Achieving Electrochemical-Sustainable-Based Solutions for Monitoring and Treating Hydroxychloroquine in Real Water Matrix

Hydroxychloroquine (HCQ) has been extensively consumed due to the Coronavirus (COVID-19) pandemic. Therefore, it is increasingly found in different water matrices. For this reason, the concentration of HCQ in water should be monitored and the treatment of contaminated water matrices with HCQ is a key issue to overcome immediately. Thus, in this study, the development of technologies and smart water solutions to reach the Sustainable Development Goal 6 (SDG6) is the main objective. To do that, the integration of electrochemical technologies for their environmental application on HCQ detection, quantification and degradation was performed. Firstly, an electrochemical cork-graphite sensor was prepared to identify/quantify HCQ in river water matrices by differential pulse voltammetric (DPV) method. Subsequently, an HCQ-polluted river water sample was electrochemically treated with BDD electrode by applying 15, 30 and 45 mA cm−2. The HCQ decay and organic matter removal was monitored by DPV with composite sensor and chemical oxygen demand (COD) measurements, respectively. Results clearly confirmed that, on the one hand, the cork-graphite sensor exhibited good current response to quantify of HCQ in the river water matrix, with limit of detection and quantification of 1.46 mg L−1 (≈3.36 µM) and 4.42 mg L−1 (≈10.19 µM), respectively. On the other hand, the electrochemical oxidation (EO) efficiently removed HCQ from real river water sample using BDD electrodes. Complete HCQ removal was achieved at all applied current densities; whereas in terms of COD, significant removals (68%, 71% and 84% at 15, 30 and 45 mA cm−2, respectively) were achieved. Based on the achieved results, the offline integration of electrochemical SDG6 technologies in order to monitor and remove HCQ is an efficient and effective strategy.

Identification and Quantification of Bisphenols in Water by Dissipation followed by Silylation using Gas Chromatography-Mass Spectrometry Analysis

Bisphenols are important endocrine disruptors, which were widely used in the variety of food packing and storage materials which often come into contact with various food products packed in them. The presence of bisphenols in water is harmful for the health of humans as well as aquatic animals and also, they accumulate over a period of time. Hence, the present work aimed to develop a simple and accurate GCMS-SIM method for the quantification of bisphenols in packaged drinking water as well as the water samples collected in river and lakes in Andhra Pradesh state of India. Bisphenols were extracted by simple solvent extraction with acetonitrile and silylated by N,O-bis (trimethylsilyl)trifluoro acetamide and analyzed by GC-MS. Various parameters that affect the recovery of the analytes were carefully optimized and the developed method was validated. The recoveries of the analytes were in the range of 80-120 % with quantification limit of 1 ng/L. The calibration curve was linear in the concentration range of 5 ng/L to 10 μg/L. The method was applied for the quantification of bisphenols in packaged drinking water at room temperature and at 50 ºC at various time intervals. The results proved that the water sample kept at room temperature doesn’t shows peaks corresponding to bisphenols. The water sample exposed to 50 ºC for 30 days bisphenols content 10, 12, 22 and 8 ng/L respectively for bisphenol G (BPG), bisphenol F (BPF), bisphenol E, (BPE) and bisphenol A (BPA) whereas the same sample at 180 days of exposer shows 60, 51, 61 and 22 ng/L respectively confirms that the leaching of plastic due to temperature increases the bisphenols level. Among the real time samples studied, the bisphenols level was observed to be very high in Kolleru Lake and it is having 17, 14, 8 and 12 ng/L of BPG, BPF, BPE and BPA, respectively confirms that due to high plastic pollution the bisphenols level was high in these samples. Hence, it can be concluded that the method can be suitable for the analysis of bisphenols in drinking water as well as in wastewater samples.

Remediation of Kalyani River water using plant-bacterial cell synergism

The purpose of this research was to evaluate the potential of plant-immobilized bacterial cells synergism for enhanced remediation of polluted river water. The polluted river water sample was collected from Kalyani river, Uttarakhand, India and characterized by high concentration of COD (1010 mg/l), BOD (230 mg/l), NO3−-N (30 mg/l), PO43−-P (48.9 mg/l), and Pb(1.028 mg/l). This water sample was treated on a lab scale with immobilized bacterial cells and Epipremnum aureum in various treatment setups. The treatment system 3 using a combination of immobilized bacterial cells and Epipremnum aureum had the highest pollutant removal efficiency of all the treatment setups tested. At 96 hours, the total COD, BOD, NO3−-N, PO43−-P and Pb contents of polluted river water sample were reduced to 60 mg/l, 20 mg/l, 2.4 mg/l, 11.7 mg/l, and 0.065 mg/l, respectively. Based on the findings, it is possible to conclude that utilizing plant-immobilized bacterial cell synergism is an environmentally friendly and cost-effective approach for enhanced remediation and rejuvenation of polluted river water. Furthermore, a field-scale application of plant-immobilized bacterial cell synergism via floating wetland construction for on-site treatment of contaminated water on the Kalyani river is recommended.

Characterization of Planococcus dechangensis isolated from a water sample of Çamaltı Saltern

In the present study, strain MHDS3 was isolated from a water sample of Çamaltı Saltern and identified using conventional and molecular methods. 16S rRNA gene sequence analyses showed that the strain MHDS3 belonged to Planococcus dechangensis species. It gave a positive result in the Gram staining test. The cells were coccus, non-motile, aerobic, catalase positive, oxidase negative and the colony pigmentation was yellow-orange. It showed negative results for citrate utilization, indole production from tryptophane, Voges-Proskauer and methyl red. This isolate was able to grow at 10-45°C (optimally 35°C), pH 6-8 (optimally pH 7) and 3-20% NaCl (optimally 10% NaCl). It was not able to grow at 4°C, 10°C, 50°C, salt-free, 0.5%, 25%, %30 total salt, pH 4-5, and pH 9-12. Glucose, ribose, fructose, sucrose, maltose were used by the test isolate as carbon sources. Different amino acids found in the structure of animal hide such as L-lysine, L-arginine, L-cysteine, L-alanine, L-tyrosine, L-histidine were also utilized by the bacterium. During the salt production process, this bacterium may contaminate the salt which is used in the food and leather industries. The activities of harmful moderately halophilic bacteria should be prevented by effective antimicrobial applications.

Filtration extraction method using microfluidic channel for measuring environmental DNA

The environmental DNA (eDNA) method, which is widely applied for biomonitoring, is limited to laboratory analysis and processing. In this study, we developed a filtration/extraction component using a microfluidic channel, Biryu-Chip (BC), and a filtration/extraction method, BC method, to minimize the volume of the sample necessary for DNA extraction and subsequent PCR amplification. We tested the performance of the BC method and compared it with the Sterivex filtration/extraction method using aquarium and river water samples. We observed that using the BC method, the same concentration of the extracted DNA was obtained with 1/20–1/40 of the filtration volume of the Sterivex method, suggesting that the BC method can be widely used for eDNA measurement. In addition, we could perform on-site measurements of eDNA within 30 min using a mobile PCR device. Using the BC method, filtration and extraction could be performed easily and quickly. The PCR results obtained by the BC method were similar to those obtained by the Sterivex method. The BC method required fewer steps and therefore, the risk of DNA contamination could be reduced. When combined with a mobile PCR, the BC method can be applied to easily detect eDNA within 30 min from a few 10 mL of the water sample, even on-site.

Performance and Kinetic Study on Oil Removal Via Electrocoagulation Treatment

Electrocoagulation (EC) is a reliable technology for wastewater treatment. It has been applied in treating various source of wastewater from tannery, electroplating, dairy, textile processing, oil and oil-in-emulsion. It is crucial to strengthen the fundamental of the EC treatment on oily water sample for further studies. However, in depth studies on the performance of EC treatment on oily water sample is still requires in depth studies. In this research, a series of experiment has been conducted on the performance of EC treatment including effect of the amount of sodium chloride (NaCl), applied voltage and pH to determine the efficiency in oil removal. The EC treatment took placed in room temperature and constantly agitated for 30 minutes meanwhile samples were collected for every 5 minutes for UV–Vis analysis. Then, the efficiency of the treatment was determined followed by simulating the results in kinetic models. The highest efficiency of EC treatment was achieved with 89.26% of oil removal with the addition of 7.5g of NaCl, 4V of applied voltage and at pH 6. In addition, the results have better fitness towards pseudo second order (PSO) which indicates the mechanism of EC treatment is chemisorption.

Towards environmental DNA-based bioassessment of freshwater reservoirs with small volumes of water: robust molecular protocols

Bioassessment of freshwater quality via eDNA is rapidly developing into a powerful alternative to traditional methods involving collecting, sorting, and identifying macroinvertebrates based on morphology. Particularly attractive would be methods that can use remote-controlled boats for sampling because it would allow for cost-effective, and frequent monitoring at multiple sites. The latter will be particularly important for tropical reservoirs that require year-around surveillance. We here optimize molecular protocols for capturing reservoir-specific differences in metazoan communities based on small water volumes (15 mL). The optimization is based on samples from two freshwater reservoirs with very different water qualities ("reservoir signal"). Each reservoir was sampled at three sites ("biological replicates"). For each water sample, the DNA was extracted twice ("technical replicates"). We then tested how much DNA template (0.1 ng to 15 ng) and how many PCR cycles (25 or 35) minimized variance between technical replicates. We find that 15 mL is sufficient for capturing the reservoir signal regardless of sampling time, template amounts, or PCR cycle numbers. Indeed, extrapolation from our results suggests that <1 mL would be sufficient because only 17 of 59 metazoan mOTUs (mainly planktonic crustaceans and rotifers) detected with a 313bp COI minibarcode were shared. We find that the use of 35 PCR cycles significantly lowered the number of detected species and that template amounts <0.5 ng yielded somewhat higher variance between technical replicates. Despite extensive trials, the variance between technical replicates remained high (Bray-Curtis: 5-20%; Jaccard: 10-40%) and we predict that it will be difficult to reduce this variance further. However, the overall reservoir differences are so strong that all biological and technical replicates can be correctly assigned.

Filtration extraction method using microfluidic channel for measuring environmental DNA

The environmental DNA (eDNA) method, which is widely applied for biomonitoring, is limited to laboratory analysis and processing. In this study, we developed a filtration/extraction component using a microfluidic channel, Biryu-Chip (BC), and a filtration/extraction method, BC method, to minimize the volume of the sample necessary for DNA extraction and subsequent PCR amplification. We tested the performance of the BC method and compared it with the Sterivex filtration/extraction method using aquarium and river water samples. We observed that using the BC method, the same concentration of the extracted DNA was obtained with 1/20-1/40 of the filtration volume of the Sterivex method, suggesting that the BC method can be widely used for eDNA measurement. In addition, we could perform on-site measurements of eDNA within 30 min using a mobile PCR device. Using the BC method, filtration and extraction could be performed easily and quickly. The PCR results obtained by the BC method were similar to those obtained by the Sterivex method. However, the BC method required fewer steps and therefore, the risk of DNA contamination could be reduced. When combined with a mobile PCR, the BC method can be applied to easily detect eDNA within 30 min from 10 mL of the water sample, even on-site.

Application of water quality index and multivariate statistical techniques for assessment of water quality around Yamuna River in Agra Region, Uttar Pradesh, India

In this research, Water Quality Index and Multivariate Statistics Techniques was carried out on fourteen water quality parameters collected quarterly (four times/year) from nine water sources in Agra, Uttar Pradesh, India for one year (May 2019- April 2020). The Water Quality Parameters (WQP) included are the concentration of hydrogen ion (pH), Electrical conductivity, Turbidity, Total dissolved solids (TDS), Total Hardness, Total Alkalinity, Calcium, Sulphate, Chloride, Magnesium, Iron, COD, DO, and BOD. The Water sample collected shows that the mean values of physicochemical parameters are in the range of WHO and BIS except for Hardness in summer (1,680 mg/L); monsoon (832.22 mg/L); winter (1,876.66 mg/L); spring (1,535.55 mg/L), TDS in summer (1,000.33 mg/L); monsoon (683.44 mg/L); winter (1,087.66 mg/L); spring (776.66 mg/L) and sulphate (927.22 mg/L); monsoon (446.77 mg/L); winter (925.77 mg/L); spring (944.88 mg/L) which indicate the bad quality of water. The WQI values were calculated for three locations at different weather conditions. WQI values in summer, winter and spring are 630.90, 279.61, 279.91 shows that river water is not suitable for drinking purpose whereas the WQI value in monsoon is 75.89 shows that water is fit for drinking purposes due to the dilution of river water. A moderate positive correlation was observed for turbidity with total hardness, iron, total alkalinity, and sulphate. Negative Correlation was observed with pH. Moderate Correlation was seen with TDS-EC (0.608), TDS-Alkalinity (0.7794), EC-Ca (0.723) and strong was observed for BOD-DO (0.941) and Ca-Mg (0.999). Principal Component Analysis revealed that five factors were significant (eigen value &gt; 0.5) with total variance of 39.43%–85.19% respectively. The ICP-MS study of water sample from point source indicate the presence of Ni2+, Cr6+, Co2+, Mn2+, Cu2+, Zn2+ ions at higher concentrations.