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Agricultural environment is often contaminated with various chemicals (e.g., pesticides, heavy metals) and microplastics due to the uses of plastic products. The effects of chemical contaminants or microplastics on terrestrial environment have been extensively studied, but the studies on the co-presence of chemical contaminants and microplastics are relatively limited. This study was set to investigate the effect of co-presence of microplastics (i.e., low-density polyethylene (LDPE) and polyvinyl chloride (PVC) microplastic films) and chemical contaminants (i.e., cadmium (Cd) and procymidone (PCM)) in soil on the lettuce growth and Cd and PCM uptake by lettuce using pot tests. The lettuce leaf lengths were not affected by the presence of only Cd or PCM, but the rates of change in the lettuce leaf number were adversely affected by the presence of PCM. The presence of only LDPE or PVC in soil at the concentrations used in this study did not have significant impacts on the lettuce growth. But the co-presence of Cd and LDPE and the co-presence of PCM and PVC resulted in the negligible increases in the lettuce leaf length and leaf number with time, although the lettuce growths were statistically similar in the Cd- or PCM-contaminated soils regardless of the presence of microplastics. The results suggest that the adverse effects of Cd or PCM can be intensified by the co-presence of microplastics, and the effects can be different depending on the types of microplastics. The promoted adverse effects of chemical contaminants in the co-presence of microplastics can be supported by the tendency of the increased absorption of Cd or PCM by lettuce in the co-presence of microplastics. Overall, this study shows the need for management of both chemical contaminants and microplastics that may reside in the agricultural environment. [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]

Procymidone (PCM), an agricultural fungicide, is attracting attention because it has been detected in all ecosystems, including aquatic environments. This study explored changes in the behavior and toxicity of PCM in water under the influence of photolysis and microplastics (MPs) coexistence. Hydrolysis of PCM was evaluated and UV-A and UV-C lamps were used as light sources for the photodegradation experiments. The Microtox® assay was used to evaluate changes in toxicity during the photodegradation and after sorption on MPs of low-density polyethylene (LDPE) and polyvinyl chloride (PVC) films. The appearance of 3,5-dichloroaniline (DCA), a major metabolite of PCM that is more toxic than its parent compound in water, was confirmed. Both PCM and DCA showed sufficient molar extinction coefficients to be photolyzed under UV-C irradiation (εPCM=10,300 M−1 cm−1 and εDCA=2,400 M−1 cm−1); however, the presence of natural organic matter negatively affected their photodegradation. PVC showed a better sorption potential for PCM and DCA than for LDPE. The higher sorption by PVC significantly reduced the toxic effect of DCA from an average value of 79% to 60% and increased the EC50 value from 30.4% to 47.6%. These results offer insights into controlling toxic micropollutants, including fungicides, in aquatic environments and water treatment processes. [ABSTRACT FROM AUTHOR]

Ethanol was produced by separate hydrolysis and fermentation using Azolla filiculoides as a biomass. Thermal acid hydrolysis and enzymatic saccharification were used as pretreatment methods to produce monosaccharides from Azolla. The optimal content for thermal acid hydrolysis of 14% (w/v) Azolla weed slurry produced 16.7-g/L monosaccharides by using 200 mM H2SO4 at 121 °C for 60 min. Enzymatic saccharification using 16 U/mL Viscozyme produced 61.6 g/L monosaccharide at 48 h. Ethanol productions with ethanol yield coefficients from Azolla weed hydrolysate using Kluyveromyces marxianus, Candida lusitaniae Saccharomyces cerevisiae, and Pichia stipitis were 26.8 g/L (YEtOH = 0.43), 23.2 g/L (YEtOH = 0.37), 18.2 g/L (YEtOH = 0.29), and 13.7 g/L (YEtOH = 0.22), respectively. Saccharomyces cerevisiae produces the lowest yield as it utilized only glucose. Bioethanol from Azolla weed hydrolysate can be successfully produced by using Kluyveromyces marxianus because it consumed the mixture of glucose and xylose completely within 60 h. [ABSTRACT FROM AUTHOR]

Background: Writing is a useful learning activity that promotes higher-order thinking, but there are limited studies that prove its effectiveness. In previous research, researchers tested the effect of summary writing on students' comprehension and found no significant difference from that of re-studying texts. The purpose of this study, therefore, is to expand previous findings and investigate the effect of two types of writing tasks on medical students' academic performance, specifically in the transfer of knowledge. Methods: An experiment was conducted with 139 medical students from Seoul National University College of Medicine. They were randomly assigned to three study conditions: self-study (SS), expository writing (EW), and argumentative writing (AW) group. Each group studied the given material by the method they were assigned, and they were tested on their comprehension and transfer of knowledge using rote-memory type items and transfer type items respectively. Results: The results showed that the two writing groups displayed better performance than the SS group in transfer type items, while there was no difference in scores between the EW and AW group. However, the three groups showed no significant difference in their scores for rote-memory type items. Also, there was a positive correlation between the writing scores and transfer type item scores in the AW group. Conclusions: This study provides empirical evidence for writing to be adopted in medical education for greater educational benefits. Our findings indicate that writing can enhance learning and higher-order thinking, which are critical for medical students. [ABSTRACT FROM AUTHOR]

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]

Background: The ICAP framework based on cognitive science posits four modes of cognitive engagement: Interactive, Constructive, Active, and Passive. Focusing on the wide applicability of discussion as interactive engagement in medical education, we investigated the effect of discussion when it was preceded by self-study and further investigated the effect of generating questions before discussions. Methods: This study was conducted in the second semester of 2018 and was participated in by 129 students majoring in health professions, including medicine, dentistry, veterinary medicine, and nursing. The students were assigned to four different trial groups and were asked to fill out a Subjective Mental Effort Questionnaire after completing each session. Their performance in posttest scores was analyzed using Bonferroni test, and mental effort was analyzed using mediation analysis. Results: These results indicated that the self-study and question group had the highest performance and that the lecture and summary group had the lowest performance when comparing the total score. Using the analysis of mental effort, it was confirmed that the relationship between different study conditions and post-test performance was mediated by mental effort during test. Conclusions: Our findings support the ICAP framework and provide practical implications for medical education, representing the fact that students learn more when they are involved in active learning activities, such as self-study and question generation, prior to discussions. [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]

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Bis(phenylsulfone) was developed as a strong electron acceptor of thermally activated delayed fluorescent emitters. The connection of two electron withdrawing phenylsulfone moieties through meta-position of phenyl produced the bis(phenylsulfone) acceptor and the strong electron acceptor strength of bis(phenylsulfone) enabled preparation of sky-blue and green thermally activated delayed fluorescent emitters in combination with weak carbazole donors. The bis(phenylsulfone) acceptor and carbazole donor combined organic materials performed as thermally activated delayed fluorescent emitters with a high quantum efficiency of 18.3%. [ABSTRACT FROM AUTHOR]

ABSTRACT Gasification of microalgae feedstock generates mineral ash. In this work, raw ash is produced from lipid-extracted algal biomass of the Nannochloropsis salina strain. Prior to using it as filler for composite fabrication with poly(vinyl alcohol), raw ash (RASH) is activated with NaOH and surface modified with (3-aminopropyl)triethoxysilane. Surface modification of activated ash (PASH) significantly improves interfacial interaction between surface-modified ash (GASH) and polymer matrix. Higher ultimate tensile strength of PVA/GASH composites is recorded, compared with PVA/RASH and PVA/PASH. Young's modulus of biocomposites appears to increase proportionally to loading of the fillers. Thermal properties of polymeric materials of PVA with these ashes are stable. This is the first report to demonstrate the utilization of microalgal ash, the leftover after completed gasification of algal biomass, as an efficient filler for production of value-added polymeric materials. It is proposed that microalgal ash is capable of improving the economic feasibility of microalgae-based biorefinery. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43599. [ABSTRACT FROM AUTHOR]

Malachite green (MG) has been widely used in the dyeing industry and as a fungicide and an antiseptic in the aquaculture industry. However, MG is very dangerous and cytotoxic to mammalian cells, and its discharge into receiving waters results in environmental problems in aquatic ecosystems. To remove this soluble dye from aqueous solutions, adsorption by inorganic clay is often used. In the case of the triphenylmethane dye family, molecular structure changes occur with changes in pH. As a result, chromatic MG+at a neutral pH turns into the protonated MG (MGH2+) at an acidic pH and into the carbinol base form at a basic pH. In this study, taking into consideration the potential for MG structural change, batch sorption experiments for kinetics (5–1.17, 10–2.94, and 20–5.90 MG mg/mL at 293, 303, and 313 K) and thermodynamics (calculated activation energy (Ea) = 2.09 kJ/mol) as well as tests of the feasibility of column flushing were conducted using talc to remove MG from aqueous solutions (100% removal after 140 pore volumes of a 12-h run). We studied specific removal behaviors of MG by talc for pH values > 8.0, where MG molecules that had adsorbed onto the talc predominantly changed to the carbinol base form and were retained on the talc. [ABSTRACT FROM PUBLISHER]

Spirulina is one of the promising photosynthetic microorganisms as the source for food, cosmetic, and other value-added products such as phycocyanin. However, its production cost associated with cultivation is expensive because of high concentration of bicarbonate (76wt%) in standard Zarrouk medium for Spirulina. Bicarbonate not only acts as a carbon source but also helps maintaining culture medium in alkaline condition, which is essential for growth of Spirulina. The present study demonstrates that bicarbonate (16.8 g/L) in standard Zarrouk medium was completely replaceable by chemical CO absorption using 0.2M NaOH and 154.2 mmol CO gas could be absorbed in the form of NaHCO/NaCO into 1 L medium during the process. This process was incorporated into Spirulina cultivation, which enabled us to reduce the total cost of preparation of Zarrouk medium by 34.3% without sacrificing biomass and pigments production. In addition, another important use of NaOH is achievement of cost-efficient and ecofriendly sanitization of culture medium. [ABSTRACT FROM AUTHOR]

Bicarbazole derivatives, 9,9′-bis(dibenzo[b,d]thiophen-2-yl)-9H,9′H-3,3′-bicarbazole (BCzDBT), 9,9′-bis(dibenzo[b,d]furan-2-yl)-9H,9′H-3,3′-bicarbazole (BCzDBF), and 9,9′-di([1,1′-biphenyl]-3-yl)-9H,9′H-3,3′-bicarbazole (BCzBP), were designed and examined as the hole transport type host materials of the tris[1-(2,4-diisopropyldibenzo[b,d]furan-3-yl)-2-phenylimidazole] (Ir(dbi)3) blue triplet emitter. BCzDBT performed better than BCzDBF and BCzBP as the hosts of Ir(dbi)3 and could demonstrate 24.8% quantum efficiency and long lifetime in the blue phosphorescent devices. Strong hole carrying properties of the bicarbazole derivatives were proposed as the main factors for the high quantum efficiency of the BCzDBT devices, and thermal and chemical stability of BCzDBT were suggested as crucial factors for the long lifetime of the BCzDBT devices. [ABSTRACT FROM AUTHOR]

There is an increasing interest in the use of cultivated microalgae to simultaneously produce biodiesel and remove nutrients from various wastewaters. For this purpose, Tetraselmis suecica was cultivated in flasks and fermenters using diluted food-waste recycling wastewater (FRW). The effect of FRW dilution on T. suecica growth and nutrient removal was initially tested in flasks. The maximal microalgal concentration after 14 days was in medium with a twofold dilution (28.3 × 10 cells/mL) and a fivefold dilution (25.5 × 10 cells/mL). When fivefold diluted medium was used in fermenters, the final dry cell weight of T. suecica was 2.0 g/L. The removal efficiencies of ammonium and phosphate in the fermenters were 99.0 and 52.3 %, respectively. In comparison with the results of previous studies, the growth data of T. suecica in the FRW medium indicate that microalgal cultivation system incorporating removal of nutrients in FRW is feasible at the field level. [ABSTRACT FROM AUTHOR]

Ionic liquids have many applications, one of which entails their utilization as powerful solvents. In the present study, various experimental conditions of ionic liquid-mediated direct transesterification were investigated in terms of lipid-extracting ionic liquids, catalyst, reaction time, reaction temperature and volume of methanol to achieve effective FAME conversion with wet microalgal feedstock, Nannochloropsis oceanica. With ionic liquid, [Bmim][CFSO], highest fatty acid methyl ester (FAME) yield was shown. Among many experimental parameters, the two most critical factors to enhance FAME conversion were characteristic of ionic liquids and volume of methanol. Optimized ionic liquid-mediated direct transesterification of wet N. oceanica, compared with a control experiment using chloroform and methanol, increased the FAME conversion yield by 11-fold. [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]

Microalgae hold great promise as a source of biofuels and biochemicals. The main obstacles to their industrial application are the high cultivation and downstream costs related to media and harvesting. In the work, we explored the multiple potentials of seawater to address key issues relating to the cultivation of Scenedesmus obliquus. Seawater can sufficiently replace some of the key elements in BG11 medium such as MgSO, CaCl, and NaCO, and its use can significantly reduce the quantity of water required for the preparation of culture media. Among our results, the total chlorophyll content in cells grown in modified BG11 using 10 % (v/v) seawater was increased 1.47-fold without sacrificing biomass or lipid production. More than 70 % of the total algal biomass was auto-flocculated within one hour when cells were grown in seawater-supplemented media, which compares very favorably with a yield of only 3 % from cells grown in BG11. [ABSTRACT FROM AUTHOR]

A cost-efficient process devoid of several washing steps was developed, which is related to direct cultivation following the decomposition of the sterilizer. Peracetic acid (PAA) is known to be an efficient antimicrobial agent due to its high oxidizing potential. Sterilization by 2 mM PAA demands at least 1 h incubation time for an effective disinfection. Direct degradation of PAA was demonstrated by utilizing components in conventional algal medium. Consequently, ferric ion and pH buffer (HEPES) showed a synergetic effect for the decomposition of PAA within 6 h. On the contrary, NaNO, one of the main components in algal media, inhibits the decomposition of PAA. The improved growth of Chlorella vulgaris and Synechocystis PCC6803 was observed in the prepared BG11 by decomposition of PAA. This process involving sterilization and decomposition of PAA should help cost-efficient management of photobioreactors in a large scale for the production of value-added products and biofuels from microalgal biomass. [ABSTRACT FROM AUTHOR]

The use of wastewater has been investigated to overcome the economic challenge involved with a production of microalgae-based biodiesel. In this study, to achieve economical biodiesel production along with effective wastewater treatment at the same time, anaerobically treated brewery wastewater (ABWW) was utilized as a low-cost nutrient source, in the cultivation of Chlorella protothecoides. About 96 and 90 % of total nitrogen and phosphorus in ABWW were removed, respectively, while C. protothecoides was accumulating 1.88 g L of biomass. The C. protothecoides grown in ABWW showed increases in cell size and cell aggregation, resulting in a near 80 % enhanced harvesting efficiency within 20 min, as compared with only 4 % in BG-11. In addition, the total fatty acid content of the C. protothecoides grown in ABWW increased by 1.84-fold (35.94 ± 1.54 % of its dry cell weight), relative to that of BG-11. [ABSTRACT FROM AUTHOR]

Calcium ion and trace metals play important roles in various metabolisms of photosynthetic organisms. In this study, simple methods were developed to extract calcium ion and micronutrients from oyster shell and common soil, and the prepared extracts were tested as a replacement of the corresponding chemicals that are essential for growth of microalgae. The oyster shell and soil were treated with 0.1 M sodium hydroxide or with 10 % hydrogen peroxide, respectively. The potential application of these natural sources to cultivation was investigated with Spirulina maxima. When compared to standard Zarrouk medium, the Spirulina maxima cultivated in a modified Zarrouk media with elements from oyster shell and soil extract exhibited increases in biomass, chlorophyll, and phycocyanin by 17, 16, and 64 %, respectively. These results indicate that the extracts of oyster shell and soil provide sufficient amounts of calcium and trace metals for successful cultivation of Spirulina maxima. [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]

In this study, lipid extraction from Aurantiochytrium sp. was performed using a molten-salt/ionic-liquid mixture. The total fatty acid content of Aurantiochytrium sp. was 478.8 mg/g cell, from which 145 mg/g cell (30.3 % of total fatty acids) of docosahexaenoic acid (DHA) was obtained. FeCl·6HO showed a high lipid extraction yield (207.9 mg/g cell), when compared with that of [Emim]OAc, which was only 118.1 mg/g cell; notably however, when FeCl·6HO was mixed with [Emim]OAc (5:1, w/w), the yield was increased to 478.6 mg/g cell. When lipid was extracted by the FeCl·6HO/[Emim]OAc mixture at a 5:1 (w/w) blending ratio under 90 °C, 30 min reaction conditions, the fatty acid content of the extracted lipid was a high purity 997.7 mg/g lipid, with most of the DHA having been extracted (30.2 % of total fatty acids). Overall, lipid extraction from Aurantiochytrium sp. was enhanced by the synergistic effects of the molten-salt/ionic-liquid mixture with different ions. [ABSTRACT FROM AUTHOR]

Advances in harvesting of microalgae are needed for the efficient and economical production of microalgal biodiesel. In addition to improvements in recovery efficiency, developments in harvest technology should focus on reducing the adverse impact of subsequent processes, and should also allow water recycling. We investigated a continuous electrochemical approach for microalgal biodiesel production. Instead of conventional DC, pulsed DC was applied as a method of polarity exchange and its performance was analyzed in terms of recovery efficiency, electricity consumption, and residual Al concentration. Under optimized pulsed-DC conditions, 32 % less electricity was required and 7 % less Al was remained after continuous harvesting and there was no decrease in recovery efficiency compared to the continuous harvesting by conventional DC. We also examined the effect of this new protocol on biodiesel quality and water reusability. There were no differences in the microalgal oil composition before and after electrolytic harvesting. In addition, the harvested oil quality, based on four key parameters, was superior to that produced by other terrestrial crops. Lastly, there was no retardation of growth in recycled medium relative to that in fresh medium. [ABSTRACT FROM AUTHOR]

Microalgae-derived biomass has been considered as the most promising candidate for next generation biofuel due to its sustainability and biodegradability. In this study, microalgal strain Chlamydmonas reinhardtii was randomly mutagenized by using a chemical mutagen, ethyl methane sulfonate (EMS) to create mutants showing enhanced lipid production. We identified three random mutants that displayed high lipid production in the screening using Nile red staining. Among those, mutant #128 was selected as candidate for further studies. Our flow cytometry and confocal microscopy analysis revealed that mutant #128 contains larger and more abundant lipid bodies than that of wild-type. Moreover, mutant #128 showed 1.4-fold increased fatty acid methyl ester (FAME) content compared to wild-type under nitrogen depleted condition. In addition, mutant #128 grew faster and accumulated more biomass, resulting in high lipid production. 2D gel electrophoresis and MALDI-TOF analysis used for gene targeting revealed that β-subunit of mitochondrial ATP Synthase and two-component response regulator PilR may be involved in enhanced characteristics of mutant #128. These results show the possibilities of EMS mediated random mutagenesis in generation of mutants to produce high amount of lipid as well as further study for molecular mechanism of mutants. [ABSTRACT FROM AUTHOR]

Ability to increase the lipid production in microalgae is one of the heavily sought-after ideas to improve the economic feasibility of microalgae-derived transportation fuels for commercial applications. We used the oxidative stress by TiO nanoparticles, a well-known photocatalyst, to induce lipid production in microalgae. Chlorella vulgaris UTEX 265 was cultivated under various concentrations of TiO ranging from 0.1 to 5 g/L under UV-A illumination. Maximum specific growth rate was affected in responding to TiO concentrations. In the presence of UV-A, chlorophyll concentration was decreased at the highest concentration of TiO (5 g/L TiO) by oxidative stress. The fatty acid ethyl ester (FAME) composition analysis suggested that oxidative stress causes the accumulation and decomposition of lipids. The highest FAME productivity was 18.2 g/L/d under low concentrations of TiO (0.1 g/L) and a short induction time (two days). The controlled condition of TiO/UV-A inducing oxidative stress (0.1 g/L TiO and two days induction) could be used to increase the lipid productivity of C. vulgaris UTEX 265. Our results show the possibility of modulating the lipid induction process through oxidative stress with TiO/UV-A. [ABSTRACT FROM AUTHOR]

Phycocyanin is a highly valuable pigmented protein synthesized by several species of cyanobacteria and red alga. In this study we demonstrate the production of thermostable phycocyanin from the unicellular red alga Galdieria sulphuraria. Phycocyanin was extracted by repeated freeze-thaw cycles and purified in a two-step process using ammonium sulfate fractionation, at 25% and 50% concentrations. Purified phycocyanin exhibited maximum absorbance at 620 nm, and the purity ratio (A/A) was found to be greater than 4. The recovery efficiency of phycocyanin from the crude extract was above 80%. In total, approximately 19 milligram pure phycocyanin was obtained from 3 g of wet cell mass of Galdieria sp. Subunits α and β of the protein were separated by SDS-PAGE and analyzed by MALDITOF mass spectrometry for identification, which confirmed that the isolated protein is phycocyanin. The molecular weight of α and β subunits of phycocyanin was found to be 17.6 and 18.4 kDa, respectively. [ABSTRACT FROM AUTHOR]

An acidogenic reactor with a 0.5-L working volume and a methanogenic digester with a 5-L of working volume were operated for 150 days on a continuous mode to investigate the structure of a microbial community during food wastewater treatment. During the steady state of anaerobic digestion, volatile solids (VS) removal efficiency in the pilot plant was approximately 65%. The bacterial population was higher than any other methanogens detected during the entire anaerobic process and treatment of raw food wastewater. Methanomicrobiales (MMB), Methanosarcinales (MSL), and Methanobacteriales (MBT) were detected during digestion. The methanogenic population present in the acidogenic reactor was directly affected by the archaeal community in raw food wastewater. However, the shift of microbial community in the methanogenic digester was relatively gradual. The performance of methanogenic digester might be more related to the change of microbial metabolism affected by the physicochemical properties of the input substrate. [ABSTRACT FROM AUTHOR]

This study examined the use of Chlorella vulgaris for the simultaneous bioremediation of municipal wastewater and production of biodiesel. We tested the effect of wastewater dilution on C. vulgaris growth in filtered and sterilized wastewater, sterilized wastewater, and untreated wastewater. Growth was the greatest in untreated wastewater, suggesting that certain wastewater components, such as bacteria, may promote microalgal growth. We confirmed the presence of beneficial bacteria by denaturing gradient gel electrophoresis analysis and inoculation of wastewater bacteria into microalgal cultures in artificial medium. Furthermore, we employed a semi-continuous cultivation process that successfully combined the advantages of indigenous bacteria with a high level of inoculum. Finally, cells grown in wastewater contained high levels of useful fatty acids. Collectively, our data suggest that it may be feasible to use wastewater-grown C. vulgaris biomass for simultaneous bioremediation and biodiesel production. [ABSTRACT FROM AUTHOR]

Microalgal cultivation has been limited by the efficiency and costs associated with providing light energy, the most expensive and essential element needed for microalgal growth to a culture, particularly to cultures grown in a photo bioreactor (PBR). This study examined the economic benefits of using flashing illumination conditions in the context of microalgal cultivation. Chlamydomonas reinhardtii was cultivated under various conditions, including various inoculum sizes, light intensities, and durations of the light and dark periods. Our results showed that the highest microalgal growth efficiencies could be obtained using a large inoculum size under high intensity illumination accompanied by a 1:1 ratio of light and dark periods. The duration of the flashing light period was further optimized; permitting light energy savings of 62.5% of the light energy expended under continuous illumination conditions without reducing the biomass or lipid productivity. This study provides a more economical approach to cultivating C. reinhardtii via optimized flashing illumination without sacrificing microalgal growth or lipid content. [ABSTRACT FROM AUTHOR]

Cultivation is the most expensive step in the production of biodiesel from microalgae, and substantial research has been devoted to developing more cost-effective cultivation methods. Plant hormones (phytohormones) are chemical messengers that regulate various aspects of growth and development and are typically active at very low concentrations. In this study, we investigated the effect of different phytohormones on microalgal growth and biodiesel production in Chlamydomonas reinhardtii and their potential to lower the overall cost of commercial biofuel production. The results indicated that all five of the tested phytohormones (indole-3-acetic acid, gibberellic acid, kinetin, 1-triacontanol, and abscisic acid) promoted microalgal growth. In particular, hormone treatment increased biomass production by 54 to 69 % relative to the control growth medium (Tris-acetate-phosphate, TAP). Phytohormone treatments also affected microalgal cell morphology but had no effect on the yields of fatty acid methyl esters (FAMEs) as a percent of biomass. We also tested the effect of these phytohormones on microalgal growth in nitrogen-limited media by supplementation in the early stationary phase. Maximum cell densities after addition of phytohormones were higher than in TAP medium, even when the nitrogen source was reduced to 40 % of that in TAP medium. Taken together, our results indicate that phytohormones significantly increased microalgal growth, particularly in nitrogen-limited media, and have potential for use in the development of efficient microalgal cultivation for biofuel production. [ABSTRACT FROM AUTHOR]

This study describes the development of a microfluidic device for the high-throughput screening of culture conditions, such as the optimum sodium acetate concentration for promoting rapid growth and high lipid accumulation of Chlamydomonas reinhardtii. An analysis of the microalgal growth on the microfluidic device revealed an optimum sodium acetate concentration of 5.72 g L −1. The lipid content, determined by the 4,4-Difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza- s-indacene (BODIPY® 505/515) staining method, increased with the sodium acetate concentration. The results were found to be statistically reproducible with respect to cell growth and lipid production. Other nutrient conditions, including the nitrogen and phosphorus concentrations, can also be optimized on the same microfluidic platform. The microfluidic device performance results agreed well with the results obtained from the flask-scale experiments, validating that the culture conditions were scalable. Finally, we, for the first time, established a method for the absolute quantification of the microalgal lipid content in the picoliter culture volumes by comparing the on-chip and off-chip data. In conclusion, we successfully demonstrated the high-throughput screening of sodium acetate concentrations that induced high growth rates and high lipid contents in C. reinhardtii cells on the microfluidic device. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In the present study, we established a genetic system for manipulating the oleaginous heterotrophic microalgae Aurantiochytrium sp. KRS101, using cycloheximide resistance as the selectable marker. The gene encoding ribosomal protein L44 (RPL44) of Aurantiochytrium sp. KRS101 was first identified and characterized. Proline 56 was replaced with glutamine, affording cycloheximide resistance to strains encoding the mutant protein. This resistance served as a novel selection marker. The gene encoding the Δ12-fatty acid desaturase of Mortierella alpina, used as a reporter, was successfully introduced into chromosomal DNA of Aurantiochytrium sp. KRS101 via 18S rDNA-targeted homologous recombination. Enzymatic conversion of oleic acid (C18:1) to linoleic acid (C18:2) was detected in transformants but not in the wild-type strain. [ABSTRACT FROM AUTHOR]

The article presents a study which evaluates the utility of aquaporin-4 antibodies (AQP4-Ab) in patients with neuromyelitis optica spectrum disorders (NMOSD). It notes that the radiological and clinical features of 78 patients with NMOSD and 22 with multiple sclerosis (MS) who were examined with AQP4-Ab by a cell-based assay were assessed. Results show that the mean time interval between symptom onset and development of optic neuritis and myelitis was 39.9 months in neuromyelitis optica (NMO).

Two genes from Zymomonas mobilis that are responsible for ethanol production, pyruvate decarboxylase ( pdc) and alcohol dehydrogenase II ( adhII), were heterologously expressed in the Gram-positive bacterium Streptomyces lividans TK24. An examination of carbon distribution revealed that a significant portion of carbon metabolism was switched from biomass and organic acid biosynthesis to ethanol production upon the expression of pdc and adhII. The recombinant S. lividans TK24 produced ethanol from glucose with a yield of 23.7 % based on the carbohydrate consumed. The recombinant was able to produce ethanol from xylose, l-arabinose, mannose, l-rhamnose, galactose, ribose, and cellobiose with yields of 16.0, 25.6, 21.5, 33.6, 30.6, 14.6, and 33.3 %, respectively. Polymeric substances such as starch and xylan were directly converted to ethanol by the recombinant with ethanol yields of 18.9 and 8.8 %, respectively. The recombinant S. lividans TK24/ Tpet developed in this study is potentially a useful microbial resource for ethanol production from various sources of biomasses, especially microalgae. [ABSTRACT FROM AUTHOR]

The oleaginous microalga Aurantiochytrium sp. KRS101 was cultivated in enzymatic hydrolysates of alkali-pretreated empty palm fruit bunches (EFBs), without prior detoxification process. The maximal levels of lipid and docosahexaenoic acid synthesized were 12.5 and 5.4 g L after cultivation for 36 h. Similar lipid levels were also obtained via simultaneous saccharification and cultivation. The results suggested that EFB is a promising source for production of useful lipids by the microalgal strain. [ABSTRACT FROM AUTHOR]

The synthesis of aminoclays with Mg2+ or Fe3+, placed in metal centers by sol–gel reaction with 3-aminopropyltriethoxysilane (APTES) as a precursor, is demonstrated, producing –(CH2)3NH2 organo-functional pendants which are covalent-bonding onto cationic metals. The protonated amine groups in aqueous solution lead the efficient sedimentation (harvesting) of microalgae biomass within approximately 5 min and 120 min for fresh and marine species, respectively. To our surprise, the aminoclays did not depend on microalgae species or media for microalgae harvesting. In particular, the harvesting efficiency (%) of microalgae was not decreased in a wide pH region. The harvesting mechanism can be explained by the sweep flocculation of microalgae, which is confirmed by measurement of zeta potential of aminoclay in aqueous solution where aminoclay shows a positively charged surface in a wide pH region. In order to reduce the cost of aminoclays and to make the harvesting procedures simple, the membrane process using aminoclay-coated cotton filter is introduced for the treatment of 1 L-scale microalgae stocks. It is successfully performed with three recycles using the same aminoclay-coated cotton filter after removing the harvested microalgae biomass. Conclusively, the aminoclay-based microalgae harvesting systems are a promising means of reducing the cost of downstream processes in microalgae-based biorefinery. [ABSTRACT FROM AUTHOR]

It is common that physicians are faced with patients who have severe steno-occlusion of intracranial arteries in the absence of clinical symptoms. This study is to determine whether a 7T magnetic resonance angiogram (MRA) could provide the improved depiction of microvessels of asymptomatic patients with steno-occlusive middle cerebral artery (MCA) and possible clues for diagnosis of their clinical symptoms. All the patients who were identified as severe MCA steno-occlusions underwent a 7T MRA study. Three of these also underwent conventional angiography (TFCA). The vascular densities around the steno-occlusive MCA and posterior cerebral artery (PCA) branches as control vessels were measured and the difference between the median values of 7T and 3T MRA data was also analyzed. The results of 7T MRA revealed numerous microvessels not visible by conventional MRA. These 7T MRA images were also comparable to those obtained by an invasive conventional angiography (TFCA). The median values of vascular densities observed by 7T MRA were significantly higher than those by 3T MRA (5.28 at 7T vs. 1.45 at 3T for steno-occlusive MCA, p = 0.012, while 3.39 at 7T vs. 3.32 at 3T for normal PCA, p = 0.093). Ultra-high-field 7T MRA is a totally noninvasive angiographic technique that is capable of visualizing microvascular circulation that is usually difficult with conventional MRA. This visualization technique, therefore, could provide an important avenue on the diagnosis of steno-occlusion as well as the search of the roles of the microvessel, especially collaterals, in the preservation of normal blood circulation in patients with asymptomatic MCA steno-occlusion. [ABSTRACT FROM AUTHOR]

Bromate ( ) is the harmful element that could be produced from disinfection of drinking water. In this study, surfactant-modified powdered activated carbon(SM-PAC) was synthesized and used for the removal of bromate ( ) from water. Three cationic surfactants, cetylpyridinium chloride (CPC), hexadecyltrimethyl-ammonium chloride (CTAC), and hexadecyltrimethyl-ammonium bromide (CTAB) were used for modification. The effect of operation parameters, pH, and contact time were obtained. Moreover, adsorption mechanisms on SM-PACs were discussed. Compared with untreated activated carbon, CTAC modified SM-PAC exhibited 3 times higher adsorption capacity. These results indicated that SM-PAC removed effectively and rapidly from water without producing harmful byproducts. [ABSTRACT FROM AUTHOR]

In this study, we determined the effect of TNF-α on hBMSCs proliferation as well as the role of IL-1 receptor-associated kinase 1 (IRAK1) on TNF-α signaling. Western blot analysis revealed that TNF-α treatment increased the phosphorylation of IRAK1 in hBMSCs. The downregulation of IRAK1 inhibited TNF-α-induced NF-κB activation and COX-2 expression. TNF-α treatment increased hBMSCs proliferation in a dose-dependent manner and increased ERK, JNK, and NF-κB activity. U0126, an ERK inhibitor, decreased hBMSCs proliferation and significantly blocked TNF-α -induced hBMSCs proliferation. In cells with IRAK1 or TRADD downregulation, the U0126 treatment inhibited hBMSCs proliferation and significantly suppressed TNF-α-induced hBMSCs proliferation. The downregulation of IRAK1 or TRADD inhibited TNF-α-induced ERK and JNK activation, and hBMSCs proliferation. Inhibition of NF-κB by decoy oligonucleotides reduced the TNF-α-induced hBMSCs proliferation. Immunoprecipitation analysis showed that IRAK1 does not physically interact with TNF receptor 1 (TNFR1) even in the presence of TNF-α. Suppression of IRAK1 binding protein (IRAK1BP1) inhibited TNF-α-induced increase of the proliferation and ERK1 phosphorylation of hBMSCs in the presence of TNF-α. Our data indicate that TNF-α modulates hBMSCs proliferation through ERK signaling pathways, and that IRAK1 plays an important role in TNF-α-induced NF-κB activation in hBMSCs. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Over the past several decades, the pharmacological effects of ginsenosides in Panax ginseng roots have been extensively investigated. Here, we developed a method for producing specific ginsenosides (F1 and F2) with good yields (F1:162 mg/g, F2:305 mg/g) using β-glycosidase purified from Aspergillus niger. In addition, each ginsenoside (at least 25 species) was separated and purified by high performance liquid chromatography (HPLC) using five different types of solvents and different purification steps. In addition, the Rg3:Rh2 mixture (1:1, w/w) was shown to inhibit a specific lung cancer cell line (NCI-H232) in vivo, displaying an anticancer effect at a dose lower than achieved using treatments with single Rg3 or Rh2. This finding suggests that the combination of ginsenosides for targeting anticancer is more effective than the use of a single ginsenoside from ginseng or red ginseng. [ABSTRACT FROM AUTHOR]

We developed a novel one-pot synthetic strategy for preparing monodisperse polyethylene glycol diacrylate (PEGDA) microdroplets via organoclay-assisted interfacial polymerization approach for Escherichia coli encapsulation. Based on the mechanism of spontaneous and rapid polymerization of PEGDA precursor solution with Mg-organoclay, the prepared PEGDA microdroplets have uniform size and fine round shape, with size range of 74-118 µm. The size of microdroplets can be controlled through the changing continuous phase flow rate. Organoclay-assisted polymerization method provides a unique environment to produce non-toxic ways of fabricating microorganism encapsulated microdroplets and to prohibit microdroplets merge during the processes. Furthermore, we successfully carried out to entrap E. coli inside of the PEGDA microdroplets. E. coli expressing a green fluorescent protein shows a good viability inside the PEGDA microdroplets. The in situ microfluidic synthetic method provides a novel approach for the preparation of monodisperse PEGDA microdroplets via a one-pot route. Biotechnol. Bioeng. 2012;109: 289-294. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]