17α-methyltestosterone (MT) is an exogenous anabolic steroid hormone used widely in aquafarming. This study aimed to emphasize the environmental hazards of MT originated from a continuously operating masculinization pond with an intensive water recirculation system in Samut Prakan, Thailand. Risk quotient (RQ) and concentration factor (CF) were used to examine the ecological risk of MT in the pond environment. The results revealed relatively high MT concentrations in the water and sediments. These findings concurred the benefit of masculinization ponds with a water recirculation system in the way that it can effectively save the water and reduce the MT dosage that needs to be added into the feed. However, this could bring serious environmental concerns since releasing water containing MT residues and androgenic active metabolites through water overflowing from the masculinization pond to the environment during the wet season is inevitable. This is the first report indicating that CF relates to the androgenic potential activity and can be used to explain the ecological risk of MT contaminated water discharged from a full water recirculating earthen masculinization pond. This study provides important information indicating that CF values in a range of 7 to 16 are high enough to cause adversely affect the reproductive performance of tested fish (i.e., Probarbus jullieni, Barbonymus gonionotus, and Anabas testudineus).

Fish processing produces large amounts of fish waste. Instead of disposing of it, it is wiser to recover the valuable resource for high-value-added products. Our study proposed a process using carbon dioxide-acidified water as a green solvent under supercritical conditions to successfully recover collagen/gelatin from the skin and bone of striped catfish. The optimum extraction conditions were obtained at 75 bar, 37 °C, and 24 h. The yields from the dry skin and bone mass were around 37% and 8%, respectively. The extracted products were characterized by Fourier-transformed infrared spectroscopy to study the functional groups, scanning electron microscopy to evaluate the morphology, sodium dodecyl-sulfate polyacrylamide gel electrophoresis to study the protein pattern, UV–vis analysis to measure the absorption peak, and thermal gravimetric analysis to determine the denaturation temperature. The results show the viability of the proposed method on an industrial scale. The characteristics of the extracted product show promising results and potential for being developed further in many applications such as biomaterial engineering in healthcare or natural polymer-based absorbent material for efficient removal of heavy metals from water and wastewater.

Molecularly imprinted polymers@ethylenediamine-modified carbon dots grafted on cotton fabrics (MIPs@EDA-CDs/CF) and smartphone-based fluorescence image analysis were proposed and used for the first time for the detection of 17 α-methyltestosterone (MT). The EDA-CDs were synthesized and grafted on cotton fabric before coating with the MIPs. The MIPs were synthesized using the MT as a template molecule, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linker, and azobisisobutyronitrile (AIBN) as an initiator. The MIPs@EDA-CDs/CF were characterized using FTIR, SEM-EDS, and RGB fluorescence imaging. The fluorescence images were also taken using a smartphone and the ImageJ program was used for RGB measurement. The Δ red intensity was linearly proportional to MT concentration in the range of 100 to 1000 μg/L (R² = 0.999) with a detection limit of 44.4 μg/L and quantification limit of 134 μg/L. The MIPs@EDA-CDs/CF could be stored at 4 °C for a few weeks and could be reused twice. The proposed method could apply for the specific determination of MT in water and sediment samples along with satisfactory recoveries of 96–104% and an acceptable relative standard deviation of 1–6% at the ppb level.

Coffee silverskin (CS) is the only byproduct of the roasting process for coffee beans and is rich in phenolic compounds with various bioactivities. This study proposes a valorization option for bioactive compounds (T-CQA) based on a subcritical water extraction (SWE) technique, which is known for its high efficiency and feasibility for use on an industrial scale. The use of water as a sole solvent requires a minimum number of cleaning steps and renders the extract safe for further applications, such as in either the cosmetic or food industry. Response surface methodology with a Box–Behnken design is effectively used to optimize and explain the individual and interactive process variables (i.e., extraction temperature, extraction time, and solid–liquid ratio) on the T-CQA content obtained from coffee silverskin by the SWE technique. The final model exhibits a precise prediction of the experimental data obtained for the maximum T-CQA content. Under the optimum conditions, the CS extract is found to contain a higher content of T-CQA and TPC than that reported previously. For antioxidant activity, up to 26.12 ± 3.27 mg Trolox equivalent/g CS is obtained.

Type 1 pseudo second-order: $\frac{t}{q}=\frac{1}{k_2\hspace{0.17em}{q}_e^2}+\left(\frac{1}{q_t}\right)t$

Metal contamination from farming, inadequate wastewater treatment, and poor disposal of municipal garbage are major threats to public health. This research aimed to (1) assess the extent of heavy metal contamination in sediment samples, (2) describe the distribution of heavy metals by locating likely pollution sources using a positive matrix factorization (PMF) model, and (3) quantify the potential ecological consequences associated with these metals at six different places around the Chan Thnal Reservoir. The findings indicated steady degradation and suggested moderate to high metal contamination. Fe > Zn > Cr > Cu > Pb > Co > As > Mn > Cd was the trend of metal concentrations in the sediment. Various soil pollution indices showed that most of the studied sediment samples were clean, moderately clean, or slightly contaminated. However, Co and Cd reached high-risk conditions posing a severe problem to the local population living in and around the Chan Thnal Reservoir. Principal component analysis (PCA) was used to estimate primary factors in PMF analysis. It was found that the contamination of As, Cu, Zn, Cd, and Pb originated from agricultural and traffic vehicle sources; however, Zn, Fe, Mn, Cr, and Cu were derived from natural sources (e.g., atmospheric deposition and compost amendment). Furthermore, Fe, Cd, Mn, Co, Pb, and Cr were generated from urban and industrial sources (metal coatings, plastic burning, wastewater irrigation, and sewage sludge). Accordingly, this research improves our knowledge of the prevalence of heavy metal pollution in agroecosystems, which may be used to foresee and mitigate the risks of heavy metal exposure to humans and other organisms.