aptamer LA27 and LPSs were also simulated using Molecular Operating Environment (MOE) 2018 software. MOE simulation results showed that, under a combination of the hydrophobic interaction, hydrogen bonding, and electrostatic interactions, the fatty acid chain of LPS could interact with the wide hydrophobic region of the aptamer, constituting its major groove, and formed stable complex of T-type. The present research indicated that LA27 might be a potential therapeutic agent for sepsis and other diseases, which provides a new path for the development of LPS antagonists.

γ-aminobutyric acid is a nonprotein amino acid that accumulates in plants under stress. Abscisic acid is important for stress regulation via modulation of γ-aminobutyric acid function. Our results show that the expression of glutamate decarboxylase but not diamine oxidase gene is upregulated in germinating soybean treating treated with exogenous abscisic acid. There was a concomitant increase in glutamate decarboxylase and diamine oxidase activities and putrescine and spermine contents with a decrease in glutamate. These changes were abrogated by fluridone, an inhibitor of abscisic acid synthesis. In conclusion, abscisic acid treatment increases γ-aminobutyric acid accumulation by upregulating diamine oxidase gene expression and activation of glutamate decarboxylase and diamine oxidase activity in germinating soybean under hypoxia-salt stress.

Gamma-aminobutyric acid (GABA), a nonproteinous amino acid with some benefits on human health, is synthesized by GABA-shunt and the polyamine degradation pathway in plants. The regulation of Ca2+ and aminoguanidine on GABA accumulation in germinating soybean (Glycine max L.) under hypoxia-NaCl stress was investigated in this study. Exogenous Ca2+ increased GABA content significantly by enhancing glutamate decarboxylase gene expression and its activity. Addition of ethylene glycol tetra-acetic acid into the culture solution reduced GABA content greatly due to the inhibition of glutamate decarboxylase activity. Aminoguanidine reduced over 85% of diamine oxidase activity, and 33.28% and 36.35% of GABA content in cotyledon and embryo, respectively. Under hypoxia–NaCl stress, the polyamine degradation pathway contributed 31.61–39.43% of the GABA formation in germinating soybean.

Alpha-lipoic acid (ALA), a naturally occurring compound, exerts powerful protective effects in numerous cardiovascular disease models. However, the pharmacological property of ALA on cardiac hypertrophy has not been well investigated. The present study was carried out to determine whether ALA exerts a direct anti-hypertrophic effect in cultured cardiomyocytes and whether it modifies the hypertrophic process in vivo. Furthermore, we determined the potential underlying mechanisms for these actions. Treatment of cardiomyocytes with phenylephrine (PE) for 24 h produced a marked hypertrophic effect as evidenced by significantly increased in ANF and BNP mRNA levels, as well as cell surface area. These effects were attenuated by ALA in a concentration-dependent manner with a complete inhibition of hypertrophy at a concentration of 100 µg/mL. PE-induced cardiomyocyte hypertrophy was associated with increased mRNA and protein levels of C/EBPβ, which were inhibited by pretreatment with ALA. However, when cardiomyocytes were co-transfected with C/EBPβ, ALA failed to inhibit hypertrophic responses. Upregulation of C/EBPβ expression was also evident in rats subjected to 4 weeks of coronary artery ligation (CAL). However, rats treated with ALA demonstrated markedly reduced hemodynamic and hypertrophic responses, which were accompanied by attenuation of upregulation of C/EBPβ. Taken together, our results revealed a robust anti-hypertrophic and anti-remodeling effect of ALA, which is mediated by inhibition of C/EBPβ activation.

High levels of γ-aminobutyric acid (GABA) accumulate in plant tissues under various stresses and exogenous additives. The purpose of this research is to provide an effective finding that can prove a rapid accumulation of GABA in germinated soybean (Glycine max L.) in response to different additives under hypoxia. Hypoxia-induced GABA accumulation in soybean embryo resulted in part from polyamine oxidation. Response to different concentration of glutamate (Glu), pyridoxal phosphate, arginine, CuCl2, NaCl, and CaCl2, a significant difference including GABA accumulation, changes of Glutamate decarboxylase (GAD), and Diamine oxidase activity (DAO) activity in germinated soybean under hypoxia occurred (p

Effects of soaking temperature, soaking time, opportunity of aeration treatment, culture temperature, pH value, and air flow rate on γ-aminobutyric acid (GABA) accumulation during germination of soybean (Glycine max (L.) Merr.) were investigated in this study. The objective of this study was to optimize the culture conditions of GABA production in germinated soybeans. Results showed that soaking at 30 °C for 4 h was found to be the most effective soaking ways that made soybean seeds have sufficient moisture, satisfactory germination, and GABA accumulation. The suitable stress opportunity was dark culture for 2 days with distilled water and then hypoxia stress in aerated culture medium for 2 days in a dark incubator at 30 °C. Under these conditions, the maximum GABA content (2.24 mg/g DW) was 3.5 times higher than the initial sample of aeration treatment (0 h) and 12.5 times higher than the raw material. Correlation analysis also revealed that GABA accumulation was significantly correlated to the corresponding physiochemical indexes (p < 0.01). Box-Behnken experimental analysis showed that the optimal condition with aeration treatment for GABA accumulation in germinated soybean was at a temperature of 30.5 °C, a pH value of 4.1, and an air flow rate of 0.9 L/min; the predicted highest GABA yield was 2.60 mg/g DW, which was 15.2 times higher than raw seeds. Analysis of variance and confirmatory trials for the regression model suggested that the model can quite exactly predict GABA accumulation in soybean during germination.

Reduced glutathione (GSH) from fermentation broth of Saccharomyces cerevisiae was extracted with ethanol without disruption of the cells. The effects of ethanol concentration, extraction temperature and extraction time were assessed by using 2(3) full factorial designs (FFD). Preliminary studies showed that ethanol concentration had the most influence on GSH yield by ethanol extraction, based on the first order regression coefficients derived using MINITAB software, and an optimal ethanol concentration (25%, v/v) was obtained. However, compared to the conventional extraction technique (hot water extraction), there was no significant advantage in yield of GSH from yeast cells using ethanol extraction under these optimized conditions. But ethanol extraction has several advantages, such as lower energy consumption and lower protein concentration of extraction broth, which may reduce the complexity and cost of the purification process. Hence, ethanol extraction which does not disrupt yeast cells could be an inexpensive, simple and efficient alternative to conventional extraction techniques in the GSH industry.

An on-line monitoring of viable-cell mass in high-cell-density fed-batch cultivations of Saccharomyces cerevisiae grown on an industrial complex medium was performed with an in situ capacitance probe fitted to a 50-l fermentor. Conventional off-line biomass determinations of several parameters, including dry cell weight (DCW), optical density at 600 nm wavelength (OD(600)), packed mycelial volume (PMV) and number of colony forming units (CFU), were performed throughout the bioprocess and then compared with on-line viable-cell concentrations measured using a capacitance probe. Capacitance versus viable biomass and all off-line biomass assay values were compared during glutathione fermentation in industrial complex culture media. As a result, the relationship between the number of colony forming units and capacitance with a correlation coefficient (R) of 0.995 was achieved. Simultaneously, compared with those determined by at-line indirect estimation methods including oxygen uptake rate (OUR) and carbon dioxide evolution rate (CER), the specific growth rates estimated by on-line capacitance measurement could be more reliable during glutathione fermentation. Therefore, it is concluded that a capacitance probe is a practical tool for real-time viable biomass monitoring in high-cell-density fed-batch cultivation in a complex medium.

The objective of the study is to investigate the effects of chronic aluminum overload on rat liver function and its induction of pathological changes in metal ion levels and oxidative stress in hepatic tissues. Wistar rats were intragastrically administered aluminum gluconate (200 mg Al(3+)/Kg) once a day, 5 days a week, for 20 weeks. HE staining was used to visualize pathological changes in rat liver tissue. A biochemical method was adopted to detect ALT, AST, ALP, and GGT levels, as well as liver SOD activity and blood plasma MDA content. A plasma atomic emission spectrophotometer was used to detect Al, Mn, Fe, Zn, and Cu ion contents in liver tissue. Our results showed obvious vacuolar degeneration, granular degeneration, and spotty necrosis in chronic Al-overload rat hepatocytes. The levels of ALT, AST, ALP, and GGT were significantly increased. Liver SOD activity was significantly decreased, and MDA content was significantly increased. In Al-overload rat liver, Al, Mn, Fe, and Cu contents were significantly increased, and in Al-overload rat serum, Mn, Fe, Zn, and Cu contents were significantly decreased. However, the Al level in Al-overload rat serum was not significantly different from that in control rat serum. These results suggest that chronic aluminum overload causes obvious damage to rat liver and causes imbalances in Al, Mn, Fe, Zn, and Cu levels in rat liver and serum. Metal ion imbalance-related oxidative stress may be involved in the mechanism of chronic liver injury caused by aluminum overload.

Improvement of microbial strains for the high-production of industrial products has been the hallmark of all commercial fermentation processes. Strain improvement has been conventionally achieved through mutation and selection. However, most of the screenings were performed in shake flasks, which made the screening procedure very complex, time-consuming, and inefficient. Most mutant spore suspension had no chance to be screened due to the low-throughput of shake flasks and had to be sacrificed. In this paper, in order to get a Cephalosporin C (CPC) high-yield stain, traditional mutagenesis was employed to obtain the mutant library and gave them the equal screening chance by a novel mixture culture method combined with high-throughput screening method. The good correlation of fermentation results between differing-scale cultivations confirmed the feasibility of utilizing the 48-deep microtiter plates as a scale-down tool instead of shake flasks for culturing high-aerobic microbes with long cultivation period. The microbioassay based on the antibacterial activity of CPC against Alcaligenes faecalis was used to select mutants. As a result, the high-yield strain W-6 was successfully screened out and the CPC titer was nearly 50 % higher than that of the parental strain in the shake flask. The CPC production of strain W-6 was further validated in 50 l bioreactor, and the CPC production reached 32.0 g/l, twofold higher than that of the wild strain.