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Qi Xin,1 Tonghui Xie,1 Rui Chen,1 Xing Zhang,1 Yingmu Tong,1 Hai Wang,1 Shufeng Wang,2 Chang Liu,1,3 Jingyao Zhang1,3 1Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, 710061, People’s Republic of China; 2Department of General Surgery, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, 710061, People’s Republic of China; 3Department of SICU, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, 710061, People’s Republic of ChinaCorrespondence: Chang Liu; Jingyao Zhang, Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, 710061, People’s Republic of China, Tel +86-29-85323900, Fax +86-29-85324642, Email liuchangdoctor@163.com; you12ouy@163.comBackground: Sepsis-induced acute kidney injury (S-AKI) is associated with systemic inflammatory responses and coagulation system dysfunction, and it is associated with an increased risk of mortality. However, there was no study to explore the predictive value of inflammatory and coagulation indicators for S-AKI.Methods: In this retrospective study, 1051 sepsis patients were identified and divided into a training cohort (75%, n = 787) and a validation cohort (25%, n = 264) in chronological order according to the date they were admitted. Univariate analyses and multivariate logistic regression analyses were performed to identify the independent predictors of S-AKI. The logistic regression analyses (enter methods) were used to conducted the prediction models. The ROC curves were used to determine the predictive value of the constructed models on S-AKI. To test whether the increase in the AUC is significant, we used a two-sided test for ROC curves available online (http://vassarstats.net/roc_comp.html). The secondary outcome was different AKI stages and major adverse kidney events within 30 days (MAKE30). Stage 3B of S-AKI was defined as both meeting the stage 3 criteria [increase of Cr level by > 300% (≥ 4.0 mg/dL with an acute increase of ≥ 0.5 mg/dL) and/or UO < 0.3 mL/kg/h for > 24 h or anuria for > 12 h and/or acute kidney replacement therapy] and having cystatin C positive. MAKE30 were a composite of death, new renal replacement therapy (RRT), or persistent renal dysfunction (PRD).Results: We discovered that cardiovascular disease, white blood cell (WBC), mean arterial pressure (MAP), platelet (PLT), serum procalcitonin (PCT), prothrombin time activity (PTA), and thrombin time (TT) were independent predictors for S-AKI. The predictive value (AUC = 0.855) of the simplest model 3 (constructed with PLT, PCT, and PTA), with a sensitivity of 77.6% and a specificity of 82.4%, had a similar predictive value comparing with the model 1 (AUC = 0.872) and the model 2 (AUC = 0.864) in the training cohort (P > 0.05). Compared with the model 1 (AUC = 0.888) and the model 2 (AUC = 0.887), the model 3 (AUC = 0.887) had a similar predictive value in the validation cohort. Moreover, model 3 had the best predictive power for predicting S-AKI in the stage 3 (AUC = 0.777), especially in stage 3B (AUC = 0.771). Finally, the model 3 (AUC = 0.843) had perfect predictive power for predicting MAKE30 in sepsis patients.Conclusion: Within 24 hours after admission, the simplest model 3 (constructed with PLT, PCT, and PTA) might be a robust predictor of the S-AKI in sepsis patients, providing information for timely and efficient intervention.Keywords: inflammation, coagulation, prediction model, sepsis, acute kidney injury

Background. Sepsis-related acute kidney injury (S-AKI) is a frequent complication of hospitalized patients and is linked to increased morbidity and mortality. Early prediction and detection remain conducive to optimizing treatment strategies and limiting further insults. This study was aimed at evaluating the potential predictive value of the combined prognostic nutrition index (PNI) and neutrophil-to-lymphocyte ratio (NLR) to predict the risk of AKI in septic patients. Methods. In this retrospective study, 1238 adult patients with sepsis who were admitted to the First Affiliated Hospital of Xi’an Jiaotong University from January 2015 to June 2021 were enrolled. Patients were divided into two groups: the non-AKI group ( n = 731 ) and the S-AKI group ( n = 507 ). Univariate and multivariate logistic regression analyses were performed to screen the independent predictive factors of S-AKI. A receiver operating characteristic (ROC) curve was used to evaluate the predictive value of PNI and NLR. Results. Multivariate logistic regression analysis indicated that age, chronic liver disease, cardiovascular disease, respiratory rate (RR), white blood cells (WBC), blood urea nitrogen (BUN), creatinine (CRE), international normalized ratio (INR), neutrophil-to-lymphocyte ratio (NLR), and prognostic nutrition index (PNI) were independent prognostic factors of S-AKI. In the three models, the adjusted OR of PNI for S-AKI was 0.802 (0.776-0.829), 0.801 (0.775-0.829), and 0.717 (0.666-0.772), while that of NLR was 1.094 (1.078-1.111), 1.097 (1.080-1.114), and 1.044 (1.016-1.072), respectively. In addition, the area under the ROC curve of the PNI plus NLR group was significantly greater than that of the CRE plus BUN group (0.801, 95% CI: 0.775-0.827 vs. 0.750, 95% CI: 0.722-0.778, respectively; P < 0.001 ). Conclusions. PNI and NLR have been identified as readily available and independent predictors in septic patients with S-AKI. PNI, in combination with NLR, is of vital significance for early warning and efficient intervention of S-AKI and is superior to combined BUN and CRE.

The performance of microalgae-based wastewater treatment processes for ammonium-N (NH4+-N) removal depends on the maintenance of a favorable pH that is critical for minimizing nitrogen escape in the form of free ammonia (NH3) and preventing high-NH3 or extreme-pH stress. This study developed a CO2-inorganic carbon (CO2-IC) buffering system that automatically stabilized pH with the supply of a carbon source for efficient photosynthetic reclamation of NH4+-N by a euryhaline microalga Tetraselmis subcordiformis. The soluble (NaHCO3) and insoluble (CaCO3 and MgCO3) ICs were compared for this purpose. The pH was well controlled in the range of 6.5~8.5 in the CO2-IC system, which was suitable for the photosynthetic growth of T. subcordiformis. The NH4+-N (100 mg/L) was almost completely removed in three days, with the maximum removal rate of 60.13 mg N/L/day and minimal N escape of 19.65% obtained in the CO2-NaHCO3 system. The CO2-IC system also restricted the release of extracellular organic matter by preventing stress conditions. The CO2-NaHCO3 system enabled the highest “normal” starch production suitable for fermentation, while the CO2-CaCO3/MgCO3 system facilitated high-amylose starch accumulation that was conducive to producing bio-based materials and health-promoting ingredients. The proteins accumulated in T. subcordiformis were of good quality for animal feeds.

Sepsis-related liver injury (SRLI) is a common condition in critically ill patients, and it is associated with poor outcomes. Early identification of liver injury in sepsis can provide clinicians withthe abundance of information for optimizing treatment strategies and improve quality of life. Therefore, the purpose of this study was to establish a predictive model to assess the early predictive value of liver injury in sepsis.In this retrospective study, a total of 1116 patients with sepsis enrolled from the Biobank of First Affiliated Hospital of Xi'an Jiaotong University were included. According to the diagnosis of SRLI, all patients were divided into SRLI group and sepsis group. Multivariable analysis was performed using stepwise logistic regression to identify the independent risk factors of SRLI. Based on the results of multivariate regression analysis, we constructed a prediction model. The receiver operating characteristic curve (ROC) was used to determine the predictive value of the model on SRLI.From December 2015 to December 2021,1116 cases met the inclusion criteria and were included in this study. The median age was 58 years, of which 458 (41.04 %) were female. We discoveredthat procalcitonin (PCT), AST-to-platelet ratio index (APRI), alanine aminotransferase (ALT), lactate (Lac), blood urea nitrogen (BUN), Neutrophil and Cardiovascular disease were independent predictors for SRLI. We used to enter methods for constructing the predictive model and finally found that the indicators of model 2 (AUC = 0.832) were readily available and had good predictive value for SRLI. Furthermore, we also found that model 2 (AUC = 0.763), with a sensitivity of 81.4 %, demonstrated excellent predictive value for predicting 28-day mortality in patients with septic liver injury.This study explored the risk factors of SRLI, and established a prediction model that can accurately and effectively predict the occurrence of SRLI. Furthermore, model 2 is easy to obtain and has the highest sensitivity, which can contribute to early warning and appropriate clinical decision-making.

Microalgal starch, a potential feedstock for renewable fuels and chemicals, is usually induced under stress, which hinders the simultaneous enhancement of starch content and yield. This study appli...

Background Sepsis-induced acute kidney injury (S-AKI) is a significant complication and is associated with an increased risk of mortality, especially in elderly patients with sepsis. However, there are no reliable and robust predictive models to identify high-risk patients likely to develop S-AKI. We aimed to develop a nomogram to predict S-AKI in elderly sepsis patients and help physicians make personalized management within 24 h of admission. Methods A total of 849 elderly sepsis patients from the First Affiliated Hospital of Xi’an Jiaotong University were identified and randomly divided into a training set (75%, n = 637) and a validation set (25%, n = 212). Univariate and multivariate logistic regression analyses were performed to identify the independent predictors of S-AKI. The corresponding nomogram was constructed based on those predictors. The calibration curve, receiver operating characteristics (ROC)curve, and decision curve analysis were performed to evaluate the nomogram. The secondary outcome was 30-day mortality and major adverse kidney events within 30 days (MAKE30). MAKE30 were a composite of death, new renal replacement therapy (RRT), or persistent renal dysfunction (PRD). Results The independent predictors for nomogram construction were mean arterial pressure (MAP), serum procalcitonin (PCT), and platelet (PLT), prothrombin time activity (PTA), albumin globulin ratio (AGR), and creatinine (Cr). The predictive model had satisfactory discrimination with an area under the curve (AUC) of 0.852–0.858 in the training and validation cohorts, respectively. The nomogram showed good calibration and clinical application according to the calibration curve and decision curve analysis. Furthermore, the prediction model had perfect predictive power for predicting 30-day mortality (AUC = 0.813) and MAKE30 (AUC = 0.823) in elderly sepsis patients. Conclusion The proposed nomogram can quickly and effectively predict S-AKI risk in elderly sepsis patients within 24 h after admission, providing information for clinicians to make personalized interventions.

Nitrogen-doped carbon (NC) materials have been extensively investigated for their great potential applications in adsorption, catalysis, etc. Herein, we report a facile one-step pyrolysis process for NC synthesis using abundant bio-waste of excess sludge as carbon source and cheap precursor of urea as nitrogen source. The developed materials were evaluated for organic pollutants removal through adsorption and catalytic oxidation by peroxymonosulfate (PMS) activation. Experimental results demonstrated that nitrogen doping significantly affected the elemental composition and microstructure of NC, leading to improved adsorption capability as well as PMS activation activity for methylene blue (MB) removal. The adsorption capacity for MB reached 35.831 mg g−1 over NC-700 sample (NC prepared at 700 °C). In MB catalytic oxidation experiments, effects of sample calcination temperature, catalyst dosage, PMS loading, and co-existing ions were investigated. Under optimal reaction conditions, 98.70% of MB could be removed in 20 min. Through radical quenching and electron spin resonance (ESR) tests, it was confirmed that singlet oxygen (1O2) was the main reactive species for MB degradation. Additionally, NC-700 performed well in recycle studies without significant efficiency loss. Other typical organic pollutants including malachite green (MG), methyl orange (MO), bisphenol A (BPA), phenol (PE), and sulfamethoxazole (SMX) could also be removed using NC-700 as adsorbent and catalyst. These features manifest that excess sludge-derived NC could be a promising material for organic pollutants remediation.

Lignocellulosic-like materials are potentially low-cost fermentation substrates, but their pretreatment brings about by-products. This work investigated the effects of furfural on xanthan gum (XG) production, and product quality was evaluated by structure, viscosity and antioxidant capacities. Xanthomonas campestris maintained steady polysaccharide yield (above 13 g·L–1) with enhanced cell growth at low furfural concentrations (below 3.2 g·L–1). The products were verified as XG by FT-IR, XRD, NMR and monosaccharide analysis. Moreover, they were found to have reduced acetyl, rising pyruvate and up-to-down glucuronic acid groups as increasing furfural concentration. Furthermore, XG product with 1 g·L–1 furfural addition showed the best hydroxyl scavenging effects, though reducing powers presented no variation. It was demonstrated that furfural, the common hydrolysis by-product, was not necessarily an inhibitor for fermentation, and an appropriate amount of furfural was beneficial to XG production with steady yield and good quality.

Industrial wastewaters usually possess a wide range of nitrate strength. Microalgae-based nitrate-rich wastewater treatment could realize nitrate recovery along with CO2 sequestration for sustainable biomass production, but the low tolerance of the microalgal strains to high-strength nitrate restricted the treatment process. The present study comprehensively evaluated a euryhaline marine microalga Tetraselmis subcordiformis for photosynthetic nitrate removal and biomass production in synthetic wastewater with a broad range of nitrate strength (0.24–7.0 g NO3−-N/L). This alga could acclimate to high nitrate strength up to 3.5 g NO3−-N/L (HN) without compromising biomass production. Nitrate could be completely removed within four days when low nitrate (0.24 g NO3−-N/L, LN) was loaded. The maximum nitrate removal rate of 331 mg N/L/day and specific nitrate removal rate of 360 mg N/day/g cell was obtained under medium nitrate condition (1.8 g NO3−-N/L, MN). High-nitrate stress under 7.0 g NO3−-N/L (SHN) caused an increased light energy dissipation while decreased the density of photosystem II active reaction center, which partially protect the cells from photodamage and contributed to their acclimation to SHN. The algae also enhanced amino acid/fatty acid proportions essential for maintaining intracellular redox states to cope with the stress caused by LN or SHN. HN and SHN was in favor of protein accumulation and maintenance with enhanced proportion of essential amino acids, which entitled the algal biomass to be of high quality for animal feed applied in livestock graziery and aquaculture. LN facilitated productive starch and lipid accumulation with good quality for biofuels production. The nitrate removal rate and biomass productivity exceeded most of the microalgae reported in literature under similar conditions, which highlighted Tetraselmis subcordiformis as a potent strain for flexible nitrate-rich wastewater remediation coupled with fast CO2 bio-mitigation and high-quality biomass production for sustainable algal biorefinery.

BACKGROUND: Tetracycline (TC) residues in water and soil have received wide attention due to their adverse effects on human health and ecosystem. Layer‐structured biogenic manganese oxides (BMOs) could be obtained from fungi Pleosporales sp. Y‐5 culture. Cobalt doping into BMOs (Co‐BMOs) was conducted by a facile impregnation‐calcination method to eliminate TC residues through activation of peroxymonosulfate (PMS). RESULTS: The TC in aqueous solution could be nearly completely removed in about 10 minutes under the optimal condition ([TC] = 50 mg L⁻¹, [catalyst] = 0.2 g L⁻¹, [PMS] = 0.4 g L⁻¹, 25°C). The electron paramagnetic resonance (EPR) identified the coexistence of SO₄⁻• and OH• during PMS activation. The Co‐BMOs catalyst remained great catalytic activity after five runs. Possible mechanism of PMS activation and TC degradation pathway were proposed. Preliminary biological toxicity test using green algae Chlorella vulgaris (FACHB‐8) as ecological indicator confirmed that TC degradation solution was less toxic than the original solution. CONCLUSION: This study demonstrated high catalytic activity and stability of Co‐BMOs for degradation of TC by PMS activation. The Co‐BMOs/PMS system is helpful in new efforts for TC degradation without generation of more toxic intermediates. © 2018 Society of Chemical Industry

Using food waste hydrolysate as medium for culturing oleaginous microorganism is a dual-purpose strategy for relieving environmental burdens both in food waste disposal and energy crisis. The pure culture of one oleaginous microorganism when single waste as culture media has shortages such as high operation cost, low lipid production and low substrate utilization. Mix-culture of yeast and microalgae in this work enhanced this process result in better waste treatment, higher lipid production and shorter cultivation time. Compare to pure culture of Rhodosporidium toruloides, the nitrogen utilization rate, reducing sugar utilization rate and lipid production increased by 23%, 17% and 12%, respectively, and the cultivation time shorten by 40%, in mix-culture of Rhodosporidium toruloides and Chlorella vulgaris. The results showed that the mix-culture of yeast and microalgae using food waste hydrolysate as culture medium would be a good strategy for both waste disposal and biofuel production.

Kitchen waste hydrolysis residue (KWHR), which is produced in the bioproduction process from kitchen waste (KW), is usually wasted with potential threats to the environment. Herein, experiments were carried out to evaluate the potential of KWHR as adsorbent for dye (methylene blue, MB) removal from aqueous solution. The adsorbent was characterized using FT-IR and SEM. Adsorption results showed that the operating variables had great effects on the removal efficiency of MB. Kinetic study indicated pseudo-second-order model was suitable to describe the adsorption process. Afterwards, the equilibrium data were well fitted by using Langmuir isotherm model, suggesting a monolayer adsorption. The Langmuir monolayer adsorption capacity was calculated to be 110.13 mg/g, a level comparable to some other low-cost adsorbents. It was found that the adsorption process of MB onto KWHR was spontaneous and exothermic through the estimation of thermodynamic parameters. Thus, KWHR was of great potential to be an alternative adsorbent material to improve the utilization efficiency of bioresource (KW) and lower the cost of adsorbent for color treatment.

Schwertmannite (Sch) was synthesized by Acidithiobacillus ferrooxidans and used as Fenton-like catalyst for bisphenol A (BPA) degradation combining with ultrasonic technology (US). Physicochemical characterizations showed that the bio-synthesized Sch particles had a pompon-like morphology with high BET surface area of 92.92m2/g. The degradation reaction showed a two-stage pseudo-first-order kinetic process consisting of an induction period and a followed rapid degradation period. A synergistic effect existed between US and Sch on activating H2O2 and the synergy factor was calculated to be 2.32. The catalytic efficiency of the system was mainly affected by pH, Sch dosage and temperature, but less relevant to H2O2 concentration. Free OH radicals in the bulk solution were identified to be the dominant oxidant, which were produced by both heterogeneous and homogeneous processes. The promotional effect of US on Fenton-like degradation of BPA can be ascribed to the reasons of (1) increasing the radical generation by ultrasonic cavitation; (2) reducing the apparent activation energies of degradation reaction; (3) accelerating the dissolution of iron and (4) keeping the high surface area of catalyst by continuous surface cleaning. Ecotoxicity tests indicated lower toxicities of intermediates than BPA. In addition, Sch exhibited high reusability in the recycle study.

Protein production from microalgae requires both high cell density during cultivation and high protein content in cells. Heterotrophic microalgae can achieve high cell density, and yet are confronted with the problem of low protein content. Based on over-compensation strategy, a new concentration-shift method was proposed to cultivate heterotrophic Chlorella vulgaris, aiming to increase protein content. With a prior starvation period, microalgae utilized more nitrate and accumulated more proteins compared to one-stage cultivation. Considering the convenience of operation, nitrate-added culture was adopted for producing heterotrophic microalgae, rather than sterile centrifugal culture. Operating parameters including nitrate concentration in N-deficient medium, N-starved time and nitrate concentration in N-rich medium were optimized, which were 0.18gl-1, 38h and 2.45gl-1, respectively. Under the optimized conditions, protein content in heterotrophic Chlorella reached 44.3%. Furthermore, the heterotrophic microalga was suggested to be a potential single-cell protein source according to the amino acid composition.

Kitchen waste (KW) is a worldwide issue, which can lead to environment pollution. Nevertheless, it is also a low-cost and sustainable resource for bio-production. Meanwhile, welan gum (WG) is one kind of the most important exopolysaccharide but with high material cost. The aim of this study was to adopt two-step enzymatic hydrolysis to improve the release and recovery of both sugar and protein in KW for subsequent WG production. As the results, the recovery rates of sugar and protein reached 81.07 and 77.38%, which were both satisfactory. After the conditions optimized in flasks, the welan fermentation was conducted in a 5-L fermentor, and the WG yield, utilization rates of reducing sugar and KDN, respectively, reached 5.57 g L-1, 94.25% and 61.96%. Moreover, the kinetic analyses demonstrated that the WG fermentation in KWH was a partly growth-associated process. The KW was successfully treated by fermentation for the bioconversion to WG.

Anaerobic digester effluent containing high levels of ammonia poses a threat to the environment. To hinder this issue, a modern and promising treatment method incorporates both microalgae and their bioconversion potential. When culturing Chlorella vulgaris at a 1:7 digestate supernatant dilution ratio, biomass concentration was 1.33 g L−1 and 66% of ammonia nitrogen was removed. Furthermore, a prior nitrogen-starved seed method, namely over-compensation strategy, was applied to improve both biomass production and nutrient removal. By using nitrogen-starved seeds after a 48 h nitrogen-free stimulation, biomass yield increased by 1.7-times to 2.56 g L−1. Simultaneously, ammonia nitrogen and total phosphorus removal efficiencies reached 99% and 97% respectively. The enhanced production corresponds to higher chlorophyll fluorescence in the middle and late stages of the culture. In addition, the bioproduct contained 39% carbohydrates, and the proportion of polyunsaturated fatty acids in lipids was 66%. These findings demonstrated that the over-compensation strategy contributed to greater nitrogen removal and high-value bioproduct production in the microalgae-digestate treatment system.

The study was carried out to gain insight into the effect of pretreatment on enzymatic hydrolysis of kitchen waste (KW) for xanthan fermentation. Herein, various pretreatments were applied and it was found that chemical pretreatment had positive effect on the following enzymatic or overall hydrolysis process. The highest reducing sugar concentration was obtained as 51.87g/L from 2% HCl (90°C) pretreated sample, while the Kjeldahl nitrogen (KDN) concentration was 7.79g/L. Kinetic study showed that first order kinetic model was suitable to describe the enzymatic hydrolysis process. The obtained kitchen waste hydrolysate (KWH) was successfully applied for xanthan fermentation. Xanthan concentration reached 4.09-6.46g/L when KWH with 2% HCl (90°C) pretreatment was applied as medium. In comparison, a xanthan concentration of 3.25-5.57g/L was obtained from KWH without pretreatment. Therefore, pretreatment of KW using diluted acid is favorable for the overall hydrolysis process and effective for xanthan fermentation.

BACKGROUND Food waste has great potential for biotech processing but most waste is subject to traditional disposal methods, losing its value. To alleviate economic and environmental concerns, the hydrolysate of food waste could be utilized for biolipid and protein production by Rhodosporidium toruloides Y2. RESULTS The biomass, lipid production and protein production reached 32.1 g L−1, 7.3 g L−1 and 7.0 g L−1, respectively. The composition of fatty acids and amino acids indicated that R. toruloides Y2 grown in food waste hydrolysate had the potential to be feedstock for biolipid and microbial protein production. Model prediction using the Logistic, Luedeking-Piret equation and modified Luedeking-Piret equation could estimate the growth, lipid production and reducing sugar utilization of R. toruloides Y2 in food waste hydrolysate. CONCLUSION The alternative proposed for converting food waste into microbial biomass is applicable. Food waste hydrolysate is suitable for lipid and protein production by R. toruloides Y2, without any additional nutrition or detoxification procedure. © 2016 Society of Chemical Industry

Nanostructured manganese oxide materials were prepared from manganese-contained wastewater (MW) using a facile hydrothermal method and adopted as a catalyst to degrade phenol via activation of peroxymonosulphate (PMS). In the WM environment, δ-MnO

Ganoderma lucidum polysaccharides (GLP) as one of water-soluble polysaccharides has attracted much attention because of its bioactivities, especially antioxidant activity. Deproteinization is an essential step in the purification process of polysaccharides. In this study, three classic deproteinization methods, including neutral protease method, TCA precipitation and CaCl2 salting out, were evaluated for crude GLP processing. The methods had ability to remove proteins (71.50–87.36%), and meanwhile polysaccharide loss (8.35–11.39%) was observed. Structure analysis indicated that these deproteinization methods had no significant effect (p > 0.05) on molecular weight of polysaccharides, but led to varying degrees of glycoside bond losses (1.14–64.05%). Moreover, the antioxidant activities of deproteinized polysaccharides were measured in vitro by hydroxyl radical, reducing power, 2, 2-diphenyl-1-picryl-hydrazyl (DPPH) free radical and ferric-reducing antioxidant power tests. Purified GLP by enzymolysis maintained the strongest antioxidants activities with the retention rate of over 47.40%, and its deproteinization efficiency and polysaccharide loss ratio were 74.03% and 11.39% respectively. In view of relatively high purity and antioxidant activity, enzymolysis was a suitable deproteinization method for GLP production.

Interaction between ulipristal acetate (UPA) and human serum albumin (HSA) was investigated in simulated physiological environment using multi-spectroscopic and computational methods. Fluorescence experiments showed that the quenching mechanism was static quenching, which was confirmed by the time-resolved fluorescence. Binding constants (

Hydrogels are emerging materials in pollutant treatment due to their high absorbability and environmental friendliness. Herein, a novel temperature-sensitive hydrogel based on xanthan gum (XG) and N-isopropylacrylamide (NIPA) was successfully synthesized in a water system using low-cost citric acid as crosslinking agent. The lower critical solution temperature of the honeycomb macroporous XG/NIPA hydrogels was 40 °C. Meanwhile, the hydrogels had good water-absorption capacity and the swelling degree reached up to 70.1. Using XG/NIPA hydrogels to absorb bisphenol A (BPA), the maximum adsorption capacity was as high as 458 mg/g. The process was a multilayer adsorption and the rate-controlling step is chemisorption. Thus, the temperature-sensitive XG/NIPA hydrogel had great potential in absorbing BPA from aqueous solutions.

The interactions between 2-{4-[(3S)-piperidin-3-yl] phenyl}-2H-indazole-7-carboxamide (niraparib) and human serum albumin (HSA) were investigated through fluorescence and computational studies. Fluorescence experiments showed that the static quenching mechanism and the binding constant of the HSA–niraparib system at a single binding site was approximately 4 × 104 L mol−1. Thermodynamic constants indicated that the binding of niraparib to HSA was mainly driven by electrostatic interactions. Competition experiments and molecular docking simulations revealed that niraparib bound to site III of HSA. Synchronous fluorescence and Fourier transform infrared spectroscopy (FT-IR) results suggested that interactions between niraparib and HSA could affect the conformation and microenvironment of HSA. Circular dichroism (CD) measurements revealed that the α-helix contents of HSA negligibly increased after binding with niraparib. Molecular dynamics simulations demonstrated the stability of the binary HSA–niraparib system and confirmed that electrostatic forces accounted for the dominant contribution to system energy between HSA and niraparib.

A novel anion exchange resin, quaternary ammonium– Chlorella vulgaris (QACV), was prepared by introducing quaternary ammonium groups onto dried Chlorella vulgaris as base material. Degrees of epoxy, amine and quaternary ammonium groups of QACV were measured. Water retention, optical microscopy, and Fourier transform infrared spectrometry were used to characterize QAVC. The adsorption behavior of QACV towards Ag(CN) 2 − in different conditions was studied carefully. The results showed that QAVC was efficient to adsorb Ag(CN) 2 − at pH 9–11, and adsorption equilibrium was almost reached in 30 min. Both kinetics and isotherm parameters in the adsorption process were obtained. The data indicated that the pseudo-second-order model provided a good correlation for adsorption of Ag(CN) 2 − on QACV and the calculated rate constant of the adsorption was 3.51 g/(mmol min). The equilibrium data fitted well in the Langmuir isotherm and the estimated maximum adsorption capacity q m was 1.96 mmol/g. The dimensionless separation factor R L was between 0 and 1, suggesting that the adsorption process of Ag(CN) 2 − using QACV was favorable. The QACV could be used successively three times without significantly affecting its adsorption efficiency. Chlorella vulgaris was a potential base material to be modified with quaternary ammonium groups to prepare an adsorbent for adsorption of Ag(CN) 2 − .

Nanostructured manganese oxide materials were prepared from manganese-contained wastewater (MW) using a facile hydrothermal method and adopted as a catalyst to degrade phenol via activation of peroxymonosulphate (PMS). In the WM environment, δ-MnO2 (flower-like Mn-2 with nanosheets) was transformed to α-MnO2 (needle-like Mn-4 with nanowires). Catalytic evaluation experiments demonstrated that the needle-like MnO2 was highly efficient for phenol removal, with a degradation efficiency of 100% within 15 min at the optimal conditions of catalyst dosage 0.2 g/L, PMS dosage 1.5 g/L, initial phenol concentration 0.025 g/L, initial pH 3 and temperature 25°C. Moreover, the needle-like MnO2 catalyst could be recycled and the regenerated material after calcination remained excellent catalytic activity. On the surface of catalysts, PMS was activated by MnIV to generate SO4−∙ which was the major reactive species attacking phenol. Overall, the needle-like MnO2 prepared from MW was an efficient catalyst with low cost for organic wastewater treatment, realizing both Mn resource recycle and organic wastewater treatment.

Nanostructured manganese oxide materials were prepared from manganese-contained wastewater (MW) using a facile hydrothermal method and adopted as catalyst to degrade phenol via activation of peroxymonosulfate (PMS). In the WM environment, δ-MnO2 (flower-like Mn-2 with nanosheets) was transformed to α-MnO2 (needle-like Mn-4 with nanowires). Catalytic evaluation experiments demonstrated that the needle-like MnO2 was highly efficient for phenol removal, with a degradation efficiency of 100% within 15 min at the optimal conditions of catalyst dosage 0.2 g/L, PMS dosage 1.5 g/L, initial phenol concentration 0.025 g/L, initial pH 3 and temperature 25°C. Moreover, the needle-like MnO2 catalyst could be recycled and the regenerated material after calcination remained excellent catalytic activity. On the surface of catalysts, PMS was activated by MnIV to generate SO4¯• which was the major reactive species attacking phenol. Overall, the needle-like MnO2 prepared from MW was an efficient catalyst with low cost for organic wastewater treatment, realizing both Mn resource recycle and organic wastewater treatment.

A large amount of crude glycerol is generated during biodiesel production, but it has little commercial value. In this study, glycerol was used to cultivate Chlorella vulgaris to recycle its surplus, and its effects on microalgal growth and lipid accumulation were investigated. Lipid production in glycerol batch culture was higher than in glucose batch culture. However, the cell growth was slow, and a lag phase was more obvious as glycerol concentration increased from 1 to 30 g L–1. A two-stage fed-batch culture was developed to achieve high cell density and lipid production in C. vulgaris. In this culture, high microalgal cell concentration was first obtained by glucose, and lipid accumulation was enhanced by later additions of crude glycerol. Lipid production and lipid content reached 1663.02 mg L–1 and 36.39%, respectively. Lipids produced by C. vulgaris were good feedstock for biodiesel production.

A novel welan gum-modified cellulose adsorbent was prepared through emulsification, regeneration, and modification. SEM and FTIR were used to characterize the modified cellulose adsorbent. The adsorption isotherms of metal ions on the adsorbent were well fitted by Langmuir model, with the maximum adsorption capacities of 83.6, 77.0, and 67.4 mg/g for Cd2+, Pb2+, and Cu2+, respectively. The adsorption kinetics was well described using the pseudo-first-order model. Moreover, the adsorption capacities for the three metal ions increased with the increase of temperature, and the optimal pH was 5. Furthermore, the thermodynamic analysis indicated that the adsorption processes were spontaneous and endothermic.

Herein, the feasibility to fabricate nitrogen-containing biocarbon material from kitchen waste hydrolysis residue by a molten salt-air -assisted synthetic strategy is investigated. Hierarchical porosity and graphitic carbon nanosheet structure are found for the developed biocarbon. The porosity is mainly induced by O2 and the specific surface area of biocarbon (fabricated in air) reaches 818.65 m2 g−1, much higher than that of O2-free sample (11.84 m2 g−1). Meanwhile, the heteroatom (e.g. N) is also retained and introduced into carbon structure even in air atmosphere. It is also suggested that O2 may accelerate a destructive effect on the order of graphitic structure, while the molten salts of NaCl and KCl play the roles of graphitization catalyst and sealing agent, promoting the graphitization of biocarbon. When the developed biocarbon is applied as electrode material, the as-assembled symmetric supercapacitor exhibits a high energy density of 11.7 Wh kg−1 in 1 M Na2SO4. Forthermore, the applicability of current strategy for industrial biocarbon fabrication is verified by salt recycling test and ten times scale-up trail experiment, which shows great potential for green and large-scale production of advanced carbon materials from biomass precursors, for exmple, kitchen waste hydrolysis residue.

Herein, we report the production of xanthan gum by fermentation using kitchen waste as the sole substrate. The kitchen waste was firstly pretreated by a simple hydrolysis method, after which the obtained kitchen waste hydrolysate was diluted with an optimal ratio 1:2. In a 5-L fermentor, the maximum xanthan production, reducing sugar conversion and utilization rates reached 11.73g/L, 67.07% and 94.82%, respectively. The kinetics of batch fermentation was also investigated. FT-IR and XRD characterizations confirmed the fermentation product as xanthan gum. TGA analyses showed that the thermal stability of the xanthan gum obtained in this study was similar to commercial sample. The molecular weights of xanthan gum were measured to be 0.69-1.37×10(6)g/mol. The maximum pyruvate and acetyl contents in xanthan gum were 6.11% and 2.49%, respectively. This study provides a cost-effective solution for the reusing of kitchen waste and a possible low-cost approach for xanthan production.

A chemo-biochemical process for desulfurization of simulated natural gas containing hydrogen sulfide (H2S) was investigated. The results showed that using polyurethane foam as a support for immobilization of Acidithiobacillus ferrooxidans obtained good biological oxidation performance and the maximum oxidation rate of ferrous iron was 4.12 kg m−3 h−1. Moreover, a semi-empirical formula was set up for calculating theoretical ferrous oxidation rate as a function of influent Fe2+ and Fe2+ concentration in the bioreactor. The integrated chemical and biological process achieved removal efficiencies of about 80% when treating high concentrations of H2S (15 000 ± 100 ppmv). © 2012 Society of Chemical Industry

Massive ferrous sulfate with excess sulfuric acid is produced in titanium dioxide industry each year, ending up stockpiled or in landfills as solid waste, which is hazardous to environment and in urgent demand to be recycled. In this study, waste ferrous sulfate was used as a second raw material to synthesize nano α-Fe2O3 red pigment powders with a bacteria-assisted oxidation process by Acidithiobacillus ferrooxidans. The synthesis route, mainly consisting of bio-oxidation, precipitation and calcination, was investigated by means of titration, thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray fluorescence (XRF) to obtain optimum conditions. Under the optimum conditions, nano α-Fe2O3 red pigment powders contained 98.24wt.% of Fe2O3 were successfully prepared, with a morphology of spheroidal and particle size ranged from 22nm to 86nm and averaged at 45nm. Moreover, the resulting product fulfilled ISO 1248-2006, the standards of iron oxide pigments.

A novel anion exchange resin based on cellulose has been prepared to adsorb for the urgent demand of silver and the high toxicity of metal-cyanide complexes. Quaternary ammonium groups were grafted onto cellulose beads as main active sites in tentacle-type through a series of chemical reactions. The substitution degree of each reaction was determined to be about 0.854, 2.125, and 2.899 mmol g−1, respectively. The resin exhibited excellent spherical shape with microporous structure by the observation of optical microscopy and scanning electron microscope. Moreover, the adsorption experiments demonstrated the adsorption was fast in alkaline condition. Fitting the data into isotherm and kinetic models gave the conclusion that the adsorption behavior matched better with Langmuir model and pseudo-second-order kinetic in initial time followed pseudo-first-order kinetic model in later phase. The equilibrium adsorption capacity was determined to be 3.016 mmol g−1. With the advantages of high capacity, short equilibrium time, and alkaline resistance, the resin would be considered to a top-priority adsorbent for the separation of . © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40987.

Microalgal biofuel production from wastewater has economic and environmental advantages. This article investigates the lipid production from high chemical oxygen demand (COD) bioethanol wastewater without dilution or additional nutrients, using a newly isolated heterotrophic microalga, Chlorella vulgaris LAM-Q. To enhance lipid accumulation, the combined effects of important operational parameters were studied via response surface methodology. The optimal conditions were found to be temperature of 22.8℃, initial pH of 6.7, and inoculum density of 1.2 × 10(8) cells/ml. Under these conditions, the lipid productivity reached 195.96 mg/l/d, which was markedly higher than previously reported values in similar systems. According to the fatty acid composition, the obtained lipids were suitable feedstock for biodiesel production. Meanwhile, 61.40% of COD, 51.24% of total nitrogen, and 58.76% of total phosphorus were removed from the bioethanol wastewater during microalgal growth. In addition, 19.17% of the energy contained in the wastewater was transferred to the microalgal biomass in the fermentation process. These findings suggest that C. vulgaris LAMQ can efficiently produce lipids from high-concentration bioethanol wastewater, and simultaneously performs wastewater treatment.

The oleaginous microalga Chlorella sp. LAM-H screened from freshwater was proven to be a prospective feedstock for oil production according to its fatty acid composition. In order to enhance lipid production, response surface methodology (RSM) was used with central composite design (CCD) to optimize the heterotrophic cultivation of microalgae. The experiment results showed that a satisfactory second-order polynomial regression equation was achieved with a high coefficient of determination ( R 2 = 0.9911) in analysis of variance. The effects of individual factors and their interactions on lipid productivity were successfully revealed. The greatest lipid productivity reached 247.16 mg l −1 d −1 under the optimal conditions of glucose concentration 26.2 g l −1 , sodium nitrate concentration 2.06 g l −1 and temperature 28.18 °C. Moreover, validation tests were performed and the results were very close to the predicted values. It was demonstrated that the obtained model was effective for predicting lipid productivity of the isolated microalga.