Characterization and antimicrobial properties of Matcha green tea

Matcha, made from the finely ground powder of green tea leaves, is used as a nutritious food ingredient because of its unique properties. In this study, Matcha was characterized using Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction analysis (XRD), energy-dispersive X-ray spectroscopy (EDX). Also, the antimicrobial properties of Matcha against 8 types of bacteria, 1 type of fungus, and 1 type of yeast were investigated. The results showed that Matcha has a completely amorphous structure and has a high content of carbon and oxygen. The results of antibacterial tests showed that Matcha has the ability to inhibit gram-positive and gram-negative bacteria as well as yeast, but has no effect on the fungus. Also, Matcha has a greater effect on gram-positive bacteria, which is due to the simple and reasonably porous cell wall of these bacteria. According to the results, the maximum and minimum inhibition zones created by Matcha belonged to Pseudomonas aeruginosa and Escherichia coli, respectively

Positive environmental effects of the coronavirus 2020 episode: a review

The outbreak of COVID-19 has made a global catastrophic situation that caused 1,039,406 deaths out of 35,347,404 infections, and it will also cause significant socio-economic losses with poverty increasing from 17.1 to 25.9%. Although the spreading rate of COVID-19 is very high on October 6, 2020, the death rate is still less than 2.94%. Nonetheless, this review article shows that the lockdown has induced numerous positive impacts on the environment and on energy consumption. For instance, the lockdown has decreased the electricity demand by 30% in Italy, India, Germany, and the USA, and by 12-20% in France, Germany, Spain, India, and the UK. Additionally, the expenditure of the fuel supply has been decreased by 4% in 2020 as compared to the previous years (2012-2019). In particular, The global demand for coal fuel has been reduced by 8% in March and April 2020 as compared to the same time in 2019. In terms of harmful emissions, the lockdowns reduced the emissions of nitrous oxides by 20-30% in China, Italy, France, Spain, and by 77.3% in São Paulo, Brazil. Similarly, the particulate matter level has been reduced from 5-15% in Western Europe, to 200% in New Delhi, India, which in turn has enhanced the air quality in a never-seen manner in recent times. In some places, such as New York, USA, CO2 emission was also reduced by 5-10%. The water quality, in several polluted areas, has also been remarkably enhanced, for example, the dissolved oxygen content in the Ganga River, India, has increased by about 80%. Traffic congestion has also been reduced worldwide, and in some areas, it has been reduced by 50%, such as New York and Los Angeles, USA. Overall, while the COVID-19 pandemic has shrinked the global economy by 13-32%, the pandemic has also clearly benefited to other sectors, which must be considered as the spotlight for the permanent revival of the global ecosystem. Keywords: Air pollution; COVID-19 benefits; Environmental regeneration; Renewable energy; Surface water; Traffic congestion

Chromium removal and water recycling from electroplating wastewater through direct osmosis: Modeling and optimization by response surface methodology

Background: Considering the carcinogenic effects of heavy metals, such as chromium, it is essential to remove these elements from water and wastewater. Direct osmosis is a new membrane technology, which can be a proper alternative to conventional chromium removal processes. Methods: The wastewater samples were collected from an electroplating unit, located in Alborz industrial city, Qazvin, Iran. Magnesium chloride was used as the draw solution, and a semipermeable membrane (Aquaporin) was used in this study. The experiments were designed, using response surface methodology (RSM) and central composite design (CCD) with draw solution concentration (0.5- 1.5 M), feed solution concentration (4-12 mg/L), and experiment time (30-90 minutes) as variable factors. The chromium concentration and water flux were also measured, based on atomic absorption spectrophotometry and water flux equation, respectively. Results: Direct osmosis was highly efficient in chromium removal and water recycling. Water flux and chromium removal efficiency were 15.6 LMH and 85.58%, respectively, under optimal conditions (draw solution = 1.27 mol/L, feed solution = 4 mg/L, and experiment time = 90 min). In terms of validity, the results predicted by the quadratic polynomial model were in good agreement with the responses reported in the laboratory. Conclusion: In direct osmosis, the use of magnesium chloride as the draw solution resulted in the acceptable chromium removal from electroplating wastewater. Using this method, chromium concentration in wastewater reduced to a level lower than the discharge standards, established by Iran’s Department of Environment. Keywords: Direct osmosis, Chromium removal, Electroplating, Optimizatio

Simultaneous removal of phenol and linear alkylbenzene sulfonate from automotive service station wastewater: Optimization of coupled electrochemical and physical processes

This work investigates the feasibility of the coupled electrochemical (electrocoagulation/flotation) and physical processes (sedimentation, sand filtration, and activated carbon) for the treatment of automotive service wastewater (ASWW). The impacts of critical parameters, viz. pH solution, reaction time and current intensity on linear alkylbenzene sulfonate (LAS), and phenol removal efficiencies as well as energy consumption and operating cost are studied. Central composite design results reveal that at the optimum conditions, LAS and phenol removal efficiencies, energy consumption and operating cost are obtained 96.7%, 87.65%, 15.99 Wh, 0.001 US$, respectively. This process reveals a feasible technology for phenol and LAS removal from ASW

A review on microplastics and nanoplastics in the environment: Their occurrence, exposure routes, toxic studies, and potential effects on human health

Microplastics (MPs) and nanoplastics (NPs) are emerging environmental pollutants, having a major ecotoxicological concern to humans and many other biotas, especially aquatic animals. The physical and chemical compositions of MPs majorly determine their ecotoxicological risks. However, comprehensive knowledge about the exposure routes and toxic effects of MPs/NPs on animals and human health is not fully known. Here this review focuses on the potential exposure routes, human health impacts, and toxicity response of MPs/NPs on human health, through reviewing the literature on studies conducted in different in vitro and in vivo experiments on organisms, human cells, and the human experimental exposure models. The current literature review has highlighted ingestion, inhalation, and dermal contacts as major exposure routes of MPs/NPs. Further, oxidative stress, cytotoxicity, DNA damage, inflammation, immune response, neurotoxicity, metabolic disruption, and ultimately affecting digestive systems, immunology, respiratory systems, reproductive systems, and nervous systems, as serious health consequences

Electrocoagulation-flotation treatment followed by sedimentation of carpet cleaning wastewater: optimization of key operating parameters via RSM-CCD

In the present study, the treatment of carpet cleaning wastewater was optimized for electrocoagulation- flotation (ECF) followed sedimentation. In the experimental study, an ECF reactor equipped with four monopolar, parallel-connected aluminum electrodes was utilized. For the optimization, the process variables were selected as methylene blue active substance (MBAS), chemical oxygen demand (COD), and turbidity removal efficiencies, along with the characterization of sludge settling volume at 60 min (SSV60). For this goal, response surface methodology (RSM) under central composite design (CCD) was employed to optimize the critical factors viz. pH (3.64–10.36), current intensity (0.66–2.34 A), and electrolysis time (9.55–110.45 min). RSM-CCD optimized these key factors to achieve maximum removal efficiencies and minimize SSV60. Based on the RSM-CCD prediction, the optimum operating conditions were as pH of 5.1, the current intensity of 2 A, and electrolysis time of 53.5 min, in which the obtained model predicted 83.56%, 82.54%, 88.14%, and 226.22 mL/L for MBAS, COD, turbidity, and SSV60. Correspondingly, the predictions were in agreement with the actual results (85.50%, 84.35%, 90.50%, and 240.17 mL/L, respectively). The operating cost in the optimal conditions was calculated as 0.673 USD/m3. The results of the study indicated that the electrocoagulation-flotation followed sedimentation was a cost-effective treatment process in removing target pollutants from the carpet cleaning wastewater

A critical review on the existing wastewater treatment methods in the COVID-19 era: What is the potential of advanced oxidation processes in combatting viral especially SARS-CoV-2?

The COVID-19 epidemic has put the risk of virus contamination in water bodies on the horizon of health authorities. Hence, finding effective ways to remove the virus, especially SARS-CoV-2, from wastewater treatment plants (WWTPs) has emerged as a hot issue in the last few years. Herein, this study first deals with the fate of SARS-CoV-2 genetic material in WWTPs, then critically reviews and compares different wastewater treatment methods for combatting COVID-19 as well as to increase the water quality. This critical review sheds light the efficiency of advanced oxidation processes (AOPs) to inactivate virus, specially SARS-CoV-2 RNA. Although several physicochemical treatment processes (e.g. activated sludge) are commonly used to eliminate pathogens, AOPs are the most versatile and effective virus inactivation methods. For instance, TiO2 is the most known and widely studied photo-catalyst innocuously utilized to degrade pollutants as well as to photo-induce bacterial and virus disinfection due to its high chemical resistance and efficient photo-activity. When ozone is dissolved in water and wastewater, it generates a wide spectrum of the reactive oxygen species (ROS), which are responsible to degrade materials in virus membranes resulting in destroying the cell wall. Furthermore, electrochemical advanced oxidation processes act through direct oxidation when pathogens react at the anode surface or by indirect oxidation through oxidizing species produced in the bulk solution. Consequently, they represent a feasible choice for the inactivation of a wide range of pathogens. Nonetheless, there are some challenges with AOPs which should be addressed for application at industrial-scale

Wastewater Based Epidemiology Perspective as a Faster Protocol for Detecting Coronavirus RNA in Human Populations: A Review with Specific Reference to SARS-CoV-2 Virus

Abstract: Wastewater-based epidemiology (WBE) has a long history of identifying a variety of viruses from poliovirus to coronaviruses, including novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The presence and detection of SARS-CoV-2 in human feces and its passage into the water bodies are significant public health challenges. Hence, the hot issue of WBE of SARS-CoV-2 in the coronavirus respiratory disease (COVID-19) pandemic is a matter of utmost importance (e.g., SARS-CoV-1). The present review discusses the background, state of the art, actual status, and prospects of WBE, as well as the detection and quantification protocols of SARS-CoV-2 in wastewater. The SARS-CoV-2 detection studies have been performed in different water matrixes such as influent and effluent of wastewater treatment plants, suburban pumping stations, hospital wastewater, and sewer networks around the globe except for Antarctica. The findings revealed that all WBE studies were in accordance with clinical and epidemiological data, which correlates the presence of SARS-CoV-2 ribonucleic acid (RNA) with the number of new daily positive cases officially reported. This last was confirmed via Reverse Transcriptase-quantitative Polymerase Chain Reaction (RT-qPCR) testing which unfortunately is not suitable for real-time surveillance. In addition, WBE concept may act as a faster protocol to alert the public health authorities to take administrative orders (possible re-emerging infections) due to the impracticality of testing all citizens in a short time with limited diagnostic facilities. A comprehensive and integrated review covering all steps starting from sampling to molecular detection of SARS-CoV-2 in wastewater has been made to guide for the development well-defined and reliable protocols

A State-of-the-Art Review on SARS-CoV-2 Virus Removal Using DifferentWastewater Treatment Strategies

In addition to the numerous health effects caused by the COVID-19 pandemic, the scientific community has considered other emerging effects such as water-related impacts worthy of deep investigation. In this regard, the transmission cycles of the SARS-CoV-2 virus from fecal, vomiting, and sputum routes to sewage have led health authorities to diagnose, prevent, and use novel wastewater treatment technologies. Once they enter the gastrointestinal canal of a healthy person, viral particles can infect via the nominal amount of Angiotensin-Converting Enzyme 2 (ACE2) present in alimentary canal epithelial cell surfaces and further infect lung, heart, kidney, and other organs. The current review highlights the detection, status, and fate of SARS-CoV-2 from sewage treatment facilities to water bodies. Besides, it addresses the potential wastewater treatment processes to cope with various viruses, especially SARS-CoV-2. Many processes can manage contaminated wastewater and solid wastes over the long term, including membrane technologies, disinfectants, UV-light and advanced oxidation methods like photocatalysis, ozonation, hydrogen peroxide, nanomaterials, and algae. Future work must focus on implementing the selected actions for the treatment of the wastewater released from the COVID-19 hospitals and self-quarantine centers to better regulate future waves of SARS-CoV-2

Evaluation of the performance of adsorption, electrochemical (ECF), and physical hybrid processes in carwash wastewater treatment

Background and aim: Treatment of the car wash wastewater (CWW) is important as a potential source of environmental health hazard due to the significant concentrations of contaminants such as detergents, oils-greases, phenol, organic materials. In the current study, chemical oxygen demand (COD), methylene blue active substances (MBAS), and turbidity removal efficiencies were conducted on CWW using adsorption, electrochemical (ECF), and physical hybrid processes. Material and Methods: In this research, the sample was first entered into the ECF reactor, then entered the retention tank after specific times and eventually passed through filtration. According to the standard methods, COD was measured by closed reflux colorimetric method, and turbidity was measured by Nephelometric method. MBAS was also quantified according to the method suggested by Chitikela et al. Experimental design for response surface methodology (RSM) was employed to create two series of 20 experimental runs using monopolar aluminium electrodes. It was optimized using the critical operational parameters such as applied current (1–2A), electrolysis time (30–90 min) and pH (5–9). Results: According to the RSM model, optimum conditions for pH, electrolysis time, and applied current were 7.67, 1.69 amps and 90 min, respectively, in which COD, turbidity and MBAS removal efficiencies were 94.5%, 95%, and 95.2%, respectively. The most predicted efficiency for the COD and turbidity removals were 100%, 96.69%, and 97.9%, respectively. Electric energy consumption and operating costs were found to be 4.2 kWh/m3 and 4206 Rials/m3 (0.056 $/m3), respectively. Conclusion: The hybrid treatment process used in this study seems to be an efficient and cost-effective method compared to existing conventional treatment methods used in removing pollutants from carwash wastewater. Therefore, this method can be used removing pollutants with high concentrations from car wash industry wastewater and in wastewater reclamation. More research is also suggested on other pollutants in carwash wastewater for future studies. Keywords: Carwash wastewater, Adsorption, Electrochemical, Physical, Hybrid treatment