Nitrite Removal Research Articles

Evaluation of corncob as a bio-carrier for the enrichment of anammox bacteria using activated sludge as seed

Abstract Anammox is the most sustainable way to remove inorganic nitrogen from wastewater. The feasibility of corncob as bio-carrier for the enrichment of anammox bacteria using activated sludge as inoculum in lab-scale sequencing batch reactors (SBRs) was studied. Control experiments using Levapor® carrier and without carrier were also conducted. Nitrite was completely removed without utilizing NH4+-N when corncob used as carrier in SBR. These results revealed that corncob is not a suitable carrier for anammox enrichment as it supports the growth of denitrifying bacteria. NH4+-N removals were observed after 80 d in control SBRs (with and without Levapor® carrier). The average NH4+-N removals in control and Levapor® carrier set-ups were almost similar (11.92% and 9.17%, respectively) between 80 and 119 d. However, the nitrite removal was significantly higher using Levapor® carriers (36.47%) than control experiment (3.33%). These preliminary results indicate the feasibility of activated sludge as seed for the enrichment of anammox bacteria.

Efficient toxic nitrite monitoring and removal from aqueous media with ligand based conjugate materials

This study aims to develop a highly selective conjugate material for efficient optical detection and adsorption of nitrite (NO2−) ion from waste solutions. In the present study, 1-naphthylamine ligand based conjugate material was fabricated for efficient NO2− capturing. The material was formed color and corresponding signal intensity upon addition of NO2− ion. Several experimental parameters such as materials morphology, solution acidity, contact time, competing ion, elution, maximum adsorption capacity were determined. The data clarified that the material was able to recognize the trace level NO2− based on the limit of detection of 0.23 μg/L. The solution pH was exhibited the key role and the suitable pH 4.0 was selected based on the signal intensity and adsorption efficiency. The competing ion was not affected the NO2− ion detection and removal by the material. In addition, the signal intensity was observed only for the NO2− ions and this was clarified the high selectivity towards the NO2− ions at the optimum experimental conditions. Moreover, the adsorption data were highly fitted to the Langmuir adsorption model with the monolayer coverage as the material surface was ordered homogeneity. The maximum adsorption capacity was 135.21 mg/g, which was comparable with the other forms of recent material. The materials was exhibited the high reusability based on the desorption performances. The elution was performed using 0.20 M NaOH and then the material was ready to use after washing with water without significant loss in its performance. Therefore, the data are promising to use the material in real samples treatment. Moreover, the proposed materials will attract the scientific community as suitable nanomaterial for NO2− detection and removal from contaminated water samples.

Reducing environmental impact of recirculating aquaculture systems by introducing a novel microaerophilic assimilation reactor: Modeling and proof of concept

Use of recirculating aquaculture systems (RAS) to grow fish is on the rise. Fish feed typically contains 25–60% protein and is the only significant input in RAS. Fish recover 20–30% of the applied feed as biomass, and the unassimilated nitrogen is released into the water, mainly as ammonia, which is toxic to fish. Nitrification is the most common treatment practice, converting ammonia to the less toxic nitrate, and nitrogen removal is achieved by either water exchange or denitrification. The aim of this study was to develop and test a novel approach to remove nitrogen based on a microaerophilic assimilation side-reactor. In the suggested system, fish solid waste and dissolved nitrogen are assimilated into protein-rich microbial biomass, which has the potential to partially offset fish feed input. Initially, a theoretical model based on the system’s nitrogen mass balance was established. Then, an intensive pilot-scale RAS was constructed, growing ∼50 kg fish/m3. The system consisted of a fish tank, solids filter, and microaerophilic assimilation reactor based on activated sludge treatment. Intrinsic solid waste and wheat-flour waste were used as carbon source. After a trial run of about 2.5 months, the RAS was tested for 101 days. Average total ammonia nitrogen, nitrite, and nitrate removal were 89.1, 69.4 and 100%, respectively. Of the introduced solids, over 82% were lost as carbon dioxide by respiration, 11.7% were recovered as microbial biomass and 6.5% as fish biomass, and only 0.6% remained in the water. Biomass organic content was similar to aquafeed and nitrogen content was equivalent to 40% crude protein. Daily energy demand for the system’s designed capacity of 80 kg/m3 would result in a low energy consumption of 7.72 kW h/kg fish. Overall, a novel concept for sustainable production in intensive aquaculture was developed and successfully demonstrated in a pilot-scale RAS.

Photocatalytic Simultaneous Removal of Nitrite and Ammonia via a Zinc Ferrite/Activated Carbon Hybrid Catalyst under UV-Visible Irradiation.

Nitrite and ammonia often coexist in waters. Thus, it is very significant to develop a photocatalytic process for the simultaneous removal of nitrite and ammonia. Herein, zinc ferrite/activated carbon (ZnFe2O4/AC) was synthesized and characterized by X-ray diffraction spectroscopy, transmission electron microscopy, Raman spectroscopy, and ultraviolet–visible diffuse reflectance spectroscopy. The valence band level of ZnFe2O4 was measured by X-ray photoelectron spectroscopy–valence band spectroscopy, and first-principles calculation was performed to confirm the band structure of ZnFe2O4. The as-synthesized ZnFe2O4/AC species functioned as a photocatalyst to simultaneously remove nitrite and ammonia under anaerobic conditions upon UV–visible light irradiation at the first stage. The results indicated that an average removal ratio of 92.7% with ±0.2% error for nitrite degradation for three runs was achieved in 50.0 mg/L nitrite + 100.0 mg/L ammonia solution with pH 9.5 under anaerobic conditions for 3 h at this stage; simultaneously, the removal ratio of 64.0% with ±0.2% error for ammonia was also achieved. At the second stage, oxygen gas was bubbled in the reactor to photocatalytically eliminate residual ammonia under aerobic conditions upon continuous irradiation. The results demonstrated that the removal ratios for nitrite, ammonia, and total nitrogen reached to 92.0, 90.0, and 90.2% at 12th hour, respectively, and the product released during photocatalysis is N2 gas, detected by gas chromatography, fulfilling the simultaneous removal of nitrite and ammonia. The reaction mechanism was exploited.

Removal of nitrogen by heterotrophic nitrification-aerobic denitrification of a novel halotolerant bacterium Pseudomonas mendocina TJPU04.

Excess inorganic nitrogen in water poses a severe threat to enviroment. Removal of inorganic nitrogen by heterotrophic nitrifying-aerobic denitrifying microorganism is supposed to be a promising and applicable technology only if the removal rate can be maintained sufficiently high in real wastewater under various conditions, such as high concentration of salt and wide range of different nitrogen concentrations. Here, a new heterotrophic nitrifying-aerobic denitrifying bacterium was isolated and named as Pseudomonas mendocina TJPU04, which removes NH4+-N, NO3--N and NO2--N with average rate of 4.69, 5.60, 4.99mg/L/h, respectively. It also maintains high nitrogen removal efficiency over a wide range of nitrogen concentrations. When concentration of NH4+-N, NO3--N and NO2--N was up to 150, 150 and 50mg/L, 98%, 93%, and 100% removal efficiency could be obtained, respectively, after 30-h incubation under sterile condition. When it was applied under non-sterile condition, the ammonia removal efficiency was slightly lower than that under sterile condition. However, the nitrate and nitrite removal efficiencies under non-sterile condition were significantly higher than those under sterile condition. Strain TJPU04 also showed efficient nitrogen removal performance in the presence of high concentration of salt and nitrogen. In addition, the removal efficiencies of NH4+-N, NO3--N and TN in real wastewater were 91%, 52%, and 75%, respectively. These results suggest that strain TJPU04 is a promising candidate for efficient removal of inorganic nitrogen in wastewater treatment.

Substrate inhibition and pH effect on denitritation with granular biomass

Abstract Undissociated HNO2 (up to 2 mg dm−3) was confirmed as substrate inhibitor for granular biomass from a denitritation upflow sludge bed reactor used for biological removal of nitrite. On the contrary, total nitrite nitrogen (N-NO2 up to 500 mg dm−3) and methanol (COD up to 2000 mg dm−3) were not proven to be inhibitors. pH also affected the denitritation efficiency (optimal pH was 5.9). Reduction of HNO2 concentration in the reactor by effluent recycling is recommended.

New Polymer Catalytic Membranes for Nitrite Reduction: Experimental Assessment

In this work we report the experimental assessment of the performance of a new catalytic hollow fiber reactor with supported Pd catalyst for nitrite removal from polluted waters. The reactor configuration facilitates working at low flowrate and hydrogen concentrations in order to improve the selectivity of the reduction reaction towards nitrogen, thus, inhibiting the formation of ammonia. Pd catalyst was supported on propylene and polyethersulfone hollow fibers following a simple impregnation method; the stability of the supported catalyst was checked along the operation time. Experiments of nitrite reduction were carried out in the range of 0.075-1 bar of H2 partial pressure, 0.3-0.4 bar of CO2 partial pressure, 200-400 mL/min of water flowrate and 20-200 mL/min of gas flowrate with an initial nitrite concentration of 150 mg/L. Under the experimental conditions a selectivity to N2 close to 90% with 80% conversion of nitrites was achieved.

Removal of trimethoprim and sulfamethoxazole in artificial composite soil treatment systems and diversity of microbial communities

Four artificial composite soil treatment systems (ACSTs) fed with reclaimed water containing trimethoprim (TMP) and sulfamethoxazole (SMX) were constructed to investigate SMX and TMP biodegradation efficiency, ammonia and nitrite removal conditions and the microbial community within ACST layers. Results showed SMX and TMP removal rates could reach 80% and 95%, respectively, and removal rates of ammonia and nitrite could reach 80% and 90%, respectively, in ACSTs. The MiSeq sequencing results showed that microbial community structures of the ACSTs were similar. The dominant microbial community in the adsorption and biodegradation layers of the ACSTs contained Proteobacteria, Chloroflexi, Acidobacteria, Firmicutes, Actinobacteria and Nitrospirae. Firmicutes and Proteobacteria were considerably dominant in the ACST biodegradation layers. The entire experimental results indicated that Nitrosomonadaceae_uncultured, Nitrospira and Bacillus were associated with nitrification processes, while Bacillus and Lactococcus were associated with SMX and TMP removal processes. The findings suggest that ACSTs are appropriate for engineering applications.

Performance evaluation of an outdoor algal biorefinery for sustainable production of biomass, lipid and lutein valorizing flue-gas carbon dioxide and wastewater cocktail

We evaluated wastewater remediation and CO2 utilization potential of Chlorella minutissima from flue gas in a raceway pond, while synthesizing lutein and lipid for potential healthcare and biofuel application. A mix of 20% kitchen waste, 10 g L−1 of poultry litter waste and 5% flue gas was maintained while cultivating the microalga. Complete removal of nitrate, nitrite and ammonium, 85% carbon and 91% phosphorus was observed. An average areal biomass productivity of 4.06 ± 0.12 g m−2 day−1 with a specific growth rate of 0.34 ± 0.03 day−1 was observed within 9 days. Biomass productivity of 6.21 ± 0.16 g m−2 day−1 with a specific growth rate of 0.34 ± 0.03 day−1 was achieved during winter. Furthermore, lipid content with appropriate fatty acid composition 1.04:1 (saturation:unsaturation) increased from 25% to 58%. Additionally, lutein productivity of 1.2 ± 0.08 mgL−1 day−1, while utilizing 80.74 ± 0.07 mg L−1 day−1 of CO2 from 5% flue gas was obtained.

Application of photosynthetic microalgae as efficient pH bio-stabilizers and bio-purifiers in sustainable aquaculture of <i>Clarias gariepinus</i> (African catfish) fry

Chlorella lewinii LC172265 and Scenedesmus dimorphus NIES-93 were grown with BG-11 medium and then transferred to fish seedlings' farm and the effects on changes in the pH, nitrite, total ammonia nitrogen and toxic ammonia were studied. Inoculation of the ponds with C. lewinii, S. dimorphus and the combined culture of C. lewinii and S. dimorphus significantly reduced the rise in the pH of the ponds (p<0.05). With these three cultures, the pond pH increased from 6.3±0.03 to only 6.5±0.2, 6.7±0.6 and 6.4±0.1 respectively within a period of 240 hours, as against control pond's pH which increased from 6.3±0.03 to 9.0±0.1 within the same period. Furthermore, inoculation with S. dimorphus reduced the nitrite concentration in the ponds to zero on the 144th hour and the concentration remained zero throughout the experiment. This was closely followed by the combined culture of C. lewinii and S. dimorphus which reduced the nitrite concentration to zero at 240th hour while C. lewinii was the least in nitrite removal. Toxic ammonia was also zeroed by the combined culture of C. lewinii and S. dimorphus at 144th hour of experiment which was followed by C. lewinii (at 192nd hour). Aquaculture ponds co-cultured with microalgae witnessed a maximum fry death rate of 40% which was much lower than 80% death rate observed in the control ponds. These results show that C. lewinii and S. dimorphus are very efficient in sustaining the quality of aquaculture water, and thus prolonging the length of time water can be used before changing.Keywords: nitrogen removal, ammonia, nitrite, fishery, fish pond

Effect of external hydrazine addition on anammox reactor start-up time

Hydrazine is an intermediate product of the anaerobic ammonium oxidation (Anammox) process where both ammonium and nitrite in wastewater are converted to nitrogen gas by bacteria. In this study the effect of external hydrazine addition (5, 10, 15, and 20 mg/L) on the start-up period of the Anammox process was studied using sequencing batch reactors (SBRs). The SBR with an addition of 10 mg/L hydrazine took only 7 weeks to stabilize and achieve the maximum removal of ammonium and nitrite, whereas the SBR without the addition of hydrazine took 12 weeks. The amount of Heme C extracted from the biomass indicated that externally added hydrazine accelerated the growth of Anammox bacteria and reduced the release of nitrous oxide gas from the reactors.

Ca(II) and Mg(II) significantly enhanced the nitrogen removal capacity of Arthrobacter arilaitensis relative to Zn(II) and Ni(II)

This study investigated the impacts of alkaline-earth metals [Ca(II), Mg(II)] and heavy metals [Zn(II), Ni(II)] on the nitrogen removal capacity of Arthrobacter arilaitensis Y-10. StrainY-10 was able to tolerate 20 mg/L Ca(II) and its ammonium removal efficiency was 100%. 0.5 mg/L Ca(II) effectively promoted total nitrogen removal from wastewater containing nitrite. Mg(II) supplementation substantially enhanced the bacterial growth and nitrogen reduction. As Mg(II) concentrations increased from 0 to 2 mg/L, the ammonium, nitrate and nitrite removal efficiencies increased by 40.62%, 69.91% and 64.68%, respectively. Although the nitrogen removal ability of strain Y-10 was sharply hindered by Zn(II) and Ni(II), it occurred continuously even when the Zn(II) concentration reached 30 mg/L. However, the ammonium and total nitrogen removal almost stopped at 8 mg/L Ni(II), and the denitrification capacity was lost when the Ni(II) concentration exceeded 1 mg/L. The results demonstrate that Ca(II) and especially Mg(II) could significantly enhance the nitrogen removal capacity of Arthrobacter arilaitensis relative to Zn(II) and Ni(II).

Assessment of enhanced nitrite removal and monitoring using ligand modified stable conjugate materials

In this study, stable conjugate material was fabricated by functional organic ligand embedded onto the porous silica for efficient detection and adsorption of toxic nitrite (NO2−) ions from contaminated water. The detection method was obviously detected the NO2− ions even in the ultra-trace amount with significant color formation. Several experimental frameworks, including pH effect, reaction time, low limit detection, competing ions effect, maximum removal capacity and reuses were investigated systematically both in the detection and removal operations. The low limit of detection was 0.16 µg/L, which was compiled the high-sensitivity detection of the NO2− ions. The solution pH was displayed a key factor, and it was optimized carefully. The optimum pH was 5.50 both in the detection and adsorption mode in this study. The contact time showed that the kinetics performance was slow compared with previous several nanomaterials. This was postulated that the NO2− ions removed as monovalent and consisted in wastewater as anions. The adsorption trend was highly competent according to Langmuir isotherms, and the highest removal capacity was 119.22 mg/g by the conjugate materials for NO2− ions. Several cations and anions were tested as the competing ions, however, these were not affected the NO2− ion in both operations as the strong affinity of the conjugate materials functionality was expected to the NO2− ions at suitable conditions. The data also emphasized that the conjugate material has potentiality under the suitable experimental protocol for the NO2− ions capturing from the polluted waters. Thus the conjugate materials will attract the scientific community in as promising material in nanotechnology for NO2− ions capturing.

Preparation and characterization of sintered clay ceramic membranes water filters

Abstract Metal oxide ceramic is getting more attention in current times due to their unique pore structures, hydrophilic surfaces, high chemical, thermal and mechanical stabilities which offer avenues for application in water treatment. This paper presents the results of an experimental study on the effects of different ratios of clay, grog, sawdust and bone char on efficiency of ceramic composite water filters. Filter of different designs were developed from clay (50, 60, 70, 75 and 80) |%|, sawdust (15, 25, and 35) |%|, grog (5 and 15) |%| bone char and 5|%| ratios by volume and sintered at temperature of 900°C for 6 hours. The Phase and functional group identification of sintered filter investigated with x-ray diffraction and infrared spectroscopy revealed the presence of mixed phase and hydroxyl functional group on the surface of sintered filter. Field emission scanning electron microscopy (FESEM) revealed the porous nature of the microstructures of the sintered filter elements. The superior ceramic water filter design (C900-50-15-35) with total porosity 35.89±0.04|%|, flow rate 2.05±0.41|%| and the percent E coli, nitrite and fluoride removal efficiency: 99.6±0.40 |%|, 81.17±0.22|%| and 96.4±0.42|%| were obtained from this work. Porosity evaluated by BET study for C900-50-15-35 demonstrated an average pore size and surface area of 5 |nm | and 7.30|m2/g|, respectively.

Effective Removal of Nitrate, Nitrite, Ammonia and Iron from Contaminated Ground Water using Bio-Sand Method and Sponge Layer Filtration Method

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The design of a polyaniline-decorated three dimensional W18O49 composite for full solar spectrum light driven photocatalytic removal of aqueous nitrite with high N2 selectivity

Photocatalysis using solar energy is the most promising green technology for nitrite removal. However, effective photocatalytic performance is often challenged by the limited light absorption, utilization of expensive noble metals and undesired products (nitrate and ammonium). Here, we report for the first time that a full solar light response polyaniline-decorated three dimensional W18O49 composite (PANI@W18O49), a noble metal-free photocatalyst, possesses excellent photocatalytic activity for aqueous nitrite removal with high N2 selectivity. The prepared sample was thoroughly identified via XRD, Raman, FTIR, SEM, TEM, UV–vis DRS and PL. The catalytic results demonstrated that over 80% N2 selectivity (initial concentration 1.0 mM) was achieved through the PANI@W18O49 without sacrificial agent under 300 W Xe lamp irradiation for 60 min. Such advantages were attributed to the built-in junction between n-type W18O49 and p-type PANI, offering suitable redox levels of electron-hole pairs for NO2− reaction. The modification of PANI also benefited the light harvesting ability and activated carriers migration, the calculated rate constant of PANI@W18O49 is about four times as high as that of W18O49. The current study not only prepared a promising photocatalyst, but also provides new insights into improving the photocatalytic activity and N2 selectivity for nitrite treatment.

Effects of abrupt salinity increase on nitrification processes in a freshwater moving bed biofilter

The nitrification process is a widely used biological approach responsible for ammonia and nitrite removal in recirculating aquaculture system (RAS) biofilters. Given this pivotal role, the influence of different water quality parameter on nitrification efficiency is important information for RAS operations. One influencing parameter is salinity, and salinity fluctuations in freshwater RAS biofilters are reported to affect the nitrifying bacteria. This study investigated the effects of abrupt increase in salinity in freshwater RAS on substrate-dependent (1’-order) as well as substrate independent (0’-order) nitrification rates. A 100% inhibition was found for surface specific removal (STR) of total ammonia nitrogen (TAN) and surface specific nitrite removal (SNR) when salinity was abruptly increased to 25‰ and above. A fast turnover (i.e. steep decline in [NH4-N+] and [NO2-N−]) were observed at lower salinities (≤10‰), while limited/no degradation of either ammonia or nitrite was seen at salinities above 25‰. At low substrate loading (1’-order process), removal rate constants (k1a) of 0.22 and 0.23 m d-1 were observed for ammonia and nitrite degradation, respectively, declining to 0.01 m d-1when adding marine RAS water increasing the salinity to 15‰. Similar observations followed at high nutrient loadings (0’-order process) with STR and SNR of 0.10 and 0.12 g N m-2 d-1, respectively, declining to 0.01 g N m-2 d-1 at 15‰. When salinities of 25‰ and 35‰ were applied, neither TAN nor nitrite degradation was seen. The results thus demonstrate a pronounced effect of salinity changes when freshwater RAS biofilters are subjected to fast/abrupt changes in salinity. RAS facility operators should be aware of such potential effects and take relevant precautions.

Investigating the effect of copper and magnesium ions on nitrogen removal capacity of pure cultures by modified non-competitive inhibition model

Copper, a common heavy metal, may be beneficial for or poisonous to microbial activity. The objective of this study was to determine the effect of different copper ion concentrations on the nitrogen removal performance of Arthrobacter arilaitensis strain Y-10 and Pseudomonas taiwanensis strain J488. The non-competitive inhibition model was employed to evaluate the 50% inhibition concentrations (IC50 values) of copper ions toward the pure strains. In the absence of magnesium ions, a low concentration of copper (0.1 mg/L) significantly enhanced the ammonium removal ability of strain Y-10 and its removal efficiency increased by 10.88% compared with the control treatment. Copper ranging from 0 to 0.1 mg/L had no significant effect on the ammonium removal capacity of strain J488. After adding 9.90 mg/L of magnesium to the basal medium, the effects of copper on nitrification of ammonium or denitrification of nitrate or nitrite were also assessed. In these conditions, 0.25 mg/L copper ions could strongly inhibit the ammonium, nitrate and nitrite removal activities for strain Y-10. For strain J488, no clear deterioration in ammonium removal efficiency was observed at copper ion concentrations below 0.5 mg/L, but 0.25 mg/L copper ions significantly inhibited nitrate and nitrite removal efficiencies, which were only 45.88% and 6.35%, respectively. The IC50 values of copper ions for nitrate and nitrite removal by strain Y-10 were 0.195 and 0.090 mg/L respectively; for strain J488, the IC50 values were 0.175 and 0.196 mg/L. The magnesium ions could improve the cell growth, nitrogen removal efficiency and copper ion resistance of bacteria.

The co-existence of anammox genera in an expanded granular sludge bed reactor with biomass carriers for nitrogen removal.

Anaerobic ammonium oxidation (anammox)-based nitrogen removal saves aeration energy and organic carbon costs, attributed to its anaerobic and autotrophic nature. However, due to the slow growth of anaerobic ammonium oxidation bacteria (AnAOB), drawbacks including long startup time and sensitivity to toxins still hamper the application of anammox-based processes. To cope with the slow growth of AnAOB, various bioreactor configurations have been investigated for the capability of retaining anammox biomass, among which, the expanded granular sludge bed (EGSB) reactor is a promising option. In this study, two laboratory-scale EGSB reactors were used to gain insights of microbial population and their response to amending biofilm-carriers, aiming to enhance the biomass retention of AnAOB. The respective ammonium and nitrite removal efficiencies were up to over 90%, and the overall nitrogen removal efficiency (NRE) was stable at over 70%, in the EGSB reactor amended with carriers (CEGSB). Compared to the control EGSB, CEGSB's observed performance was more stable during the 236-day operational period. The abundance of AnAOB reached 22% in the EGSB and 49% in the CEGSB. It was also observed that Ca. Brocadia (14.25%) and Asahi BRW2 (33.19%) coexisted in the CEGSB. The dynamics of major metabolisms and functional genes involved in nitrogen conversion were further observed by FAPROTAX based on the taxonomic data, providing more insights into the functions of the microbial communities.

Ammonia nitrogen and nitrite removal by a heterotrophic Sphingomonas sp. strain LPN080 and its potential application in aquaculture

A safe, effective and simple method for ammonia nitrogen and nitrite removal in farming water has always been a goal of environmentally friendly farming models aimed at water saving and reducing the discharge of farming wastes. In this study, it was shown that a bacterial strain LPN080 isolated and screened from a shrimp culture pond can efficiently remove both ammonia nitrogen and nitrite. When supplemented with ammonia nitrogen and glucose in water samples, ammonia nitrogen (as the only nitrogen source) was reduced from an initial 8 mg/l to 0.3 mg/l in 48 h, and a removal rate of ammonia nitrogen of up to 96% was achieved. With the same addition of glucose in the water samples, nitrite (as the only nitrogen source) reduced from an initial 5 mg/l to 0.8 mg/l, and the removal rate was approximately 81% in 48 h. The LPN080 strain was identified as a member of Sphingomonas using 16S rDNA sequencing. Sphingomonas sp. LPN080 could indirectly inhibit the growth of Vibrio spp. in water supplemented with glucose and the inhibition was not caused by the production of antimicrobial substances. Sphingomonas sp. LPN080 showed high biosafety toward shrimp Litopenaeus vannamei. All these results demonstrated that Sphingomonas sp. LPN080 has a potential economic value in aquaculture and even in wastewater treatment.