Sub-lethal pharmaceutical hazard tracking in adult zebrafish using untargeted LC–MS environmental metabolomics

Sotto, Ryan B. De,Medriano, Carl D.,Cho, Yunchul,Kim, Hyuk,Chung, In-Young,Seok, Kwang-Seol,Song, Kyung Guen,Hong, Seok Won,Park, Youngja,Kim, Sungpyo Elsevier 2017 Journal of hazardous materials Vol.339 No.-

<P><B>Abstract</B></P> <P>Antibiotics in the aquatic environment are dispersed through anthropogenic activities at low concentrations. Despite their sub lethal concentration, these biologically active compounds may still have adverse effects to non-target species. This study examined the response of adult zebrafish to 0.1mg/L concentration of clarithromycin, florfenicol, sulfamethazine, and their mixture using environmental metabolomics. Embryo and larvae of the fish were also used to assess fish embryo acute toxicity and behavior tests respectively. The fish embryo toxicity test did not show any inhibition of growth and development of the embryos after 96h of exposure to the antibiotics. Changes in swimming activity were seen in 5-dpf larvae which is believed to be correlated with the length of exposure to the compounds. Meanwhile, environmental metabolomics revealed diverse metabolites and pathways that were affected after 72h of exposure of the adult fish to sub-lethal concentration of the compounds. We found that even at low concentration of the antibiotics, behavioral and metabolic effects were still observed despite the lack of visible morphological changes. Further studies involving other aquatic organisms and bioactive compounds are encouraged to strengthen the findings presented in this novel research.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Individual and mixture of antibiotics at 0.1mg/L did not impair growth of embryos. </LI> <LI> Zebrafish larvae preferred blue over yellow regardless of antibiotic’s presence. </LI> <LI> Swimming behavior of 5-dpf larvae significantly changed relative to exposure time. </LI> <LI> Metabolites choline, guanosine, and ADP were regulated in the exposed zebrafish. </LI> <LI> Antibiotics’ mechanism of action seems to play a role in zebrafish’s metabolism. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Binary metal oxides for composite ultrafiltration membranes

Sotto, A.,Kim, J.,Arsuaga, J. M.,delRosario, G.,Martinez, A.,Nam, D.,Luis, P.,VanderBruggen, B. Royal Society of Chemistry 2014 Journal of Materials Chemistry A Vol.2 No.19

Effects of solids retention time on the fate of tetracycline resistance in SBRs for the treatment of carcass leachate

De Sotto, R.B.,Medriano, C.A.D.,Salcedo, D.E.,Lee, H.,Cho, Y.,Kim, S. Academic Press 2016 Journal of Environmental Management Vol. No.

<P>In the event of a foot and mouth disease outbreak, further spread of the virus is generally prevented by culling of infected animals in burial pits. This practice may eventually lead to groundwater contamination through leaching of wastewater from the animal carcasses. Wastewater from carcass leachate often contains antibiotic resistant bacteria and genes as well as traces of pharmaceuticals, and a high nutrient content. The role of operational parameters used in activated sludge treatment of this wastewater in the spread of antibiotic resistance has not been fully understood. This study investigated the fate of tetracycline-resistant bacteria and genes in sequencing batch reactors with synthetic carcass leachate at different solid retention times. Escherichia coli DH5 alpha was used as the representative tetracycline-resistant bacteria with multiple antibiotic-resistant genes encoded in plasmid pB10. Solids retention time contributed to an increase in antibiotic resistance in SBRC (SRT = 25 days) with TRB values up to 1.25 x 107 CFU/mL which is one log higher than the influent. Microbial community analysis of the DNA samples from effluent of SBRC showed four major phyla: Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria under which are ecologically-important microbial species. It was shown that antibiotic resistance genes cannot be eliminated during treatment of synthetic carcass leachate in a lab-scale sequencing batch reactor. (C) 2016 Elsevier Ltd. All rights reserved.</P>

Significance of metabolite extraction method for evaluating sulfamethazine toxicity in adult zebrafish using metabolomics

De Sotto, R.,Medriano, C.,Cho, Y.,Seok, K.S.,Park, Y.,Kim, S. Academic Press 2016 Ecotoxicology and environmental safety Vol.127 No.-

<P>Recently, environmental metabolomics has been introduced as a next generation environmental toxicity method which helps in evaluating toxicity of bioactive compounds to non-target organisms. In general, efficient metabolite extraction from target cells is one of the keys to success to better understand the effects of toxic substances to organisms. In this regard, the aim of this study is (1) to compare two sample extraction methods in terms of abundance and quality of metabolites and (2) investigate how this could lead to difference in data interpretation using pathway analysis. For this purpose, the antibiotic sulfamethazine and zebrafish (Danio rerio) were selected as model toxic substance and target organism, respectively. The zebrafish was exposed to four different sulfamethazine concentrations (0, 10, 30, and 50 mg/L) for 72 h. Metabolites were extracted using two different methods (Bligh and Dyer and solid phase extraction). A total of 13,538 and 12,469 features were detected using quadrupole time-of-flight liquid chromatography mass spectrometry (QTOF LC-MS). Of these metabolites, 4278 (Bligh and Dyer) and 332 (solid phase extraction) were found to be significant after false discovery rate adjustment at a significance threshold of 0.01. Metlin and KEGG pathway analysis showed comprehensive information from fish samples extracted using Bligh and Dyer compared to solid phase extraction. This study shows that proper selection of sample extraction method is critically important for interpreting and analyzing the toxicity data of organisms when metabolomics is applied. (C) 2016 Elsevier Inc. All rights reserved.</P>

Identification of metabolites produced by <i>Phanerochaete chrysosporium</i> in the presence of amlodipine orotate using metabolomics

De Sotto, R. B.,Kim, K. I.,Kim, S.,Song, K. G.,Park, Y. IWA Publishing 2015 Water Science & Technology Vol.72 No.7

<P>Pharmaceuticals are very useful in treating human diseases but they are excreted to the environment sometimes in their original form or as byproducts of human metabolism. Pharmaceuticals and their metabolites have been proven by studies to be harmful to non-target ecological species and may be persistent in different water matrices. In this regard, there is an emergent need to eliminate these compounds to prevent their adverse effects on aquatic species. Biodegradation using white-rot fungi is a promising technology for the removal of recalcitrant compounds; however, products of fungal biodegradation can also be detrimental. In this novel study, we evaluated the ability of <I>Phanerochaete chrysosporium</I> to degrade amlodipine, an anti-hypertensive drug which was recently found in water systems. Analysis of amlodipine metabolites was done using quadrupole time-of-flight liquid chromatography mass spectrometry after the degradation set-up of 120 hours. Pharmaceutical degradation was seen using triple quadrupole liquid chromatography tandem mass spectrometry. Ninety-two significant metabolites (<I>P</I>-value ≤ 0.05) were significantly expressed after false discovery rate adjustment at a significance threshold of <I>q</I> = 0.05. Pyridine derivatives which were identified from samples became the basis of the proposed degradation pathway of amlodipine in this study.</P>

Effects of low concentration of clarithromycin to Danio rerio after acute exposure through metabolic analysis

Ryan De Sotto,Carl Medriano,Youngja Park,Sungpyo Kim 한국방재학회 2015 한국방재학회 학술발표대회논문집 Vol.14 No.-

The presence of pharmaceuticals in the environment has led to apparent toxicity with different aquatic species. Clarithromycin, for example, is used in treating respiratory tract infections, has been recently found in the surface waters and rivers which might threaten non-targeted organisms in these matrices. In this study, a model vertebrate Danio rerio (zebrafish) was exposed to 100ppb clarithromycin for 72 hours to evaluate acute toxicity through significantly affected metabolic compounds in the fish’s pathway. Metabolites obtained from q-TOF LC/MS were identified and mapped with the zebrafish’s metabolic pathway using Metlin, and KEGG respectively. 335 compounds are believed to have been significantly altered by the acute exposure of the antibiotic with the fish. The most affected pathways are ABC transporters, steroid hormone biosynthesis, arachidonic acid metabolism, purine metabolism, and biosynthesis of amino acids. With the said findings, it can be concluded that, although concentration of some pharmaceuticals may be as low as the one used in this study, its effects on the aquatic species exposed to it might be significant and should be given immediate attention

Effects of micro-contaminant mixture on the potential toxicity of zebrafish using metabolomics

Ryan De Sotto(라이언 디 소토),Kwangsik Park(박영자),Sungpyo Kim(김성표) 환경독성보건학회 2016 한국독성학회 심포지움 및 학술발표회 Vol.2016 No.6

Nutrient Load Estimates for Manila Bay, Philippines using Population Data

Lara Patricia A. Sotto,Arthur H. W. Beusen,Cesar L. Villanoy,Lex F. Bouwman,Gil S. Jacinto 한국해양과학기술원 2015 Ocean science journal Vol.50 No.2

A major source of nutrient load to periodically hypoxic Manila Bay is the urban nutrient waste water flow from humans and industries to surface water. In Manila alone, the population density is as high as 19,137 people/km2. A model based on a global point source model by Morée et al. (2013) was used to estimate the contribution of the population to nitrogen and phosphorus emissions which was then used in a water transport model to estimate the nitrogen (N) and phosphorus (P) loads to Manila Bay. Seven scenarios for 2050 were tested, with varying degrees and amounts for extent of sewage treatment, and population growth rates were also included. In scenario 1, the sewage connection and treatment remains the same as 2010; in scenario 2, sewage connection is improved but the treatment is the same; in scenario 3, the sewage connection as well as treatment is improved (70% tertiary); and in scenario 4, a more realistic situation of 70% primary treatment achieved with 100% connection to pipes is tested. Scenarios 5, 6, and 7 have the same parameters as 1, 2, and 3 respectively, but with the population growth rate per province reduced to half of what was used in 1, 2, and 3. In all scenarios, a significant increase in N and P loads was observed (varying from 27% to 469% relative to 2010 values). This was found even in scenario 3 where 70% of the waste water undergoes tertiary treatment which removes 80% N and 90% P. However, the lowest increase in N and P load into the bay was achieved in scenarios 5 to 7 where population growth rate is reduced to half of 2010 values. The results suggest that aside from improving sewage treatment, the continued increase of the human population in Manila at current growth rates will be an important determinant of N and P load into Manila Bay.

A new outlook on membrane enhancement with nanoparticles: The alternative of ZnO

Balta, S.,Sotto, A.,Luis, P.,Benea, L.,Van der Bruggen, B.,Kim, J. Elsevier Scientific Pub. Co 2012 Journal of membrane science Vol.389 No.-

Although several studies explored the use of nanoparticles as additives in membrane structures, mixed matrix membranes still suffer from difficulties in synthesis and applications. In this paper, a new outlook on enhancement of membranes with nanoparticles is proposed by using ZnO as an alternative to TiO<SUB>2</SUB>. Although ZnO has attractive features that potentially could fill the objectives of mixed matrix membranes with lower cost and better performance, challenges in development remain. This paper investigates the synthesis of ZnO enhanced membranes and evaluates the performance of mixed matrix membranes with ZnO nanoparticles. Polyethersulfone (PES) membranes manufactured by diffusion induced phase inversion in N-methyl-pyrrolidone (NMP) using a range of procedures were blended with ZnO nanoparticles in a wide range of concentrations from ultralow to high (0.035-4wt%). It was shown that the new membrane materials embedded with ZnO nanoparticles have significantly improved membrane features. The influence of the ZnO nanoparticles on the characteristics of PES/ZnO membranes was investigated with microscopic observations, contact angle measurement, filtration experiments, fouling resistance determination and observation of the rejection of selected dyes. The results showed an overall improvement compared to the neat membranes in terms of permeability as well as dye rejection and fouling resistance by adding ZnO nanoparticles even in small and ultralow concentrations.

Embedding TiO₂ nanoparticles versus surface coating by layer-by-layer deposition on nanoporous polymeric films

Kim, J.,Sotto, A.,Chang, J.,Nam, D.,Boromand, A.,Van der Bruggen, B. Elsevier 2013 Microporous and mesoporous materials Vol.173 No.-

Hybrid polymeric films based on titania (TiO<SUB>2</SUB>) nanoparticles on a polyethersulfone (PES) support were obtained by embedding nanoparticles, by dipping in a single layer and by layer-by-layer assembly. First, TiO<SUB>2</SUB> nanoparticles were doped into a polymeric film during phase-inversion. The permeate flux of TiO<SUB>2</SUB>-embedded membranes in (nano)filtration was higher than for the bare PES membrane in the ultralow concentration range of TiO<SUB>2</SUB> nanoparticles (0.035-0.125wt.%). At the highest concentration of TiO<SUB>2</SUB> nanoparticles tested (0.375wt.%), however, the permeate flux decreased significantly. Compared to the TiO<SUB>2</SUB>-embedded membrane, the permeate flux of TiO<SUB>2</SUB>-deposited membranes prepared by dipping in one single layer was relatively low. After applying layer-by-layer coating, the permeate flux increased considerably as the number of coating layers was increased to >10. SEM images showed that addition of TiO<SUB>2</SUB> nanoparticles during phase inversion resulted in larger finger-like pores in the membrane structure, without changing the surface structure. TiO<SUB>2</SUB>-deposited PES membranes prepared by the layer-by-layer coating proved to have a porous coating layer of TiO<SUB>2</SUB> nanoparticles, covering the surface completely. The surface of TiO<SUB>2</SUB>-deposited films proved to be less rough than that of the bare PES membranes. Release of TiO<SUB>2</SUB> nanoparticles from the membrane surface was not observed during cross-flow filtration, indicative of strong binding of TiO<SUB>2</SUB> nanoparticles on the membrane surface. Similar rejections of humic acid were observed for bare PES membranes and TiO<SUB>2</SUB>-multilayer coated PES membranes, confirming that the membrane structure was not damaged by increasing the number of coating layers of TiO<SUB>2</SUB> nanoparticles on the membrane surface.