In this study, a titanium plate was impregnated with SnO₂ and Sb (Ti/SnO₂–Sb₂O₄) for the electrocatalytic removal of phenol from wastewater, and the chemical degradation pathway was presented. The effects of various parameters such as pH, current density, supporting electrolyte, and initial phenol concentration were studied. At optimum conditions, it was found that phenol was quickly oxidized into benzoquinone because of the formation of various strong radicals during electrolysis by the Ti/SnO₂–Sb₂O₄ anode from 100 to <1 mg/L over 1 h. The results of GC/MS analysis showed the presence of some esters of organic acid such as oxalic acid and formic acid. HPLC analysis showed only trace amounts of benzoquinone remaining in the solution. The efficiency of TOC removal at the Ti/SnO₂–Sb₂O₄ anode surface showed a degradation rate of 49 % over 2 h. Results showed that the molecular oxygen potential at the electrode was 1.7 V. The phenol removal mechanism at the surface of the Ti/SnO₂–Sb₂O₄ anode was influenced by the pH. Under acidic conditions, the mechanism of electron transfer occurred directly, whereas under alkaline conditions, the mechanism can be indirect. This research shows that the proposed electrolyte can significantly influence the efficiency of phenol removal. It can be concluded that the treatment using an appropriate Ti/SnO₂–Sb₂O₄ electrode surface can result in the rapid oxidation of organic pollutants.

This study investigated the degradation of sulfonamide antibiotics (SAs) and microbial community changes in sludge-amended soil. In batch experiments, SA degradation was enhanced by addition of spent mushroom compost (SMC), SMC extract, and extract-containing microcapsule, with SMC showing higher SA degradation rate than the other additives in soil-sludge mixtures. In bioreactor experiments, the degradation of SAs in soil-sludge mixtures was in the order of sulfamethoxazole > sulfadimethoxine > sulfamethazine during four times of SA addition. SA removal was higher in soil-sludge mixtures than in soil alone. The bacterial composition differed in soil-sludge mixtures with and without SMC. In total, 44 differentially distributed bacterial genera were identified from different experimental settings and stages. Four bacterial genera, Acinetobacter, Alcaligenes, Brevundimonas, and Pseudomonas, were previously found involved in SA degradation, and 20 of the 44 bacterial genera were previously found in aromatic hydrocarbon degradation. Therefore, these bacteria have high potential to be SA degradation bacteria in this study.

The study aimed to determine the fungal diversity in clinical waste samples from a healthcare facility in Penang Malaysia. Different fungi species were detected in 83.75 % of the 92 clinical waste samples that were screened from different sections of the healthcare facility. One hundred fifty fungal isolates comprising of 8 genera and 36 species were obtained. They were purified by using single spore isolation technique. Subsequently, the isolates were identified by phenotypic method based on morphological and culture characteristics on different culture media. Among all fungal isolates, Aspergillus spp. in section Nigri 10.2 %, Aspergillus niger 9.5 %, Aspergillus fumigatus 8.8 %, Penicillium. simplicissium 8 %, Aspergillus tubingensis 7.3 %, Aspergillus terreus var. terreus 6.6 %, Penicillium waksmanii 5.9 % and Curvularia lunata 6.5 % were the most frequent. Among five sections of the Wellness Centre, the clinical wastes collected from the diagnostic labs of haematology section had the highest numbers of fungal species (29 species). Glove wastes had the highest numbers of fungal species (19 species) among 17 types of clinical wastes screened. Among all fungal species, Aspergillus spp. exhibited higher growth at 37 °C than at 28 °C, indicating the potential of these opportunistic fungi to cause diseases in human. These results indicated the potential of hospital wastes as reservoirs for fungal species.

The issues of energy security, dwindling supply and inflating price of fossil fuel have shifted the global focus towards fuel of renewable origin. Biodiesel, having renewable origin, has exhibited great potential as substitute for fossil fuels. The most common route of biodiesel production is through transesterification of vegetable oil in presence of homogeneous acid or base or solid oxide catalyst. But, the economics of biodiesel is not competitive with respect to fossil fuel due to high cost of production. The vegetable oil waste is a potential alternative for biodiesel production, particularly when disposal of used vegetable oil has been restricted in several countries. The present study evaluates the efficacy of a low-cost solid oxide catalyst derived from eggshell (a food waste) in transesterification of vegetable oil and simulated waste vegetable oil (SWVO). The impact of thermal treatment of vegetable oil (to simulate frying operation) on transesterification using eggshell-derived solid oxide catalyst (ESSO catalyst) was also evaluated along with the effect of varying reaction parameters. The study reported that around 90 % biodiesel yield was obtained with vegetable oil at methanol/oil molar ratio of 18:1 in 3 h reaction time using 10 % ESSO catalyst. The biodiesel produced with ESSO catalyst from SWVO, thermally treated at 150 °C for 24 h, was found to conform with the biodiesel standard, but the yield was 5 % lower compared to that of the untreated oil. The utilization of waste vegetable oil along with waste eggshell as catalyst is significant for improving the overall economics of the biodiesel in the current market. The utilization of waste for societal benefit with the essence of sustainable development is the novelty of this work.

A mixture of pig manure and maize straw was vermicomposted with Eisenia fetida or naturally composted for 60 days; basic parameters, heavy metal variation, dissolved organic matter (DOM) content, and its characterization were determined, aiming to explore different dynamics of DOM characterization and heavy metal variation during composting or vermicomposting. The results showed that vermicomposting led to higher pH, TC, and available P but lower EC, TN, available N, and available K in the substrate residues compared with natural composting; the total or available Cu/Zn content in the substrate residues similarly increased after composting or vermicomposting, but Cu was easily enriched in earthworm bodies and its intestinal vermicompost while vermicomposting enhanced the formation of dissolved Zn in DOM; moreover, much more fulvic and humic acid-like materials and much greater aromaticity were exhibited in DOM obtained from vermicomposting residues compared with DOM from composting residues, which may contribute to the variations of Cu/Zn enrichment in earthworms and its migration to the vermicomposting residues or its DOM.

The water-soluble polyacrylamide (PAM) can accumulate in ecosystems and cause serious environmental pollution. Biological approach achieves poor PAM degradation efficiency, due to the extreme resistance of PAM to the microbial metabolism. In the present work, the potential of bioelectrochemical system (BES) as an effective tool to degrade the PAM is adequately evaluated. The closed-circuit operation of BES obtains COD removal efficiencies of 29.2 and 33.6 % for the PAM and polyacrylic acid (PAA), respectively. In comparison, 4.3 and 2.7 % of COD are removed after the PAM and PAA are treated in the open-circuit BES, and 7.3 and 6.6 % are removed in the aerobic BES. These results suggest the bioelectricity generation is crucial to trigger the activity of bioanode for the effective degradation of PAM. Bioelectricity generation not only favors the decomposition of carbon backbone but also facilitates the hydrolysis of amide group in the side-chain of PAM. Microbial attack on the carbon backbone of PAM is proposed to initiate at the head-to-head linkage, resulting in the formation of ether bond within the shortened carbon chain. The Ignavibacterium sp. and phenotypically uncharacterized bacteria are classified as the dominant species on the anode of PAM-fed BES.

Lead (Pb) intoxication is a worldwide health problem which frequently affects the liver. This study was carried out to investigate the potential protective effect of thymoquinone (TQ), the major active ingredient of volatile oil of Nigella sativa seeds, against Pb-induced liver damage. Adult male rats were randomized into four groups: Control group received no treatment, Pb group was exposed to 2000 ppm Pb acetate in drinking water, Pb-TQ group was cotreated with Pb plus TQ (5 mg/kg/day, per orally), and TQ group receiving only TQ. All treatments were applied for 5 weeks. Results indicated that Pb exposure increased hepatic Pb content, damaged hepatic histological structure (necrotic foci, hepatic strands disorganization, hypertrophied hepatocytes, cytoplasmic vacuolization, cytoplasmic loss, chromatin condensation, mononuclear cell infiltration, congestion, centrilobular swelling), and changed liver function investigated by plasma biochemical parameters (AST, ALT, ALP, γ-GT, LDH). Pb treatment also decreased total antioxidant status level and increased lipid peroxidation in the liver. Supplementation with TQ remarkably improved the Pb-induced adverse effects without significantly reducing the metal accumulation in the liver. In conclusion, our results indicate, for the first time, a protective effect of TQ against Pb-induced hepatotoxicity and suggest that this component might be clinically useful in Pb intoxication.

The month-to-month variability of biomass and CaCO₃ precipitation by dense charophyte beds was studied in a shallow Chara-lake at two depths, 1 and 3 m. Charophyte dry weights (d.w.), the percentage contribution of calcium carbonate to the dry weight and the precipitation of CaCO₃ per 1 m² were analysed from May to October 2011. Physical-chemical parameters of water were also measured for the same sample locations. The mean dry weight and calcium carbonate precipitation were significantly higher at 1 m than at 3 m. The highest measured charophyte dry weight (exceeding 2000 g m⁻²) was noted at 1 m depth in September, and the highest CaCO₃ content in the d.w. (exceeding 80 % of d.w.) was observed at 3 m depth in August. The highest CaCO₃ precipitation per 1 m² exceeded 1695 g at 1 m depth in August. Significant differences in photosynthetically active radiation (PAR) were found between 1 and 3 m depths; there were no significant differences between depths for other water properties. At both sampling depths, there were distinct correlations between the d.w., CaCO₃ content and precipitation and water properties. In addition to PAR, the water temperature and magnesium and calcium ion concentrations were among the most significant determinants of CaCO₃ content and d.w. The results show that light availability seems to be the major factor in determining charophyte biomass in a typical, undisturbed Chara-lake. The study results are discussed in light of the role of charophyte vegetation in whole ecosystem functioning, with a particular focus on sedimentary processes and the biogeochemical cycle within the littoral zone.

Microplastics are found in marine and freshwater environments; however, their specific sources are not yet well understood. Understanding sources will be of key importance in efforts to reduce emissions into the environment. We examined the emissions of microfibers from domestic washing of a new microfiber polyester fleece textile. Analyzing released fibers collected with a 200 μm filter during 10 mild, successive washing cycles showed that emission initially decreased and then stabilized at approx. 0.0012 wt%. This value is our estimation for the long-term release of fibers during each washing. Use of detergent and softener did not significantly influence emission. Release of fibers during tumble drying was approx. 3.5 times higher than during washing.

The content and bioaccumulation of trace (Ag, Se, As) and major elements (Ca, Mg, Na and K) in wild edible mushroom Macrolepiota procera and its corresponding soil substrates, collected from five sites in the Rasina region in central Serbia, were investigated. The content of Ag, As and Se was determined by inductively coupled plasma mass spectrometer (ICP-MS) while the amount of Ca, Mg, Na and K was determined by inductively coupled plasma optical emission spectrometer (ICP-OES). The concentrations of major elements in the mushrooms were at typical levels. As far as trace elements are concerned, M. procera bioaccumulates silver although all samples were collected from unpolluted sites. It was found that the content of Ag depended on the geographical origin and the density of fruiting body on the certain site. Principal component analysis distinguished the mushroom samples from different geographical areas and revealed the influence of soil composition on metal content in fruiting bodies. Also, a linear regression correlation test was performed to investigate correlations between Ag, Cd, Se, Pb and As in caps and stipes at different geographic sites separately. In addition, our results indicated that M. procera could serve as a good dietary source of Mg, K and Se. The content of Ag and As was low, so it could not pose a health risk for consumers.