Enhanced biomass production of duckweeds by inoculating a plant growth-promoting bacterium, Acinetobacter calcoaceticus P23, in sterile medium and non-sterile environmental waters.

Duckweed offers the promise of a co-benefit culture combining water purification with biomass production. Acinetobacter calcoaceticus P23 is a plant growth-promoting bacterium isolated from a duckweed, Lemna aequinoctialis. This study quantified its growth-promoting effect on three duckweeds (L. aoukikusa, L. minor, and Spirodela polyrhiza) in sterile Hoagland solution and evaluated its usefulness in duckweed culture under non-sterile conditions. P23 promoted growth of three duckweeds in sterile Hoagland solution at low to high nutrient concentrations (1.25-10 mg NO3-N/L and 0.25-2.0 mg PO4-P/L). It increased the biomass production of L. aequinoctialis 3.8-4.3-fold, of L. minor 2.3-3.3-fold, and of S. polyrhiza 1.4-1.5-fold after 7 days compared with noninoculated controls. P23 also increased the biomass production of L. minor 2.4-fold in pond water and 1.7-fold in secondary effluent of a sewage treatment plant under non-sterile conditions at laboratory-scale experiments. P23 rescued L. minor from growth inhibition caused by microorganisms indigenous to the pond water. The results demonstrate that the use of P23 in duckweed culture can improve the efficiency of duckweed biomass production, and a positive effect of P23 on duckweed-based wastewater treatment can be assumed.

Polyhydroxyalkanoate (PHA) accumulation potential and PHA-accumulating microbial communities in various activated sludge processes of municipal wastewater treatment plants.

AIMS: To clarify the polyhydroxyalkanoate (PHA) accumulation potential and the PHA-accumulating microbial community structure in activated sludge in municipal wastewater treatment plants (WWTPs) and to identify their influential factors. METHODS AND RESULTS: Nine activated sludge samples were collected from municipal WWTPs employing various biological treatment processes. In acetate-fed 24-h batch experiments under aerobic and nitrogen- and phosphorus-limited conditions, polyhydroxybutyrate (PHB) content of activated sludge increased from 0-1·3 wt% to 7·9-24 wt%, with PHB yields of 0·22-0·50 C-mol 3-hydroxybutyrate (C-mol acetate)(-1). Microbial community analyses found that activated sludge samples that accumulated >20 wt% of PHB after 24-h PHA accumulation experiments had >5·0 × 10(8) copies g(-1)-mixed liquor-suspended solid of phaC genes. CONCLUSIONS: Results indicated that (i) activated sludge in municipal WWTPs can accumulate up to approx. 20 wt% of PHA without enrichment processes, (ii) PHA accumulation potential of activated sludge varied depending on the operational conditions (treatment processes) of WWTPs, and (iii) phaC gene number can provide a simple indication of PHA accumulation potential. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to compare the PHA accumulation potential and PHA-accumulating microbial communities in activated sludge of various treatment processes. Our findings may be useful for enhancing the resource recovery potential of wastewater treatment systems.

Selenium recovery from kiln powder of cement manufacturing by chemical leaching and bioreduction.

A novel process by using chemical leaching followed by bacterial reductive precipitation was proposed for selenium recovery from kiln powder as a byproduct of cement manufacturing. The kiln powder at a slurry concentration of 10 w/v% with 0.25 M Na2CO3 at 28°C produced wastewater containing about 30 mg-Se/L selenium. The wastewater was diluted four-fold and adjusted to pH 8.0 as preconditioning for bioreduction. A bacterial strain Pseudomonas stutzeri NT-I, capable of reducing selenate and selenite into insoluble elemental selenium, could recover about 90% selenium from the preconditioned wastewater containing selenium of 5 mg-Se/L when supplemented with lactate or glycerol. The selenium concentrations in the treated wastewater were low around the regulated effluent concentration of 0.1 mg-Se/L in Japan.

Severity of psychiatric and physical problems is associated with lower quality of life in methadone patients in Indonesia.

BACKGROUND AND OBJECTIVES: The goal of methadone maintenance treatment (MMT) is to reduce the harm and to improve patients' quality of life (Qol). However, the Qol is also influenced by other co-occurring disorders. Data regarding the Qol and the co-occurrence of these disorders is lacking in low-middle income countries. We therefore describe the prevalence of physical, psychiatric, and drug abuse co-occurring disorders among MMT patients in Indonesia and determine the association between the severity of the co-occurring disorders and the Qol. METHODS: Data were collected in 112 injection drug abusers (IDUs) attending a MMT program in West Java, Indonesia, using validated questionnaires, medical records and laboratory testing. For comparison, 154 IDUs not enrolled in MMT were recruited by respondent driven sampling. RESULTS: The most frequent co-occurring disorders were hepatitis C (92%), HIV (77%), benzodiazepine abuse (56%), and anxiety disorders (32%). IDUs in MMT had one (26%), two (47%), or three (27%) co-occurring disorders. Higher severity in psychiatric and physical problems was associated with poorer Qol. IDUs not enrolled in MMT had similar co-occurring problems. CONCLUSIONS: The prevalence of co-occurring disorders in IDUs in Indonesia is high and they influence their Qol. SCIENTIFIC SIGNIFICANCE: Therefore, comprehensive treatment, especially focusing on the common co-occurring disorders should be provided in MMT to improve the Qol.

A co-beneficial system using aquatic plants: bioethanol production from free-floating aquatic plants used for water purification.

A co-beneficial system using constructed wetlands (CWs) planted with aquatic plants is proposed for bioethanol production and nutrient removal from wastewater. The potential for bioethanol production from aquatic plant biomass was experimentally evaluated. Water hyacinth and water lettuce were selected because of their high growth rates and easy harvestability attributable to their free-floating vegetation form. The alkaline/oxidative pretreatment was selected for improving enzymatic hydrolysis of the aquatic plants. Ethanol was produced with yields of 0.14-0.17 g-ethanol/ g-biomass in a simultaneous saccharification and fermentation mode using a recombinant Escherichia coli strain or a typical yeast strain Saccharomyces cerevisiae. Subsequently, the combined benefits of the CWs planted with the aquatic plants for bioethanol production and nutrient removal were theoretically estimated. For treating domestic wastewater at 1,100 m(3)/d, it was inferred that the anoxic-oxic activated sludge process consumes energy at 3,200 MJ/d, whereas the conventional activated sludge process followed by the CW consumes only 1,800 MJ/d with ethanol production at 115 MJ/d.

Removal characteristics of retinoic acids and 4-oxo-retinoic acids in wastewater by activated sludge treatment.

Retinoic acid (RA) receptor (RAR) agonists are potential teratogens to various vertebrates. Their contamination has been detected in municipal wastewater in different countries. This study involved field investigations and laboratory batch treatment experiments to elucidate the removal characteristics by activated sludge treatment of RAs (all-trans RA and 13-cis RA) and 4-oxo-RAs (4-oxo-all-trans RA and 4-oxo-13-cis RA), which were identified as major RAR agonists in municipal wastewater. Results obtained in this study show that currently employed activated sludge treatments can remove RAs, 4-oxo-RAs and overall RAR agonist contamination effectively from municipal wastewater in general, although high RAR agonistic activity might sometimes remain in the effluent. Laboratory experiments revealed that RAs were removed rapidly from the aqueous phase by adsorption to the sludge, after which they were removed further by biological and/or chemical degradation. Aside from adsorption to the sludge, 4-oxo-RAs were also apparently removed by biological and chemical degradation. Biodegradation contributed greatly to the removal. Results of additional experiments indicated that novel non-identifiable RAR agonists can occur through the biodegradation of 4-oxo-RAs by activated sludge and that they can persist for a long period.

[A man with bulging eyes]. / Een man met uitpuilende ogen.

Graves' orbitopathy may cause multiple symptoms, such as proptosis, redness or inflammation of the conjunctiva, excessive tearing, swelling of the eyelids and pain. Smoking, male gender and old age are significant risk factors for a more severe and active disease.

High risk behavior for HIV transmission among former injecting drug users: a survey from Indonesia.

BACKGROUND: Injecting drug use is an increasingly important cause of HIV transmission in most countries worldwide, especially in eastern Europe, South America, and east and southeast Asia. Among people actively injecting drugs, provision of clean needles and opioid substitution reduce HIV-transmission. However, former injecting drug users (fIDUs) are often overlooked as a high risk group for HIV transmission. We compared HIV risk behavior among current and former injecting drug users (IDUs) in Indonesia, which has a rapidly growing HIV-epidemic largely driven by injecting drug use. METHODS: Current and former IDUs were recruited by respondent driven sampling in an urban setting in Java, and interviewed regarding drug use and HIV risk behavior using the European Addiction Severity Index and the Blood Borne Virus Transmission Questionnaire. Drug use and HIV transmission risk behavior were compared between current IDUs and former IDUs, using the Mann-Whitney and Pearson Chi-square test. RESULTS: Ninety-two out of 210 participants (44%) were self reported former IDUs. Risk behavior related to sex, tattooing or piercing was common among current as well as former IDUs, 13% of former IDUs were still exposed to contaminated injecting equipment. HIV-infection was high among former (66%) and current (60%) IDUs. CONCLUSION: Former IDUs may contribute significantly to the HIV-epidemic in Indonesia, and HIV-prevention should therefore also target this group, addressing sexual and other risk behavior.

Model analysis of energy consumption and greenhouse gas emissions of sewage sludge treatment systems with different processes and scales.

An energy consumption model was developed for evaluating sewage sludge treatment plants (SSTPs) incorporating various treatment processes such as thickening, anaerobic digestion, dewatering, incineration, and melting. Based on data analyses from SSTPs in Osaka, Japan, electricity consumption intensities for thickening, anaerobic digestion, dewatering, incineration, and melting and heat consumption intensities for anaerobic digestion, incineration, and melting were expressed as functions of sludge-loading on each unit process. The model was applied for predicting the energy consumption and greenhouse gas (GHG) emissions of SSTPs using various treatment processes and power and heat generation processes using digestion gas. Results showed that SSTPs lacking incineration and melting processes but having power generation processes showed excess energy production at the high sludge-loading rate. Energy consumption of the SSTPs without incineration and melting processes were low, but their GHG emissions were high because of CH(4) and N(2)O emissions from sludge cake at the landfill site. Incineration and melting processes consume much energy, but have lower CH(4) and N(2)O emissions.

Comparative analysis of DNA-based microbial community composition and substrate utilisation patterns of activated sludge microorganisms from wastewater treatment plants operated under different conditions.

In this study, the microbial community structure and carbon source utilisation profile of activated sludge samples collected from full-scale municipal wastewater treatment plants (WWTPs) operated under different conditions were characterised and compared, respectively, using terminal-restriction fragment length polymorphism (T-RFLP) analysis and Biolog assay. Samples were collected from each biological treatment tank of six conventional activated sludge, two anaerobic-oxic, two anaerobic-anoxic-oxic, and one step-aeration processes in eight full-scale WWTPs in Osaka, Japan. Results of the T-RFLP analysis of eubacterial 16S rDNA showed that microbial communities of activated sludge differed greatly among samples, and that they were affected by process-based operational conditions. In contrast, the carbon source utilisation profiles of activated sludge samples were mutually similar, but appeared to be influenced slightly by aerated conditions at each reaction tank. Similar carbon source utilisation profiles among all samples suggest that the activated sludge community possesses functions that are necessary for wastewater treatment even if the phylogenetic composition is different. Different results from the T-RFLP analysis and Biolog assay suggest that the phylogenetic composition of microbial community might not necessarily reflect the wastewater treatment functions of the activated sludge.

Development of DNA microarray for the evaluation of environmental functions.

DNA microarray mounted 85 functional gene sequences related to carbon, nitrogen and sulphur cycles, chemical degradation, metal metabolisms, and energy flows was developed to evaluate the function and status of the environment. Total of 24 river water samples from 6 sampling stations in 2 rivers in 4 seasons were analyzed using constructed DNA microarray. The numbers and constitution of the functional genes were much affected by the seasonal change. Some of the functional genes related to methane oxidation, nitrite reduction, nitrogen fixation, aromatic compounds degradation (catechol 2,3-dioxygenase), alkane degradation (group I and III) and iron reduction were detected in most of all the samples, suggesting that these could be the general functions of the river environment. Some other functional genes related to ammonium oxidation, aromatic compounds degradation (catechol 1,2-dioxygenase) and alkane degradation (group II) can be a certain indicator for the evaluation of the environmental condition.

Evaluation of biodegradation potential of organic compounds by river water microorganisms.

The aim of this study was to assess the availability of the biodegradation potential of aniline and phenol as the indicator for evaluating pollutant impact on a river environment. Biodegradation tests employing river water microorganisms were carried out by a modified TOC-Handai method using aniline and phenol as substrates. Complete degradation time and half-life were determined as indicators expressing the biodegradation potential of aniline and phenol, respectively. Investigations in Lake Biwa-Yodo River basin for more than two years showed that the biodegradation potential of both compounds varied seasonally. In addition, aniline biodegradation potential seemed to be influenced by the hydraulic retention time at each sampling station, while downstream stations with large input of wastewater from the surrounding cities were divided from upstream stations by phenol biodegradation potential. Comparison of the biodegradation potential in rivers at different pollution levels also showed that polluted and less polluted rivers were clearly divided by phenol biodegradation potential. These results indicated that phenol biodegradation potential can be applied as an indicator for evaluating the soundness of river environment from the view point of ecological function.

Evaluation of effectiveness of chemical and physical sewage treatment technologies for removal of retinoic acid receptor agonistic activity detected in sewage effluent.

Retinoic acid receptor (RAR) is a nuclear receptor involved in vertebrate morphogenesis, growth, cellular differentiation, and tissue homeostasis. Excess expression of the retinoid signaling can cause various developmental toxicities in animals and humans. We previously found that influents from sewage treatment plants (STPs) in Japan had a RAR agonistic activity and the activity cannot be removed completely by conventional biological treatments. In this study, we assessed the performance of chemical and physical sewage treatment technologies-ozonation, ultraviolet treatment, chlorination, coagulation using polyaluminium chloride (PAC) and ferric sulfate, and filtration with ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) membranes-in removal of RAR agonistic activity of STP effluent. All water treatment experiments were conducted in laboratory-scale reactors. The RAR agonistic activity of samples was measured using a yeast two-hybrid assay. Results showed that the effectiveness of tested technologies on the removal of RAR agonistic activity can be ranked as RO or NF > chlorination > ozonation > MF > UV > coagulation with ferric sulfate>>coagulation with PAC. Furthermore, the effectiveness of chlorination might rank lower because excess reaction might bring a side effect by producing some RAR agonistic by-product(s).

Ethanol production from candidate energy crops: water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes L.).

Fermentation modes and microorganisms related to two typical free-floating aquatic plants, water hyacinth and water lettuce, were investigated for their use in ethanol production. Except for arabinose, sugar contents in water lettuce resembled those in water hyacinth leaves. Water lettuce had slightly higher starch contents and lower contents of cellulose and hemicellulose. A traditional strain, Saccharomyces cerevisiae NBRC 2346, produced 14.4 and 14.9 g l(-1) ethanol, respectively, from water hyacinth and water lettuce. Moreover, a recombinant strain, Escherichia coli KO11, produced 16.9 and 16.2 g l(-1) ethanol in the simultaneous saccharification and fermentation mode (SSF), which was more effective than the separated hydrolysis and fermentation mode (SHF). The ethanol yield per unit biomass was comparable to those reported for other agricultural biomasses: 0.14-0.17 g g-dry(-1) for water hyacinth and 0.15-0.16 g g-dry(-1) for water lettuce.

Removal of arsenic from groundwater by arsenite-oxidizing bacteria.

The presence of arsenic in groundwater has been of great public concern because of its high toxicity. For purification of arsenic-contaminated groundwater, bacterial oxidation of arsenite, As(III), with a chemical adsorption process was examined in this study. After As(III) oxidation to arsenate, As(V), arsenic is easily removable from contaminated groundwater because As(V) is more adsorptive to absorbents than As(III). By acclimation to As(III) of high concentrations, a mixed culture of heterotrophic bacteria with high As(III)-oxidizing activity was obtained from a soil sample that was free from contamination. With initial concentration up to 1,500 mg l(-1) As(III), the mixed culture showed high As(III)-oxidizing activity at pH values of 7-10 and at temperatures of 25-35 degrees C. The mixed culture contained several genera of heterotrophic As(III)-oxidizing and arsenic-tolerant bacteria: Haemophilus, Micrococcus, and Bacillus. Activated alumina was added to the basal salt medium containing 75 mg l(-1) As(III) before and after bacterial oxidation. Arsenic removal by activated alumina was greatly enhanced by bacterial oxidation of As(III) to As(V). The isotherms of As(III) and As(V) onto activated alumina verified that bacterial As(III) oxidation is a helpful pretreatment process for the conventional adsorption process for arsenic removal.

Application of real-time polymerase chain reaction (PCR) coupled with ethidium monoazide treatment for selective quantification of viable bacteria in aquatic environment.

Ethidium monoazide (EMA) was used to quantify DNA selectively from viable cells with healthy membrane/cell wall system, but not from dead cells, of a target bacterium in the aquatic environment using real-time PCR. Spiking experiments to determine the EMA treatment conditions showed that EMA treatment with EMA at 10-25 microg/ml and subsequent halogen light exposure for 2 min was suitable for selective quantification of DNA from viable cells in an aquatic sample using real-time PCR coupled with EMA treatment (real-time EMA-PCR). Optimized real-time EMA-PCR was applied in combination with culture-based method and conventional real-time PCR without EMA treatment to elucidate the behavior of an Escherichia coli strain inoculated into a pond water microcosm. Quantification results obtained using real-time EMA-PCR were lower than those by conventional real-time PCR without EMA treatment and higher than those by culture-based method. The results suggest that quantification by real-time EMA-PCR seemed to represent the viable population, which would partly include viable but non-culturable state bacteria. Real-time EMA-PCR optimized here can be a useful tool for selective monitoring of the viable population of a target bacterium in the aquatic environment, and thereby contribute to assessment of potential microbial risks generated from waterborne pathogenic bacteria.

Pint-Sized Public Relations: The Development of Reputation Management.

Until recently, many psychologists were skeptical that young children cared about reputation. New evidence suggests that by age five, children begin to understand the broad importance of reputation and to engage in surprisingly sophisticated impression management. These findings prompt exciting new questions about the development of a fundamental social competency.

Effects of light intensity and water temperature on oxygen release from roots into water lettuce rhizosphere.

The oxygen release rate into the rhizosphere by a floating aquatic plant-water lettuce-was determined under various light intensities (0.0-1.2x10(5)lx) and water temperatures (10-35 degrees C). The net specific oxygen release rate was expressed by a model equation comprising the gross oxygen release rate and the rhizosphere respiration terms. Experimental and simulated results show that the net specific oxygen release rate increased with light intensity up to the optimal value, but slight inhibition by higher light intensities was observed at 10-20 degrees C. With increased water temperature, the respiration rate became larger than the gross oxygen release rate. The maximum net specific oxygen release rate of 11.0-12.5mg-O(2)kg-wet(-1)h(-1) was obtained at the optimal condition of about 25 degrees C and 9.0x10(4)-1.1x10(5)lx. The net oxygen release rate was negligible at 35 degrees C at any light intensity because the respiration rate was much greater than the gross oxygen release rate into the rhizosphere.

Comparative study on chemical pretreatments to accelerate enzymatic hydrolysis of aquatic macrophyte biomass used in water purification processes.

In this study, enzymatic hydrolysis of two floating aquatic plants which are suitable for water purification, water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes L.), was performed to produce sugars. Twenty chemical pretreatments were comparatively examined in order to improve the efficiency of enzymatic hydrolysis. As a result, the alkaline/oxidative (A/O) pretreatment, in which sodium hydroxide and hydrogen peroxide were used, was the most effective pretreatment in terms of improving enzymatic hydrolysis of the leaves of water hyacinth and water lettuce. The amount of reducing sugars in enzymatic hydrolysate of water lettuce leaves was 1.8 times higher than that of water hyacinth leaves, therefore water lettuce seems to be more attractive as a biomass resource than water hyacinth. Although roots of these plants contained large amounts of polysaccharides such as cellulose and hemicellulose, they generated less monosaccharides than from leaves, no matter which chemical pretreatment was tested.

Biodegradation of a variety of bisphenols under aerobic and anaerobic conditions.

There is a group of compounds structurally similar to bisphenol-A (BPA), namely bisphenols (BPs), and some of them are considered to be able to partially replace BPA. In order to assess their biodegradability in the aquatic environment, a variety of BPs; BPA, bis(4-hydroxyphenyl)methane (BPF), bis(4-hydroxyphenyl)ethane (BPE), 2,2-bis(4-hydroxy-phenyl)butane (BPB), 2,2-bis(4- hydroxy-3-methylphenyl)propane (BPP), bis(4-hydroxyphenyl)sulfone (BPS), thiodiphenol (TDP) and 4,4'-dihydroxybenzophenone (HBP); were subjected to biodegradation tests under both aerobic and anaerobic conditions. For the aerobic degradation test, a kind of river-die-away method using several river water samples was used, while pond sediments were used for the anaerobic degradation tests in sealed anoxic bottles. As a whole, the examined BPs could be ranked by their biodegradability under aerobic conditions; BPF, HBP > > BPA > BPP > BPE > BPB > TDP > > BPS. On the other hand, the tendency for the anaerobic biodegradability was; BPF > HBP > BPS, BPA, TDP > BPE > BPB. From the viewpoint of biodegradability, BPF seems to be more environmentally-friendly than BPA and, therefore, may be a candidate to replace BPA for reducing the environmental risks.