Azobenzene (AB) and its derivatives exhibit reversible photoisomerization, making them promising candidates for molecular switches and optoelectronic applications. In this study, the electrochemical behavior of AB was investigated in surfactant-based organized media, including micelles, reverse micelles, and microemulsions formed using the cationic surfactant cetyltrimethylammonium bromide (CTAB). UV-visible spectroscopy confirmed the characteristic π-π* electronic transition of AB, while dynamic light scattering measurements revealed nanoscale organization with particle sizes below 10 nm in all media. Cyclic voltammetry showed that the redox behavior of AB is strongly governed by the interfacial environment of the surfactant assemblies. CTAB exhibits characteristic peaks arising from the adsorption/reduction of CTA⁺ at the electrode surface, which overlap with the electrochemical response of AB in micellar media. In contrast, reverse micellar and microemulsion systems exhibit well-defined cathodic (~ -0.70 V) and anodic (~ 0.25 V) peaks of AB with the interference of CTAB reduction. The results highlight the influence of surfactant-based nanostructures on the electrochemical properties of AB, with a foundation for designing photoresponsive molecular devices with enhanced electrochemical control. J. Bangladesh Acad. Sci. 50(2); 269–281: June 2026
Deterioration of groundwater (GW) quality due to natural and anthropogenic activities remains a critical concern in the Dhaka-Narayanganj city of Bangladesh because it is the primary drinking water (DW) source for millions of slum dwellers, and comprehensive health risk assessments integrating advanced pollution indices (PIs) and Carcinogenic Risk (CR) evaluation remain limited. Here, GW quality with heavy metal (HM) contamination and associated human health risks were assessed in 23 slum areas across the Dhaka-Narayanganj city by measuring physicochemical parameters along with concentration of nutrients and HMs. Furthermore, the Canadian Council of Ministers of the Environment Water Quality Index (CCME-WQI) and multiple PIs based on the obtained concentration of HMs were evaluated. Most of the physicochemical parameters and concentration of nutrients were within the World Health Organization (WHO) limit of DW, and the order of nutrient levels was nitrate ˃ phosphate ˃ ammonia. Among all HMs, Fe was the principal aesthetic concern (176 - 470 μg/L), with 4 stations exceeding the limit of WHO (300 μg/L) and As, Cr, Hg, Mn, and Pb being below health-concern limits. PIs classified 87 % of stations as low contamination, while CCME-WQI categorized 82.6 % as "good," 13 % as "excellent," and one as "fair." However, CR assessment identified that 5 stations (21.7 %) in Narayanganj and Shiddhirganj industrial areas pose “unacceptable” lifetime CR (>1×10⁻⁴) due to continuous ingestion and dermal contact with As-contaminated GW over many years. Standard water quality indices underestimate chronic health risks, so carcinogenic assessments must be added to regular GW monitoring to protect vulnerable slum communities. J. Bangladesh Acad. Sci.50(2); 283–298: June 2026
A number of 5-substituted isatin derivatives (2–6) were synthesized from Nbenzylisatin (1) by multistep organic reaction. Bromination of isatin followed by Suzuki-Miyaura coupling reaction with commercially available organoboron reagents afforded the compounds 2–6 with moderate yield. All the compounds were characterized using different spectroscopic techniques and their cytotoxicity was studied by brine shrimp lethality bioassay. Among these compounds, 2, 3, 5, and 6 showed moderate cytotoxicity with LC50 values 54.0, 76.5, 58.3, and 76.3 μg/mL, respectively, whereas compound 4 showed significant cytotoxicity with an LC50 value of 33.2 μg/mL. Structural modifications significantly affected electronic energy, dipole moment, and charge distribution. Compound 6 showed the highest dipole moment, suggesting greater polarity and potential intermolecular interaction capability. Frontier molecular orbital analysis identified compound 4 as the most reactive analogue, characterized by the lowest HOMO-LUMO energy gap, lowest hardness, and highest softness. J. Bangladesh Acad. Sci. 50(2); 247–257: June 2026
Postharvest decay caused by Colletotrichum gloeosporioides (anthracnose) and Lasiodiplodia theobromae (stem-end rot) accounts for significant economic losses in global mango (Mangifera indica L.) value chains. While synthetic fungicides remain the primary control measure, escalating concerns regarding chemical residues and environmental toxicity necessitate the development of bio-based alternatives. This study identified and characterized the potent antifungal efficacy of 3-methylpentanoic acid (3- MP), a volatile organic compound (VOC) derived from the endophyte Bacillus safensis. In vitro assays demonstrated that 3-MP exerts dosedependent inhibition on critical fungal life stages, including mycelial expansion, conidial germination, and appressorium formation. Complete inhibition was achieved at concentrations as low as 200 μM for C. gloeosporioides and 300 μM for L. theobromae. In vivo application significantly suppressed disease severity, while storage trials revealed that 3- MP treatments (specifically at 100 μM) simultaneously delayed fruit ripening and minimized physiological weight loss. As a "Generally Recognized as Safe" (GRAS) compound, 3-MP represents a dual-action breakthrough: it serves as both a high-efficacy bio-fumigant and a physiological preservative. These findings provide a sustainable framework for replacing synthetic agrochemicals with microbial-derived volatiles, offering a scalable solution for the long-term preservation of tropical fruits. J. Bangladesh Acad. Sci. 50(2); 169–180: June 2026
The complexation between the oxovanadium(IV) ion and the levofloxacin (levH) was examined in pure solvents (water; H2O, dimethylformamide; DMF, and methanol; MeOH) and mixed solvents (dimethylformamidewater; DMF-H2O and methanol-water; MeOH-H2O) using the spectrophotometric method. The complexation reaction was also observed in aqueous solution (pH 2) at various ionic strengths and temperatures. The results indicate that the complex has a 1:2 stoichiometry in all pure and binary mixed solvents. The Harvey and Manning equation was used to calculate the stability constant (logβ) of the oxovanadium(IV)-levofloxacin [VIVO(lev)2] complex. In pure solvents, the logβ values of the [VIVO(lev)2] complex follow the order MeOH > H2O > DMF. The MeOH-H2O system has substantially larger logβ values than the DMF-H2O system. Changes in logβ versus the dielectric constant (1/D) of binary mixed solvents show a linear relationship. As ionic strength and temperature increase in aqueous solution, the stability constant of the [VIVO(lev)2] complex decreases. Based on the thermodynamic parameters (ΔG, ΔH, and ΔS), the complexation reaction between the oxovanadium(IV) cation and levofloxacin is spontaneous and exothermic. J. Bangladesh Acad. Sci 50(2); 207–214: June 2026
Protein, an essential and indispensable component of our diet, provides amino acids for the development, growth, and maintenance of human body. There is growing concern that protein intake from certain sources and dietary patterns may be a triggering factor for colorectal cancer (CRC). However, the link between dietary protein intake and CRC remains unclear, and the researchers are working to unravel the connection and its implications. Although specific reports showed red and processed meat linked with an increased risk of CRC, several recent studies exhibited CRC inversely tied with certain types of amino acid intake. Accumulating data indicate that CRC development is multifactorial, including dietary and lifestyle factors, environmental factors, and genetic factors. Moreover, the development and progression of CRC depend on several disruptive molecular pathways. These findings collectively suggest that protein source, dietary diversity, and food preparation methods are more meaningful determinants of CRC risk than protein intake per sec. A balanced diet incorporating varied protein sources, along with fiber, vitamins, and minerals, remains the most evidencesupported strategy for CRC prevention. This article argues with the recent conceivable theories about CRC development, progression and its relationship with dietary protein and synthesizes current evidence on the relationship between dietary protein intake and CRC riskconcluding that no direct causal link exists between overall protein consumption and CRC development. J. Bangladesh Acad. Sci. 50(2); 157–167: June 2026
Bangladesh is the worst affected country in the world by arsenic contamination of groundwater. The widespread installation of low-cost shallow tubewells, initially intended to control waterborne diseases, has exposed millions to high arsenic concentrations through drinking water. Arsenic (As) in groundwater in the absence of dissolved oxygen is predominantly present as As(III) which is more toxic than As(V). Food, particularly rice, represents another significant pathway of arsenic exposure. Approximately75% of dry-season irrigation relies on groundwater, arsenic accumulation in cropsespecially ricemay substantially contribute to the total body burden in affected areas. The cause, magnitude, and health impacts of arsenic contamination of groundwater have been investigated in many studies. This paper provides an updated synthesis based on available research. The paper also presents a comprehensive analysis of the cause and extent of contamination, andits impacts on drinking water, agro-environment and prevalence of arsenic-related diseases. Arsenic risk management measures implemented in Bangladesh are discussed. The analysis includes estimates of population exposed to varying arsenic concentrations, an assessment of the effects of contaminated irrigation water on soil, paddy plants, and rice grains, and an exploration of the correlation between average drinking water arsenic contents at the Upazila (sub-district) level and the prevalence of arsenicinduced skin lesions in that Upazila. J. Bangladesh Acad. Sci. 49(2); 157-177: December 2025
We present a brief overview on Intuitionistic sets and its relations which cuts across some definitions, operations, relations and functions on intuitionistic set. In this article, we have shown various operations and their applications using intuitionistic set. We have also seen that relationships can be established using intuitionistic sets, which work similarly to usual relations. Reflexive, Symmetric, Antisymmetric and Transitive relations can be described using intuitionistic set theory, which demonstrated better results than the previous classical set. J. Bangladesh Acad. Sci. 49(2); 287-293: December 2025
One of the major challenges for a densely populated country like Bangladesh is energy shortage. For electricity generation, the country mostly relies on fossil fuels such as furnace oil, natural gas, and coal. With the environmental problems associated with fossil fuels, the global transition to renewable energy sources is inevitable. Ocean waves represent a promising renewable energy source in this regard. A large area of Bangladesh is covered by the sea, which offer significant potential for wave energy. Wave energy can be converted into electricity using a range of devices, including point absorbers, attenuators, wave surge devices, and oscillating water columns. However, these devices are fixed at specific locations, depend on particular wave profiles, and require expensive underwater cables. Against this background, the Mobile Wave Crawler (MWC), an autonomous wave energy converter, appears to be a promising solution. This work assesses the feasibility of the device, and evaluates its potential energy output. It also demonstrated a levelized cost of energy (LCOE) of USD 0.12 kWh for an energy-producing machine with an hourly rated capacity of 1 MW. Although this cost is higher than of traditional fossil-fuel-based power plants, the technology can be promoted as sustainable and environmentally friendly. This research illustrates that the proposed solution is a feasible source of green energy for the offshore islands of Bangladesh, identifies the major challenges, and suggests possible solutions. In addition, the study estimates the required number of Mobile Wave Crawlers for several example islands. For instance, four MWC units are required for each of Bhashan Char and Shah Porir Dwip, while only one unit is required for each St. Martin's Island and Dublar Char to meet their respective energy demands. J. Bangladesh Acad. Sci. 49(2); 215-225: December 2025
Antidepressant drugs are frequently used in the treatment of depression. Their effects on locomotory behavior have been poorly studied in human and Drosophila models. In this study, the effects of an antidepressant drug on larval crawling, negative geotaxis, and TOR gene expression were investigated in a Drosophila model. Drug-treated flies showed significantly higher activity in the negative geotaxis assay. However, no statistically significant differences were observed in the other behavioral assays or in TOR gene expression. J. Bangladesh Acad. Sci. 49(2); 295-298: December 2025
In this paper, the AC impedance properties of Bi1-xYxFe0.7Mn0.3O3 (BYFMO) ceramics with x values from 0.00 to 0.20 were studied. It was manufactured via solid-state chemistry, and during manufacturing, sintering at temperatures was at 800, 825, and 850°C, and optimal bulk density was at 825°C. X-ray diffraction investigation verified differences in lattice parameters resulting from doping-induced strain and defect structures, suggesting the presence of a rhombohedral phase along with small secondary phases. Field Emission Scanning Electron Microscopy (FESEM) demonstrated a porous microstructure with grain sizes ranging from 1.22 to 1.89 μm. Energy Dispersive X-ray spectroscopy confirmed the elemental composition. The dielectric constant (ε′) demonstrated a frequencydependent reduction, stabilizing beyond 10 kHz. At 100Hz, ε′ rose from 65 to 78 at 100 Hz with increasing Y doping due to a reduction in the quantities of oxygen vacancies. Impedance spectroscopy revealed distinct semicircular patterns in undoped material, indicating grain and grain boundary effects, while doped samples mostly demonstrated grain conduction, elucidating multiferroic electrical transport mechanisms. We have gotten the maximum grain resistance 199.02 MΩ for highest doping at x = 0.20. J. Bangladesh Acad. Sci. 49(2); 271-285: December 2025
The feasibility study for the photovoltaic solar systems in Rajshahi, Bogura, and Sirajganj regarding Bangladesh, comprehensively addresses financial, technical, and environmental factors to attract both the national and international investors. The objective of the analysis is to evaluate photovoltaic (PV) solar systems in northern cities of the Bangladesh; Rajshahi, Bogura, and Sirajganj to minimize the effect of the global warming caused by burning of the fossil fuels as well as to improve region’s sustainable development, which was hampered by the factory pollution. To analyze study and the verify its techno-economic and environmental sustainability, RETScreen Expert and Homer software is utilized. Sensitivity analysis emphasizes importance of the considering the diesel prices, inverter efficiency, and interest rates, as these factors significantly impact cost of energy (COE). Among these zones, Rajshahi attitudes out with lowest total emissions and the carbon dioxide levels, making it the furthermost favorable option for the reducing pollution and advancing the sustainable technology in this region. J. Bangladesh Acad. Sci. 49(2); 189-204: December 2025
Cloves (Syzygium aromaticum) are aromatic flower buds that have been extensively studied for their culinary, medicinal, and economic value. Bangladesh has Indonesian (CIS), Indian (CID) and Sri Lankan (CSI) cloves. This study investigates the bioactive compounds, proximate analysis, physicochemical properties, and antibacterial efficacy of clove essential oils from three commercially available brands in Chattogram. Using Gas Chromatography-Mass Spectrometry (GC-MS), the primary bioactive compounds identified were eugenol, eugenol acetate, and β- caryophyllene, with significant variations in their concentrations across brands. Proximate analysis revealed differences in moisture, ash, and volatile content, highlighting disparities in quality and purity. Physicochemical properties were assessed. Antibacterial efficacy was evaluated using the agar disc diffusion method against Escherichia coli and Staphylococcus aureus and Pseudomonas aeruginosa, as indicated by its minimal inhibitory concentration (MIC) values. These findings underscore the importance of brand selection in ensuring the therapeutic and functional efficacy of clove essential oil, emphasizing the need for stringent quality control in the market. J. Bangladesh Acad. Sci. 49(2); 243-253: December 2025
We documented amphibian predation by the greater false vampire bat (Lyroderma lyra) in Bangladesh, expanding current knowledge of its trophic ecology. This observation highlights the ecological role of this species as both an insectivore and a carnivore, and underscores the need to investigate the frequency and ecological drivers of such predatory behavior. J. Bangladesh Acad. Sci. 49(2); 299-301: December 2025
Energy drink consumption has escalated, especially among the younger generation, credited to their stimulating properties, mainly because of their caffeine and carbohydrate contents. Given the potential health risks associated with excessive consumption of these substances, it is imperative to examine the composition of energy drink products on the market. This study used an analytical quantitative method to determine the mass concentrations of total solids, caffeine, and carbohydrates in eight brands of energy drink on sale in Dhaka, Bangladesh, using a composite, cost-effective experimental design. Total solid mass contents were 10.30 to 13.13 g per 100 mL of drinks, caffeine was found 233.30 to 546.48 mgL-1, and carbohydrates were found 7.09 to 11.15 g per 100 mL energy drink using the double beam UV-visible spectrophotometer. The accuracy of the results was also indicated by the low standard deviation values of 1.04 to 4.39 for caffeine and 0.08 to 0.23 for carbohydrate, and the relative standard deviation of 0.26 to 1.75% for caffeine and 0.54 to 2.72% for carbohydrate. There was a need for proper health, legal, and standard considerations in energy drink manufacturing, given the results. J. Bangladesh Acad. Sci. 49(2); 205-214: December 2025
In the current study, ten F1 hybrids and their five parents were evaluated for agronomic, post-harvest, and nutritional traits. Significant genetic variation was observed among the traits, which grouped the planting materials into four phylogenetic clades. High heritability, coupled with high genetic advance was recorded for fruits per plant (99.61% and 170.55%), single fruit weight (99.06% and 102.09%), and vitamin C content (99.98% and 177.53%), suggesting that these traits are governed predominantly by additive gene action. Pearson’s correlation and path coefficient analyses identified fruit diameter, number of secondary branches, single-fruit weight, and skin thickness as key traits positively associated with fruit yield, while increased skin thickness also contributed to enhanced shelf-life. Based on mean performance, the hybrids BT-15 × BT-3, BT-8 × BT-15, and BT-8 × BT-14 emerged as promising candidates for high yield. In addition, BT-8 × BT-11 and BT-8 × BT-15 exhibited superior shelf life and nutritional quality. Overall, the findings highlight the potential of integrating yield, post-harvest, and nutritional traits into selection indices for the development of superior tomato hybrids. J. Bangladesh Acad. Sci. 49(2); 255-269: December 2025
Acinetobacter nosocomialis, a nosocomial pathogen, particularly affecting immunocompromised individuals. This species is retaining multidrug resistance and it is increasing over the time. The organism is dependent on human hosts for survival and exerts several methods to circumvent both innate and adaptive immune response. Some of the defence systems are intrigued by extracellular or intracellular proteins of this pathogen. Hence, characterize the unannotated proteins, also called hypothetical proteins, could play a big role in identifying novel treatment targets. In this study, we focused on the characterization of a hypothetical protein (HP) (accession No. KDM58575.1) derived from Acinetobacter nosocomialis. In-silico tools was employed to examine the hypothetical proteins, focusing on physicochemical parameters, subcellular localisation, secondary structure, three-dimensional structure, and functional annotation. To study the active site, protein-protein interactions and molecular docking, the bioinformatics tools CASTp, the STRING server, and PyRx were utilized, respectively. The findings identified this protein as a multicopper oxidase involved in detoxification, transport, and metal binding. The 3D structure derived from the SWISS Model server, and it was matched 89.92% similarity to the AlphaFold DB model A0A0M3ADD5.1, a copper oxidase derived from Acinetobacter sp. AG1 (gene: A0A0M3ADD5_9GAMM). This protein also showed considerable biological activity and consists of five functional domains, like cupredoxin. The proteinprotein interaction also delineates the essential partners required for bacterial viability, whereas KEGG suggested the protein associated with the bacterial two-component signalling system. In docking analysis, the ligand exhibited significant binding activities and suggesting a potential target for treating nosocomials infection. This study highlights the bioinformatics tools for protein characterization and understanding molecular pathways for Acinetobacter nosocomialis. Furthermore, it offers significant insights into the development of innovative therapeutic procedures. J. Bangladesh Acad. Sci. 49(2); 227-242: December 2025
With rising antibiotic resistance, the discovery of novel antimicrobial compounds has become increasingly crucial. In silico genome mining is widely used to predict secondary metabolite production prior to laboratory testing. In this study, 505 Staphylococcus aureus genomes from the NCBI database were analyzed using antiSMASH 7.0, which identified a class I lanthipeptide gene cluster in 206 strains. Although antiSMASH annotated this gene cluster as hyicin 3682 and the RefSeq genome database classified it as a ‘gallidermin- or nisin-family lantibiotic’, the prepeptide sequence encoded by the cluster is identical to that of the S. aureus bacteriocin (Bsa) lantibiotic. Moreover, other genes within the cluster share the same number and orientation as the Bsa loci found in community-acquired S. aureus strains. Variations in prepeptide sequences and gene numbers revealed four distinct Bsa variants. Overall, this analysis supports the presence of lantibiotic gene clusters in pathogenic strains and highlights the potential of genome mining to reduce time, cost, and labor in antimicrobial discovery. J. Bangladesh Acad. Sci. 49(2); 179-188: December 2025
Cryptochrome 2 (CRY2) is one of the four proteins of the cell-autonomous molecular clock in mammals. Non-synonymous SNPs of the cry2 gene, resulting in missense variants of CRY2, were correlated with metabolic disorders, cancers, and autism spectrum disorders. This in silico analysis aimed to investigate these missense SNPs having deleterious structural and functional impacts on the human CRY2 protein. Multiple computational tools, homology modeling, and molecular dynamic simulation reported an impact on protein structural stability, function, and binding with PER2 and FBXL3. Our results suggest that missense variants of hCRY2 with L74P, L274P, L309P, F315V, and Y485H mutations were the most destabilizing. These were found to have an overall altered structure, especially in the FAD binding pocket, which in turn can impact the binding of CRY activating compounds, regulatory proteins FBXL3 and PER2. These five missense variants warrant detailed in vitro and in vivo investigations to solidify our findings. J. Bangladesh Acad. Sci. 49(1); 57-72: June 2025
