Volume 97, Issue 6 - Special Issue: 9th International Conference for Young Chemists (ICYC 2024); Guest Editors: Ridhwan Adam and Mineesha Sivakumar

This study investigates the feasibility of use electroplating wastewater as a source of copper (Cu) dopants to improve the photocatalytic efficacy of TiO 2 under visible light for the disinfection of water contaminated with Escherichia coli . The Cu-doped TiO 2 was produced by the sol-gel process, employing titanium tetra-isopropoxide (TTIP) and Cu(II) ions derived from wastewater. By modifying the concentration of Cu(II), TiO 2 -Cu photocatalysts with differing copper concentrations were synthesized. The doping procedure substantially decreased the band gap of TiO 2 , facilitating activation under visible light and markedly enhancing its photocatalytic efficacy. The ideal Cu doping concentration was determined to be 0.60 %, which decreased the band gap from 3.20 eV (pure TiO 2 ) to 2.88 eV. Under visible light, the TiO 2 -Cu (0.60 %) photocatalyst attained a remarkable 98.21 % reduction of E. coli after 30 min, in contrast to a mere 38.42 % reduction by undoped TiO 2 . This study emphasizes the feasibility of using industrial wastewater to develop economical and effective TiO 2  photocatalysts for water purification purposes.

The 15-lipoxygenase (15-LOX) plays a key role in various diseases associated with inflammation. A geranylated acylphloroglucinol, namely 2,4,6-trihydroxy-3-geranylacetophenone or tHGA, 1 is a natural lead compound which exhibited significant LOXs inhibition. To further improve its 15-LOX inhibitory activity, xanthone moiety was incorporated into its scaffold using molecular hybridization (MH). In vitro soybean 15-LOX inhibition showed that all synthesized hybrids, 8a-c , 9a-c showed 4.5 to 590 times higher activity than tHGA, 1 with IC 50 values ranging from 0.04 to 5.27 µM. Structure activity relationships (SARs) identified that aromatic substitutions (–Cl, –N(C 2 H 5 ) 2 ) on ring C of xanthenone improved activity. The most potent hybrid, 9b exhibited the highest docking score (−10.67 kcal/mol), with molecular dynamics (MD) simulations (100 ns) validating its strong soybean 15-LOX inhibitory potential. The results suggest the therapeutic potential of these LOX inhibitors in inflammation and provide valuable insight and understanding for further structural optimization around the tHGA 1 scaffold.

Consumer demand for food safety and quality is driving innovation in eco-friendly and intelligent food packaging. This intelligent packaging can monitor product quality and reduce the risk of spoilage. One innovation uses natural indicators, such as curcumin, which is sensitive to changes in pH and can detect food spoilage. Research on intelligent packaging with curcumin indicators based on ganyong starch with nanocellulose from corn husk has never been done. Isolation of nanocellulose from corn husk produced a yield of 40.84 %. Morphological analysis showed irregular shape and size, with crystallinity of 57.77 % and an average particle size of 230.9 nm. Tests on vaname shrimp ( Litopenaeus vannamei ) showed that the ganyong-nanocellulose-curcumin film can monitor the freshness of shrimp through color changes from yellow to red under alkaline conditions, indicating spoilage. Ammonia during spoilage caused weight loss, soft texture, and increased TVBN value. Curcumin-based indicators affect intelligent packaging properties, reducing moisture content, water vapor transmission rate, solubility, and elongation while increasing tensile strength, density, and thickness. This intelligent packaging film has great potential for monitoring seafood freshness, making it a promising innovation.

The hypoxia-inducible factor (HIF) prolyl hydroxylase domain (PHD) inhibitors can potentially treat ischemic and hypoxic-related diseases, as demonstrated by their use in anemia treatment. An AlphaScreen assay was utilized to assess the PHD2 inhibition of the 2-( 1H -1,2,3-triazol-1-yl)acetic acid (TA) derivatives ( 1–14 ), which were synthesized using copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC) reaction. Most of the TA derivatives did not inhibit PHD2 effectively, with compound 14 demonstrating weak inhibition at 100 µM (>50 %). Docking experiments revealed that 14 forms hydrogen bond interactions with Arg 383 and binds to the PHD2 active site iron in a bidentate manner. Molecular dynamic simulation analysis shows 14 resembles but differs from the positive control inhibitor bicyclic isoquinoline (BIQ). It displays stable dynamic characteristics, with some flexible areas stabilizing upon binding to PHD2. The total binding energies for BIQ-PHD2 and 14-PHD2 were determined to be −42.90 kcal/mol and −36.08 kcal/mol, respectively. These values suggest that 14 and BIQ have similar binding affinities. In conclusion, structural changes of 14 may result in the development of an effective PHD2 inhibitor. However, most TA derivatives showed strong binding in docking studies but did not demonstrate good inhibitory activity against PHD2.

Zerumbone is a marker compound of Zingiber zerumbet that has antioxidant and anticancer properties. It exhibits low solubility in water, necessitating methods to enhance it has solubility, such as the creation of microparticles with chitosan in oleic acid. Therefore, this research aimed to isolate zerumbone from Z. zerumbet rhizome and determine the formation of its microparticles in chitosan in oleic acid. Zerumbone isolated by recrystallization the Z. zerumbet essential oil. Six different formulations of microparticles with chitosan (2.5–3.0 %), TPP as cross-linker, oleic acid as surfactant, and zerumbone. The formation of microparticles was analyzed using FTIR. The results showed a zerumbone yield of 0.11 % decibels. The particle size of the best microparticle was 5.516 μm, absorptive efficiency is 47 %, and amide linkages between the chitosan and oleic acid were confirmed based on FTIR. The microparticles have LC 50 value lower than native zerumbone. The zerumbone microparticles in chitosan-modified oleic acid have great potential for zerumbone delivery.

In this study, carbon and nitrogen co-doped TiO 2 nanocomposites (C–N–TiO 2 ) were successfully synthesized by the hydrothermal and low temperature calcination method with ultrasound (US) assistance for photocatalytic degradation of diclofenac (DCF). It was found that the introduction of US at two particular synthesis steps would obviously improve the photocatalytic properties of C–N–TiO 2 . Characterizations indicated the enhancement was owing to the integrative effects of the holonomic crystal structure and special morphology properties. Under LED visible light irradiation of 450 nm wavelength, C–N–TiO 2 could achieve excellent degradation rate of 97 % at 3 h with dosage of 0.4 g L −1 . The role of full-process sonication to affect the properties of C–N–TiO 2 was also revealed. The result of this study is expected to provide a feasible and easy way to improve the ability of semiconductor catalysts for water purification.

Surface coating of graphene oxide (GO) on membrane surfaces often suffers from low stability, with the GO layer prone to swelling and detachment during filtration. Cross-linking with environmentally friendly amino acids is expected to enhance the interfacial interaction between GO nanosheets and membrane surface via van der Waals interactions. This study introduces glycine (Gly) and diglycine (diGly) as cross-linking agents to improve the stability and performance of GO nanocomposite membranes. Field emission scanning electron microscopy (FESEM) images revealed that amino acid-crosslinked GO formed a thick pile structure on the membrane surface. The chemical bonding between GO and glycine derivatives was confirmed by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analyses. Stability test via continuously running water across the membrane surface in a crossflow filtration cell showed that cross-linking with glycine derivatives reduces the tendency of GO detachment from the self-fabricated polyethersulfone (PES) membrane surface. Ultrafiltration tests demonstrated that water permeability of nanocomposite membranes increased in the order of diGly-GO (14.70 LMH bar −1 ) > Gly-GO (8.66 LMH bar −1 ) > GO (4.57 LMH bar −1 ), without compromising bovine serum albumin (BSA) rejection efficiency (82–84 %). However, the reduction of hydroxyl groups in Gly-GO and diGly-GO nanocomposite membranes made them more susceptible to BSA fouling. Consequently, the pristine GO nanocomposite membrane exhibited the lowest flux declination rate and the highest flux recovery rate among the membranes. Overall, the results indicate that cross-linking GO nanosheets with glycine derivatives enhances membrane permeability and stability by improving the stacking of GO nanosheets.

Malaria continues to pose a significant threat to global health, demanding the development of novel antimalarial agents. This study investigated the antimalarial potential of eleven (11) furanyl-chalcone derivatives synthesized from two distinct furan sources: 2-acetylfuran and furfuraldehyde with Claisen–Schmidt condensation under base conditions, and successfully synthesized target compound with yields ranging from 67 % to 94 %. Structural characterization was achieved using spectroscopic techniques, including NMR, IR, and GC-MS. Our findings revealed that compounds derived from 2-acetylfuran exhibited superior antimalarial activity compared to their furfuraldehyde counterparts. Compounds B1 and B4 demonstrated the most promising activity with IC 50 values of 1.01 μM and 1.04 μM, respectively against P.falciparum FCR-3 strain. Our analysis revealed that B4 forms a stable hydrogen bond with Ser108 in the active site of wild-type P f DHFR, with a binding affinity of −6.7 kcal/mol. Importantly, this interaction was preserved even in the presence of a mutation at this residue, with B4 forming a hydrogen bond with Asn108 in the mutant enzyme, exhibiting a binding affinity of −7.0 kcal/mol. This suggests that B4 has the potential to overcome pyrimethamine resistance. Further analysis, utilizing DFT calculations and MEP, identified B4 as the most reactive compound within the series. The reactive site was located in the carbonyl group, with enhanced reactivity attributed to the presence of the electron-rich furan ring and the ortho -methoxy substituent.