Survey of coastal inland pollution sources and their influence on seawater quality in Doam bay,Korea

Inland pollution sources of Doam bay were investigated from August to October in 2013. A total of 210 sources including rivers, streams, domestic, agricultural and industrial discharge points were identified along the coast, including 32 sources that had outflow. Agricultural sources were the largest inland pollution sources (139, 66.2%). Fecal coliform concentrations were measured. These data were combined with water discharge data to determine daily loads of pollutants discharged from each source into the bay. Fecal coliform concentrations were the highest in domestic discharges. However, they only had slight influence because their discharge volume was small. The most significant pollution source was Tamjin River (St.85) due to large amount of discharge volume. The influence of St.85 reached almost half of Doam bay. Fecal coliform levels of streams increased after rainfall, but decreased overtime. Domestic pollution sources were not affected upon rain event.     

Sulfur trioxide formation during oxy-coal combustion

The purpose of this study was to investigate the effects of increased oxygen and carbon dioxide concentration on the formation of sulfur trioxide during oxy-coal combustion in two different types of pilot-scale furnaces: a pulverized-coal and a circulating-fluidized-bed-fired system.For pulverized-coal (PC) testing, concentrations of SO₃ and SO₂ were significantly higher for oxy-fired conditions as compared to air-fired conditions. For a high-sulfur Illinois bituminous coal, SO₃ concentrations were 4–6 times greater on average. When firing a low-sulfur Utah Bituminous coal, SO₃ concentrations were similar for oxy-firing vs. air-firing, and the overall levels were very low compared to the Illinois coal, consistent with differences in the fuel sulfur contents. PC-fired emissions on a normalized mass basis (mass SO₃ per unit energy input) indicated higher SO₃ emissions under air-fired conditions vs. oxy-firing, for both the Illinois and Utah coals.Circulating fluidized bed testing was also carried out using the low-sulfur Utah coal, and SO₃ concentrations were notably higher for oxy-firing vs. air-firing, in contrast to the similar concentration levels observed for PC-firing. When compared on a normalized mass basis, the emissions were similar for both air- and oxy-firing, which is also in contrast to the PC-fired results for this coal.     

Production of valued materials from squid viscera by subcritical water hydrolysis

Subcritical water hydrolysis was carried out to produce valued materials from squid viscera, the waste product of fish processing industries. The reaction temperatures for hydrolysis of rawand deoiled squid viscera were maintained from 180 to 280 degrees C for5 min. The ratio of material to water forhydrolysis was 1:50. Most of the proteins from deoiled squid viscera were recovered at high temperature. The protein yield in raw squid viscera hydrolyzate decreased with the rise of temperature. The reducing sugar yield was higher at high temperature in subcritical water hydrolysis of both raw and deoiled squid viscera. The highest yield of amino acids in raw and deoiled squid viscera hydrolyzates were 233.25 +/- 3.25 and 533.78 +/- 4.13 mg g(-1) at 180 and 280 degrees C, respectively. Most amino acids attained highest yield at the reaction temperature range of 180-220 degrees C and 260-280 degrees C for raw and deoiled samples, respectively. The recovery of amino acids from deoiled squid viscera was about 1.5 times higher than that of raw squid viscera.     

Sequence, biochemical characteristics and expression of a novel Sigma-class of glutathione S-transferase from the intertidal copepod, Tigriopus japonicus with a possible role in antioxidant defense

Glutathione S-transferases (GSTs) play a major role in detoxification of xenobiotics and antioxidant defense. Here we report full-length cDNA sequence of a novel Sigma-class of GST (GST-S) from the intertidal copepod Tigriopus japonicus. The full sequence was of 1,136 bp in length containing an open reading frame (ORF) of 651 bp that encoded 217 amino acid residues. The recombinant Tigriopus GST-S was highly expressed in transformed Escherichia coli. Kinetic properties and effects of pH, temperature and chemical inhibitors on Tigriopus GST-S were also studied. The expression of GST-S was studied using real-time RT-PCR in response to exposure to two oxidative stresses-inducing agents, viz., hydrogen peroxide (H(2)O(2)) and heavy metals (copper, manganese). It was observed that H(2)O(2) (2mM) exposure down-regulated its expression at the initial stage but there was recovery and up-regulation shortly afterwards. In case of heavy metal exposure there was concentration-dependent increase in Tigriopus GST-S gene expression up to 24h. These results suggest that Tigriopus GST-S expression is modulated by prooxidant chemicals and it may play a role against oxidative stress. A majority of other GST isoforms is known to play an important role in antioxidant defense. This study provides a preliminary insight into the possible antioxidant role for Sigma-class of GST in T. japonicus.     

Influence of a soil enzyme on iron-cyanide complex speciation and mineral adsorption

Cyanide is commonly found as ferrocyanide [Fe(II)(CN)(6)](-4) and in the more mobile form, ferricyanide [Fe(III)(CN)(6)](-3) in contaminated soils and sediments. Although soil minerals may influence ferrocyanide speciation, and thus mobility, the possible influence of soil enzymes has not been examined. In a series of experiments conducted under a range of soil-like conditions, laccase, a phenoloxidase enzyme derived from the fungi Trametes versicolor, was found to exert a large influence on iron-cyanide speciation and mobility. In the presence of laccase, up to 93% of ferrocyanide (36-362ppm) was oxidized to ferricyanide within 4h. No significant effect of pH (3.6 and 6.2) or initial ferrocyanide concentration on the extent or rate of oxidation was found and ferrocyanide oxidation did not occur in the absence of laccase. Relative to iron-cyanide-mineral systems without laccase, ferrocyanide adsorption to aluminum hydroxide and montmorillonite decreased in the presence of laccase and was similar to or somewhat greater than that of ferricyanide without laccase. Laccase-catalyzed conversion of ferrocyanide to ferricyanide was extensive though up to 33% of the enzyme was mineral-bound. These results demonstrate that soil enzymes can play a major role in ferrocyanide speciation and mobility. Biotic soil components must be considered as highly effective oxidation catalysts that may alter the mobility of metals and metal complexes in soil. Immobilized enzymes should also be considered for use in soil metal remediation efforts.     

Anaerobic biotransformation of dinitrotoluene isomers by Lactococcus lactis subsp. lactis strain 27 isolated from earthworm intestine

Dinitrotoluenes are widely used as solvents and are intermediates in the synthesis of dyes, explosives, and pesticides. Environmental concerns regarding DNTs have increased due to their widespread use and their discharge into the environment. In this study, the anaerobic biodegradation of four dinitrotoluene isomers, 2,3-, 2,4-, 2,6- and 3,4-DNT, was investigated using Lactococcus lactis subsp. lactis strain 27, which was isolated from the intestines of earthworms. Liquid chromatography/mass spectrometry and NMR spectroscopy showed that L. lactis strain 27 non-specifically reduced the nitro groups on the tested dinitrotoluenes to their corresponding aminonitrotoluenes. L. lactis strain 27, however, did not reduce either sequentially or simultaneously two nitro groups of the dinitrotoluenes, resulting in the formation of the corresponding diaminotoluenes. In vitro formation of dinitroazoxytoluenes suggested the presence of oxygen-sensitive hydroxylaminonitrotoluenes. L. lactis strain 27 was capable of reducing 2,4-, 2,6-, 2,3-, and 3,4-dinitrotoluenes up to 173.6, 66.6, 287.1, and 355 microM, respectively in 12 h incubation. A relatively rapid reduction was observed in the case of the 2,3-, and 3,4-dinitrotoluenes, which have vicinal nitro groups on their arene structure. Non-specific anaerobic reduction of dinitrotoluenes by the intestinal bacterium L. lactis strain 27 differentiated the extent of reduction of DNTs according to the substitutional position of the nitro groups and produced in vitro more toxic dinitroazoxytoluenes, suggesting that anaerobic biotransformation of dinitrotoluenes could increase environmental risk.     

Oviposition-stimulating activity of (E)-capsaicin identified in Capsicum annuum fruit and related compounds towards Helicoverpa assulta (Lepidoptera: Noctuidae)

Summary. The oviposition-stimulating activity of (E)-capsaicin identified in the fruits of red pepper, Capsicum annuum L. (Solanaceae), towards the oriental tobacco budworm, Helicoverpa assulta (Guenée), was examined in the laboratory by using choice and no-choice bioassays. Results were compared with those of the commercially available capsanthin and dihydrocapsaicin, another known constituents of C. annuum fruit, and (Z)-capsaicin. In no-choice oviposition bioassays at 10.5 μg/cm², (E)-capsaicin was the most active oviposition stimulant. Weak stimulatory activity was observed with capsanthin, (Z)-capsaicin and dihydrocapsaicin. In choice oviposition bioassays at 2.6 μg/cm², there were significant differences in oviposition-stimulating activity between (E)-capsaicin and each of the other three alkaloids. Structure-activity relationships indicate that the presence of double bond and its trans configuration appeared to play a crucial role in the oviposition-stimulating activity. On the basis of our results, (E)-capsaicin acts as a contact oviposition stimulant of female H. assulta.     

Outlier detection in phosphorus dry deposition rates measured in South Florida

Dry atmospheric deposition contributes a significant amount of phosphorus to the Everglades of South Florida. Measurement of this deposition is problematic, because samples often are contaminated to varying degrees by bird droppings and other foreign materials. This study attempted to detect and remove the outliers in phosphorus (P) flux rates measured from dry deposition samples. Visual inspection of the samples, recorded in field notes, found that 30.1% of the samples contained animal droppings and frogs. Some of the samples with droppings and frogs (2.3%) had P values greater than 884 μg P m⁻² d⁻¹ (a value twice the standard deviation of the raw data mean), and were removed from further analysis. Outlier detection statistics based on a linear regression were then used for additional data screening. Eight stations in the network of 19 were removed because high contamination precluded the use of the regression model. Of the remaining samples, 15.7% were identified through the regression procedure as contaminated and were removed. The 11 station mean for P dry deposition was 85.8±79.0 μg P m⁻² d⁻¹, prior to the regression analysis, and 74.8±75.1 μg P m⁻² d⁻¹ after removal.     

OUTLIER DETECTION IN TOTAL PHOSPHORUS CONCENTRATION DATA FROM SOUTH FLORIDA RAINFALL1

ABSTRACT: Atmospheric deposition can be a significant source of phosphorus to South Florida's aquatic system. Deposition samples are often contaminated to varying degrees by bird droppings or other foreign materials. This study attempted to use statistical and other methods to detect and remove the outliers in the rain-borne total phosphorus concentration data. Some outliers in the data were identified using field notes derived from visual inspection of the samples. Outlier detection statistics based on a simple linear regression were then used for additional data screening. As a result of these analyses, about 35 percent of the observed values were identified as outlying data which needed to be removed prior to further data analyses. Based on detected outliers in the data from 15 monitoring sites, a lumped cutoff value of 130 4mUg/L was determined. This lumped cutoff value may be useful for further quality control and analyses of the data from the region.