Tertiary treatment of municipal wastewater in an IBFR dominated by PD/A with unique niche.

To explore the feasibility of biofilter reactor to treat municipal secondary effluent deeply without extra carbon source, this paper proposed an integrated biofilter reactor (IBFR) coupling partial denitrification (PD) with anammox (A) to treat the secondary effluent and raw sewage with the flow ratio of 3:1 together. The results show that the effluent concentration of TN and COD in IBFR could be reduced to 10 mg/L and 15 mg/L, respectively, under hydraulic retention time of 1.5 h and nitrogen loading rate of 0.55 kg/(m3·d). The highest specific anammox activity (19.2 mg N/(g TVS·d)) and the maximum extracellular polymeric substance (EPS) content (107.21 mg/g TVS) occurred at the 25-50 cm section of IBFR, where Thauera, Candidatus Anammoximicrobium and Candidatus Brocadia were the dominant denitrifiers and anammox bacteria. Furthermore, the cyclic self-stratification occurred along the reactor height, where the utilization, decomposition, transformation and cross-feeding of EPS enhanced the performance stability of nitrogen and carbon removal, strengthened the niche structure and promoted the synergistic symbiosis. In conclusion, IBFR coupling PD and A demonstrated the possibility to treat secondary effluent without additional carbon sources, which is expected as an alternative approach for tertiary treatment of municipal wastewater.

Partial substitution of wheat flour with soybean and gluten powder: impact on flavor characteristics of Pixian Douban-Meju and its quality.

BACKGROUND: In this study, different proportions of soybean flour and gluten flour were used as partial replacements for wheat flour for the fermentation of Pixian Douban-Meju (PXDB). The aim was to study the effects of soybean flour/gluten flour on the quality improvement of PXDB. RESULTS: In comparison with the control group (CT) (0% substitution of wheat flour), substitution of wheat flower with 12.5% soybean flour (the H2 group), 7.5% gluten flour (G2), and 10% gluten flour (G3) improved the amino acid nitrogen content by 3.8%, 5.6%, and 9.4% respectively. The mixtures of wheat flour and gluten flour (G2 or G3) increased the organic acid and free amino acid content. The results of two-dimensional gas chromatography mass spectrometry (GC × GC-MS) showed that the amount of key aroma substances increased about sixfold in comparison with the CT group (194.61 g.kg-1 ), achieving 1283.67, 1113.883, and 1160.19 g.kg-1 in the H2, G2, and G3 groups, respectively. There were also more aldehydes and pyrazines in all the substitution groups. Quantitative descriptive analysis indicated that the G3 sample presented the best organoleptic quality with a reddish-brown color and a more mellow aroma than the control sample. CONCLUSION: In conclusion, the fermentation of G3 resulted in higher quality PXDB-meju, showing that partial substitution of wheat flour with gluten improved the quality of PXDB. © 2023 Society of Chemical Industry.

The effect of genetic variation and mRNA expression of interleukin-17A gene on susceptibility to asthma.

Analyzing the genetic variation and mRNA expression of interleukin-17A (IL-17A) gene and its impact on asthma susceptibility was the purpose of this study. 120 asthma patients were selected as the asthma group, and another 120 healthy individuals who underwent physical examination were selected as the health group; Compare the cytokine levels and mRNA expression of IL-17A between two groups, as well as the clinical indicator total immunoglobulin E (TIgE) levels; The genotype and allele distribution frequency of IL-17A Single-nucleotide polymorphism locus rs2275913 and rs8193036 were compared between the two groups; Compare the serum IL-17A and TIgE levels of different genotypes at rs2275913 and rs8193036 loci; and logistic regression was used to evaluate the impact of IL-17A on asthma susceptibility. The serum levels of IL-17A, TIgE, and IL-17AmRNA expression in the asthma group were higher than those in the healthy group (P<0.05). There were three genotypes of AA, AG and GG at rs2275913 locus, and the frequency distribution between the two groups was significant (P<0.05), and the frequency of A Allele frequency in asthma group was higher than that in healthy group (P<0.05). There are three genotypes of CC, CT, and TT at the rs8193036 locus, and there was no significant difference in the frequency distribution between the two groups (P>0.05). There is no difference in the frequency distribution of alleles C and T between the two groups (P>0.05). The levels of IL-17A and TIgE in the rs2275913AA genotype were higher than those in the AG and GG genotypes (P<0.05); There was no difference in IL-17A and TIgE levels among different genotypes of rs8193036 (P>0.05). The rs2275913 polymorphism was associated with asthma susceptibility and is an independent risk parameter for asthma susceptibility. Upregulation of serum IL-17A and TIgE, as well as overexpression of IL-17A mRNA, were closely related to asthma susceptibility in asthma patients. The rs2275913 polymorphism had a significant role in increasing the risk of asthma, and variant allele A may be a susceptibility factor for increasing asthma risk.

Enhancing viability of dried lactic acid bacteria prepared by freeze drying and spray drying via heat preadaptation.

Physical injury carried by dried process was an inevitable and hostile problem which could seriously affect the quality and viability of microbial agents. In this study, heat preadaptation was successfully applied as a pretreatment to fight against the physical stresses encountered during freeze-dried and spray-dried process and develop a high activity Tetragenococcus halophilus powder. The results indicated T. halophilus cells maintained a higher viability in dried powder when cells were treated with heat preadaptation before dried process. Flow cytometry analysis illustrated that heat preadaptation contributed to maintain a high membrane integrity during dried process. Besides, glass transition temperatures of dried powder increased when cells were preheated, which further verified that higher stability was obtained in group preadaptation during shelf life. Additionally, dried powder prepared by heat shock presented a better fermentation performance, suggesting heat preadaptation may be a promising strategy to prepare bacterial powder by freeze drying or spray drying.

Comprehensive Transcriptomic Analysis of Heterotrophic Nitrifying Bacterium Klebsiella sp. TN-10 in Response to Nitrogen Stress.

Klebsiella sp. TN-10, a heterotrophic nitrifying bacterium, showed excellent nitrification ability under nitrogen stress. The strain was cultured under different nitrogen stress levels, including ammonium sulfate 0.5, 2.5, and 5 g/L, and samples were titled group-L, group-M, and group-H, respectively. In these three groups, the removed total nitrogen was 70.28, 118.33, and 157.18 mg/L after 12 h of cultivation, respectively. An RNA-Seq transcriptome analysis was used to describe key regulatory networks in response to nitrogen stress. The GO functional enrichment and KEGG enrichment analyses showed that differentially expressed genes (DEGs) participated in more pathways under higher nitrogen stress (group-H). Carbohydrate metabolism and amino acid metabolism were the most abundant subcategories, which meant these pathways were significantly influenced by nitrogen stress and could be related to nitrogen removal. In the nitrogen cycle, up-regulated gene2311 (narK, encodes major facilitator superfamily transporter) may accelerate the entry of nitrogen into the cells and subsequently contribute to the nitrogen utilization. In addition, the up-regulation of gene2312 (narG), gene2313 (narH), and gene2315 (narH) may accelerate denitrification pathways and facilitate nitrogen removal. The results presented in this study may play a pivotal role in understanding the regulation networks of the nitrifying bacterium TN-10 under nitrogen stress.

Application of Gastroscopy Based on Nano Carbon in the Remedy of Chronic Pulmonary Heart Disease Caused by Helicobacter Pylori.

Chronic pulmonary heart disease is a common respiratory disease. Helicobacter pylori infection can lead to the occurrence of chronic pulmonary heart disease. However, most drugs for chronic pulmonary heart disease caused by helicobacter pylori are lack of tissue specificity. At the same time, due to the blocked blood circulation in the ischemic area, the distribution of drugs in the ischemic area is often not ideal. The gastroscope technology of nano carbon can make the drug release in the focus as much as possible, and can achieve the goal of targeted treatment. This paper mainly studies the application of the gastroscope technology based on nano carbon in the remedy of chronic pulmonary heart disease caused by helicobacter pylori. After 8 weeks of treatment, the indexes of right heart function in the two groups: TAPSE and RVMPI were better than before treatment, and the improvement degree in the remedy group was more obvious than that in the control group (P < 0.05). The improvement degree of E/A and PASP was not statistically significant, the difference between the two groups was not significant (P > 0.05). In addition, the gastroscope of nano carbon can also reduce UA and TG in blood. The overall response rate was 93.75% in the remedy group, which was higher than that in the control group (P < 0.05).

Comparative experiments of fibril formation from whey protein concentrate with homogeneous and secondary nuclei.

Two types of special structures, homogeneous and secondary nuclei, form during fibril formation. The structural and functional properties of amyloid fibrils in whey protein concentrate (WPC) with different ratios of added homogeneous nuclei to secondary nuclei were investigated. Thioflavin T fluorescence analysis and kinetic equations indicated that two types of nuclei could accelerate WPC fibrillation compared with WPC self-assembling into amyloid fibrils, thereby reducing the lag time and increasing the number of fibrils. However, there were considerable differences in the nucleation-inducing capability of WPC fibrillation between homogeneous and secondary nuclei. The number of fibrils formed by adding homogeneous nuclei was higher than that obtained with secondary nuclei, the increase in the Th T fluorescence intensity induced by homogeneous nuclei was 1.83-fold much than secondary nuclei. Meanwhile, secondary nuclei yielded a 2.71-fold faster aggregation rate of WPC than homogeneous nuclei, particularly during the first hour of thermal treatment (protein mass ratio of nuclei to WPC 1:1). The gelation time of WPC after secondary nuclei addition was shorter, from 10 h (WPC (2.0/6.5)) to 4 h (WPC + HN) to 2 h (WPC + SN); however, the gel microstructure of WPC after the addition of homogeneous nuclei was denser, yielding a preferred water holding capacity.

The structure and amphipathy characteristics of modified γ-zeins by SDS or alkali in conjunction with heating treatment.

γ-Zein was modified by SDS or alkali combined with heating treatments in water and in 70% ethanol to change its amphipathic properties and explore the relationship between amphipathic characteristic and structure. γ-Zein water-dispersibility was dramatically increased via alkali or SDS combined with heating treatments, but their ethanol-dispersibilities were significantly different during ethanol evaporation. High both water-dispersibility and ethanol-dispersibility were found from alkali modified γ-zein while high water-dispersibility but low ethanol-dispersibility were obtained from SDS modified γ-zein, indicating that alkali modified γ-zein had better amphipathic characteristic compared with SDS modified γ-zein. Alkali modified γ-zein with higher amphipathic characteristic possessed higher structural inversion ability since it was easy to recover its native state as solvent changing from water to ethanol, contrary to SDS modified γ-zeins whose amphipathic characteristic was not improved. Moreover, the higher structural inversion ability of alkali modified γ-zein depended on the recovery capability of α-helix structure as solvent altering.

Acid-responsive properties of fibrils from heat-induced whey protein concentrate.

The heat-induced fibrils of whey protein concentrate (WPC) have demonstrated an acid-responsive property; that is, the fibrils went through formation-depolymerization-reformation as pH was adjusted to 1.8, 6.5, and back to 1.8. We investigated the microstructure, driving force, and thermal stability of 3.0% (wt) WPC nanofibrils adjusted between pH 6.5 and 1.8 twice. The results showed that the nanofibrils had acid-responsive properties and good thermal stability after reheating for 10h at 90°C and adjusting pH from 1.8 to 6.5 to 1.8. The content of WPC fibril aggregates was not much different with the prolongation of heating times during pH variation. Although the nanofibrils' structure could be destroyed only by changing the pH, the essence of this destruction might only form fiber fragments, polymers that would restore a fibrous structure upon returning to pH 1.8. A described model for the acid-responsive assembly of fibrils of WPC was proposed. The fibrils went through formation-depolymerization-reformation by weaker noncovalent interactions (surface hydrophobicity) as pH changed from 1.8 to 6.5 back to 1.8. However, the fibrils lost the acid-responsive properties because much more S-S (disulfide) formation occurred when the solution was adjusted to pH 6.5 and reheated. Meanwhile, fibrils still possessed acid-responsive properties when reheated at pH 1.8, and the content of fibrils slightly increased with a further reduction of α-helix structure.