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• Red macroalgae, Gloiopeltis furcata, was used as biomass. • The highest Ep 79.5% value was obtained in thermal acid hydrolysis with HNO 3. • Neither the wild type nor Gal3 overexpression strain could utilize all of the galactose in hydrolysate. • Saccharomyces cerevisiae deleted Gal80 gene could enhance the gene expression related to galactose consumption. Glucose and galactose are monosaccharides obtained from Gloiopeltis furcata (Red algae). A total monosaccharide yield of 62.3 g/L was obtained from G. furcata using thermal acid hydrolysis and enzymatic saccharification. Activated carbon was used to eliminate hydroxymethylfurfural (HMF) from the hydrolysate. Previously obtained monosaccharides are used for ethanol production by Saccharomyces cerevisiae. S. cerevisiae consumes glucose first, then galactose. The methods for reducing fermentation time and increasing the ethanol yield coefficient using the simultaneous consumption of glucose and galactose have been evaluated. Gal3p and Gal80p of S. cerevisiae act as signal transducers that govern the galactose inducer Gal4p mediated transcriptional activation of the Gal gene family. Gal80p binds to Gal4p for transcription deactivation. Therefore, Gal80p was deleted for Gal4p expression without interruption. [ABSTRACT FROM AUTHOR]

Background: Adult-onset Still's disease (AOSD) is an adult form of systemic juvenile idiopathic arthritis (JIA) that differs from the latter in its classification. This study evaluated the concordance between the International League Against Rheumatism (ILAR) criteria for systemic JIA and the Yamaguchi criteria and then compared their possible prognostic value in patients with AOSD. Methods: In a retrospective review of 169 adults with suspected AOSD, patients were classified according to the Yamaguchi or ILAR criteria. Then the concordance in cross-referencing the other group with the different criteria was investigated and the sensitivity and specificity of each set of criteria were determined. Disease activity markers in AOSD patients were correlated with positivity according to both systems. Results: Concordance was good in patients with suspected AOSD (k = 0.7144, p < 0.001) and low in those with a diagnosis of AOSD (k = 0.3787, p < 0.001). The sensitivity of the ILAR criteria in AOSD patients was 0.8864 (95% confidence interval (CI): 0.8322-0.9405), and the specificity was 0.7838 (0.6511, 0.9164). Positivity according to the ILAR criteria correlated with the systemic score (r = 0.763, p < 0.0001) and C-reactive protein levels (r = 0.183, p = 0.0356) and was associated with a relapse (odds ratio: 1.589, 95% CI: 1.043-2.421), macrophage activation syndrome (MAS; odds ratio: 1.993, 95% CI: 1.218-3.263) and care in the intensive care unit (ICU; odds ratio: 2.087, 95% CI: 1.086-4.011). Conclusions: In AOSD patients, there is fair concordance between the Yamaguchi and ILAR criteria for systemic JIA. Positive ILAR criteria may be useful for identifying AOSD patients at high risk for relapse, MAS and the need for ICU care. Further studies including larger populations from several centers are needed to confirm our results regarding the utility of the ILAR criteria in AOSD patients. [ABSTRACT FROM AUTHOR]

Background and purpose Although progression of small deep subcortical infarct (PSDI) comprises 12% to 36% of all small deep subcortical infarcts, the therapy for progression is not clear. This study investigated whether induced-hypertension therapy using phenylephrine is a useful therapy for PSDI. Methods A group of 2427 consecutive patients, diagnosed with stroke at a tertiary hospital over a period of 4 years was reviewed retrospectively. We analyzed patients with small deep subcortical infarct using clinical, laboratory, and pulse wave velocity (PWV). PSDI is defined as one or more increase in the motor score according to the NIHSS. Good outcome was designated as a modified Rankin scale of 0 to 2 at discharge. Results Among all 662 patients who had a small deep subcortical infarct, 66 patients experienced motor progression (9.97%). The induced-hypertension therapy group (n = 25) received phenylephrine, and the conventional group (n = 41) received anticoagulation therapy such as heparin, volume expansion, or both. Although there were no significant differences in baseline clinical and laboratory findings, the PSDI group showed a significantly more frequent decrease in blood pressure at progression ( P < 0.0001) and higher PWV ( P = 0.001). The phenylephrine group ( vs the conventional group) had a lower NIHSS score ( P = 0.036) and good outcome at discharge ( P = 0.004). In multiple regression analysis, PWV (OR, 1.004 per 1-cm/s increase; 95% CI, 1.001–1.008; P = 0.018) was an independent predictor of good outcome in the phenylephrine group. A side effect of phenylephrine treatment was dysuria (n = 1). Conclusions The present study suggests that vascular stiffness can be not only a predictor for PSDI but also a predictor of motor improvement after induced-hypertension therapy using phenylephrine in lacunar stroke. [ABSTRACT FROM AUTHOR]

Bokbunja (Rubus coreanusMiquel) and six other berries were analyzed for physico-chemical properties and antioxidant activities, using four different methods (DPPH•, ABTS•+, FRAP, and reducing power). The total polyphenol, total flavonoid, and total anthocyanin contents of bokbunja were significantly higher than those of other berries, followed by mulberry, blackberry, cranberry, raspberry, wild strawberry, and strawberry. Antioxidant activity assays also showed that bokbunja’s antioxidant activity exceeded that of the other berries. Bokbunja had not only significantly higher levels of kaempferol, quercetin, and ellagic acid but also the highest ellagic acid content (408.57 mg kg−1fresh weight). The potential antioxidant activities of bokbunja might be ascribed to its high total polyphenol, total flavonoid, and total anthocyanin contents. Ellagic acid may also affect antioxidant activity, although the concentrations of other phenolic compounds such as kaempferol, quercetin, and quercetin-3-O-rutinoside were high in other berries such as blackberry, cranberry, and mulberry. [ABSTRACT FROM PUBLISHER]

Carbazole compounds modified with a pyridoindole moiety were examined as thermally stable high triplet energy host materials for tris[1-(2,4-diisopropyldibenzo[b,d]furan-3-yl)-2-phenylimidazole] (Ir(dbi) 3 ) based blue phosphorescent organic light-emitting diodes. A well-known carbazole compound, N,N′-dicarbazolyl-3,5-benzene, was substituted with one or two pyridoindole moieties to develop the thermally stable host materials for Ir(dbi) 3 blue triplet emitters. Remarkably high glass transition temperature of 196 °C and thermal decomposition temperature of 486 °C in addition to high triplet energy of 2.89 eV were achieved by the pyridoindole modification. The pyridoindole modified carbazole compounds also delivered high quantum efficiency of 25.4% in the blue phosphorescent devices by doping Ir(dbi) 3 . [ABSTRACT FROM AUTHOR]

Saccharomyces cerevisiae strains tolerant to salt stress are important for the production of single-cell protein using kimchi waste brine. In this study, two strains (TN-1 and TN-2) tolerant of up to 10 % (w/v) NaCl were isolated by screening a transposon-mediated mutant library. The determination of transposon insertion sites and Northern blot analysis identified two genes, MDJ1 and VPS74, and revealed disruptions of the open reading frame of both genes, indicating that salt tolerance can be conferred. Such tolerant phenotypes reverted to sensitive phenotypes on the autologous or overexpression of each gene. The two transposon mutants grew faster than the control strain when cultured at 30 °C in rich medium containing 5, 7.5 or 10 % NaCl. The genes identified in this study may provide a basis for application in developing industrial yeast strains. [ABSTRACT FROM AUTHOR]

Abstract: Removal characteristics of polycyclic aromatic hydrocarbons (PAHs) from low-permeable soil using a surfactant-enhanced electrokinetic (EK) process were investigated. Phenanthrene and kaolinite were selected as a representative PAH and a model soil. A nonionic surfactant, alkyl polyglucosides (APG), and an anionic surfactant, Calfax 16L-35, were used to enhance the solubility of phenanthrene. The two surfactants showed similar solubilization capacities for phenanthrene, while only APG was affected by sorption. When surfactants were applied to EK process, the electrical potential gradient was lower than that of water. The electroosmotic flow (EOF) decreased as the concentration of surfactant increased. In the case of APG, the removal efficiency of phenanthrene increased with the surfactant concentration. The APG micelles containing phenanthrene easily migrated to the cathode reservoir by EOF. On the other hand, Calfax 16L-35 did not enhance the removal efficiency even at the highest concentration, because most of Calfax 16L-35 remained in soil, and only small amount existed in effluent. It was thought that, during electrokinetic process, Calfax 16L-35 was adsorbed onto soil and the migration of the surfactant from cathode to anode was superior to EOF due to anionic charges of Calfax 16L-35. A nonionic surfactant, APG, seems to be suitable for surfactant-enhanced electrokinetic remediation. [Copyright &y& Elsevier]

Feasibility of micellar-enhanced ultrafiltration for the mixed waste that is consisted of chlorinated aromatic hydrocarbons, nitrate, and chromate was investigated using a cationic surfactant. The co-presence of nitrate and chromate did not significantly affect the removal of chlorobenzenes, and the co-presence of chlorobenzenes did not affect the removal of nitrate and chromate because chlorobenzenes were solubilized at the hydrophobic interior of the micelles by hydrophobic interaction, but nitrate and chromate were bound to the outer shell by electrostatic interaction. Micellar-enhanced ultrafiltration can be applied to treat the mixed wastes. [Copyright &y& Elsevier]

The feasibility of micellar-enhanced ultrafiltration (MEUF) for the removal of nitrate, chromate, and ferric-cyanide was investigated because of ionic competition to bind on the cetylpyridinium chloride micelles. In a single pollutants system, the order of removal efficiency was nitrate

Simultaneous removal of chromate and nitrate, major anionic pollutants in subsurface water system, was investigated using micellar-enhanced ultrafiltration (MEUF) with cetylpyridinium chloride as a cationic surfactant. Rejection of nitrate and chromate was expressed as a function of molar ratio of surfactant to pollutants. With the molar ratio of 1:1:10 (chromate: nitrate: surfactant), rejection of nitrate and chromate reached 80% and 98%, respectively. Rejection of surfactant was observed to be >95% under the same conditions. The rejection of nitrate was inhibited by co-existence of chromate. It was due to the differences in binding power between ionic micelles and counter ions, which is proportional to the valence of counter ions; the valence of chromate was higher than that of nitrate. [Copyright &y& Elsevier]

Feasibility of cross-flow micellar-enhanced ultrafiltration was investigated to remove chromate and nitrate from water system using a cationic surfactant, cetylpyridinium chloride (CPC). Removal of chromate with −2 as valence was higher than that of nitrate with −1 as valence in the conditions of co-existence of chromate and nitrate. Removal of nitrate was significantly inhibited by co-existence of chromate because of competitive binding to CPC micelles between chromate and nitrate, while that of chromate was only slightly inhibited by nitrate. [Copyright &y& Elsevier]

Adult stem cells have been developed as therapeutics for tissue regeneration and immune regulation due to their self-renewing, differentiating, and paracrine functions. Recently, a variety of adult stem cells from the oral cavity have been discovered, and these dental stem cells mostly exhibit the characteristics of mesenchymal stem cells (MSCs). Dental MSCs can be applied for the replacement of dental and oral tissues against various tissue-damaging conditions including dental caries, periodontitis, and oral cancers, as well as for systemic regulation of excessive inflammation in immune disorders, such as autoimmune diseases and hypersensitivity. Therefore, in this review, we summarized and updated the types of dental stem cells and their functions to exert therapeutic efficacy against diseases. [ABSTRACT FROM AUTHOR]

The duplication of the peripheral myelin protein 22 (PMP22) gene causes a demyelinating type of neuropathy, commonly known as Charcot–Marie–Tooth disease type 1A (CMT1A). Development of effective drugs for CMT1A still remains as an unmet medical need. In the present study, we assessed the role of the transforming growth factor beta 4 (TGFβ4)/Nodal axis in the pathogenesis of CMT1A. First, we identified PMP22 overexpression-induced Nodal expression in Schwann cells, which might be one of the downstream effectors in CMT1A. Administration of Nodal protein at the developmental stage of peripheral nerves induced the demyelinating phenotype in vivo. Second, we further isolated TGFβ4 as an antagonist that could abolish Nodal-induced demyelination. Finally, we developed a recombinant TGFβ4–fragment crystallizable (Fc) fusion protein, CX201, and demonstrated that its application had promyelinating efficacy in Schwann cells. CX201 administration improved the demyelinating phenotypes of CMT1A mouse models at both pre-symptomatic and post-symptomatic stages. These results suggest that the TGFβ4/Nodal axis plays a crucial role in the pathogenesis of CMT1A and might be a potential therapeutic target for CMT1A. [ABSTRACT FROM AUTHOR]

While the potential of hydrothermal liquefaction (HTL) of microalgae to produce biocrude regardless of the types of microalgae (biomass-agnostic) has been noted, the quality of biocrude and the Energy Return On Investment (EROI) of HTL of various microalgal species have not been compared in detail. Here we report that the quality of biocrude and the EROI of microalgal HTL are directly dependent on the lipid contents of microalgae. When Nannochloropsis oceanica (30.2% lipid content) and Golenkinia sp. (17.3% lipid content) were compared for the quality of HTL in terms of the total yield, asphaltene/non-asphaltene contents, heteroatom (O, N, and S) concentrations, and the effective hydrogen-to-carbon ratios (H/C eff ) of the biocrudes, N. oceanica with high lipid content produced biocrude that can be more suitable for catalytic upgrading to transportation fuels than the biocrude from Golenkinia sp. with low lipid content. HTL of N. oceanica at low temperature (200 °C) in particular produced the biocrude with EROI that was better than that of Golenkinia sp. These results strongly support that the choice of microalgae with high lipid content is still a key factor that must be considered for biocrude production as much as it is regarded important for biodiesel production using microalgal biomass. [ABSTRACT FROM AUTHOR]

Highlights: [•] A two-stage membrane process with nanofiltration and electrodialysis is proposed. [•] Removal of 5-HMF & levulinic acid (LA) from agarose hydrolysate by nanofiltration. [•] For simultaneous hydrolysate detoxification and 5-HMF & LA recovery. [•] Effective separation of 5-HMF and LA from each other by electrodialysis. [Copyright &y& Elsevier]

Abstract: We report a method for the removal of malachite green (MG) by adsorption and precipitation using nano-sized aminopropyl functionalized magnesium phyllosilicate (AMP) clay. MG, which is used in aquaculture and fisheries, is a carcinogenic and mutagenic compound. In response to these health risks, many efforts have been focused on adsorption of MG onto various adsorbents, which is a versatile and widely used technique for removing MG from water. Herein, we describe the adsorption and precipitation of MG using AMP clay, as well as the alkaline fading phenomenon of MG. In this study, prepared AMP clay and the precipitate product after the reaction of MG–AMP clay mixture were characterized. In addition, adsorption isotherms and kinetics, as well as thermodynamic studies are presented. Based on the results, we suggest a macro- and microscopic removal mechanism for the adsorption and precipitation of MG using AMP clay. An AMP clay dosage of 0.1mgmL−1 exhibited a maximum removal capacity of 334.80mgg−1 and 81.72% MG removal efficiency. With further increases of the AMP clay dosage, removal capacity by AMP clay gradually decreased; at dosage above 0.2mgmL−1 of AMP clay, the removal efficiency reached 100%. [Copyright &y& Elsevier]

Abstract: We describe a facile and simple one-pot synthesis of water-soluble amino-organoclay under ambient conditions. The clay was used to successfully remove environmentally toxic anionic metals, such as arsenate, chromate, and ferricyanide. The electrostatic interactions between the anionic metals and the protonated amino (ammonium) groups of the amino-organoclay resulted in rapid precipitation, within 3min, with a high removal capacity. The maximum removal capacities (in units of mg metal per g organoclay) of the amino-organoclay clay toward HAsO4 2−, CrO4 2−, or Fe(CN)6 3− were, 30.73mg/g, 34.67mg/g, or 218.88mg/g in case of 0.02g, 0.03g, and 0.005g of the amino-organoclay, respectively. The removal efficiencies of 0.07g, 0.09g, and 0.03g of the amino-organoclay whose dosage of clay was at the highest removal efficiency (%) for arsenate, chromate, and ferricyanide, respectively, presented 59.79%, 89.54%, and 97.43%. Furthermore, humic acid that ubiquitous in the organic matter present in water or soil environments, inhibited the removal rate of anionic metals, and thus the removal efficiencies toward all anionic metals were markedly reduced. Humic acid preferentially precipitated with the interaction of amino-organoclay prior to the anionic metals. [Copyright &y& Elsevier]

Abstract: We carried out electrokinetic remediation with electrolyte conditioning and pretreatment using acidic and basic solutions to remediate Cu-, As-, and Pb-contaminated soil on a laboratory scale. Under given conditions the soil pH was made more acidic or more basic, and the pH change influenced the strength of the binding of metals and metalloids onto the soil surface. Catholyte conditioning using an acidic solution increased the removal of Cu and Pb from the soil, and the maximum removal was 60.1% for Cu and 75.1% for Pb. Anolyte conditioning using a basic solution enhanced the transport of arsenic (As), which exists in an anionic form. Even though most of the As was strongly bound to the soil matrix in a residual form (≥95%), 43.1% was removed by electrokinetics under anolyte conditioning with a basic solution. Simultaneous removal was attempted via a change in the purging solution. However, blocking phenomena occurred because of the sudden pH change of the electrolyte from acidic to basic, and the electrokinetic transport of the ionic species was interrupted in the soil compartment. Thus, catholyte or anolyte conditioning removed cationic or anionic metals from the soil, but the simultaneous removal of both was not achieved, and a sudden change in the conditioning solution caused precipitation of metal hydroxides and blocking of the pores. [Copyright &y& Elsevier]

Abstract: In electrokinetic-Fenton (EK-Fenton) process, the effects of the phosphate and SDS introduced from the anode chamber were investigated for the treatment of clay contaminated with phenanthrene. In tests with phosphate and SDS, the electrochemical phenomena were complicate trend compared to tests with HCl. These results resulted from complexation of phosphate with oxides and SDS, and then increase of dissolved SDS concentration with pH increase in regions near cathode. The electro-osmotic flow increased as zeta-potential on the soil surface decreased due to complexation of phosphate and SDS with oxides. In test with phosphate, the transportation of dissolved Fe ions toward the cathode was hindered significantly due to complexation with phosphate. However, in test with SDS, the dissolved Fe ions could be transported in the regions near cathode compared to test with phosphate. These results indicate that SDS dissolved the Fe ion from Fe oxide of soil structure and then the dissolved Fe ions with SDS as counter ion could be transported in regions near cathode. Furthermore, transition metal complexation with phosphate and SDS generated improvement of H2O2 stability. Particularly, in test with SDS, the improvement of H2O2 stability in high pH regions resulted from SDS transportation in regions near cathode. Consequently, in EK-Fenton process with longer reaction time, the increase of H2O2 stability resulted in increase of phenanthrene treatment efficiency. [Copyright &y& Elsevier]

Abstract: The polyelectrolyte enhanced ultrafiltration (PEUF) process for perchlorate removal from groundwater containing common co-contaminants like nitrate and sulfate was investigated. Existing processes such as ion exchange can remove perchlorate but with greater complexity, especially when applied in the presence of high nitrate and sulfate concentration. The effect of cationic polyelectrolyte, poly(diallyldimethyl ammonium chloride) (PDADMAC) concentration and the effect of nitrate and sulfate in a broader concentration range were observed. In the absence of other anions, a lower amount of PDADMAC (0.5–1 mM) can remove more than 90% of perchlorate from the aqueous phase. However, in the presence of 5 mM nitrate, perchlorate removal decreases as the available binding sites of PDADMAC for perchlorate are reduced. In the presence of both 1 mM to 10 mM nitrate and sulfate, 60–80% perchlorate was removed with 30 mM PDADMAC. The removal of sulfate and nitrate in this case was nearly 75% and 65%, respectively. The effect of other parameters such as relative flux, membrane material and pore size were also observed to study the feasibility of PEUF for perchlorate removal. Consequently, PEUF proved to be an effective perchlorate removal process owing to the high removal efficiency and suitability in groundwater remediation containing other contaminants. [Copyright &y& Elsevier]

Abstract: LiCoO2 powders for lithium secondary battery were successfully prepared by the ultrasonic spray pyrolysis process. In this work, the statistical experimental design method was used to compare the characteristics (particle size, standard deviation, surface area, tab density) of the LiCoO2 particles according to the four parameters (synthesis temperature, sintering temperature, sintering time, sintering heating rate). The optimal synthesis conditions for the synthesis of LiCoO2 particles in ultrasonic spray pyrolysis process were to be obtained. The above-mentioned optimal conditions were used to prepare the particles with particle size 4.7μm (standard deviation: ±1.3%) and the experimental results were in a good agreement with simulated values. The oxide powders were characterized by scanning electron microscopy, X-ray diffraction and electrochemical method including charge–discharge cycling. The characteristics as a cathode for lithium ion battery depended on the sintering temperature and sintering time. Consequently, LiCoO2 powders made by the ultrasonic spray pyrolysis process displayed a good electrochemical performance and the experimental design method was well applied. [Copyright &y& Elsevier]

Abstract: Ultrafiltration has been used as an effective process to remove heavy metals and organic pollutants from contaminated-groundwater and wastewater or as a part of surfactant-enhanced aquifer remediation (SEAR) process to concentrate and reuse the surfactant. The objective of this study was to investigate the effects of surfactant types, hydrophile–lipophile balance (HLB), salt amount, humic acid, and clay on the ultrafiltration: permeate concentration and flux. The regenerated cellulose membrane of 10K MWCO was used throughout the experiment. The flux was dependent on the viscosity of surfactant solution and water solubility of surfactant. Higher viscosity and lower water solubility caused the decrease of flux. The permeate concentration of surfactant was a function of the critical micelle concentration of surfactant. In the case of anionic surfactants, the permeate concentration decreased as salts concentration increased. The lower of HLB value caused the flux decline and higher concentration of permeate. Humic acid and clay decreased the flux. The permeate concentration of surfactant was not significantly influenced by the existence of humic acid and clay. [Copyright &y& Elsevier]

Abstract: The synthesis of spherical hollow silica particles from sodium silicate solution with boric acid or urea as an additive was carried out by ultrasonic spray pyrolysis method. This work dealt with the effect of four parameters (boric acid, urea, feed rate of reactant, and reaction temperature) on particle size and standard deviation. As a result, the mean particle size and standard deviation decreased with increasing of all parameters except urea. In addition, silica particles with a variety of morphologies were prepared by varying the amount of boric acid and urea. Spherical particles with a smooth surface were prepared at the small concentration of boric acid (0.13–0.18molel-1) without urea. On the other hand, as the concentration increased (0.40–0.48molel-1), the surface of particles became rough and porous condition. In addition, when a small amount of urea (0.07–0.15molel-1) was used, the spherical hollow silica particles were obtained. However, as the concentration increased (0.40–0.71molel-1), broken hollow silica particles with broad particle size distribution were synthesized. [Copyright &y& Elsevier]

The immobilization behavior of methyl tert-butyl ether (MTBE) by various cyclodextrins (CDs) was studied. Although it has a low hydrophobic character and high polarity compared to other organics, MTBE was effectively immobilized by CDs. The immobilization isotherm was a type of Freundlich isotherm. The immobilization capacity of β-CDs was the largest of the natural CDs. The initial apparent association constant for MTBE–CD complex follows the order: γ = β > methyl-β > hydroxypropyl β > α. The difference in these constants is related to the size of MTBE and CDs. The size of β- and γ-CD is large enough to encapsulate MTBE molecule into the cavity, which that of α-CD is too small to encapsulate MTBE. [Copyright &y& Elsevier]

Feasibility of micellar-enhanced ultrafiltration was investigated to study simultaneous removal of ferric cyanide and nitrate with a cationic surfactant, cetylpyridinium chloride (CPC). The removal of ferricyanide and nitrate was studied as a function of surfactant to ferricyanide/nitrate molar ratios. In the ferricyanide/CPC and nitrate/CPC systems, the removal of ferricyanide and nitrate increased gradually as the molar ratio of CPC to ferricyanide or nitrate increased. With a 10 molar ratio of CPC, the removal of ferricyanide and nitrate increased to >99.9% and 93%, respectively. In the ferricyanide/nitrate/CPC system, the removal of ferricyanide increased from 62% to 72% and to 99.9%, while that of nitrate from <2% to <2% and to 27% as the molar ratio of ferricyanide:nitrate:CPC increased from 1:1:1 to 1:1:2 and to 1:1:4, respectively. With the molar ratio of 1:1:10, the removals were >99.9% and 78% for ferricyanide and nitrate, respectively. Ferricyanide ions were more easily bound to CPC micelles because the binding power of ferricyanide was greater than that of nitrate. With the difference of binding power, selective removal of ferricyanide using micellar-enhanced ultrafiltration could be achieved. [Copyright &y& Elsevier]

The feasibility of micellar-enhanced ultrafiltration to remove nutrients, nitrate and phosphate, was investigated with a cationic surfactant, cetlypyridinium chloride (CPC). The effects of surfactant molar ratios on the rejection of nitrate and phosphate and flux decline were studied. In the nitrate/phosphate/CPC system, as the molar ratio of nitrate: phosphate:CPCincreasedfrom 1:0.06:1.06to 1:0.06:3.18andto 1:0.06:5.30,therejectionofnitrateincreased from 77% to 84% andto 92%, while phosphate rejection increased from 83% to 87% and 95%, respectively. The rejection ofCPC increased as the molar ratio increased, and the concentration of CPC in the permeate was negligible because the size of the CPC micelle was lager than the pore size of the membrane, which indicated that the secondary pollution by surfactants might be insignificant. The reduction of permeate flux induced by the addition of a surfactant was due to the gel layer formed on the surface of the membrane. [Copyright &y& Elsevier]

Corneal chemical burns can lead to blindness following serious complications. As most of these complications are caused by failure of reepithelization during the acute phase, treatment at this stage is critical. Although there have been some studies on corneal injury recovery using adipose tissue-derived stem cells (ADSCs), none has reported the effect of topical cell-free conditioned culture media (CM) derived from ADSCs on corneal epithelial regeneration. Here, the best conditions for CM were selected and used for in vitro and in vivo experiments. Corneal burn in rats was induced using 100% alcohol. The chosen CM was administered to corneal burn rats (CM-treated [CT] group) four times a day for three days and this group was compared with the normal control and corneal burn (CB) groups. Biomicroscopic fluorescence images and the actual physical corneas were taken over time and used for analysis. mRNA levels of hepatocyte growth factor and epidermal growth factor (EGF) were significantly increased, whereas those of vascular endothelial growth factor, interleukin (IL)-1β, IL-6, IL-10, and matrix metalloproteinase-9 were significantly decreased in the CT group compared with those in the CB group. The numbers of proliferating cell nuclear antigen- and zonular occludens-1-positive cells in the CT group were significantly higher than those in the CB group. The macrophage-infiltrating corneas in the CT group expressed significantly more of the M2 marker arginase than corneas in the CB group. Optimal CM (× 0.5 concentration) treatment significantly accelerated the migration of corneal epithelial cells and induced upregulation of the expression of IL-6, EGF, and C-X-C chemokine receptor type 4 mRNAs. Overall, in this study, topical administration of cell-free CM promoted regeneration of the corneal epithelium after induction of chemical burns. [ABSTRACT FROM AUTHOR]

Abstract The feasibility of a carbon recycling system that transforms algal residue to volatile fatty acids (VFAs) for re-cultivating microalgae was evaluated based on a carbon balance analysis of major VFAs consisting of acetate (HAc), propionate (HPr), and butyrate (HBu). This system largely involves two processes: (i) bioconversion of algal residue to VFAs by anaerobic fermentation, and (ii) cultivation of microalgae using the produced VFAs. The carbon balance for each unit process was examined to assess how much carbon in algal residue can be converted to these major VFAs and then assimilated to microalgae biomass. First, the yield and the profile of VFAs from raw algae (RA) and lipid-extracted algae (LEA) at psychrophilic (15 °C), mesophilic (35 °C), and thermophilic conditions (55 °C) were compared. When digesting the LEA under the thermophilic condition, the highest conversion yield, 0.36 (g carbon in VFAs/g carbon in biomass), with a compositional ratio of 6:1:3 (HAc: HPr: HBu) was obtained. Consumption of VFAs for microalgal growth reached a maximum value of 0.66 (g VFAs assimilated to biomass/g VFAs provided) at the compositional ratio of 6:1:3. Consequently, the maximum total carbon recycling ratio was 23.8% when fermenting LEA at the thermophilic condition. Our findings comprehensively revealed that establishing conditions that convert LEA to higher content of acetate is a decisive factor. It was estimated that around 40% of the total carbon from the LEA can be recovered for the production of algal biomass, when increasing the VFA conversion yield beyond 60% by adopting pretreatment methods. Highlights • A carbon recycling system of microalgal residue via VFAs platform was evaluated. • Thermophilic anaerobic fermentation exhibited the highest carbon conversion yield. • The higher algal growth was proportional to the higher acetate content. • Acetate was a major carbon carrier for total carbon recycling in the whole system. • The VFAs yield of anaerobic fermentation is a key factor for carbon recycling. [ABSTRACT FROM AUTHOR]

This study examined the feasibility of using an algal-bacterial process for removal of phenol and NH 4 + -N from differently diluted coke wastewater with simultaneous production of biomass. Under illumination, microalgal-bacterial (MSB) cultures performed complete phenol degradation at all dilutions of coke wastewater while sole microalgal culture (MSA) degraded a maximum of 27.3% of phenol (initial concentration: 24.0 mg L −1 ) from 5-fold diluted wastewater. Furthermore, the MSB culture had the highest rate of NH 4 + -N removal (8.3 mg L −1 d −1 ) and fatty acid production (20 mg L −1 d −1 ) which were 2.3- and 1.5-fold higher than those observed in the MSA cultures, probably due to decreases in toxic organic pollutants. Multivariate analyses indicated that co-cultivation of activated sludge was directly correlated with the elevated removals of phenol and NH 4 + -N. In the presence of sludge, adequate dilution of the coke wastewater can maximize the effect of bacteria on NH 4 + -N removal and biomass production. [ABSTRACT FROM AUTHOR]

In this study, we investigated phenol degradation via zero-valent iron (ZVI)-assisted Fenton reaction through kinetic and spectroscopic analysis. In batch experiments, 100 mg/L of phenol was completely degraded, and 75% of TOC was removed within 3 min under an optimal hydrogen peroxide (H 2 O 2 ) concentration (50 mM) via the Fenton reaction. In the absence of H 2 O 2 , oxygen (O 2 ) was dissolved into the solution and produced H 2 O 2 , which resulted in phenol degradation. However, phenol removal efficiency was not very high compared to external H 2 O 2 input. The Fenton reaction rapidly occurred at the surface of ZVI, and then phenol mobility from the solution to the ZVI surface was the rate determining step of the whole reaction. The pseudo-second order adsorption kinetic model well describes phenol removal, and its rate increased according to the H 2 O 2 concentration. X-ray absorption spectroscopic analysis revealed that iron oxide (Fe–O bonding) was formed on ZVI with [H 2 O 2 ] > 50 mM. A high concentration of H 2 O 2 led to rapid degradation of phenol and caused corrosion on the ZVI surface, indicating that Fe 2+ ions were rapidly oxidized to Fe 3+ ions due to the Fenton reaction and that Fe 3+ was precipitated as iron oxide on the ZVI surface. However, ZVI did not show corroded characteristics in the absence of H 2 O 2 due to the insufficient ZVI-assisted Fenton reaction and oxidation of Fe 2+ to Fe 3+ . [ABSTRACT FROM AUTHOR]

Five technologies, coagulation, electro-flotation (EF), electro-coagulation–flotation (ECF), centrifugation, and membrane filtration, were systematically assessed for their adequacy of harvesting Aurantiochytrium sp. KRS101, a heterotrophic microalgal species that has much higher biomass concentration than photoautotrophic species. Coagulation, EF, and ECF were found to have limited efficiency. Centrifugation was overly powerful to susceptible cells like Aurantiochytrium sp. KRS101, inducing cell rupture and consequently biomass loss of over 13%. Membrane filtration, in particular equipped with an anti-fouling turbulence generator, turned out to be best suited: nearly 100% of harvesting efficiency and low water content in harvested biomass were achieved. With rotation rate increased, high permeate fluxes could be attained even with extremely concentrated biomass: e.g., 219.0 and 135.0 L/m 2 /h at 150.0 and 203.0 g/L, respectively. Dynamic filtration appears to be indeed a suitable means especially to obtain highly concentrated biomass that have no need of dewatering and can be directly processed. [ABSTRACT FROM AUTHOR]

Algal technology has potential to combat the global energy crisis, malnutrition, and production of several value added products useful for the mankind. The cost effective cultivation system is the basis to realize this goal. Microalgal production in raceway ponds seems to be most promising, especially in the large scale. Several environmental (location of the cultivation system, rainfall, solar radiation, etc.), engineering (pond depth, CO 2 delivery system, methods of mixing, power consumption, etc.), and biological (light, pH, oxygen accumulation, salinity, Algal predators etc.) parameters affect the biomass productivity in the open pond system. Vertical mixing is an important criteria influencing the algal growth compared to axial mixing as it determines the frequency by which cell will travel from bottom (dark zone) to surface (light zone) of the open pond. Therefore, different research works on the various designs of raceway ponds were mostly focused towards enhancing the vertical mixing (e.g. Design of bend and surface geometry, engineering flow field, etc.) and CO 2 residence time (e.g. Closed, sump, airlift driven raceway ponds etc.). The present study summarizes the current state of knowledge for the biomass production in raceway ponds. [ABSTRACT FROM AUTHOR]

Changes in algal and bacterial communities during thiocyanate (SCN − ) decomposition in a microalga-mediated process were studied. Pyrosequencing indicated that Thiobacillus bacteria and Micractinium algae predominated during SCN − hydrolysis, even after its complete degradation. Principal components analysis and evenness profiles (based on the Pareto–Lorenz curve) suggested that the changes in the bacterial communities were driven by nitrogen and sulfur oxidation, pH changes, and photoautotrophic conditions. The populations of predominant microalgae remained relatively stable during SCN − hydrolysis, but the proportion of bacteria – especially nitrifying bacteria – fluctuated. Thus, the initial microalgal population may be crucial in determining which microorganisms dominate when the preferred nitrogen source becomes limited. The results also demonstrated that microalgae and SCN − -hydrolyzing bacteria can coexist, that microalgae can be effectively used with these bacteria to completely treat SCN − , and that the structure of the algal-bacterial community is more stable than the community of nitrifying bacteria alone during SCN − degradation. [ABSTRACT FROM AUTHOR]

This work describes the development of a microalga-mediated process for simultaneous removal of residual ammonium nitrogen (NH 4 + -N) and production of lipids from biologically treated coke effluent. Four species of green algae were tested using a sequential mixotrophic process. In the first phase—CO 2 -supplied mixotrophic condition—all microalgae assimilated NH 4 + -N with no evident inhibition. In second phase—volatile fatty acids (VFAs)-supplied mixotrophic condition—removal rates of NH 4 + -N and biomass significantly increased. Among the microalgae used, Arctic Chlorella sp. ArM0029B had the highest rate of NH 4 + -N removal (0.97 mg/L/h) and fatty acid production (24.9 mg/L/d) which were 3.6- and 2.1-fold higher than those observed under the CO 2 -supplied mixotrophic condition. Redundancy analysis (RDA) indicated that acetate and butyrate were decisive factors for increasing NH 4 + -N removal and fatty acid production. These results demonstrate that microalgae can be used in a sequential process for treatment of residual nitrogen after initial treatment of activated sludge. [ABSTRACT FROM AUTHOR]

In this work, the effects of several factors, such as temperature, reaction time, and solvent and acid quantity on in situ transesterification yield of wet Nannochloropsis salina were investigated. Under equivalent total solvent volume to biomass ratio, pure alcohol showed higher yield compared to alcohol–chloroform solvent. For esterifying 200 mg of wet cells, 2 ml of methanol and 1 ml of ethanol was sufficient to complete in situ transesterification. Under temperatures of 105 °C or higher, 2.5% and 5% concentrations of sulfuric acid was able to successfully convert more than 90% of lipid within 30 min when methanol and ethanol was used as solvents respectively. Also, it was verified that the optimal condition found in small-scale experiments is applicable to larger scale using 2 L scale reactor as well. [ABSTRACT FROM AUTHOR]

Triiodide resin (TR) was used to generate axenic cultures of microalgae by employing the antibacterial capability of triiodide. A Nannochloropsis gaditana culture contaminated with bacteria was passed through a column filled with TR using the gravity flow. Based on analyses of flow cytometry and vital staining using a fluorescent dye SYTOX Green, three cycles of TR treatments remarkably reduced the number of viable bacteria but had little effects on the microalgae. This novel approach is a simple, rapid, and cost-effective method that can be used to isolate axenic cultures of microalgae. [ABSTRACT FROM AUTHOR]

Microalgal biofuels are not yet economically viable due to high material and energy costs associated with production process. Microalgae cultivation is a water-intensive process compared to other downstream processes for biodiesel production. Various studies found that the production of 1 L of microalgal biodiesel requires approximately 3000 L of water. Water recycling in microalgae cultivation is desirable not only to reduce the water demand, but it also improves the economic feasibility of algal biofuels as due to nutrients and energy savings. This review highlights recently published studies on microalgae water demand and water recycling in microalgae cultivation. Strategies to reduce water footprint for microalgal cultivation, advantages and disadvantages of water recycling, and approaches to mitigate the negative effects of water reuse within the context of water and energy saving are also discussed. [ABSTRACT FROM AUTHOR]

An interest in biodiesel as an alternative fuel for diesel engines has been increasing because of the issue of petroleum depletion and environmental concerns related to massive carbon dioxide emissions. Researchers are strongly driven to pursue the next generation of vegetable oil-based biodiesel. Oleaginous microalgae are considered to be a promising alternative oil source. To commercialize microalgal biodiesel, cost reductions in oil extraction and downstream biodiesel conversion are stressed. Herein, starting from an investigation of oil extraction from wet microalgae, a review is conducted of transesterification using enzymes, homogeneous and heterogeneous catalysts, and yield enhancement by ultrasound, microwave, and supercritical process. In particular, there is a focus on direct transesterification as a simple and energy efficient process that omits a separate oil extraction step and utilizes wet microalgal biomass; however, it is still necessary to consider issues such as the purification of microalgal oils and upgrading of biodiesel properties. [ABSTRACT FROM AUTHOR]

The oleaginous microalga Nannochloropsis sp. has been spotlighted as a promising candidate in genetic engineering research for biodiesel production. However, one of the major bottlenecks in the genetic manipulation against Nannochloropsis sp. is low transformation efficiency. Based on the idea that they grow rapidly in broth culture, the effect of conditioned medium on colonization and transformation efficiency of Nannochloropsis salina was investigated. Cells grown on agar plates with 20–40% conditioned medium produced colonies that were approximately 2.3-fold larger than cells grown without conditioned medium. More importantly, the transformation efficiency was about 2-fold greater on plates with 30% conditioned medium relative to those without conditioned medium. In addition, FAME productivity in liquid cultures with 100% conditioned medium increased up to 20% compared with cultures of control medium. These results suggest that conditioned medium can be applied for efficient transformation and cost-effective cultivation of N. salina for biodiesel production. [ABSTRACT FROM AUTHOR]

A dynamic microfiltration system has been receiving increasing attention as a means of preventing membrane fouling phenomena that reduce microalgae harvesting efficiency. This study describes the addition of a perforated disk to a dynamic microfiltration system for effective membrane-based microalgae harvesting. Fluid velocity near the membrane surface and shear stress on the membrane surface, as generated by different disks and rotation speeds, were simulated by computational fluid dynamics software, SolidWorks. A high correlation of shear stress on the membrane with microalgae harvesting efficiency was validated by a simulation-based empirical approach. Notably, fluid velocity near the membrane surface and average shear stress on the membrane surface with the perforated disk were approximately 2- and 7-fold, respectively, higher than observed with an unperforated disk. In empirical-experimental microfiltration of Chlorella vulgaris , the perforated disk (800 rpm) showed a 2-fold-higher plateau permeate flux of 381 L/m 2 /h compared with the unperforated disk (800 rpm), enabling a 2-fold-greater alleviation of microalgal fouling at the same rotation speed. The perforated disk was found to be an effective generator of high shear stress in dynamic microfiltration, resulting in improved filtration during harvesting of microalgae. [ABSTRACT FROM AUTHOR]

In this study, we prepare low-cost adsorbents from paper industry waste (newspaper (NP) and white paper (WP) waste) through a simple drying process and used them for Pb(II) removal. Characteristics, maximum Pb(II) removal capacities of prepared adsorbents, and Pb(II) removal mechanisms are investigated. The maximum amounts of adsorbed Pb(II) on NP and WP derived from the Langmuir isotherm are 42.4 and 18.5 mg·g−1, respectively. This value is similar or more effective than commercial and other low-cost Pb(II) sorbents. It indicates that low-cost adsorbents prepared from paper industry waste have high potential as inexpensive and effective heavy metal adsorbents. [ABSTRACT FROM AUTHOR]

Mass cultivation of microalgae is necessary to achieve economically feasible production of microalgal biodiesel, but the high cost of nutrients is a major limitation. In this study, orange peel extract (OPE) was used as an inorganic and organic nutrient source for the cultivation of Chlorella vulgaris OW-01. Chemical composition analysis of the OPE indicated that it contains sufficient nutrients for mixotrophic cultivation of C. vulgaris OW-01. Analysis of biomass and FAME production showed that microalgae grown in OPE medium produced 3.4-times more biomass and 4.5-times more fatty acid methyl esters (FAMEs) than cells cultured in glucose-supplemented BG 11 medium (BG-G). These results suggest that growth of microalgae in an OPE-supplemented medium increases lipid production and that OPE has potential for use in the mass cultivation of microalgae. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nutrient from algal hydrolysate showed excellent growth profile in Ettlia sp. [•] Organic carbon from SFW significantly increased lipid content. [•] Cells cultivated under AH and SFW showed improvement in FAME profile. [ABSTRACT FROM AUTHOR]

Highlights: [•] Degrading the thiocyanate and producing lipids were achieved by algal–bacterial culture. [•] Two-mode was sequentially employed: a photoauto- and photoheterotrophic mode. [•] Significant increase of lipids was observed under photoheterotrophic condition. [•] Statistical methodology was used to evaluate the effects of organic substrates on lipid. [Copyright &y& Elsevier]

Highlights: [•] Acid-catalyzed hot-water treatment for lipid extraction from wet microalgae. [•] The optimal lipid-extraction condition of 1.00% sulfuric acid concentration. [•] Extraction of docosahexaenoic acid (DHA)-rich lipids from Aurantiochytrium sp. [Copyright &y& Elsevier]

Highlights: [•] Structural correlation between cellular development and lipid body accumulation. [•] HTP screening of thraustochytrid using FACS with different fluorescent dyes. [•] Found that BODIPY 505/515 with less concentration of DMSO effective for FACS. [•] Established a quantitative baseline for lipids accumulation and/or microalgal growth. [Copyright &y& Elsevier]

Highlights: [•] Nannochloropsis gaditana was cultivated under white, blue or red light. [•] Biomass accumulation was 1.43-fold higher under red than under white light. [•] FAME yield was twofold higher under red light than under white light. [•] Red light increased photosynthetic efficiency, carbon fixation and nutrient uptake. [•] Red light illumination is a simple method for lipid induction by N. gaditana. [ABSTRACT FROM AUTHOR]