Exploring possible strategies for treating SARS-CoV-2 in sewage wastewater: A review of current research and future directions.

The advent of acute respiratory coronavirus disease (COVID-19) is convoyed by the shedding of the virus in stool. Although inhalation from person-to-person and aerosol/droplet transmission are the main modes of SARS-Coronavirus-2 (SARS-CoV-2) transmission, currently available evidence indicates the presence of viral RNA in the sewerage wastewater, which highlights the need for more effective corona virus treatment options. In the existing COVID-19 pandemic, a substantial percentage of cases shed SARS-CoV-2 viral RNA in their faeces. Hence the treating this sewerage wastewater with proper surveillance is essential to contain this deadly pathogen from further transmission. Since, the viral disinfectants will not be very effective on sewerage waste as organic matter, and suspended solids in water can protect viruses that adsorb to these particles. More effective methods and measures are needed to prevent this virus from spreading. This review will explore some potential methods to treat the SARS-CoV-2 infected sewerage wastewater, current research and future directions.

Biologia Futura: treatment of wastewater and water using tannin-based coagulants.

Industrialization and urbanization are mainly responsible for environmental pollution generating enormous amount of wastewater which needs to be treated. Wastewaters from various sources are toxic to humans and livestock, as well as posing environmental risks. Various treatment approaches have been used for the elimination of contaminants from water and wastewater. Coagulation/flocculation processes are the most commonly used techniques in water treatment for improving the condition of turbid water and removing suspended particles by destabilization and the creation of larger, heavier flocs that aid in sedimentation. Flocculants, both organic and inorganic, have long been used in wastewater treatment. The use of natural coagulants/flocculants for water and wastewater treatment has become essential due to the health risks associated with chemical flocculants. Tannin, a natural coagulant, has been suggested as substitute of chemical coagulants. Tannins are present in the leaves, fruits, barks, roots, and wood of trees as a secondary metabolite. Tannin-based coagulants derived from a variety of plant sources have been successfully used in the treatment of water and wastewater. This review summarises the current status and strategies on applications of tannin-based coagulants exploiting the eco-friendly green materials in water and wastewater remediation for the sake of pollution free environment.

Wastewater treatment using plant-derived bioflocculants: green chemistry approach for safe environment.

The rapid expansion of global trade and human activities has resulted in a massive increase in wastewater pollution into the atmosphere. Suspended solids, organic and inorganic particles, dissolved solids, heavy metals, dyes, and other impurities contained in wastewater from various sources are toxic to the atmosphere and pose serious health risks to humans and animals. Coagulation-flocculation technology is commonly used in wastewater treatment to remove cell debris, colloids, and contaminants in a comfortable and effective manner. Flocculants, both organic and inorganic, have long been used in wastewater treatment. However, because of their low performance, non-biodegradability, and associated health risks, their use has been limited. The use of eco-friendly bioflocculants in wastewater treatment has become essential due to the health implications of chemical flocculants. Because of their availability, biodegradability, and protection, plant-derived coagulants/flocculants and plant-based grafted bioflocculants have recently made significant progress in wastewater treatment. This study will undoubtedly provide a clearer understanding of the current state, challenges, and solutions for bioflocculation in wastewater remediation using green materials for the sake of a cleaner climate.

Green Formulation of Microbial Biopolyesteric Nanocarriers Toward In Vitro Drug Delivery and Its Characterization.

In the present study, formulation and characterization of microbial biopolyesteric nanocarrier (MBPNc) was reported for in vitro controlled release of the drugs, viz., amoxicillin and levofloxacin. The synthesis of microbial biopolyester, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nanoparticle was done by a triple emulsion method and loaded with amoxicillin and levofloxacin to improve its curative bioavailability. The synthesized MBPNc was found to be spherical in shape with a size range of 50-100 nm which was confirmed through Transmission Electron Microscopy (TEM) analysis. The surface topology and physicochemical characteristics were analyzed by Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), and X-Ray Diffraction (XRD) spectroscopy. The cell viability % of MBPNc, amoxicillin-loaded MBPNc, and levofloxacin-loaded MBPNc on HEK293 cells at a concentration of 400 µg/ml were found to be 93.43 ± 0.66%, 92.29 ± 0.61%, and 91.53 ± 0.46%, respectively, which confirmed that MBPNc is biocompatible and can be used for biomedical applications without any cytotoxic effect. A significant decrease in the bacterial survival ratio (%) and increase in the zone of inhibition were observed on increasing the concentration of drug-loaded MBPNc against E. coli (ATCC®8739™) and S. aureus (ATCC®23,235™). The in vitro drug delivery study showed controlled release of amoxicillin (99.85 ± 0.15%) and levofloxacin (99.73 ± 0.24%) up to 22 h.

Application of Aloe vera mucilage as bioflocculant for the treatment of textile wastewater: process optimization.

Aloe vera is an important commodity plant which has been traditionally used for the treatment of various diseases. This study investigated the use of extracted bioflocculant from Aloe vera for the treatment of textile wastewater. The bioflocculant was extracted, purified and characterized using GC-MS, FTIR, SEM, AFM, EDX and XRD analysis. It was mainly composed of carbohydrate (19.5%) and protein (6.0%). Box-Behnken design (BBD), using 3 level-3 variables, was employed to enhance the decolorization process by optimizing the effect of various factors. A significant enhancement from 62.50 ± 0.1 to 82.01 ± 0.8% in decolorization of wastewater was observed under optimized conditions viz. bioflocculant dosage (60 mg/L), pH (5.0) and contact time (180 min). A quadratic polynomial model was adequate beside the actual statistics at an R2 value of 0.99 for the response decolorization % and was in good agreement with the predicted value (82.01 ± 0.1%) obtained by the RSM model. The results of the present investigation demonstrated that Aloe vera mucilage can serve as a promising bioflocculant with high removal efficiency for solids, colour and dye from wastewater. To the best of our information, this is the first report on the use of Aloe vera mucilage as a natural bioflocculant for the treatment of dye-bearing wastewater.

Fabrication and characterization of biodegradable PHBV/SiO2 nanocomposite for thermo-mechanical and antibacterial applications in food packaging.

In the present study, biogenic silica nanoparticles (bSNPs) were synthesized from groundnut shells, and thoroughly characterized to understand its phase, and microstructure properties. The biopolymer was synthesized from yeast Wickerhamomyces anomalus and identified as Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) by GC-MS and NMR analysis. The bSNPs were reinforced to fabricate PHBV/SiO2 nanocomposites via solution casting technique. The fabricated PHBV/SiO2 nanocomposites revealed intercalated hybrid interaction between the bSNPs and PHBV matrix through XRD analysis. PHBV/SiO2 nanocomposites showed significant improvement in physical, chemical, thermo-mechanical and biodegradation properties as compared to the bare PHBV. The cell viability study revealed excellent biocompatibility against L929 mouse fibroblast cells. The antibacterial activity of PHBV/SiO2 nanocomposites was found to be progressively improved upon increasing bSNPs concentration against E. coli and S. aureus.

Enhanced degradation of indeno(1,2,3-cd)pyrene using Candida tropicalis NN4 in presence of iron nanoparticles and produced biosurfactant: a statistical approach.

Seven yeast isolates were screened for the remediation of indeno(1,2,3-cd)pyrene (InP) using biosynthesized iron nanoparticles and produced biosurfactant in growth medium. Four yeast isolates showed positive response to produce biosurfactant which was confirmed by drop collapse test, emulsification index, methylene blue agar plate method, oil displacement test and lipase activity. The yeast strain showing maximum potential for InP degradation and biosurfactant production was identified as Candida tropicalis NN4. The produced biosurfactant was characterized as sophorolipid type through TLC and FTIR analysis. Iron nanoparticles were biosynthesized using mint leaf extract and characterized by various instrumental analysis. Response surface methodology (RSM), three-level five-variable Box-Behnken design (BBD) was employed to optimize the factors, viz., pH (7), temperature (30 °C), salt concentration (1.5 g L-1), incubation time (15 days) and iron nanoparticles concentration (0.02 g L-1) for maximum InP degradation (90.68 ± 0.7%) using C. tropicalis NN4. It was well in close agreement with the predicted value which was obtained by RSM model (90.68 ± 0.4%) indicating the validity of the model. InP degradation was confirmed through FTIR and GC-MS analysis. A kinetic study demonstrated that InP degradation fitted first-order kinetic model. This is the first report on yeast-mediated nanobioremediation of InP and optimization of the whole process using RSM.

A Statistical approach to optimize the production of Polyhydroxyalkanoates from Wickerhamomyces anomalus VIT-NN01 using Response Surface Methodology.

Polyhydroxyalkanoates (PHAs) are three-level group of biodegradable polymers and attractive substitutes over conventional plastics to avoid the pollution problems. The yeast strain isolated from sugarcane juice, identified as Wickerhamomyces anomalus VIT-NN01, was used for the production of polyhydroxyalkanoates (PHA). Response surface methodology (RSM), three-level six variables Box-Behnken design (BBD), was employed to optimize the factors such as pH 8.0, temperature 37°C, sugarcane molasses (35g/L) supplemented with co-substrate palm oil (0.5%),corn steep liquor (2%) after a period of 96h of incubation for the maximum yield (19.50±0.3g/L) of PHA. It was well in close agreement with the predicted value obtained by RSM model yield (19.55±0.1g/L).Characterization of the extracted polymer was done using FTIR, GC-MS, XRD, TGA and AFM analysis. NMR spectroscopic analysis revealed that the biopolymer was poly (3-hydroxybutyrate-co-3-hydroxyvalerate), copolymer of PHA. This is the first report on optimization of PHA production using yeast strain isolated from natural sources.

Evaluation of HDPE and LDPE degradation by fungus, implemented by statistical optimization.

Plastic in any form is a nuisance to the well-being of the environment. The 'pestilence' caused by it is mainly due to its non-degradable nature. With the industrial boom and the population explosion, the usage of plastic products has increased. A steady increase has been observed in the use of plastic products, and this has accelerated the pollution. Several attempts have been made to curb the problem at large by resorting to both chemical and biological methods. Chemical methods have only resulted in furthering the pollution by releasing toxic gases into the atmosphere; whereas; biological methods have been found to be eco-friendly however they are not cost effective. This paves the way for the current study where fungal isolates have been used to degrade polyethylene sheets (HDPE, LDPE). Two potential fungal strains, namely, Penicillium oxalicum NS4 (KU559906) and Penicillium chrysogenum NS10 (KU559907) had been isolated and identified to have plastic degrading abilities. Further, the growth medium for the strains was optimized with the help of RSM. The plastic sheets were subjected to treatment with microbial culture for 90 days. The extent of degradation was analyzed by, FE-SEM, AFM and FTIR. Morphological changes in the plastic sheet were determined.

Facets of Nanotechnology as Seen in Food Processing, Packaging, and Preservation Industry.

Nanotechnology has proven its competence in almost all possible fields we are aware of. However, today nanotechnology has evolved in true sense by contributing to a very large extent to the food industry. With the growing number of mouths to feed, production of food is not adequate. It has to be preserved in order to reach to the masses on a global scale. Nanotechnology made the idea a reality by increasing the shelf life of different kinds of food materials. It is not an entirely full-proof measure; however it has brought down the extent of wastage of food due to microbial infestation. Not only fresh food but also healthier food is being designed with the help of nano-delivery systems which act as a carrier for the food supplements. There are regulations to follow however as several of them pose serious threats to the wellbeing of the population. In coming days, newer modes of safeguarding food are going to be developed with the help of nanotechnology. In this paper, an overview has been given of the different methods of food processing, packaging, and preservation techniques and the role nanotechnology plays in the food processing, packaging, and preservation industry.

Evolution of bacterial and fungal growth media.

Microbial media has undergone several changes since its inception but some key challenges remain. In recent years, there has been exploration of several alternative nutrient sources, both to cater to the specificity in requirement of growth of "fussy microorganisms" and also to reduce costs for large-scale fermentation that is required for biotechnology. Our mini-review explores these developments and also points at lacunas in the present areas of exploration, such as a lack of concerted effort in pH and osmolarity regulation. We hope that our commentary provides direction for future research in microbial media.