UV Vis Spectra Research Articles

Identification of novel flower anthocyanins of Delphinium grandiflorum cultivars

Flower color is one of the most important properties of ornamental flowers. Information on the kinds of pigments that flowers can biosynthesize is useful for breeding cultivars focused on flower colors. The flower colors of regular ornamental delphinium cultivars are blue, violet, purple, pink, and white. The pigments of these flowers are delphinidin-based anthocyanins. It has been reported that the typical modification in delphinium anthocyanins involves the transfer of glucose and p-hydroxybenzoic acid molecules to the 7-position of delphinidin one by one, and it was predicted that other unidentified anthocyanins are present in addition to the already reported ones. Recently, light pink flowers that accumulate pelargonidin-based anthocyanins were reported from cultivars derived from Delphinium grandiflorum. Converting delphinidin-based anthocyanins to pelargonidin-based ones is considered key to producing red flowers in delphinium. Hence, we investigated anthocyanins of blue, mauve, light pink, and white flowers of D. grandiflorum cultivars. We isolated anthocyanins and analyzed them using HPLC, TLC, UV–vis spectra, FABMS, and NMR. Using these methods, we identified two novel delphinidin-based anthocyanins and three novel pelargonidin-based anthocyanins: delphinidin 3-O-[6-O-(α-rhamnopyranosyl)-β-glucopyranoside]-7-O-[6-O-(p-hydroxybenzoyl)-β-glucopyranoside] (2), pelargonidin 3-O-[6-O-(α-rhamnopyranosyl)-β-glucopyranoside]-7-O-[6-O-(4-O-(6-O-(p-hydroxybenzoyl)-β-glucopyranosyl)-p-hydroxybenzoyl)-β-glucopyranoside] (5, rubrodelphin), pelargonidin 3-O-[6-O-(α-rhamnopyranosyl)-β-glucopyranoside]-7-O-[3-O-(β-glucopyranosyl)-6-O-(4-O-(6-O-(p-hydroxybenzoyl)-β-glucopyranosyl)-p-hydroxybenzoyl)-β-glucopyranoside] (6), delphinidin 3-O-[6-O-(α-rhamnopyranosyl)-β-glucopyranoside]-7-O-[3-O-(3-O-(6-O-(p-hydroxybenzoyl)-β-glucopyranosyl)-β-glucopyranosyl)-6-O-(4-O-(6-O-(p-hydroxybenzoyl)-β-glucopyranosyl)-p-hydroxybenzoyl)-β-glucopyranoside] (7), and pelargonidin 3-O-[6-O-(α-rhamnopyranosyl)-β-glucopyranoside]-7-O-[3-O-(3-O-(6-O-(4-O-(6-O-(p-hydroxybenzoyl)-β-glucopyranosyl)-p-hydroxybenzoyl)-β-glucopyranosyl)-β-glucopyranosyl)-6-O-(4-O-(6-O-(p-hydroxybenzoyl)-β-glucopyranosyl)-p-hydroxybenzoyl)-β-glucopyranoside] (9, rosedelphin), along with four known anthocyanins. The flowers of five blue cultivars accumulated cyanodelphin (8) as the dominant pigment. The shapes of visible absorption spectra of these five blue flowers were similar, indicating that the color and the absorption spectra were the typical ones for delphinium blue color produced by 8. The mauve flower color was due to a mixture of delphinidin-based anthocyanins in various polyacylated levels at the 7-position. The light pink flowers accumulated pelargonidin-based anthocyanins 5, 6, and 9. These pigment structures showed that the pelargonidin-based anthocyanins modified in the same way as in the originally biosynthesized delphinidin-based anthocyanins even though aglycone was replaced by pelargonidin in these anthocyanins.

Transition metal ion doped Mg-Zn manganites for optoelectronic device applications

This work aimed at synthesizing Mg0.5Zn0.5Mn1.95(Fe/Co/Ni)0.05O4 nanoparticles using sol–gel auto-combustion method. Structural studies (XRD, Rietveld, Raman) confirmed the tetragonal spinel structure with I41/amd space group and average crystallite size ranged between 18–22.8 nm. The morphologies and compositions of these nanoparticles were studied using SEM and EDX. UV–Vis spectra demonstrated significant enhancement in the absorbance values. The estimated optical band gaps vary between 1.6 to 1.77 eV. Frequency-dependent dielectric and impedance spectroscopic studies (at room temperature) reveal exciting results. Thus, tailoring of dielectric properties and optical band gaps of these transition metals doped Mg-Zn manganite nanoparticles may find potential applications in optoelectronics devices.

A comparative study of the biosynthesis of CuNPs by Niallia circulans G9 and Paenibacillus sp. S4c strains: characterization and application as antimicrobial agents

BackgroundBiosynthesis of metallic nanoparticles using microorganisms are a fabulous and emerging eco-friendly science with well-defined sizes, shapes and controlled monodispersity. Copper nanoparticles, among other metal particles, have sparked increased attention due to their applications in electronics, optics, catalysis, and antimicrobial agents.ResultsThis investigation explains the biosynthesis and characterization of copper nanoparticles from soil strains, Niallia circulans G9 and Paenibacillus sp. S4c by an eco-friendly method. The maximum reduction of copper ions and maximum synthesis CuNPs was provided by these strains. Biogenic formation of CuNPs have been characterized by UV–visible absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray analysis and transmission electron microscopy analysis. Using UV-visible spectrum scanning, the synthesised CuNPs’ SPR spectra showed maximum absorption peaks at λ304&308 nm. TEM investigation of the produced CuNPs revealed the development of spherical/hexagonal nanoparticles with a size range of 13–100 nm by the G9 strain and spherical nanoparticles with a size range of 5–40 nm by the S4c strain. Functional groups and chemical composition of CuONPs were also confirmed. The antimicrobial activity of the biosynthesized CuNPs were investigated against some human pathogens. CuNPs produced from the G9 strain had the highest activity against Candida albicans ATCC 10,231 and the lowest against Pseudomonas aeruginosa ATCC 9027. CuNPs from the S4c strain demonstrated the highest activity against Escherichia coli ATCC 10,231 and the lowest activity against Klebsiella pneumonia ATCC 13,883.ConclusionThe present work focused on increasing the CuNPs production by two isolates, Niallia circulans G9 and Paenibacillus sp. S4c, which were then characterized alongside. The used analytics and chemical composition techniques validated the existence of CuONPs in the G9 and S4c biosynthesized nano cupper. CuNPs of S4c are smaller and have a more varied shape than those of G9 strain, according to TEM images. In terms of antibacterial activity, the biosynthesized CuNPs from G9 and S4c were found to be more effective against Candida albicans ATCC 10,231 and E. coli ATCC 10,231, respectively.

Tuning the bandgap of Cu(II) phosphinate coordination polymers by ligand selection and coordination geometry

Five coordination polymers, denoted as ICR-15, ICR-16, ICR-17, ICR-18, and ICR-19, were prepared using three previously reported phosphinic acids, namely H2PBP(Me), H2PBP(Ph), H2BBP(Ph), and one new ligand H3TPBTP(Me), in conjunction with Cu2+ cations. These coordination polymers were characterized with single crystal X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, thermal analysis, and UV–vis spectroscopy. The crystal structures of the coordination polymers were analysed, revealing a variety of coordination environments and distinct structural motifs. Optical band gaps determined from the UV–vis spectra of the coordination polymers range from 2.8 eV to 3.5 eV, corresponding to wide bandgap semiconductors. Interestingly, the coordination geometry of Cu2+ was found to have a negligible influence on the size of the direct or indirect band gap.

Green Synthesis of Silver Nanoparticles with Snake Fruit Peel Extract: A Preliminary Study For Optimization of The Preparation Technique

In Indonesia, the pulp of snake fruit is consumed while the peel remains unused. In this context, the phytochemical content of snake fruit aqueous extract was used as a reducing and capping agent in the preparation of silver nanoparticles (AgNPs). According to the phytochemical screening, snake fruit peel containing alkaloids, flavonoids, tannins, saponins, and polyphenols was used to synthesize AgNPs. Therefore, this research aimed to optimize the synthesis of AgNPs using snake fruit peel extract (Salacca zalacca) in terms of synthesis time, temperature and phytochemical screening. AgNPs were successfully synthesized using a volume ratio of 2:15 (20 mL of 1.00 mM AgNO3 to 150 mL of snake fruit peel extract) in a sealed container in a dark room. Furthermore, characterization was carried out using a UV-Vis spectrum and Fourier Transform Infrared Spectroscopy (FTIR). The UV-Vis spectrum characterization in a solution incubated for 30 minutes at 30 °C with a concentration of 1.00 mM AgNO3 was differentiated at a wavelength of 410 nm with an absorbance of 2.361. According to the FTIR characterization, there was an increase in the intensity of the O – H functional groups in the AgNPs solution compared to snake fruit peel extract. The results showed that the synthesis of AgNPs from snake fruit peel extract was optimal at a concentration of 1.00 mM AgNO3 at 30 °C and 30 minutes of incubation.

Pyrogallol intermediates elicit beta-amyloid secretion via radical formation and alterations in intracellular trafficking, distinct from pyrogallol-generated superoxide

This study unveils a novel role of pyrogallol (PG), a recognized superoxide generator, in inducing beta-amyloid (Aβ) secretion in an Alzheimer's disease (AD) cellular model. Contrary to expectations, the analysis of dihydroethidium fluorescence and UV-VIS spectrum scanning reveals that Aβ secretion arises from PG reaction intermediates rather than superoxide or other by-products. Investigation into Aβ secretion mechanisms identifies dynasore-dependent endocytosis and BFA-dependent exocytosis as independent pathways, regulated by tiron, tempol, and superoxide dismutase. Cell-type specificity is observed, with 293sw cells showing both pathways, while H4sw cells and primary astrocytes from an AD animal model exclusively exhibit the Aβ exocytosis pathway. This exploration contributes to understanding PG's chemical reactions and provides insights into the interplay between environmental factors, free radicals, and AD, linking occupational PG exposure to AD risk as reported in the literature.

Smart Contact Lens for Colorimetric Visualization of Glucose Levels in the Body Fluid.

Frequent blood glucose monitoring is a crucial routine for diabetic patients. Traditional invasive methods can cause discomfort and pain and even pose a risk of infection. As a result, researchers have been exploring noninvasive techniques. However, a limited number of products have been developed for the market due to their high cost. In this study, we developed a low-cost, highly accessible, and noninvasive contact lens-based glucose monitoring system. We functionalized the surface of the contact lens with boronic acid, which has a strong but reversible binding affinity to glucose. To achieve facile conjugation of boronic acid, we utilized a functional coating layer called poly(tannic acid). The functionalized contact lens binds to glucose in body fluids (e.g., tear) and releases it when soaked in an enzymatic cocktail, allowing for the glucose level to be quantified through a colorimetric assay. Importantly, the transparency and oxygen permeability of the contact lens, which are crucial for practical use, were maintained after functionalization, and the lenses showed high biocompatibility. Based on the analysis of colorimetric data generated by the smartphone application and ultraviolet-visible (UV-vis) spectra, we believe that this contact lens has a high potential to be used as a smart diagnostic tool for monitoring and managing blood glucose levels.

Exploring class III cellobiose dehydrogenase: sequence analysis and optimized recombinant expression

BackgroundCellobiose dehydrogenase (CDH) is an extracellular fungal oxidoreductase with multiple functions in plant biomass degradation. Its primary function as an auxiliary enzyme of lytic polysaccharide monooxygenase (LPMO) facilitates the efficient depolymerization of cellulose, hemicelluloses and other carbohydrate-based polymers. The synergistic action of CDH and LPMO that supports biomass-degrading hydrolases holds significant promise to harness renewable resources for the production of biofuels, chemicals, and modified materials in an environmentally sustainable manner. While previous phylogenetic analyses have identified four distinct classes of CDHs, only class I and II have been biochemically characterized so far.ResultsFollowing a comprehensive database search aimed at identifying CDH sequences belonging to the so far uncharacterized class III for subsequent expression and biochemical characterization, we have curated an extensive compilation of putative CDH amino acid sequences. A sequence similarity network analysis was used to cluster them into the four distinct CDH classes. A total of 1237 sequences encoding putative class III CDHs were extracted from the network and used for phylogenetic analyses. The obtained phylogenetic tree was used to guide the selection of 11 cdhIII genes for recombinant expression in Komagataella phaffii. A small-scale expression screening procedure identified a promising cdhIII gene originating from the plant pathogen Fusarium solani (FsCDH), which was selected for expression optimization by signal peptide shuffling and subsequent production in a 5-L bioreactor. The purified FsCDH exhibits a UV-Vis spectrum and enzymatic activity similar to other characterized CDH classes.ConclusionThe successful production and functional characterization of FsCDH proved that class III CDHs are catalytical active enzymes resembling the key properties of class I and class II CDHs. A detailed biochemical characterization based on the established expression and purification strategy can provide new insights into the evolutionary process shaping CDHs and leading to their differentiation into the four distinct classes. The findings have the potential to broaden our understanding of the biocatalytic application of CDH and LPMO for the oxidative depolymerization of polysaccharides.

A dual-purpose photocatalytic reaction for hydrogen evolution and simultaneous organic pollutant degradation of V2O5/Ppy based composite photocatalyst

The present work reports for the facile synthesis of novel vanadium oxide/polypyrrole (V2O5/Ppy) nanohybrids using various loadings of the V2O5. This novel hybrid photocatalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman, UV–Visible absorption spectra (UV–Vis), photoluminescence spectra (PLS) and N2 adsorption-desorption analysis. XRD and TEM results suggest that V2O5 with individual spherical shaped nanoparticles of around 20–25 nm, which is uniformly wrapped on the surface of the Ppy sheets. A significant reduction in the bad gap energy (3.06–2.13 eV) and prevent the electron-hole recombination process was examined by UV and PL studies. The photocatalytic degradation efficiency was carried out for Reactive Black 31 (RB 31) and 4-chlorophenol (4-CP) dyes under visible light. The results illustrate that the optimal hybrid catalyst could reach 99 % of removal efficiency towards RB31 with visible light irradiation for 60 min. Moreover, the catalyst show high TOC efficiency (88%) high apparent constant (0.9189 min−1), and good stability with multiple cycle experiments. The improved photocatalytic mechanism was also discussed in detail. In comparison to V2O5 (425 μmol−1h−1 of H2) and PPy (151 μmol−1h−1 of H2), the optimised composite, 15 wt% V2O5 incorporated PPy showed a remarkable production rate under visible light (2255 μmol−1h−1 of H2).

Preparation of novel Au-Nb3O7F nanosheets for the photodegradation of tetracycline hydrochloride.

Water pollution caused by antibiotics is a growing problem and photodegradation by efficient catalysts is an environmentally friendly technology that can effectively degrade organic pollutants in water. Here, a novel method was innovatively used to synthesize niobium oxyfluoride (Nb3O7F) nanosheets decorated with Au nanoparticles, which is the first report for the composites of Au and Nb3O7F. We prepared the Nb3O7F nanosheets via hydrothermal synthesis followed by deposition of Au nanoparticles on their surface using HAuCl4. The prepared samples were characterized by XRD, HRTEM, XPS, and UV-Vis. The diameters of most Au NPs are ranging from 5 to 25nm with an average size of about 16.9nm, as well as the Nb3O7F nanosheets in size ranging from 200nm to 700nm. The chemical composition of the Au-Nb3O7F showed a Au/Nb atomic ratio of 1/10, as well as a Nb/O/F ratio of 3/7/1. UV-Vis spectrum reveals a largest absorption peak at 520nm for the Au-Nb3O7F nanosheets. The prepared Au-Nb3O7F nanomaterials were applied to the visible-light photodegradation of tetracycline hydrochloride, with the photocatalytic degradation rate reached more than 50% under the optimal conditions within 1h. Capture experiments indicated that h+ and •O2 - are the main active substances involved during the course of the photodegradation. Furthermore, the proposed mechanism for the photodegradation of the novel Au-Nb3O7F nanosheets was given.

Theoretical screening of N-[5'-methyl-3'-isoxasolyl]-N-[(E)-1-(-2-thiophene)] methylidene]amine and its isoxazole based derivatives as donor materials for bulk heterojunction organic solar cells: DFT and TD-DFT investigation.

In the present work, the influence of aromatic ring substitution on a series of small-donor organic molecules (A, B, C, D, and E) with isoxazole cores was investigated for photovoltaic applications in organic solar cells. Frontier molecular orbital analysis, chemical reactivity descriptors, dipole moment, and population analysis showed that all the organic materials have intramolecular charge transfer abilities capable of donating electrons to the acceptor material (PCBM). The required photovoltaic parameters such as Voc, FF, Jsc, LHE, and other associated optoelectronic parameters are reported. The results demonstrate that aromatic ring substitution influences charge transfer and power conversion efficiencies of solar cells. That is, an increase in the aromatic character of a material increases its charge transfer, and as a result, its photovoltaic properties are increased. Additionally, all the investigated derivatives are good charge transporters with suitable electron reorganization energies, which are beneficial for minimizing energy loss. Hence, these organic derivatives with isoxazole backbones are promising materials and may provide fresh insights into the design of new materials for organic solar cell applications. All calculations were performed using DFT and the ORCA 4.1.0 program package as the main tool for geometry optimization and frequency calculations. The Avogadro 1.2.1 visualization tool was used to prepare all input files executed by ORCA 4.1.0. The BP86, B3LYP, and wB97M series of functionals coupled with the def2/TZVP basis set were employed for geometry optimization. All energy-related calculations were carried out using the M06-2x functional. Multiwfn version 3.7 was used for aromaticity and population analysis. Excited state and UV-visible spectra were simulated using the TD-DFT method at the CAM-B3LYP-D3, wB97X-D3, and PBE0-D3 coupled with the ma-def2-TZVP basis set. Moreover, solvent effects were incorporated using the SMD scheme as incorporated in the ORCA software. Lastly, the RIJCOSX approximations were used to speed up calculations while maintaining accuracy.

Investigating the Potential Pharmacological Applications of 5-Hydroxy-2 (hydroxymethyl)-4H pyran-4 one through Electronic Characterization and MM-GBSA Studies for Oxidative Stress and Tyrosinase Inhibition: A Quantum Chemical Approach

The study thoroughly examines the possible applications of 5 Hydroxy – 2 (hydroxymethyl) – 4 H pyran – 4 one. Through Quantum chemical analysis, the research rigorously evaluates the compound's properties, including its optoelectronics, geometrical structure, and intermolecular interactions. The geometrical structure parameters were optimized using a 6–311++G(d,p) basis set in the DFT/B3LYP method, and the resulting geometrical factors were then scaled to calculate probable vibrational wavenumbers. The Mulliken charges and MEP map were used to locate electrophilic, nucleophilic regions, and chemical reactivity was described using FMOs and Fukui function assessments. The multiwfn was employed to investigate topological analysis (surface distance projection and Hirshfeld maps). The UV-visible spectrum was used to estimate the absorption of maximum wavelengths, which was then correlated with the TD-DFT, DOS, and band structure investigations. The study also calculated parameters, including Total Energies, ZPE, Entropy, Dipole moment, and Heat Capacity for monomeric and dimeric units. Pharmacokinetics were used to determine the biological characteristics of the compound. The MM-GBSA simulation was performed, and the results suggest that this compound has the potential to be an enhancing anti-oxidant protection agent due to its high binding affinity and intermolecular interactions. These findings are crucial in developing therapeutic agents with pharmacological effects and potential toxicities.

Zygnema sp. as creator of copper oxide nanoparticles and their application in controlling of microbial growth and photo-catalytic degradation of dyes

Recently, focus has been placed on renewable sources, as they can be provided in large quantities at the lowest possible cost, in order to create nanoparticles. One of these sources is Zygnema moss which used in the present investigation to create Copper oxide nanoparticles (CuONPs). Several phenols and flavonoids were identified the extract of Zygnema sp. via analysis of High performance liquid chromatography. These constituents served as reducing and stabilizing agents for CuONPs. Characterization of CuONPs was performed via UV-visible spectrum that demonstrated peak at 252 nm, Transmission electron microscopy that showed spherical CuONPs with mean diameter of 30.06 nm, Fourier transform infrared spectroscopy that confirm that presence of several functional groups aided to formation of CuONPs. The crystallographic pattern of CuONPs was recorded via X-ray diffraction analysis. Antimicrobial potential of CuONPs was compared to copper acetate and antibiotic/antifungal drug. CuONPs exhibited more inhibition zones against S. aureus (32 ± 0.1 mm), E. coli (36 ± 0.1 mm), S. typhi (27 ± 0.2 mm), E. faecalis (37 ± 0.1 mm), C. albicans (34 ± 0.3 mm) than copper acetate and antibiotic/antifungal drug. Promising MIC values of were recorded against S. aureus, E. coli, and S. typhi. CuONPs at 200 ppm inhibited the growth of C. lunata, F. oxysporium, A. flavus, and Mucor circinelloid with inhibtion of 76.92, 73.33, 63.63, and 53.84%, respectively regarded the control 100% growth. The photocatalytic role of CuONPs was recorded for degradation of reactive red (RR195) and reactive blue (RB) dyes with maximum degradation of 84.66% and 90.82%, respectively at 75 min. Moreover, the optimal dyes degradation was 84.66 and 90.82%, respectively at 40 °C.

Water Purification Using Choline-Amino Acid Ionic Liquids: Removal of Amoxicillin.

Antibiotics are the main active pharmaceutical ingredients (APIs) for the treatment and prevention (prophylaxis) of bacterial infections, for which they are essential for health preservation. However, depending on the target bacterial strain, an efficient treatment may imply weeks of continuous intake of antibiotics, whose unmetabolized fraction ends up in the wastewater system by human and animal excreta. The presence of these chemical compounds in wastewater is known to damage aquatic ecosystems and cause antibiotic resistance of pathogenic agents, which threatens the future application of these medicines. Aqueous two-phase systems (ATPSs), an emergent extraction technology for biomolecules such as proteins and vitamins, could provide more eco-friendly and cost-effective extractive alternatives given their nontoxicity and low energetic requirements. Moreover, choline-amino acid ([Ch][AA]) ionic liquids (also known as CAAILs or ChAAILs) are considered one of the greenest classes of ionic liquids due to their favorable biocompatibility, biodegradability, and ease of chemical synthesis. In this work, partition studies of amoxicillin were performed in three ATPSs containing dipotassium hydrogen phosphate (K2HPO4) and the CAAILs (cholinium l-alaninate, [Ch][Ala]; cholinium glycinate, [Ch][Gly]; and cholinium serinate, [Ch][Ser]) at 298.15 K and 0.1 MPa. To better characterize the extract and reduce errors in quantification, the effect of pH on the intensity and stability of the UV-vis spectra of amoxicillin was studied prior to the partition studies, and computational chemistry was used to validate the molecular structure of the synthesized ionic liquids. During experimental determinations, it was observed that the extraction of amoxicillin was favored by less polar ionic liquids, achieving maximum partition coefficients (K) and extraction efficiencies (E) of K = (16 ± 6)·101 and E / % = 97 ± 2, respectively, for {[Ch][Gly] (1) + K2HPO4 (2) + Water (3)} in the longest tie-line.

The potential biological activities of Aspergillus luchuensis-aided green synthesis of silver nanoparticles.

Biosynthetic metals have attracted global attention because of their safety, affordability, and environmental friendliness. As a consequence, the cell-free filtrate (CFF) of Dill leaf-derived endophytic fungus Aspergillus luchuensis was employed for the extracellularly synthesis silver nanoparticles (AgNPs). A reddish-brown color shift confirmed that AgNPs were successfully produced. The obtained AgNPs were characterized by UV-Vis (ultraviolet-visible spectroscopy), Transmission electron microscopy (TEM), FTIR, EDX, and zeta potential. Results demonstrated the creation of crystalline AgNPs with a spherical shape at 427.81 nm in the UV-Vis spectrum, and size ranged from 16 to 18 nm as observed by TEM. Additionally, the biogenic AgNPs had a promising antibacterial activity versus multidrug-resistant bacteria, notably, S. aureus, E. coli, and S. typhi. The highest growth reduction was recorded in the case of E. coli. Furthermore, the biosynthesized AgNPs demonstrated potent antifungal potential versus a variety of harmful fungi. The maximum growth inhibition was evaluated from A. brasinsilles, followed by C. albicans as compared to cell-free extract and AgNO3. In addition, data revealed that AgNPs possess powerful antioxidant activity, and their ability to scavenge radicals increased from 33.0 to 85.1% with an increment in their concentration from 3.9 to 1,000 μg/mL. Furthermore, data showed that AgNPs displayed high catalytic activity of safranin under light irradiation. The maximum decolorization percentage (100%) was observed after 6 h. Besides, the biosynthesized AgNPs showed high insecticidal potential against 3rd larval instar of Culex pipiens. Taken together, data suggested that endophytic fungus, A. luchuensis, is an attractive candidate as an environmentally sustainable and friendly fungal nanofactory.

SrO–ZnO–PbO–B2O3 glassy insights: Unveiling the structural and optical features for gamma ray shielding efficacy

The melt-quenching approach was utilised to synthesize amorphous SrO–ZnO–PbO–B2O3 glasses, with FTIR spectroscopy applied to the samples to reveal the various bonds' stretching and bending vibrations. With PbO introduced to the network, the UV–Vis absorption spectrum's absorption peak shifts towards the higher wavelength values, while Tauc plot analysis of the UV–Vis spectra reveals a 2.957–2.569 eV decrease in the band gap energy. The radiation shielding properties are examined via Phy-X program. The mass attenuation coefficient (MAC) has an inverse relation with the energy, which demonstrated the greater penetration ability of radiation that contains higher energy. In terms of the MAC values at low energies the results revealed a greater difference, while they are almost identical at higher energies. The linear attenuation coefficient (LAC) was evaluated and the chemical composition's influence discussed, with the LAC values in the order of SZPB1 <SZPB2 <SZPB3 <SZPB4. This confirms that the PbO addition leads to increased LAC values. The half value layer (HVL) decreases with increased concentration of PbO. This suggests that the higher the glass system's PbO content, the thinner the glass system needs to be to attenuate half of the incoming photons.

Study on cultivation of aerobic granular sludge and its application in degrading lignin models in the sequencing batch biofilter granular reactor.

In this study, three sequencing batch biofilter granular reactors (SBBGRs) were employed to treat model lignin wastewater containing different lignin models (2,6-dimethoxyphenol, 4-methoxyphenol, and vanillin). After 40 days of cultivation, uniform-shaped aerobic granular sludge (AGS) was successfully developed through nutrient supplementation with synthetic wastewater. During the acclimation stage, the chemical oxygen demand (COD) reduction efficiencies of the three reactors showed a trend of initial decreasing (5-20%) and then recovering to a high reduction efficiency (exceeding 90%) in a short period of time. During the stable operation stage, all three reactors achieved COD reduction efficiencies exceeding 90%. These findings indicated the cultivated AGS's robust resistance to changes in lignin models in water. UV-Vis spectra analysis confirmed the effective degradation of the three lignin models. Microbiological analysis showed that Proteobacteria and Bacteroidetes were always the dominant phyla. At the genus level, while Acinetobacter (15.46%) dominated in the inoculation sludge, Kapabacteriales (7.93%), SBR1031 (11.77%), and Chlorobium (25.37%) were dominant in the three reactors (for 2,6-dimethoxyphenol, 4-methoxyphenol, and vanillin) after degradation, respectively. These findings demonstrate that AGS cultured with SBBGR effectively degrades lignin models, with different dominant strains observed for various lignin models.

Localized surface plasmon resonance properties of green synthesized Ag/rGO composite nanoparticles utilizing Amaranthus viridis extract for biosensor applications

The green synthesized Ag/rGO composite nanoparticles were successfully synthesized using the Hummers' method with Amaranthus viridis extract. The localized surface plasmon resonance (LSPR) behavior of the Ag/rGO was studied using the Kretschmann configuration consisting of prism/Au/Ag/rGO/air. The addition of the Ag/rGO composite to the prism system aims to determine the effect of rGO on the SPR angle. X-ray diffraction results showed that there were four diffraction peaks with the presence of lattice planes (111), (200), (220), and (311), proving the face-centered cubic crystal structure of silver. The characterization results showed that the size of Ag NPs was 23.1 nm, and that of Ag/rGO composite was 16.7 nm. The EDX results of the Ag/rGO composite showed the presence of several elements such as C, O, Ag, and N. Fourier transform infrared analysis showed the presence of O–H, C–H, CO, CC, and C–O–C functional groups confirming the formation of Ag/rGO. The UV–Vis spectra showed an absorption peak at 257 nm and 346–412 nm with an increase in band gap energy from 3.27 eV to 3.40 eV. Meanwhile, the LSPR measurements demonstrate a shift in the SPR angle due to the addition of rGO, in which the angle shifts from 0.33 ° to 0.96 °. In conclusion, the addition of rGO can optimize the plasmonic properties of Ag, so that it potentially could be applied to enhance the performance of SPR-based biosensor applications.

Rapid and practical colorimetric biosensor for leishmaniasis diseases

In this article, a colorimetric biosensor for detection of Leishmania major surface protease (Gp63) antibody (anti-gp63) was developed by using gold nanoparticle (AuNP) as a color reagent. The dispersion or aggregation of AuNPs leads to a distinct and sensitive change in UV-vis spectra and solution color. For this purpose, kinetoplastid membrane protein-11 (KMP-11) was labeled with AuNPs surface directly. After that, Gp63 antibody was added in the KMP-11@AuNP solution and a color change from red/pink to purple/violet was observed. As a result, anti-gp63 solution diluted at a ratio of 1:640 can be detected with the developed colorimetric leishmania biosensor. The relative standard deviation value for 1:320 diluted anti-gp63 was calculated as 1.29 %. Furthermore, the linear range of the developed colorimetric biosensor was determined as 1:80 to 1:640. Moreover, developed Leishmania biosensor was applied for detection of leishmania parasite crude antigen and rabbit serum which were used as positive and negative samples respectively. As a result, the recovery values for the measurements of aforementioned samples were calculated as 95.3 % ± 0.02, 103.1 % ± 0.02, 96.2 % ± 0.01 and 95.5 % ± 0.03 for dilutions of 1:200, 1:160, 1:320 and 1:640 anti-gp63 solutions respectively.

The potential meat flavoring derived from Maillard reaction products of rice protein isolate hydrolysate-xylose via the regulation of temperature and cysteine

Maillard reaction products (MRPs) derived from rice protein isolate hydrolysate and D-xylose, with or without L-cysteine, were developed as a potential meat flavoring. The combined impact of temperature (80–140 °C) and cysteine on fundamental physicochemical characteristics, antioxidant activity, and flavor of MRPs were investigated through assessments of pH, color, UV–visible spectra, fluorescence spectra, free amino acids, volatile compounds, E-nose, E-tongue, and sensory evaluation. Results suggested that increasing temperature would reduce pH, deepen color, promote volatile compounds formation, and reduce the overall umami and bitterness. Cysteine addition contributed to the color inhibition, enhancement of DPPH radical-scavenging activity and reducing power, improvement in mouthfulness and continuity, reduction of bitterness, and the formation of sulfur compounds responsible for meaty flavor. Overall, MRPs prepared at 120 °C with cysteine addition could be utilized as a potential meat flavoring with the highest antioxidant activity and relatively high mouthfulness, continuity, umami, meaty aroma, and relatively low bitterness.