The implementation of processes imitating natural systems might be necessary to ensure sustainability. Titaniumdioxide (TiO2) nanoparticles were synthesized in an eco-friendly manner using citrus limon leaf extract as bothareducing and stabilizing agent. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR) and energy-dispersive spectroscopy (EDS) were usedtocharacterize the synthesized nanoparticles. The crystallized material was in the anatase phase, was quasi-spherical, with slight agglomeration and had distinct Ti–O–Ti vibration bands. The synthesized TiO2 nanoparticles wereassessed for their photocatalytic activity by UV light-induced methylene blue (MB) degradation. The effects of catalyst loading (0.1–0.3 g L -1), initial dye concentration (10–50 ppm) and irradiation time (5–180 min) wereexamined. With the optimum conditions, about 85.36% MB removal was accomplished. The degradation processwas a pseudo-first-order reaction with the rate constant of 0.0124 min -1 , (R 2= 0.9839). The response surfacemethodology (RSM) using central composite design (CCD) generated a statistically significant quadratic model witha high value of R 2 (99.69%) and a low p-value (< 0.0001), showing good predictive capacity. The study has shownthe potential of plant-mediated TiO2 nanoparticles as a simple, environmentally friendly and promisingphotocatalyst for treating the wastewater containing dyes. The integration of bio-derived synthesis withphotocatalytic wastewater treatment adds to the avenues for more sustainable environmental remediation, whilepaving the way for optimization and scaling up of plant-assisted nanomaterial synthesis and photocatalytic processes. The study is closely related with SDG-6 (Clean Water and Sanitation) because of its concern with the target of removing the organic dye pollutants from wastewater. In addition, the study is related to the scope of the Special Issue, investigating sustainable materials, eco-friendly synthesis strategies, and cutting-edge photocatalyticprocesses for environmental cleanup.
Shark liver oil is a valuable source of bioactive lipids, particularly monounsaturated fatty acids (MUFAs) (MUFAs) and polyunsaturated fatty acids (PUFAs), which are highly susceptible to oxidative degradation during processing. This study aimed to evaluate the effects of sunlight and oven-heating extraction methods on the chemical characteristics and fatty acid composition of black rough shark (Carrhigaelus barbifer) liver oil. Liver samples wereextracted using sunlight exposure and oven heating at 60 and 70 °C. The extracted oils were analyzed for yieldandmoisture content, while their chemical profiles were characterized using Fourier Transform Infrared Spectroscopy(FTIR) and Gas Chromatography–Mass Spectrometry (GC–MS). FTIR analysis showed identical characteristicabsorption bands at 2922, 1744, 1446, 1379, and 834 cm-1 in all samples, indicating the preservation of triglyceridestructures and unsaturated fatty acids regardless of extraction method. GC–MS results revealed that the oils werepredominantly composed of unsaturated fatty acids. Sunlight-heated oil contained higher levels of methyl nervonate(61.58%) and total MUFAs (61.71%), whereas oven-heated oil exhibited higher docosahexaenoic acid (DHA) content (45.81%) and total PUFAs (47.61%). These findings demonstrate that both extraction methods effectivelymaintain the chemical integrity and bioactive lipid composition of shark liver oil. Sunlight heating represents asimple, low-cost, and sustainable alternative to conventional oven extraction without compromising the fundamental chemical properties of the oil. Further studies involving oxidative stability parameters are recommendedtocomprehensively assess oil quality during processing and storage.
Molecular docking was conducted on a set of twenty compounds (SB1 to SB20) targeting the Kelch domainof keap1 (PDB: 8A46). Among the docked compounds, SB1 to SB5 showed strong binding affinity, whereas SB6toSB20 exhibited moderate affinity. A series of five novel bis-phenolate Zn(II) Schiff bases (SB1-SB5) weresynthesised by condensing vanillin with structurally diverse aromatic amines, followed by complexation with Zn(II) using microwave irradiation. Compounds were analysed using spectroscopic studies and LC-HRMS. Antioxidant potential was screened by the DPPH assay at 5–320 µg/mL, resulting in IC50 values between 13.85 and 26.70µg/mL. Notably, compounds SB1, SB2 and SB4 demonstrated strong free radical scavenging capabilities, whereasSB3 and SB5 exhibited moderate activity in comparison to the reference standard, ascorbic acid.
The growing demand for environmentally sustainable nanomaterials has increased interest in biological nanoparticlesynthesis. This study compared the green synthesis and physicochemical properties of copper and magnesiumnanoparticles produced using Aspergillus oryzae cell culture and Zingiber of icinale (ginger) extract as biological reducing and stabilising agents. Nanoparticle formation was initially indicated by colour changes and subsequentlyconfirmed through scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transforminfrared (FTIR) spectroscopy, and ultraviolet–visible (UV–Vis) spectroscopy. UV–Vis analysis showed maximumabsorption at 550and 400 nm for A. oryzae-mediated copper and magnesium nanoparticles, respectively, and at 500 and 400 nmfor ginger-mediated copper and magnesium nanoparticles. FTIR analysis revealed hydroxyl, carbonyl, amine, methoxy, aldehyde, and aromatic groups, suggesting their involvement in metal-ion reduction and nanoparticle stabilisation. XRD confirmed crystallinity, with average crystallite sizes of 7.24 and 7.43 nm for fungal-derived copper andmagnesium nanoparticles, respectively, compared with 59.4 and 23.0 nm for the corresponding ginger-derivednanoparticles. SEM revealed predominantly irregular particles measuring 50–83.5 nm, with fungal-derivedmagnesium nanoparticles showing the smallest average size. Both biological systems successfully produced stablenanoparticles, although A. oryzae provided greater control over crystallite and particle size. Green fungal and plant- mediated synthesis therefore offers a sustainable approach for potential biomedical, agricultural, and environmental applications.
An innovative and cost-effective method has been devised using high-performance liquid chromatographywithPDA detection for the assessment of Azathioprine and its related impurities (1-methyl-4-nitro-1H-imidazol-5-amineand 7H-purine-6-thiol). Validation was performed in accordance with ICH guidelines, confirming that the methodislinear, accurate, precise, and robust. The established method is suitable for routine quality control analysis of Azathioprine in pharmaceutical formulations (SDG-3). The chromatographic separations were conducted ona(150×4.6 mm), 3.5 µm Waters Symmetry C18 column, utilizing a mobile phase of 0.1% orthophosphoric acid buffer and Acetonitrile in a 30:70 ratio at a flow rate of 1.0 mL/min. Azathioprine and its two impurities were eluted inlessthan 10 minutes. The column oven temperature was maintained at 30° C, the sample temperature was kept at 20° C, and a detector wavelength of 235 nm was used. The method was validated successfully by establishing SystemSuitability, Specificity, Linearity, Accuracy, Limit of Detection, and Limit of Quantification. Specificitywasvalidated by assessing the separation of impurities and confirming the absence of interference fromthe placebo. Linearity was established by analysing a series of standard solutions at various concentration levels, withthecorrelation coefficient determined to be greater than 0.999. Accuracy was determined through recovery studiesconducted at three concentration levels, with the percentage recovery remaining within the acceptable range of 80- 120%. The limit of detection (LOD) and limit of quantification (LOQ) were determined using the signal-to-noiseratio method.
