Removal of endocrine disruptor compounds, CO2 fixation, and macromolecules accumulation in Thermosynechococcus sp. CL-1 cultivation.

Recently, concern on several environmental issues including the pollutant discharge and high concentration of CO2 have gained high interest due to its impact on ecosystem and global warming effect, respectively. Implementation of photosynthetic microorganism carries out numerous advantages including high efficiency of CO2 fixation, the great endurance under extreme conditions and generation of valuable bioproducts. Thermosynechococcus sp. CL-1 (TCL-1), a cyanobacterium, has the ability to perform CO2 fixation and accumulation of various byproducts under extreme conditions like high temperature and alkalinity, presence of estrogen, or even using swine wastewater. This study aimed to assess TCL-1 performance under various endocrine disruptor compounds (bisphenol-A, 17-ß-estradiol/E2, and 17-α-ethynilestradiol/EE2), concentrations (0-10 mg/L), light intensities (500-2000 µE/m2/s), and dissolved inorganic carbon/DIC levels (0-113.2 mM). Addition of E2 content even until 10 mg/L carried out insignificant biomass growth interruption along with the improvement in CO2 fixation rate (79.8 ± 0.1 mg/L/h). Besides the influence of E2, application of higher DIC level and light intensity also enhanced the CO2 fixation rate and biomass growth. The highest biodegradation of E2 at 71% was achieved by TCL-1 in the end of 12 h cultivation period. TCL-1 dominantly produced protein (46.7% ± 0.2%), however, production of lipid and carbohydrate (39.5 ± 1.5 and 23.3 ± 0.9%, respectively) also could be considered as the potential source for biofuel production. Thus, this study can provide an efficient strategy in simultaneously dealing with environmental issues with side advantage in production of macromolecules.

Toxicity prediction: An application of alternative testing and computational toxicology in contaminated groundwater sites in Taiwan.

Groundwater contamination remains a global threat due to its toxic effects to humans and the environment. The remediation of contaminated groundwater sites can be costly, thus, identifying the priority areas of concern is important to reduce money spent on resources. In this study, we aimed to identify and rank the priority groundwater sites in a contaminated petrochemical district by combining alternative, non-animal approaches - chemical analysis, cell-based high throughput screening (HTS), and Toxicological Priority Index (ToxPi) computational toxicology tool. Groundwater samples collected from ten different sites in a contaminated district showed pollutant levels below the detection limit, however, hepatotoxic bioactivity was demonstrated in human hepatoma HepaRG cells. Integrating the pollutants information (i.e., pollutant characteristics and concentration data) with the bioactivity data of the groundwater samples, an evidence-based ranking of the groundwater sites for future remediation was established using ToxPi analysis. The currently presented combinatorial approach of screening groundwater sites for remediation purposes can further be refined by including relevant parameters, which can boost the utility of this approach for groundwater screening and future remediation.

CO2 fixation and cultivation of Thermosynechococcus sp. CL-1 for the production of phycocyanin.

Cultivation of Cyanobacteria is preferable for CO2 fixation process due to its efficiency and production of beneficial byproducts like phycocyanin. In this study, Thermosynechococcus sp. CL-1 (TCL-1) was cultivated in a 30 L flat panel photobioreactor using a 3-fold-modified Fitzgerald medium with 113.2 mM dissolved inorganic carbon. The highest CO2 fixation rate of 21.98 ± 1.52 mg/L/h was followed by higher lipid content (49.91 % dry weight content or %dwc) than the generated carbohydrate (24.22 %dwc). TCL-1 also potentially produced phycocyanin that was dominated by C-phycocyanin (98.10 ± 6.67 mg/g) along with a lower amount of allophycocyanin and phycoerythrin under extraction using various types of solvent. Stability of phycocyanin extract was further examined during storage under various temperatures and light illuminations. Extraction with 36 % glucose solvent presented a protective effect to phycocyanin from heat and photo-damage which was proven by the kinetics study of phycocyanin degradation in this study.

Simultaneous 17ß-estradiol degradation, carbon dioxide fixation, and carotenoid accumulation by Thermosynechococcus sp. CL-1.

Thermosynechococcus sp. CL-1 (TCL-1) has a high potency to utilize CO2 under extreme conditions including high temperature, alkaline condition, and the occurrence of 17ß-estradiol (E2). In this study, TCL-1 cultivation with E2 addition in the range of 0-20 mg/L was combined with various growth arrangements (light intensity and dissolved inorganic nitrogen/DIN level). After 120 h cultivation, the 1.0 mg/L E2, 200 µmol photons/m2/s light intensity, and 5.8 mM available nitrogen performed the best growth with 4.58 ± 0.18 mg/L/h biomass productivity, 94.9 ± 3.3% total estrogen removal, and 11.41 ± 0.11 mg/L/h CO2 fixation rate. Estrogen degradation was mainly carried out by biodegradation route which started from E2 conversion into estrone/E1 and with only 4-6% influence from the abiotic factors. Compared with the accumulated zeaxanthin, ß-carotene was dominantly generated with a productivity of 0.043 ± 0.019 mg/L/h. Therefore, TCL-1 cultivation is an efficient strategy for simultaneous CO2 fixation, estrogen removal, and carotenoid accumulation as valuable byproducts.

Elimination of inorganic carbon and nitrogen resided in swine wastewater using Thermosynechococcus sp. CL-1 enriched culture.

Nutrient pollution released from highly accumulated swine wastewater is getting concerned due to global warming and waterbody harmful. Traditional combination of nitrification and denitrification is commonly applied to remove carbon and nitrogen compounds resided in various wastewater with disadvantages of high cost and energy requirements. This study applied the thermophilic flat panel photobioreactor (tFPBR) with high growth rate of TCL-1 culture to evaluate the efficiency of inorganic carbon and nitrogen transformation. This 12-h operation resulted that TCL-1 enriched batch, grown in 50 °C and alkaline environment with 1,000 µE/m2/s light intensity, had high potential for CO2 fixation rate of 122.29 ± 9.93 mg/L/h and nitrogen removal rate of 7.76 mg-N/L/h treating swine wastewater, in comparison with comprehensive community involved in carbon and nitrogen cycles in the field-scale anoxic tank. This study provided the Rapid-growing photosynthetic cyanobacteria in place of slow-growing autotrophic microbes for of carbon and nitrogen transformation in the wastewater system.

Nitrogen and 17ß-Estradiol level regulate Thermosynechococcus sp. CL-1 carbon dioxide fixation, monosaccharide production, and estrogen degradation.

Thermosynechococcus sp. CL-1 (TCL-1), a thermophilic cyanobacterium from a hot spring in Taiwan, has been known of its efficiency in CO2 fixation, byproducts production (pigments, macromolecules). This study observed the performance of TCL-1 in CO2 fixation, estrogen degradation, and monosaccharide production under various levels of Dissolved Inorganic Nitrogen (DIN) and 17ß-estradiol (E2) as nitrogen supply and estrogen addition. Under nitrogen starvation, TCL-1 performed similar results on CO2 fixation rate and biomass production but enhanced the monosaccharide production compared to the cases of high nitrogen supply. The highest CO2 fixation rate and glucose productivity reached to 151.8 ± 6.6 and 38.1 ± 0.9 mg/L/h, under DIN level of 0.58 mM and 0.5 mg/L E2. Adding E2 in the system did not inhibit the performance of TCL-1. During the cultivation, TCL-1 converted E2 into E1 and the biodegradation was the main path for estrogen degradation. Total E2 degradation reached to 69.4 ± 2.0%.

Quantitative PCR based detection system for cyanobacterial geosmin/2-methylisoborneol (2-MIB) events in drinking water sources: Current status and challenges.

Taste and odor (T&O) are an important issue in drinking water, aquaculture, recreation and a few other associated industries, and cyanobacteria-relevant geosmin and 2-methylisoborneol (2-MIB) are the two most commonly detected T&O compounds worldwide. A rise in the cyanobacterial blooms and associated geosmin/2-MIB episodes due to anthropogenic activities as well as climate change has led to global concerns for drinking water quality. The increasing awareness for the safe drinking, aquaculture or recreational water systems has boost the demand for rapid, robust, on-site early detection and monitoring system for cyanobacterial geosmin/2-MIB events. In past years, research has indicated quantitative PCR (qPCR) as one of the promising tools for detection of geosmin/2-MIB episodes. It offers advantages of detecting the source organism even at very low concentrations, distinction of odor-producing cyanobacterial strains from non-producers and evaluation of odor producing potential of the cyanobacteria at much faster rates compared to conventional techniques.The present review aims at examining the current status of developed qPCR primers and probes in identifying and detecting the cyanobacterial blooms along with geosmin/2-MIB events. Among the more than 100 articles about cyanobacteria associated geosmin/2-MIB in drinking water systems published after 1990, limited reports (approx. 10 each for geosmin and 2-MIB) focused on qPCR detection and its application in the field. Based on the review of literature, a comprehensive open access global cyanobacterial geosmin/2-MIB events database (CyanoGM Explorer) is curated. It acts as a single platform to access updated information related to origin and geographical distribution of geosmin/2-MIB events, cyanobacterial producers, frequency, and techniques associated with the monitoring of the events. Although a total of 132 cyanobacterial strains from 21 genera and 72 cyanobacterial strains from 13 genera have been reported for geosmin and 2-MIB production, respectively, only 58 geosmin and 28 2-MIB synthesis regions have been assembled in the NCBI database. Based on the identity, geosmin sequences were found to be more diverse in the geosmin synthase conserved/primer design region, compared to 2-MIB synthesis region, hindering the design of universal primers/probes. Emerging technologies such as the bioelectronic nose, Surface Enhanced Raman Scattering (SERS), and nanopore sequencing are discussed for future applications in early on-site detection of geosmin/2-MIB and producers. In the end, the paper also highlights various challenges in applying qPCR as a universal system of monitoring and development of response system for geosmin/2-MIB episodes.

Improvement of Thermosynechococcus sp. CL-1 performance on biomass productivity and CO2 fixation via growth factors arrangement.

The enormous attraction on CO2 biofixation using photosynthetic microorganisms such as cyanobacteria has been risen due to its promising efficiency and valuable by-products production. In this study, an isolated cyanobacterium from hot spring in Taiwan, Thermosynechococcus sp. CL-1 (TCL-1) was evaluated for its growth factors arrangement effect on the biomass productivity and CO2 biofixation. The initial biomass concentration, and nutrient supply level variation influenced TCL-1 biomass productivity and CO2 biofixation rate while the adjusted and controlled pH value gave an insignificant difference on its performance. The initial biomass concentration of 3 g L-1 gave the best result on biomass productivity and CO2 fixation which reached 143.4 mg L-1 h-1 and 224 mg L-1 h-1 respectively. Regarding to the result of this study, controlled pH value by the CO2 supply inside the reactor, produced an insignificant difference in TCL-1 performance compared to those with the uncontrolled pH value. The variation of nutrient supply level was achieved by the variation of macronutrient and micronutrient supply inside the medium. The G-solution contains metals and other micronutrient elements which are necessary for the growth of TCL-1. The combination between 5-folds MF medium as the macronutrient, and 3-folds G-solution as the micronutrient supply, present the best TCL-1 performance on biomass productivity and CO2 fixation rate.

Comparative Genomic Analysis of a Novel Strain of Taiwan Hot-Spring Cyanobacterium Thermosynechococcus sp. CL-1.

Thermosynechococcus is a genus of thermophilic unicellular cyanobacteria that are dominant in microbial mats at about 50-65°C in alkaline hot springs of eastern Asia. We used PacBio SMRT Sequencing to sequence the complete genome of a novel strain of thermophilic cyanobacterium, Thermosynechococcus sp. CL-1, isolated from the Chin-Lun hot spring (pH 9.3, 62°C) in Taiwan. Genome-scale phylogenetic analysis and average nucleotide identity (ANI) results suggested that CL-1 is a new species in the genus Thermosynechococcus. Comparative genome analysis revealed divergent genome structures of Thermosynechococcus strains. In addition, the distinct genetic differences between CL-1 and the other Thermosynechococcus strains are related to photosynthesis, transporters, signal transduction, the chaperone/usher system, nitric oxide protection, antibiotic resistance, prokaryotic immunity systems, and other physiological processes. This study suggests that Thermosynechococcus strains have actively acquired many putative horizontally transferred genes from other bacteria that enabled them to adapt to different ecological niches and stressful conditions in hot springs.

Measurement of Total Free Iron in Soils by H2S Chemisorption and Comparison with the Citrate Bicarbonate Dithionite Method.

Free iron is one of the major analytical items for soil basic properties. It is also an important indicator for understanding the genesis of soil, soil classification, and soil distribution behavior. In this study, an alternative analytical method (chemisorption) based on thermodynamic knowledge was proposed for measurement of total free iron oxides in soils. Several representative soil samples belonging to alfisols, ultisols, inceptisols, and entisols were collected from Taiwan and tested by the chemisorption, and the estimated total free iron oxides were compared with those measured from the traditional citrate bicarbonate dithionite (CBD) method. Experimental results showed that the optimal operating temperature was found to be at 773 K and the carbon monoxide (CO) is the best gaseous reagent to promote the formation of FeS. The estimated total free iron oxides for soil samples determined from the chemisorption in the presence of CO were very close to those from the CBD technique. The result of regression indicates that the estimated total free iron is strongly correlated with the CBD-Fe content (R2 = 0.999) in the presence of CO.

Effects of light availability on the biomass production, CO2 fixation, and bioethanol production potential of Thermosynechococcus CL-1.

A thermophilic cyanobacterium named Thermosynechococcus CL-1 (TCL-1) was cultivated in this study to eliminate the energy input of cooling system in flat plate photobioreactors. Cultivating TCL-1 in the 1.5 cm light path flat plate photobioreactor exhibited stable characteristics for biomass production, CO2 fixation, and carbohydrate production under high illumination conditions (1000 or 2000 µE m(-2) s(-1)). The greatest biomass and carbohydrate productivity, and CO2 fixation rate were recorded at 116, 67, and 170 mg/L/h, respectively, in the 1.5c m light path photobioreactor and under optimal biomass concentration (about 3 g/L). Cultivating Thermosynechococcus CL-1 in flat plate photobioreactors exhibits high potential for biomass production, CO2 fixation and bioethanol production.

Effects of dissolved inorganic carbon and nutrient levels on carbon fixation and properties of Thermosynechococcus sp. in a continuous system.

The concept of CO(2) chemo-absorption by sodium hydroxide in a wet scrubber followed by microalgae cultivation was used as a means to reduce the major greenhouse gas. A thermophilic and alkaline tolerable cyanobacterium named Thermosynechococcus CL-1 (TCL-1) was cultivated in continuous system, with a carbonate-bicarbonate buffer as carbon source. The effects of dissolved inorganic carbon (DIC(in)) and nutrient levels in influent on cell mass productivity, DIC removal efficiency, and alkaline solution regeneration by TCL-1 were investigated. The results show the highest cell mass productivity reaches 1.7 g L(-1)d(-1) under the highest DIC and nutrients level. Conversely, the best regeneration of alkaline solution proceeds from pH 9.5 to 11.3 under the lowest level. In addition, the highest ΔDIC (DIC consumption) and DIC removal efficiency are 42 mM and 43% at 113.2 and 57 mM DIC(in), respectively.

A feasibility study of a predictive emissions monitoring system applied to taipower's nanpu and hsinta power plants.

The Hsinta and Nanpu Power Stations are located in southern Taiwan. The Hsinta Power Station consists of five combined-cycle gas turbines (CCGT), whereas the Nanpu Power Station consists of four. A project was undertaken to develop and deploy a predictive emissions monitoring system (PEMS) on CCGT unit 3 of Hsinta Power Station (HT-3) and CCGT unit 1 of Nanpu Power Station (NP-1) with the long-term goal of developing a universal model for this kind of power plant. After the first-year PEMS project at the Hsinta power plant, one goal of the second-year PEMS project was to set up a second PEMS at the Nanpu power plant and compare the PEM models applied the to two gas-fired combined cycle power generation units. Consequently, the second and third PEMS of Taiwan at CCGT HT-3 and NP-1 were finished. After comparing the differences among HT-1, HT-3, and NP-1 PEMS models, the pattern of model functionality indicated that this model could be applied to the other units of the same type and size. However, the PEMS function constant or parameter coefficients must be modified on a case-by-case basis. With regard to the PEMS model developed for HT-3, the relative accuracy (RA) of the 15-variable model with start-up mode is only 7.43% and met the criteria of draft PS-16. With regard to the PEMS model developed for NP-1, the RA of the 10-variable model with start-up mode was only 7.76% and also met the criteria of draft PS-16.

Spectroscopic study on the zinc-contaminated soils for the determination of zinc speciation.

The purpose of this paper reported the zinc species in the highly contaminated soils from metallurgical area around Erh-Jen River in the southern of Taiwan. FTIR and XPS were used to investigate the zinc species in the contaminated soils. Through a FTIR analysis, appreciable of zinc bound by organic matter was found and their bonding structure consisted of antisymmetric and symmetric stretchings, Zn-HSsym and Zn-HSasym. With XPS analysis, the Angstrom scale depth scan was surveyed for investigation the zinc speciation. No signal of zinc was detected in the depth of 900A for the larger particle contaminated soils whereas the detectable signal of zinc was determined in the XPS experiment. With further regression and fitting results, the major zinc species presented in the surface of larger and fine particle contaminated soils consisted of reductive and oxidative zinc species. In the deeper depth of contaminated soils, an inverse spinel zinc ferrite was found in the case of larger particle soil. No inverse spinel zinc ferrite was detected in the case of fine particle soil and could be attributed to the relatively small particle size.