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In this study, Gracilaria verrucosa , which is a red marine macroalgae and potential renewable resource, and methanesulfonic acid (MSA), which is known to be a strong and biodegradable acid catalyst, are introduced to produce levulinic acid (LA), which is a platform chemical, under hydrothermal conversion. Under the optimized conditions of the MSA-catalyzed hydrothermal conversion of G. verrucosa , a 22.02% LA yield based on biomass weight (36.92% based on carbohydrate) was obtained under the conditions of 180 °C, 10% biomass, 0.5 M MSA, and 20 min. In the same conditions, only 0.27% 5-HMF, 1.23% glucose, and 0.47% galactose were obtained. In the relationship of LA yield and combined severity factor (CSF) value, the LA yield was sharply increased to CSF 3.5 and then slightly decreased. Additionally, it fits well with a quadratic polynomial regression model. From these results, the MSA-catalyzed hydrothermal conversion of red-macroalgae G. verrucosa as a potential resource was concluded to be a valuable method for platform chemical production. [ABSTRACT FROM AUTHOR]

In this study, the platform-chemicals and sugar production from the macro-algae, Kappaphycus alvarezii , were investigated. The production of glucose, galactose, levulinic acid (LA), and 5-hydroxymethylfurfural (5-HMF) was evaluated by dilute-acid-catalyzed hydrothermal reaction. By this approach, the respective optimal yields (and reaction conditions) were as follows: glucose 2.15 g/L (reaction temperature: 160 °C, catalyst amount: 1.09%, reaction time: 20 min), galactose 14.47 g/L (160.3 °C, 1.02%, 20.3 min), LA 11.69 g/L (178.2 °C, 2.87%, 39.3 min) and 5-HMF 3.02 g/L (160.6 °C, 1%, 20.1 min). [ABSTRACT FROM AUTHOR]

In this study, a combined process of citric acid-catalyzed pretreatment and enzymatic hydrolysis was applied for production of total reducing sugar (TRS) from marine macro red-algae Gracilaria verrucosa as a potential resource. By citric acid-catalyzed pretreatment under the 1:10 solid-to-liquid ratio, 0.1 M citric acid, 150 °C, 60 min condition, a 50.9% TRS yield was obtained. By subsequent enzymatic hydrolysis using enzyme mixture (20 FBG/g-biomass and 28 FPU/g-biomass), a 57.8% TRS yield was obtained. Because citric acid-catalyzed pretreatment is simple, cheap, and environmentally friendly (do not use hazardous chemicals), these results served to demonstrate the significant potential of citric acid-catalyzed pretreatment to produce TRS for biofuels and biochemicals refinement purposes. [ABSTRACT FROM AUTHOR]

In this study, the hydrolysis of marine macro-algae Gracilaria verrucosa with a solid-acid catalyst was investigated. To optimize the hydrolysis, four reaction factors, including liquid-to-solid ratio, catalyst loading, reaction temperature, and reaction time, were investigated. In the results, the highest total reducing sugar (TRS) yield, 61 g/L (51.9%), was obtained under the following conditions: 1:7.5 solid-to-liquid ratio, 15% (w/v) catalyst loading, 140 °C reaction temperature, and 150 min reaction time. Under these conditions, 10.7 g/L of 5-HMF and 2.5 g/L of levulinic acid (LA) were generated. The application of solid-acid catalyst and marine macro-algae resources shows a very high potential for production of fermentable sugars. [ABSTRACT FROM AUTHOR]

Abstract: Young animals appear much less vulnerable to ischemic insults. In present study, we compared neuronal damage and changes in the immunoreactivities and levels of inflammatory cytokine, interleukin (IL-) 2 as a pro-inflammatory cytokine and its receptor (IL-2Rβ), IL-4 and IL-13 as anti-inflammatory cytokines, in the hippocampal CA1 region between adult and young gerbils after 5min of transient cerebral ischemia. Most (about 89%) of hippocampal CA1 pyramidal neurons showed neuronal damage only in the adult gerbil at 4days post-ischemia; in the young ischemia-group, about 61% of CA1 pyramidal neurons showed neuronal damage at 7days post-ischemia. Thereafter, the neuronal damage in the CA1 pyramidal neurons was not significantly changed in both the groups. IL-2 and IL-2Rβ immunoreactivity in the stratum pyramidale (SP) of the CA1 region was similar in both the sham groups. At 4days post-ischemia, IL-2 and IL-2Rβ immunoreactivity in the adult SP was dramatically decreased; however, in the young SP, they were not changed, and they were decreased at 7days post-ischemia. IL-4 and IL-13 immunoreactivity in the SP of the young sham-group were much lower than those in the adult group. Four days after ischemia-reperfusion, they were dramatically decreased in the adult ischemia-group; however, at this time, they were markedly increased in the young ischemia-group. In brief, our findings indicate that IL-2, 2Rβ, IL-4 and IL-13 immunoreactivity in young gerbils was similar or low compared to those in the adult, and they were decreased at 4days post-ischemia in the adult; however, at this time, they were distinctively increased in the young. [Copyright &y& Elsevier]

Abstract: Neural changes occur in the dam during gestation, and brain size has been shown to decrease across pregnancy in humans as well as rodents. In this study, we monitored neuronal damage, cell proliferation and neuroblast differentiation in the hippocampal dentate gyrus (DG) at age-matched virgin control (17- to 18-week-old), gestation day (GD) 14.5, 16.5 and 18.5 (17- to 18-week-old dams), using NeuN for mature neurons, terminal deoxynucleotidyl dUTP nick-end labeling (TUNEL) and Fluoro-Jade B (F-J B) for neuronal death, Ki67 for cell proliferation and doublecortin (DCX) for neuroblast differentiation in C57BL/6 mice. There were no significant differences in NeuN-immunoreactive (+) neurons between the age-matched control and gestating groups. TUNEL or F-J B positive neurons were rarely detected in the DG in all the groups. Ki67+ cell proliferation was significantly decreased in the subgranular zone of the dentate gyrus (SZDG) at GD16.5. In addition, DCX+ neuroblasts with/without tertiary dendrites were decreased in the SZDG with gestation by GD16.5. However, in the GD18.5 group, the number of Ki67+ nuclei and DCX+ neuroblasts with/without tertiary dendrites was slightly increased compared to that observed at GD16.5. DCX protein levels were low at GD16.5, and thereafter slightly increased. These results suggest that cell proliferation and neuroblast differentiation in DG of the hippocampus is decreased during gestation. [Copyright &y& Elsevier]

Microalgae are renewable, eco-friendly, and sustainable bioresources that have the potential to substitute fuels and chemicals originated fossil resources. The conversion of Chlorella sp. to obtain 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) via thermochemical reaction with a metal-sulfate catalyst (Al 2 (SO 4) 3) is introduced here. The statistical approach is introduced to optimize the conversion conditions. By optimization of the 5-HMF yield, about 23.46% of 5-HMF was obtained under 5% biomass amount and 0.75 g-catalyst/g-biomass at 165 °C and 30 min; the highest LA yield of 32.89% was obtained under 2.5% biomass and 1.0 g-catalyst/g-biomass at 205 °C and 60 min. Furthermore, under such harsh temperature condition and high catalyst amount, the maximum 5-HMF yield of 31.46% was obtained at 0 min, which indicates the time required to attain the set reaction temperature. In the evaluation of the catalytic performance via relationship between combined severity factor and 5-HMF/LA, the yields of 5-HMF and LA were demonstrated to be reasonably satisfied for non-linear sigmoidal equations with high regression. Hence, the application of microalgae and metal-salt catalyst has high potential and accessibility in the production of platform chemicals. • Efficient hydrothermal conversion of C hlorella sp. into 5-HMF and LA by metal sulfate catalyst. • 23.46% 5-HMF was obtained under 5% biomass, 0.75 g-catalyst/g-biomass at 165 °C and 30 min. • 32.89% LA was obtained under 2.5% biomass, 1.0 g-catalyst/g-biomass at 205 °C and 60 min. [ABSTRACT FROM AUTHOR]

Microalgae represent a sustainable feedstock for producing biofuels and biomaterials. In this work, levulinic acid (LA) and formic acid (FA) were produced by catalytic hydrothermal conversion of the lipid-extracted residue of Chlorella vulgaris as a renewable bioresource. Following statistical optimization using a Box–Behnken design, yields of 39.27% LA and 22.06% FA were achieved from 5% biomass treated with 0.95 M HCl at 170 °C for 30 min. In conclusion, lipid-extracted microalgal residue and a Brønsted acid catalyst are useful for producing LA and FA. Simplified diagram of the productions of levulinic and formic acids from lipid-extracted residue of C. vulgaris under optimized condition. ga1 • Lipid-extracted C. vulgaris residue and Brønsted acid catalyst are suitable for producing LA and FA. • 39.2% LA yield obtained under 5% biomass, 0.95 M HCl at 170 °C for 30 min • Yields of LA and FA could be fitted to the non-linear Gaussian equation with CSF. [ABSTRACT FROM AUTHOR]

Microalgae are potential alternative resources that can replace fossil resources for the production of biofuels and chemicals. Levulinic acid (LA) and formic acid (FA) were produced from defatted Scenedesmus obliquus (a green microalga) via sulfuric acid-catalyzed thermochemical conversion using Box-Behnken design. Following optimization, 39.93% LA and 25.82% FA yields were obtained with 5 wt% biomass concentration and 0.8 M H 2 SO 4 as the catalyst at 180 °C for 40 min. Furthermore, LA and FA yields matched well with a non-linear sigmoidal equation with the combined severity factor (CSF). High LA and FA yields were achieved at a CSF > 10.4. The results demonstrated the potential of microalgae as a biomass and Brönsted acid as a catalyst for producing platform chemicals. [ABSTRACT FROM AUTHOR]

• Levulinic acid produced under acid-catalyzed thermochemical conversion. • Lipid-extracted microalgae S. obliquus is available resource for producing LA. • 45.63% LA yield achieved under 5 wt% biomass, 0.85 M HCl at 180 °C for 10 min. • Lipid-extracted microalgae has potential for production of platform chemicals. • LA yields to CSF properly match a non-linear sigmoidal equation. Scenedesmus obliquus , a green microalga of the class Chlorophyceae, has been used to produce biofuels. However, limited research has been reported on platform chemicals that use microalgae as biomass to replace fossil sources. This paper reports on the investigation of levulinic acid (LA) production from lipid-extracted S. obliquus with an acid-catalyzed thermochemical conversion using a statistical experimental approach. For the reaction factors, the highest effect on LA yield resulted from catalyst concentration. The optimized LA yield of 45.63 wt% (70.7 mol%) was achieved with 5 wt% lipid-extracted microalgae and reaction factors of 0.85 M HCl as a catalyst at 180 °C for 10 min. Also, the LA yield as a function of the combined severity factor followed a sigmoid curve. High LA yield resulted from combined severity factors greater than 3.4. These results indicate that the production of platform chemicals may be possible using microalgae feedstocks and thermochemical conversion. [ABSTRACT FROM AUTHOR]

Glucosamine is a monomer of chitin/chitosan, which is a renewable aquatic resource and the second most abundant biopolymer on the Earth. Moreover, methanesulfonic acid (MSA) is known as an eco-friendly green catalyst. In this study, the MSA-catalyzed conversion of glucosamine to levulinic (LA) and formic (FA) acids was optimized using the Box-Behnken statistical approach. The optimal conditions for LA yield were 50 g/L glucosamine, 0.5 M MSA, 200 °C and 30 min, which yielded 49.9% LA and 50.8% FA. The LA yield increased linearly with increasing combined severity factor (CSF) until 3.5 and then, was maintained as the CSF value was further increased. The FA yield behaved similarly to LA. Both trends fitted well to a sigmoid regression model with a high regression value. These results highlight the potential of glucosamine for biofuel and chemicals production via an MSA-catalyzed conversion system. [ABSTRACT FROM AUTHOR]

In utero exposure to lead is known to cause various adverse health outcomes and early life obesity can affect permanent metabolic alterations leading to adverse health outcomes. To examine the relation between perinatal lead exposure and childhood obesity, lead level in cord bloods and growth- and obesity-related markers at birth were measured from 280 mother-child pairs. The weight, height, and body mass index (BMI) of children were measured at birth and followed up several times up to 27 months of age. The relations between lead level and growth- and obesity-related markers were evaluated using a generalized linear model after adjustment for maternal age, maternal BMI, gestational period, cesarean section, and smoking status. The changes of child weight, height, and BMI z-scores at followed-up months of age after birth by lead exposure were evaluated using a generalized linear model after adjustment for covariates used in the analyses for growth- and obesity-related markers and child's gender. The lead level was positively associated with an increase of birth height (p = 0.019) and a decrease of ponderal index at birth (p = 0.027) in boys, but not in girls. Moreover, the lead level was positively associated with increases of BMI z-score after 18 months of age (p = 0.070 at 18 months of age; p = 0.003 at 24 months of age; and p = 0.002 at 27 months of age). Perinatal lead exposure affected accelerated body mass increases at specific times of the children' development. [ABSTRACT FROM AUTHOR]

In this study, the parameters of microalga culture were optimized to maximize the biomass and lipid production of Chlamydomonas hedleyi. Experiments were performed using a two-phase culture system. In the first phase, the nitrate concentration, LED photoperiod, and light intensity were optimized for maximal biomass production. In the second phase, the LED photoperiod and light intensity under nitrate starvation conditions were optimized to induce maximal lipid production. During the first phase of culture, a biomass of 0.95 g DCW/L and the shortest cultivation time were obtained with a nitrate concentration of 240 mg/L, under a 24:0 h light:dark cycle, and a light intensity of 500 µmol m−2 s−1. In the second phase of culture, a maximum lipid content of 41.3% was obtained with a light:dark cycle of 12:12 h and a light intensity of 400 µmol m−2 s−1 under nitrate starvation conditions for 2 days. C. hedleyi lipids meet international biodiesel standards, such as cetane number, iodine value, and oxidative stability. This study contributes to the related literature by providing information on C. hedleyi and evaluating its potential as a biodiesel feedstock. [Display omitted] • Two-phase culture can improve biomass and lipid production of Chlamydomonas hedleyi. • The productivity of C. hedleyi was optimized using light emitting diodes. • Combined stress can induce maximal lipid production in C. hedleyi. • The lipid composition of C. hedleyi meets most international biodiesel standards. [ABSTRACT FROM AUTHOR]

Abstract: Bacterial ghosts generated by the controlled expression of the PhiX174 lysis gene E in Gram-negative bacteria have been known to retain the functional and antigenic determinants of the envelope with their living counterparts and thus represent ideal vaccine candidates. The objective of this study was to examine the potential utility of the PhiX174 E gene driven by the PR/cI regulatory system for the generation of Edwardsiella tarda ghosts. The lysis kinetics in E. tarda were also compared with those in Escherichia coli. Generation of ghosts in the transformants of E. coli and E. tarda carrying plasmid pλPR-cI-Elysis was performed successfully by increasing the incubation temperature up to 42 °C. Compared to E. coli, in which lysis was observed within 30 min and was completed 2 h after induction of E gene expression, onset of E. tarda lysis occurred 2 h after temperature elevation and the lysis process was completed 16 h after induction. At the end of the lysis process, the efficiency of ghost induction in non-lyophilized E. tarda was 99.99±0.01%, as the results of 10 replicate experiments showed. However, no bacterial growth was detected in lyophilized E. tarda. Holes ranging from 80 to 400 nm in diameter were observed in E. tarda ghosts by scanning electron microscopy. The present advance, especially regarding the tight control of ‘E-lysis’ and complete cell killing activity, will provide a new opportunity to improve the efficiency of vaccination against edwardsiellosis. [Copyright &y& Elsevier]

The ability of different phosphorylation modulators to modify the opsonized zymosan (OZ)- and phorbol myristate acetate (PMA)-stimulated respiratory burst activity of rock bream (Oplegnathus fasciatus) head-kidney phagocytes was investigated. OZ-stimulated respiratory burst was significantly inhibited by 5 nM of staurosporine, a protein kinase C (PKC) inhibitor, and completely inhibited by 10 nM of staurosporine, whereas PMA-stimulated respiratory burst was completely inhibited by both 5 and 10 nM of staurosporine. Although genistein, a protein tyrosine kinase (PTK) inhibitor, inhibited significantly both OZ- and PMA-stimulated respiratory burst, OZ-stimulated respiratory burst was inhibited much more selectively than PMA-stimulated one. OZ- and PMA-stimulated respiratory burst were increased significantly by sodium orthovanadate, a protein tyrosine phosphatase inhibitor, and the increased rate of OZ-stimulated respiratory burst was markedly higher than that of PMA-stimulated one. These results suggest that OZ-stimulated respiratory burst is more dependent on PTK while the PMA-stimulated one is more dependent on PKC, and the balance between tyrosine kinase and phosphotyrosine phosphatase activity is important in determining the intensity of respiratory burst in phagocytes. [Copyright &y& Elsevier]

The agro-industrial byproducts from the industries for the Sikhye, traditional Korean food production (AIB-I), the apple juice production (AIB-II), and the soy sauce production (AIB-III) were examined as the substrate for the production of the heteropolysaccharide (PS-7) by B. indica HS2001. Major components of AIB-I are dextrin, maltotriose, and maltose. Major ones of AIB-II and AIB-II were carbohydrate and protein, respectively. Dextrin and AIB-II were found to be better carbon sources than glucose for the production of PS-7. Conversion rates of PS-7s from 2% (w/v) dextrin and 2% (w/v) AIB-II as the carbon source were 20%. As concentration of agro-industrial byproducts as the carbon source increased, cell growth and the production of PS-7 increased whereas conversion rates of PS-7s decreased. The monomeric components of PS-7s produced by B. indica HS2001 with agro-industrial byproducts as the carbon source were identified to be glucose and rhamnose and their molar ratios of rhamnose to glucose were all in the range of 1.0 to 4.5∼4.7. It seems that B. indica HS2001 utilized all the agro-industrial byproducts used in this study and produced PS-7s with the same composition as well as the same molar ratio of their monomeric component. [Copyright &y& Elsevier]

• The highest monosaccharide of G. verrucosa was carried out by a R o of 0.47. • The addition of Tween 20 with CTec2 increased the affinity of G. verrucosa with low K m. • A ΔGLK1:ΔMIG1 : ΔMIG2 : TEF2p:PGM2 strain produced 24.8 g/L ethanol (Y EtOH = 0.46). • The adaptation to high concentration of galactose strain produced 24.8 g/L ethanol. • The galactose uptake rate of adapted strain was higher than the engineered strain. Gracilaria verrucosa can be used as a biomass source for bioethanol production with a high yield due to the high carbohydrate content. A monosaccharide concentration of 48.6 g/L was obtained from G. verrucosa using 0.2 M HNO 3 at 150 °C for 10 min with a combined severity factor (R o) of 0.47. The addition of Tween 20 with CTec2 increased the affinity of G. verrucosa slurry to the enzyme with a K m value of 1.14 g/L compared with the K m value of 1.82 g/L using CTec2 alone and reduced enzyme loading. To improve galactose consumption, the deletion of repressor genes including GLK1 , MIG1 , and MIG2 and the overexpression of PGM2 were investigated. The strain with the deletion of three repressor genes and overexpression of PGM2 produced 24.8 g/L ethanol (Y EtOH = 0.46) and showed an enhanced galactose consumption rate (0.24 g/L/h) compared with the rate of the control strain (0.04 g/L/h). The deletion of three repressor genes and overexpression of PGM2 reduced the repression of GAL genes and increased the transcription level of GAL genes. However, the galactose consumption rate of this strain was lower than that of the strain adapted to a high concentration of galactose. [ABSTRACT FROM AUTHOR]

• G. amansii contains 53 μg/g R-phycoerythrin and 56 μg/g R-phycocyanin. • A maximum monosaccharide production of 45.4 g/L (70.7%) was achieved after pretreatment and saccharification of G. amansii. • Fermentation at pH 6.0 supported a high cell growth rate and both glucose and galactose consumption. • The maximum ABE concentration reached 15.5 g/L when pH was shifted from 6.0–4.5. The red seaweed, Gelidium amansii , contains proteins such as R-phycoerythrin and R-phycocyanin, as well as polysaccharides. Initial protein extraction from G. amansii yielded 53 μg/g R-phycoerythrin and 56 μg/g R-phycocyanin. After protein extraction, monosaccharides were produced using hyper thermal acid hydrolysis and enzymatic saccharification. Acetone–butanol–ethanol (ABE) was produced by Clostridium acetobutylicum KCTC 1790. To overcome the different pH requirements for monosaccharide consumption and solvent production, a two-stage pH control culture strategy was developed. Fermentation at pH 6.0 supported a high cell growth rate and both glucose and galactose were consumed completely. The pH was then shifted from 6.0 to 4.5 to produce ABE after 84 h. The maximum ABE concentration reached 15.5 g/L in comparison to 3.1 g/L under fermentation without pH control. The two-stage pH control strategy is a suitable method for ABE production from G. amansii. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Nitrate depletion, salt, and LED wavelengths of second-phase were used for stresses. • Green LED wavelength stress induced the production of microalgal lipid. • The three microalgae, P. tricornutum have high nitrate uptake for cell growth. • The synthesis of fatty acids in microalgae led to form UFAs by stresses. Abstract The effects of wavelengths of light-emitting diode (LED), nitrate concentration, and salt concentration were evaluated for the two-phase culture of the microalgal species Phaeodactylum tricornutum , Dunaliella tertiolecta , and Isochrysis galbana on cell growth and lipid production. Blue LEDs produced the highest biomass of P. tricornutum at a nitrate concentration of 8 mg/L, reaching 0.97 g dcw/L with a specific growth rate (μ) of 0.047 h−1, followed by I. galbana with 0.79 g dcw/L and μ = 0.040 h−1 and D. tertiolecta with 0.55 g dcw/L and μ = 0.028 h−1. Of the three microalgae, P. tricornutum had the highest specific growth rate of μ max = 0.070 h−1 and lowest saturation constant of K s = 4.18 mg/L, resulting in fast cell growth. The highest lipid production was obtained under green LED wavelength stress on day 14, reaching 60.6% (w/w) of the dry cell weight among the three microalgae. The main fatty acids produced by the three microalgae were myristic acid (C14:0), palmitic acid (C16:0), oleic acid (C18:1), and arachidic acid (C20:0), which comprised 72.68%–84.16% (w/w) of the total fatty acids content under three stresses. [ABSTRACT FROM AUTHOR]

Highlights • N. oceanica was cultured in 14-L photobioreactors using a three-phase culture system. • Maximum biomass was produced with 24 h blue LED light at an intensity of 250 µmol m−2 s−1. • Maximum lipid content was obtained with 24 h green LED light at an intensity of 250 µmol m−2 s−1. • SFAs were changed to MUFAs and PUFAs at low temperatures (15, 10, and 5 °C). • The highest PUFA content was obtained at a culture temperature of 5 °C. Abstract A three-phase culture system combining blue (465 nm) light-emitting diode (LED) wavelength as the first phase, green (550 nm) as the second phase, and temperature stress as the third phase was applied to a Nannochloropsis oceanica culture in 14-L photobioreactors. Microalgal growth promotion parameters were optimized in the first phase, followed by green LED stress for lipid production in the second phase. Maximum biomass and lipid production values of 0.75 gdcw L−1 and 57.6% (w/w) were obtained at an aeration rate of 0.50 vvm, with a light intensity of 250 µmol m−2 s−1 and 24:0 h light/dark cycle. Culture temperatures of 15, 10 and 5 °C were applied in the third phase, where temperature stress induced the production of monounsaturated and polyunsaturated fatty acid synthesis in N. oceanica. The production of α-linolenic acid, eicosapentaenoic acid and docosahexaenoic acid increased by 52% (w/w), 96% (w/w), and 77% (w/w), respectively, at 5 °C in the third phase. [ABSTRACT FROM AUTHOR]

Several studies suggested potential links of phthalates to stress-related outcomes. However, limited evidence has been available for the relationships between phthalate metabolites and free cortisol and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in perinatal and postnatal environments. Therefore, we evaluated the relationships between phthalate metabolites and free cortisol and 8-OHdG in mother–child pairs. We repeatedly collected urine samples of 287 mother–child pairs from just before delivery to 15 months of age to measure the levels of four phthalate metabolites – mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono-isobutyl phthalate (MiBP), and mono- n -butyl phthalate (MnBP) – and free cortisol and 8-OHdG. We used linear mixed effect models and generalized additive mixed models to estimate the relationship between the phthalate metabolites and free cortisol and 8-OHdG after adjusting for the child's gender, urine collection time, and maternal smoking status. The four phthalate metabolite levels were strongly correlated each other (all, p  < .0001), and intra-class correlation for each metabolite in children ranged from 0.18 to 0.96. All four phthalate metabolites were positively associated with both free cortisol (MEHHP, β = 0.18 and p  < .0001; MEOHP, β = 0.17 and p  < .0001; MiBP, β = 0.13 and p  = .0001; MnBP, β = 0.21 and p  < .0001; and molar sum of metabolites, β = 0.21 and p  < .0001) and 8-OHdG (MEHHP, β = 0.20 and p  < .0001; MEOHP, β = 0.18 and p  < .0001; MiBP, β = 0.23 and p  < .0001; MnBP, β = 0.28 and p  < .0001; and molar sum of metabolites, β = 0.29 and p  < .0001) in childhood. Our findings suggest that phthalate exposures increase free cortisol and 8-OHdG levels in early childhood. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) exposure during the perinatal and postnatal periods increases the susceptibility to disease over the life cycle. However, information on the BPA delivered to fetuses or infants via the placenta and breastfeeding is limited. We determined the BPA exposure levels in various bodily fluids and tissues of pregnant women and described fetus and infant exposures to BPA based on associations and BPA ratios in mother–neonate paired samples. Maternal serum, urine, placenta, breast milk, cord serum, and neonatal urine samples were collected from 318 mother–neonate pairs at six university hospitals in Korea. BPA levels were detected using liquid chromatography tandem mass spectrometry. The ratios of the BPA levels in the other sample types to the levels in maternal serum were calculated. BPA was detected in 79.5–100% of the maternal and fetal samples. The median BPA concentration in the samples decreased in the order of neonatal urine (4.75 ng/mL), maternal urine (2.86 ng/mL), cord serum (1.71 ng/mL), maternal serum (1.56 ng/mL), breast milk (0.74 ng/mL), and the placenta (0.53 ng/g). We estimated the ratios of BPA levels in the other sample types to those in maternal serum. The median (95th percentile) cord serum-to-maternal serum ratio was 1.12 (15.2) for 160 mother–fetal pairs, in which BPA was detected in both samples. The placenta-, maternal urine-, neonatal urine-, and breast milk-to-maternal serum ratios were 0.28 (5.31), 1.79 (29.9), 1.98 (28.2), and 0.51 (10.5), respectively. In addition, the median (95th percentile) cord serum-to-placenta ratio was 4.03 (45.8), and the neonatal urine-to-cord serum ratio was 1.95 (25.6). The 95th percentile values were 14–20-fold greater than the medians. Urine contained the highest BPA concentrations, followed by serum, breast milk, and the placenta. The variations of BPA ratio show individual differences in the amounts of BPA delivered from mother to fetus. [ABSTRACT FROM AUTHOR]

Exposure of the developing fetus and infants to toxic substances can cause serious lifelong health consequences. Several chemicals have been associated with adverse neurodevelopmental disorders in the early life stages of humans. However, most epidemiological studies have focused on a limited number of chemicals, and hence may exclude important chemicals from consideration or result in conclusions built on associations by chance. In the present study, we investigated the chemical exposure profile of the women, and associated these with the early neurodevelopmental performance of their offspring at 13–24 months of age. The chemicals assessed include four phthalates, bisphenol A, three heavy metals, 19 polychlorinated biphenyls (PCBs), 19 organochlorine pesticides, and 19 polybrominated diphenyl ethers, which were measured from urine, whole blood, serum, and/or breastmilk of the pregnant or lactating women. For neurodevelopmental performance, the Bayley Scales of Infant Development-II (BSID-II), Social Maturity Scale (SMS), and Child Behavior Checklist (CBCL) were measured from a total of 140 toddlers. Among the measured chemicals, monoethyl phthalate (MEP) in maternal urine was significantly associated with early mental, psychomotor, and social development. In addition, breast milk di-ethylhexyl phthalate (DEHP) metabolite and blood lead concentrations were inversely associated with mental and psychomotor development indices, respectively. Maternal blood PCB153, heavy metals, and urinary MEP levels were also higher among the children with behavioral problems, as indicated by the CBCL range. Taken together, maternal exposure to several EDCs such as PCBs and DEHP was associated with adverse neurodevelopmental performances among the children aged 1–2 years. Confirmation of these association in larger populations, as well as longer-term consequences of such exposure warrant further investigation. [ABSTRACT FROM AUTHOR]

Blue and red light-emitting diodes (LEDs) were used to study the effects of wavelength mixing ratios, photoperiod regimes, and green wavelength stress on Nannochloropsis salina , Isochrysis galbana , and Phaeodactylum tricornutum cell biomass and lipid production. The maximum specific growth rates of I . galbana and P . tricornutum were obtained under a 50:50 mixing ratio of blue and red wavelength LEDs; that of N . salina was obtained under red LED. Maximum cell biomass for N . salina and P . tricornutum was 0.75 and 1.07 g dcw/L, respectively, obtained under a 24:0 h light/dark cycle. However, the maximum I . galbana biomass was 0.89 g dcw/L under an 18:6 h light/dark cycle. The maximum lipid contents for N . salina, I . galbana , and P . tricornutum were 49.4, 63.3 and 62.0% (w/w), respectively, after exposure to green LED. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were obtained 1% in P . tricornutum and 2% in I . galbana . [ABSTRACT FROM AUTHOR]

Mercury and lead are naturally occurring toxicants and are responsible for various health issues including neurobehavioral and developmental disorders. Because of crucial synchronized developmental processes occurring at the early stage of life, infancy and childhood are considered as among the most susceptible windows to the exposure to these metals. Breastmilk is often the only source of nutrition during the first months of life. As breastmilk can be contaminated with these metals, breastfeeding may serve as a significant route of heavy metal exposure among infants. In order to understand current levels of exposure to mercury and lead through breastfeeding, and their associated risks, a total of 157 lactating mothers were recruited from Children's Health and Environmental Chemicals of Korea (CHECK) cohort, and breastmilk samples were collected at 15 and 30 days after delivery ( n = 207). Mercury was detected from 100% of breastmilk with a median concentration of 0.59 μg/L, and lead was detected in 77% of the samples with a median at 4.71 μg/L. Higher concentrations of lead were found in the 30- day breastmilk than in the 15-day. Up to 45% of the breastmilk samples exceeded the normal range of the breastmilk lead suggested by WHO. Based on Monte Carlo simulation, about 71% of 15 days old infants and 56% of 30 days old infants were estimated at risk due to lead exposure through breastfeeding. Considering vulnerability of infants and well-known neurological toxicity of these metals, further studies to identify major exposure sources that contribute the lead concentration in breastmilk and health implication of early life stage exposure to lead among the breastfed infants are warranted. [ABSTRACT FROM AUTHOR]

Phthalates are important group of endocrine disruptors. Infants and young children are susceptible to phthalate exposure. However, information on the phthalate exposure during the early stages of life is very limited. This study was conducted to understand the temporal trend of exposure to major phthalates among infants of Korea during the first 15 months after birth, and to estimate associated risks. A total of 286 urine samples were collected from 171 children at 3, 9, 12, or 15 months of age, with 77 children sampled for two or more times. Four phthalates, i.e., di(2-ethylhexyl) phthalate (DEHP), di-isobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and diethyl phthalate (DEP) were chosen, and their major metabolites were analyzed in the urine. The DEHP metabolites were detected in 100% of the urine samples at relatively higher levels compared to those reported in other countries. The levels of mono-ethyl phthalate (MEP) were generally lower. Urinary concentrations of most phthalate metabolites, especially DEHP metabolites, increased as children grew older. Intra-class correlation coefficients (ICCs) calculated for DEHP metabolites over time were high (0.7–0.8), suggesting persistence of consistent exposure sources during this sensitive period of life. Hazard quotient (HQ) and hazard index (HI) were calculated from daily intake estimates divided by recommended toxicity thresholds. Among the study population, 4, 16, and 26% of the children showed HI > 1 at 9, 12, and 15 months of age, respectively. DEHP exposure explained most of the risk estimates. Considering vulnerability of young children to endocrine disruption, efforts to identify sources of exposure and to develop appropriate mitigation options are warranted. [ABSTRACT FROM AUTHOR]

The effects of light-emitting diode (LED) wavelength, light intensity, nitrate concentration, and time of exposure to different LED wavelength stresses in a two-phase culture on lipid production were evaluated in the microalga, Picochlorum atomus . The biomass produced by red LED light was higher than that produced by purple, blue, green, or yellow LED and fluorescent lights from first phase of two-phase culture. The highest lipid production of P. atomus was 50.3% (w/w) with green LED light at 2 days of second phase as light stress. Fatty acid analysis of the microalgae showed that palmitic acid (C16:0) and linolenic acid (C18:3) accounted for 84–88% (w/w) of total fatty acids from P. atomus . The two-phase culture of P. atomus is suitable for biofuel production due to higher lipid productivity and favorable fatty acid composition. [ABSTRACT FROM AUTHOR]

Conditions of light-emitting diode (LED) wavelength, light intensity, nitrate concentration, and time of exposure to green LED light stress in a two-phase culture were optimized for lipid production with three species of microalgae. Among the three microalgae, Nannochloropsis oculata showed the highest specific growth rate ( μ max ) of 0.037 h −1 and the lowest saturation constant ( K s ) of 1.32 mg/L. The highest lipid contents of the three microalgae in the second phase under green LED light stress were 52.0% (w/w) for Nannochloropsis salina at 2 days, 53.0% (w/w) for Nannochloropsis oceanica at 2 days, and 56.0% for N. oculata at 2 days. Fatty acid analysis of the microalgae showed that 85–87% (w/w) of total fatty acids from N. salina , N. oceanica , and N. oculata consisted of palmitic acid (C16:0) and oleic acid (C18:1). [ABSTRACT FROM AUTHOR]

Hyper thermal (HT) acid hydrolysis of Kappaphycus alvarezii , a red seaweed, was optimized to 12% (w/v) seaweed slurry content, 180 mM H 2 SO 4 at 140 °C for 5 min. The maximum monosaccharide concentration of 38.3 g/L and 66.7% conversion from total fermentable monosaccharides of 57.6 g/L with 120 g dw/L K. alvarezii slurry were obtained from HT acid hydrolysis and enzymatic saccharification. HT acid hydrolysis at a severity factor of 0.78 efficiently converted the carbohydrates of seaweed to monosaccharides and produced a low concentration of inhibitory compounds. The levels of ethanol production by separate hydrolysis and fermentation with non-adapted and adapted Kluyveromyces marxianus to high concentration of galactose were 6.1 g/L with ethanol yield ( Y EtOH ) of 0.19 at 84 h and 16.0 g/L with Y EtOH of 0.42 at 72 h, respectively. Development of the HT acid hydrolysis process and adapted yeast could enhance the overall ethanol fermentation yields of K. alvarezii seaweed. [ABSTRACT FROM AUTHOR]

Atomoxetine (ATX) is a non-stimulant selective norepinephrine reuptake inhibitor that is widely used for the treatment of attention-deficit/hyperactivity disorder (ADHD). In this study, we firstly examined neuroprotective effects of pre- or post-treatment with 15 and 30 mg/kg ATX against ischemic damage in the gerbil hippocampal cornus ammonis 1 (CA1) region subjected to 5 min of transient cerebral ischemia using cresyl violet staining, neuronal nuclei immunohistochemistry and Fluoro-J B histofluorescence staining. We found that only pre-treatment with 30 mg/kg ATX protected CA1 pyramidal neurons from ischemic insult. In addition, pre-treatment with 30 mg/kg ATX, which had neuroprotective effect against ischemic damage, distinctly attenuated the activation of astrocytes and microglia in the ischemic CA1 region compared with the vehicle-treated ischemia group by glial fibrillary acidic protein (for astrocytes) and ionized calcium-binding adapter molecule 1 (for microglia) immunohistochemistry. In brief, our present results indicate that ATX has neuroprotective effect against transient cerebral ischemic insult and that the neuroprotective effect of ATX may be closely associated with attenuated glial activation. [ABSTRACT FROM AUTHOR]

A two-stage culture strategy was used for maximum biomass production under nutrient-sufficient conditions, followed by cultivation under low-salt stress, to cause the accumulation of oil in the biomass. Controlled conditions of nitrate, salt concentration, and time to exposure to stress were optimized for oil production with four species of microalgae, Isochrysis galbana , Nannochloropsis oculata , Dunaliella salina , and Dunaliella tertiolecta . Using conditions with addition of nitrate to 24.0 mg/L, I. galbana and N. oculata showed higher biomass productions than D. salina and D. tertiolecta . The oil contents of the microalgae increased from 24.0% to 47.0% in I. galbana with 10 psu for 2 days, from 17.0% to 29.0% in N. oculata with 0 psu for 3 days, from 22.0% to 43.0% of D. salina with 10 psu for 1 day, and from 23.0% to 40.0% (w/w) in D. tertiolecta with 0 psu for 2 days as the second stage culture with low-salt stress. Thus, I. galbana could be a suitable candidate microalga for oil production. [ABSTRACT FROM AUTHOR]

Phthalates have been associated with endocrine disruption and developmental effects in many experimental and epidemiological studies. Developing infants are among the most susceptible populations to endocrine disruption. However, limited information is available on phthalate exposure and its associated risks among breast-fed newborn infants. In the present study, breast milk samples were collected from 62 lactating mothers at 1 month post-partum from four cities of Korea in 2012 and were evaluated for six phthalate metabolites (mono-isobutyl phthalate (MiBP), mono-n-butyl phthalate (MnBP), mono(2-ethyl-hexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and monoethyl phthalate (MEP)). MEP was detected in all breast milk samples, with a median concentration of 0.37 μg/L, and MiBP, MnBP and MEHP were detected in 79–89% of samples, with median concentrations of 1.10, 1.70, and 2.08 μg/L, respectively. However, MEHHP and MEOHP, the oxidized forms of di-ethyl-hexyl phthalate (DEHP), were detected in only one sample. For exposure assessment, the levels of phthalate diesters were estimated based on the parent:metabolite ratios in the breast milk that are reported elsewhere. For risk assessment, the endocrine-related toxicity of the monoester was assumed to be the same as that of its diester form. Median daily intake estimates of phthalates, including both monoester and diester forms, through breast milk consumption ranged between 0.91 and 6.52 μg/kg body weight (bw) for DEHP and between 0.38 and 1.43 μg/kg bw for di-n-butyl phthalate (DnBP). Based on the estimated daily intake, up to 8% of infants exceeded the reference dose of anti-androgenicity (RfD AA) for DEHP, and 6% of infants exceeded the tolerable daily intake (TDI) for DnBP. Breast milk MiBP and MnBP concentrations showed significant positive associations with maternal consumption of whipped cream or purified water. Considering vulnerability of young infants, efforts to mitigate phthalate exposure among lactating women are warranted. [ABSTRACT FROM AUTHOR]

Abstract: Data on the residue levels of persistent organic pollutants (POPs) in baby food samples are scarce. This is the first study to explore current contamination status and exposure assessment of organochlorines (OCs), including polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), in baby food from Korea. In this study, the concentrations of OCs were determined in homemade baby food samples (n =100) collected from 6-, 9-, 12- and 15-month-old infant groups. The average concentrations of PCBs, dichloro-diphenyl-trichloroethanes (DDTs), hexachlorocyclohexanes (HCHs) and chlordanes (CHLs) in baby food samples were 37.5, 96.6, 26.0, and 13.2pg/g fresh weight, respectively. The major compounds were CBs 28, 153, 52, and 33 for PCBs and p,p′-DDE, p,p′-DDT and β-HCH for OCPs. The contribution of DDTs to the total OC concentrations increased from 30% (6-month-old infants) to 67% (15-month-old infants) with increasing infant age, while the concentrations of PCBs, HCHs and CHLs gradually decreased with increasing infant age, suggesting that highest priority for risk reduction of DDTs. The estimated daily intakes (EDIs) of OCs in Korean infants from baby food consumption were lower than the thresholds proposed by the United States Environmental Protection Agency and Health Canada, implying limited potential health risks. However, considering simultaneous exposure from baby food and breast milk consumption, chlordanes and heptachlor epoxide posed potential health risks. Considering the importance of early development and the vulnerability of infants, it is essential to perform systematic monitoring and management programs of OCs in baby food for risk reduction in Korean infants. [Copyright &y& Elsevier]

Abstract: Background: It is not easy to predict the prognosis of patients receiving extracorporeal life support (ECLS) because of the highly variable situation around its implementation. We evaluated the role of pulse pressure (PP), which is available on real-time basis, as a hemodynamic prognostic marker during ECLS. Methods: From January 2009 to August 2011, data from 69 patients who were treated with ECLS for at least 6h in a single center for any cause was collected. We calculated the mean PP over the first 6h after ECLS implantation and examined if there was any correlation between mean PP and the study endpoints, in-hospital death and ECLS weaning failure. Results: The causes of ECLS were of cardiac origin in 36 patients (52%). 27 patients (39.1%) weaned off ELCS and 13 patients (18.8%) survived to discharge. In Cox regression analysis (with age, Killip class ≥3, ECLS implementation during cardiopulmonary resuscitation (CPR), CPR duration, out-of-hospital arrest, initial laboratory results including blood gas analysis, initial systolic blood pressure (SBP), mean SBP over the first 6h after ECLS implantation, mean PP over the first 6h after ECLS implantation as independent variables), mean PP over the first 6h after ECLS implantation (hazard ratio [95% confidence interval]=0.96[0.94–0.98], P <0.001) and out-of-hospital arrest (HR[95%CI]=2.04[1.14–3.62], P =0.02) were independent predictors of in-hospital mortality and mean PP over the first 6h after ECLS implantation (HR[95% CI]=0.95[0.93–0.98], P <0.001) was the sole independent predictor of weaning failure. Conclusion: Higher mean PP over the initial 6h after ECLS implementation independently predicted successful weaning and survival. Our findings may help better predict and analyze prognosis in patients receiving ECLS. [Copyright &y& Elsevier]