RhoA/ROCK1 regulates the mitochondrial dysfunction through Drp1 induced by Porphyromonas gingivalis in endothelial cells.

Porphyromonas gingivalis (P. gingivalis) is a pivotal pathogen of periodontitis. Our previous studies have confirmed that mitochondrial dysfunction in the endothelial cells caused by P. gingivalis was dependent on Drp1, which may be the mechanism of P. gingivalis causing endothelial dysfunction. Nevertheless, the signalling pathway induced the mitochondrial dysfunction remains unclear. The purpose of this study was to investigate the role of the RhoA/ROCK1 pathway in regulating mitochondrial dysfunction caused by P. gingivalis. P. gingivalis was used to infect EA.hy926 cells (endothelial cells). The expression and activation of RhoA and ROCK1 were assessed by western blotting and pull-down assay. The morphology of mitochondria was observed by mitochondrial staining and transmission electron microscopy. Mitochondrial function was measured by ATP content, mitochondrial DNA and mitochondrial permeability transition pore openness. The phosphorylation and translocation of Drp1 were evaluated using western blotting and immunofluorescence. The role of the RhoA/ROCK1 pathway in mitochondrial dysfunction was investigated using RhoA and ROCK1 inhibitors. The activation of RhoA/ROCK1 pathway and mitochondrial dysfunction were observed in P. gingivalis-infected endothelial cells. Furthermore, RhoA or ROCK1 inhibitors partly prevented mitochondrial dysfunction caused by P. gingivalis. The increased phosphorylation and mitochondrial translocation of Drp1 induced by P. gingivalis were both blocked by RhoA and ROCK1 inhibitors. In conclusion, we demonstrate that the RhoA/ROCK1 pathway was involved in mitochondrial dysfunction caused by P. gingivalis by regulating the phosphorylation and mitochondrial translocation of Drp1. Our research illuminated a possible new mechanism by which P. gingivalis promotes endothelial dysfunction.

Enhanced antidepressant effects of BDNF-quercetin alginate nanogels for depression therapy.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) with neuronic development and function is a promising therapeutic agent for treating depressive disorder, according to the neurotrophin hypothesis. However, the delivery of BDNF into the brain is not easy as these large protein molecules cannot efficiently cross the blood-brain barrier (BBB) and easily suffer oxidative damage in vivo. Therefore, the quercetin-based alginate nanogels (quercetin nanogels) loaded with BDNF have been developed, which could efficiently bypass the BBB via the nose-to-brain pathway and protect BDNF from oxidative damage, providing an effective route for the therapy of depressive disorders by intranasal delivery. RESULTS: Quercetin nanogels exhibited uniform size distribution, excellent biocompatibility, and potent antioxidant and anti-inflammatory activities. Quercetin nanogels in the thermosensitive gel achieved sustained and controlled release of BDNF with non-Fick's diffusion, exhibited rapid brain distribution, and achieved nearly 50-fold enhanced bioavailability compared to oral quercetin. Quercetin nanogels as a therapeutic drug delivery carrier exerted antidepressant effects on reserpine-induced rats, effectively delivered BDNF to reverse despair behavior in stress-induced mice, and exhibited antidepressant effects on chronic mild unpredictable stimulation (CUMS) rats. These antidepressant effects of BDNF-Quercetin nanogels for CUMS rats are associated with the regulation of the glutamatergic system, PI3K-Akt, and BDNF-TrkB signaling pathway. CONCLUSIONS: In this study, we provide a promising strategy for brain delivery of BDNF for treating depressive disorders, effectively achieved through combining quercetin nanogels and intranasal administration.

The mechanism of enhanced lignin regulating foliar Cd absorption and yield in rice (Oryza sativa L.).

The impact of atmospheric deposition of cadmium (Cd) in cereal crops has become a global concern. Enhanced lignin content was expected to benefit the plant performance against Cd exposure. To date, however, the underlying mechanisms of lignin regulating foliar Cd absorption in rice (Oryza sativa L.) and its effect on grain yield remains unclear. In present study, the effect and mechanism of rice in response to leaf Cd exposure were investigated using 113Cd stable isotope and a lignin-increased rice mutant. The highest Cd uptake efficiency and uptake amount was observed in wild type (WT) plant grown in the maturity period, which were 3-fold higher than in mutant plant. Compared to WT, the mutant exhibited 14.75% and 25.43% higher contents in G- and S-unit of lignin monomers. Lignin biosynthesis and polymerization related genes (OsPAL/OsCOMT/Os4CL3/OsLAC5/OsLAC15) were significantly up-regulated in mutants. In addition, the enzyme activities involved in the above process were also significantly increased by 1.24-1.49-fold. The increased Cd retention in cell wall and decreased gene expression levels of OsNRAMP5, OsHMA3 and OsIRT1 in mutant indicated that lignin effectively inhibited Cd transportion in plant tissues. Moreover, the antioxidant capacity and photosynthesis efficiency in mutant plant were obviously improved, leading to higher Cd tolerance and increased grain yield. Our results revealed the molecular and physiological mechanisms of enhanced lignin regulating foliar Cd absorption and yield in rice, and provided the valuable rice genotype to ensure food safety.

Periodontal disease and Helicobacter pylori infection in oral cavity: a meta-analysis of 2727 participants mainly based on Asian studies.

OBJECTIVES: To assess the association between periodontal disease and Helicobacter pylori (H. pylori) infection in oral cavity. MATERIALS AND METHODS: We searched PubMed, Embase, Web of Science, Cochrane library, Gray literature, and clinicaltrials.gov for eligible studies up to September 25, 2019. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. The random-effects model was used with the software STATA 13.0. The Newcastle-Ottawa-Scale was used for quality evaluation. RESULTS: Twelve observational studies (eight from Asia, one from Europe, and three from the South America) involving 2727 participants were included in the meta-analysis. The overall pooled results showed that H. pylori infection in oral cavity was associated with periodontal disease (OR 2.53, 95% CI 1.86-3.44, P < 0.05). No significant heterogeneity among the articles was observed (I2 = 44.3%, P < 0.05). The sensitivity analysis indicated that the result of our meta-analysis was generally stable. The Begg test and the Egger test both showed no publication bias was observed (P = 0.45 and P = 0.18 respectively). CONCLUSIONS: Based on current available evidence, it seemed there was a correlation between oral H. pylori infection and the occurrence of periodontal disease. However, since most of the data comes from Asia, more large-scale investigations with high quality from all over the world are needed to confirm the association. CLINICAL RELEVANCE: H. pylori infection in oral may have a positive association with the prevalence of periodontal disease mainly in Asian populations.

Characterization and Dimethyl Phthalate Flocculation Performance of the Cationic Polyacrylamide Flocculant P(AM-DMDAAC) Produced by Microwave-Assisted Synthesis.

A composite flocculant P(AM-DMDAAC) was synthesized by the copolymerization of acrylamide (AM) and dimethyl diallyl ammonium chloride (DMDAAC). By using microwave (MV) assistance with ammonium persulfate as initiator, the synthesis had a short reaction time and yielded a product with good solubility. Fourier-transform infrared spectroscopy, scanning electron microscopy, and differential thermal analysis-thermogravimetric analysis were employed to determine the structure and morphology of P(AM-DMDAAC). The parameters affecting the intrinsic viscosity of P(AM-DMDAAC), such as MV time, mass ratio of DMDAAC to AM, bath time, reaction temperature, pH value, and the dosages of ammonium persulfate initiator, EDTA, sodium benzoate, and urea were examined. Results showed that the optimum synthesis conditions were MV time of 1.5 min, m(DMDAAC):m(AM) of 4:16, 0.5 wt‱ initiator, 0.4 wt‱ EDTA, 0.3 wt‱ sodium benzoate, 2 wt‱ urea, 4 h bath time, reaction temperature of 40 °C, and pH of 2. The optimal dimethyl phthalate (DMP) removal rate can reach 96.9% by using P(AM-DMDAAC), and the P(AM-DMDAAC) had better flocculation than PAM, PAC, and PFS.

Integrated morphological, physiological and transcriptomic analyses reveal response mechanisms of rice under different cadmium exposure routes.

Rice (Oryza sativa) is one of the major cereal crops and takes up cadmium (Cd) more readily than other crops. Understanding the mechanism of Cd uptake and defense in rice can help us avoid Cd in the food chain. However, studies comparing Cd uptake, toxicity, and detoxification mechanisms of leaf and root Cd exposure at the morphological, physiological, and transcriptional levels are still lacking. Therefore, experiments were conducted in this study and found that root Cd exposure resulted in more severe oxidative and photosynthetic damage, lower plant biomass, higher Cd accumulation, and transcriptional changes in rice than leaf Cd exposure. The activation of phenylpropanoids biosynthesis in both root and leaf tissues under different Cd exposure routes suggests that increased lignin is the response mechanism of rice under Cd stress. Moreover, the roots of rice are more sensitive to Cd stress and their adaptation responses are more pronounced than those of leaves. Quantitative PCR revealed that OsPOX, OsCAD, OsPAL and OsCCR play important roles in the response to Cd stress, which further emphasize the importance of lignin. Therefore, this study provides theoretical evidence for future chemical and genetic regulation of lignin biosynthesis in crop plants to reduce Cd accumulation.

Multiple insights into lignin-mediated cadmium detoxification in rice (Oryza sativa).

Cadmium (Cd) is readily absorbed by rice and enters the food chain, posing a health risk to humans. A better understanding of the mechanisms of Cd-induced responses in rice will help in developing solutions to reduce Cd uptake in rice. Therefore, this research attempted to reveal the detoxification mechanisms of rice in response to Cd through physiological, transcriptomic and molecular approaches. The results showed that Cd stress restricted rice growth, led to Cd accumulation and H2O2 production, and resulted cell death. Transcriptomic sequencing revealed glutathione and phenylpropanoid were the major metabolic pathways under Cd stress. Physiological studies showed that antioxidant enzyme activities, glutathione and lignin contents were significantly increased under Cd stress. In response to Cd stress, q-PCR results showed that genes related to lignin and glutathione biosynthesis were upregulated, whereas metal transporter genes were downregulated. Further pot experiment with rice cultivars with increased and decreased lignin content confirmed the causal relationship between increased lignin and reduced Cd in rice. This study provides a comprehensive understanding of lignin-mediated detoxification mechanism in rice under Cd stress and explains the function of lignin in production of low-Cd rice to ensure human health and food safety.

Long-term Pegylated GH for Children With GH Deficiency: A Large, Prospective, Real-world Study.

CONTEXT: The evidence of long-term polyethylene glycol recombinant human GH (PEG-rhGH) in pediatric GH deficiency (GHD) is limited. OBJECTIVE: This study aimed to examine the effectiveness and safety of long-term PEG-rhGH in children with GHD in the real world, as well as to examine the effects of dose on patient outcomes. DESIGN: A prospective, observational, posttrial study (NCT03290235). SETTING, PARTICIPANTS AND INTERVENTION: Children with GHD were enrolled from 81 centers in China in 4 individual clinical trials and received weekly 0.2 mg/kg/wk (high-dose) or 0.1 to <0.2 mg/kg/wk (low-dose) PEG-rhGH for 30 months. MAIN OUTCOMES MEASURES: Height SD score (Ht SDS) at 12, 24, and 36 months. RESULTS: A total of 1170 children were enrolled in this posttrial study, with 642 patients in the high-dose subgroup and 528 in the low-dose subgroup. The Ht SDS improved significantly after treatment in the total population (P < 0.0001), with a mean change of 0.53 ± 0.30, 0.89 ± 0.48, 1.35 ± 0.63, 1.63 ± 0.75 at 6 months, 12 months, 24 months, and 36 months, respectively. In addition, the changes in Ht SDS from baseline were significantly improved in the high-dose subgroup compared with the low-dose subgroup at 6, 12, 24, and 36 months after treatment (all P < 0.05). A total of 12 (1.03%) patients developed serious adverse events. There was no serious adverse event related to the treatment, and no AEs leading to treatment discontinuation or death occurred. CONCLUSIONS: PEG-rhGH showed long-term effectiveness and safety in treating children with GHD. Both dose subgroups showed promising outcomes, whereas PEG-rhGH 0.2 mg/kg/wk might show additional benefit.

Glycosaminoglycan-based injectable hydrogels with multi-functions in the alleviation of osteoarthritis.

Osteoarthritis (OA), as an "undead cancer", causes a serious burden for both individuals and society. In this study, a glycosaminoglycan-based injectable hydrogel was prepared with hyaluronic acid (HA), chondroitin sulfate E disaccharide (ΔUA-diSE) and thermosensitive Pluronic F127 (PF127) to provide a new strategy for OA alleviation. Both in vitro and in vivo biological evaluations were introduced to investigate the slow-release capacity, related mechanisms, and effectiveness of PF-HA-diSE on OA. The results demonstrated that PF-HA-diSE could alleviate OA effectively by regulating the complement system, especially the formation of C5b-9, and its downstream signals. Interestingly, we also found that PF127 was not only a drug carrier, but may have the potential on inhibiting C5b-9 formation. Altogether, these findings provided a more effective local drug delivery system for glycosaminoglycans in better treatment of OA and related diseases.

[Rheological properties of poloxamer 407 aqueous solutions].

Rheological properties of poloxamer 407 (brand named Pluronic F127) were examined by changing shear rate, temperature and the recovery properties of apparent viscosity after heating for several times. The results indicated that poloxamer 407 aqueous solution showed a Newtonian behavior at a low concentration while it might be a pseudoplastic fluid when the concentration reached a certain point. The thixotropy and the sol-gel transition temperature decreased with increasing the concentration (it could be an in situ gel at body temperature when the concentration of poloxamer 407 up to 15.25%). The results that obtained from the theological data would be useful in the application of poloxamer 407 such as in situ gel preparation.

Porphyromonas gingivalis infection promotes mitochondrial dysfunction through Drp1-dependent mitochondrial fission in endothelial cells.

Porphyromonas gingivalis (P. gingivalis), a key pathogen in periodontitis, has been shown to accelerate the progression of atherosclerosis (AS). However, the definite mechanisms remain elusive. Emerging evidence supports an association between mitochondrial dysfunction and AS. In our study, the impact of P. gingivalis on mitochondrial dysfunction and the potential mechanism were investigated. The mitochondrial morphology of EA.hy926 cells infected with P. gingivalis was assessed by transmission electron microscopy, mitochondrial staining, and quantitative analysis of the mitochondrial network. Fluorescence staining and flow cytometry analysis were performed to determine mitochondrial reactive oxygen species (mtROS) and mitochondrial membrane potential (MMP) levels. Cellular ATP production was examined by a luminescence assay kit. The expression of key fusion and fission proteins was evaluated by western blot and immunofluorescence. Mdivi-1, a specific Drp1 inhibitor, was used to elucidate the role of Drp1 in mitochondrial dysfunction. Our findings showed that P. gingivalis infection induced mitochondrial fragmentation, increased the mtROS levels, and decreased the MMP and ATP concentration in vascular endothelial cells. We observed upregulation of Drp1 (Ser616) phosphorylation and translocation of Drp1 to mitochondria. Mdivi-1 blocked the mitochondrial fragmentation and dysfunction induced by P. gingivalis. Collectively, these results revealed that P. gingivalis infection promoted mitochondrial fragmentation and dysfunction, which was dependent on Drp1. Mitochondrial dysfunction may represent the mechanism by which P. gingivalis exacerbates atherosclerotic lesions.

Effects of different plastic film mulching on soil hydrothermal conditions and grain-filling process in an arid irrigation district.

Plastic film mulching has been extensively used for spring maize (Zea mays L.) production in the Hetao Irrigation District (HID). Determining whether transparent plastic film mulching results in premature senescence and yield reduction of spring maize still needs to be verified. A two-year field experiment was conducted in the HID that involved planting spring maize under three mulching practices on a flat plot 1) without mulching (control treatment, CK), 2) with black plastic film mulching (BM), 3) with transparent plastic film mulching (TM). The results indicated that TM and BM were superior to CK in terms of effects on soil hydrothermal conditions. Compared with BM, TM produced significantly higher soil temperature at V6, and had no significant temperature effect at V12, R1, R3, and R6. Both TM and BM promoted early seedling emergence and earlier silking, and TM extended the duration of the reproductive stages by 1-2 days compared with BM, and 4-5 days longer than CK. TM and BM produced greater kernel weights and kernel volumes in the superior and middle portions of the ear than CK. TM produced significantly greater total kernel weights per ear than BM at and after 23 days after silking. TM significantly increased grain-filling rate and length of the active grain-filling period compared with BM and CK. Additionally, TM and BM produced significantly higher photosynthetic parameters than CK at the grain-filling stage in the two study years. The net photosynthesis rate for TM was significantly greater than for BM. TM and BM significantly increased grain yields by 28.1% and 15.1%, respectively, in 2019 over CK, and by 24.6% and 21.1% in 2020. Transparent plastic film mulching could serve as a promising adaptive management practice to increase resource use efficiency and to improve maize productivity in the HID.

[Multivesicular liposome sustained delivery of a novel synthetic electropositive Positive GnRH antagonist LXT-101: preparation and in vitro evaluation].

Using a simple method to determine the interaction between peptide and lipid bilayer and then deciding how to modify formulation from classic DepoFoam technology, multivesicular liposome of LXT-101 (DepoLXT-101) was prepared and characterized by in vitro evaluation. The electrostatic adsorption between peptide and lipid bilayer was observed by zeta potential and fluorescence spectrum. Anionic surfactants were added to stable the multiple emulsion and minimize the opposite effects resulted from drug. Encapsulation efficiency was determined by RP-HPLC. Morphology, particle size of DepoLXT-101 particles were characterized and their in vitro release was studied in sodium chloride solution. The DepoLXT-101 particles were prepared with good encapsulation efficiency, narrow size distribution and multivesicular construction. Over 95% of the DepoLXT-101 particles were in a size range of 5-20 microm. The in vitro assay in sodium chloride solution at 37 degrees C showed that 70%-90% of the peptide was released from particles slowly over 11 days. Multivesicular liposome sustained delivery of synthetic cationic peptides could be successfully prepared by the method.

Formulation optimization of self-emulsifying preparations of puerarin through self-emulsifying performances evaluation in vitro and pharmacokinetic studies in vivo.

The main purpose of this work is to prepare self-emulsifying drug delivery system (SEDDS) of a poorly water soluble drug, puerarin. Solubility of puerarin was determined in various oils and surfactants. Oleic acid and Tween 80 provided higher solubility. Addition of propylene glycol as cosurfactant improved solubility of puerarin and the spontaneity of self-emulsification. A series of mixtures comprising oleic acid, propylene glycol and Tween 80 were prepared and their self-emulsifying properties were studied. Pseudo-ternary phase diagrams were constructed to identify the efficient self-emulsification region and particle sizes of the resultant emulsions were determined using a laser diffraction sizer. The pharmacokinetic behaviors of three different SEDDS formulations (F2, F3, F4) were investigated in Beagle dogs. The bioavailability was compared using the pharmacokinetic parameters, peak plasma concentration (C(max)), time to reach peak plasma concentration (T(max)) and total area under the plasma concentration-time curve (AUC(0-t)). AUC(0-t) was significantly higher in formulation F2 group (5.201 +/- 0.511) ng x mL(-1) x h and formulation F3 group (5.174 +/- 0.498) ng x mL (-1) x h than that in formulation F4 group (3.013 +/- 0.623) ng x mL(-1) x h. Also, C(max) was significantly higher in formulation F2 group (1.524 +/- 0.125) ng x mL(-1) and formulation F3 group (1.513 +/- 0.157) ng x mL(-1) than that in formulation F4 group (0.939 +/- 0.089) ng x mL(-1). Further analysis of the data showed a statistically significant difference between F2 and F4 (P < 0.01) as well as F3 and F4 (P < 0.01) with regard to the values of AUC(0-infinity) and C(max) for three SEDDS formulations, but not between those of F2 and F3 (P > 0.05). From these studies, the SEDDS formulation containing oleic acid (17.5%), Tween 80 (34.5%) and propylene glycol (34.5%) (w/w) was selected as an optimized SEDDS formulation of puerarin. The data suggest the potential use of SEDDS to improve oral absorption of puerarin.

Changing profiles of bound water content and distribution in the activated sludge treatment by NaCl addition and pH modification.

Currently the dewatering of activated sludge from wastewater treatment plants is a problem not well solved. Extracellular polymeric substances (EPS), including loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS), are highly hydrated biopolymers and play important roles in sludge dewatering. In the present work, two types of treatments, i.e., salt addition and pH modification, were proposed to evaluate the effects of bound water content and its distribution on the dewatering performance of activated sludge. Results show that the bound water content in activated sludge was deeply related to the floc structures and EPS compositions. Both salt addition and acid treatment altered the flocculated matrix and increased the contents of LB-EPS, resulting in the release of trapped water and reduction in sludge volume. In addition, the chemical treatments also affected the distribution of bound water. The internal water content increased upon the dose of NaCl, leading to a decreased water content trapped in EPS. Hence, salt addition caused a slower filtration rate, but did not effectively decrease the total water content, although the EPS were decomposed. Under acidic conditions, cell lysis helped to release the intracellular water and further enhance the sludge dewatering performance. In contrast, conditioning with low-dosage alkali increased the bound water content and deteriorated the sludge dewaterability. Therefore, an in-depth investigation into the mechanisms is useful to optimize the activated sludge dewatering process.

Enhanced dewatering of excess activated sludge through decomposing its extracellular polymeric substances by a Fe@Fe2O3-based composite conditioner.

Efficient sludge dewatering methods are highly desired by municipal wastewater treatment plants. In this study, Fe@Fe2O3 nanomaterial, combined with polydiallyldimethylammonium chloride (PDMDAAC) and H2SO4, was used for sludge dewatering. This composite conditioner exhibited an excellent dewatering capability. By using uniform design, the optimized dosages of Fe@Fe2O3, H2SO4 and PDMDAAC were determined to be 40, 136 and 4.8mg/gDS (dry solids), respectively. The moisture content of sludge cake decreased from 78.1% to 64.8%, and the capillary suction time from 56 to 21s. The sludge extracellular polymeric substances (EPS) were decomposed, resulting in greater conversion of the bound water into free water and the release of free water. The electron spin resonance results show that the molecular oxygen activation process induced by Fe@Fe2O3 produced hydroxyl radicals, which were mainly responsible for the EPS decomposition. In this way, an efficient composite conditioner for enhancing sludge dewatering was developed.

[Assesement of tretinoin with a self-emulsifying formulation in vitro and in vivo].

AIM: To evaluate the self-emulsifying ability and dissolution behavior of tretinoin in vitro and the pharmacokinetic behavior in beagle dogs. METHODS: The self-emulsifying rate was evaluated by determining the intensity of scattered light at different time and the particle size of resultant emulsions after self-emulsifying were observed by optical microscope. The plasma concentrations were determined by HPLC and dissolution and pharmacokinetic behavior of self-emulsifying formulations were evaluated by comparison with commercial capsules. RESULTS: The area under the curve (AUC) was significantly higher in the tretinoin self-emulsifying formulation group (3048.0 mg x h x L(-1)) than that in the commercial capsule group (1826.0 mg x h x L(-1)). Also, Tmax was smaller in the self-emulsifying formulation group (1.25 h) compared with market products (2 h) and the dissolved amount from self-emulsifying formulations in water at 15 min was much higher (more than 80%) than that of the market products (less than 5%). CONCLUSION: The self-emulsifying drug delivery systems can increase drug dissolution in vitro and absorption in vivo significantly.

Probing the roles of Ca(2+) and Mg(2+) in humic acids-induced ultrafiltration membrane fouling using an integrated approach.

Membrane fouling induced by natural organic matter (NOM) negatively affects the performance of ultrafiltration (UF) technology in producing drinking water. Divalent cation is found to be an important factor that affects the NOM-induced membrane fouling process. In this work, attenuated total reflection-Fourier transformation infrared spectroscopy (ATR-FTIR) coupled with quartz crystal microbalance (QCM), assisted by isothermal titration calorimetry (ITC), is used to explore the contribution of Mg(2+) and Ca(2+), the two abundant divalent cations in natural water, to the UF membrane fouling caused by humic acid (HA) at a molecular level. The results show that Ca(2+) exhibited superior performance in accelerating fouling compared to Mg(2+). The hydrophobic polyethersulfone (PES) membrane exhibited greater complexation with HA in the presence of Mg(2+) and Ca(2+), compared to the hydrophilic cellulose membrane, as evidenced by the more intense polysaccharide C-O, aromatic C=C and carboxylic C=O bands in the FTIR spectra. The QCM and ITC measurements provide quantitative evidence to support that Ca(2+) was more effective than Mg(2+) in binding with HA and accumulating foulants on the membrane surfaces. The higher charge neutralization capacity and more favorable binding ability of Ca(2+) were found to be responsible for its greater contribution to the NOM-induced membrane fouling than Mg(2+). This work offers a new insight into the mechanism of cation-mediated NOM-induced membrane fouling process, and demonstrates that such an integrated ATR-FTIR/QCM/ITC approach could be a useful tool to explore other complicated interaction processes in natural and engineered environments.

Enzymatic saccharification of sugarcane bagasse by N-methylmorpholine-N-oxide-tolerant cellulase from a newly isolated Galactomyces sp. CCZU11-1.

Based on the enrichment culture strategy, a novel N-methylmorpholine-N-oxide (NMMO)-tolerant cellulase-producing strain Galactomyces sp. CCZU11-1 was isolated from soil samples. After the optimization of culture condition, the highest FPA (13.4 U/mL) and CMCase (24.5 U/mL) were obtained. In both culture and reaction media containing NMMO 25% (w/v), the cellulase from Galactomyces sp. CCZU11-1 still had good activity. Furthermore, high saccharification rate was obtained in aqueous-NMMO media. Moreover, the fermentability of the hydrolyzates, obtained after enzymatic in situ saccharification of the NMMO-pretreated sugarcane bagasse, was evaluated using Saccharomyce scerevisiae. In conclusion, Galactomyces sp. CCZU11-1 is a promising candidate as high NMMO-tolerant cellulase producer and has potential application in future.