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Aims: The escalating demands for traditional fossil fuels with unsecured deliverance and issues of climate change compel the researchers to develop alternative fuels like bioethanol. This study examines the prospect of biofuel production from high carbohydrate containing lignocellulosic material, e.g. sugarcane bagasse through biological means. Methodology and Results: Cellulolytic enzymes were collected from the culture filtrate of thermotolerant Trichodermaviride grown on variously pre-treated sugarcane bagasse. CMCase and FPase enzyme activities were determined as a measure of suitable substrate pre-treatment and optimum condition for cellulolytic enzyme production. The highest CMCase and FPase activity was found to be 1.217 U/ml and 0.109 U/ml respectively under the production conditions of 200 rpm, pH 4.0 and 50 °C using steamed NaOH treated bagasse as substrate. SEM was carried out to compare and confirm the activity of cellulolytic enzymes on sugarcane bagasse. Saccharification of pre-treated bagasse was carried out with crude enzymes together using a two-factor experimental design. Under optimized conditions the pre-treated bagasse was saccharified up to 42.7 % in 24 h. The hydrolysate was concentrated by heating to suitable concentration and then used for fermentation by an indigenous isolate of Saccharomyces cerevisiae. With 50 and 80 % brix containing liquor the concentration of alcohol was 0.579 % and 1.15 % respectively. Conclusion, significance and impact of study: This is the first report in Bangladesh for the production of cellulosicethanol using local isolates. Though the rate of alcohol production was very low, a great impetus in this field can maximize the production thereby meet the demand for fuel in future.

A laboratory experiment was carried out to study the ability of soil to adsorption of Zinc added from three sources: nano-Zinc oxide (ZnnO), nano-chelated Zinc (Znn-DTPA), and nano-organic Zinc (Znn-HA), with several concentrations ranging from 0-160 mg Zn kg-1. Zinc was added for each concentration at an amount of 20 ml per 1 gm of soil. As for the ordinary sources, Zinc was added from the ordinary sources, Zinc oxide, ZnO, chelated Zinc , Zn-DTPA, and ordinary organic Zinc , Zn-HA, in several concentrations, ranging from 0-500 mg Zn kg-1. Each concentration was added at 20 ml per 1 gm of soil and two repetitions for each source. The adsorption capacity of the soil and the binding energy of the adsorbed Zinc , and to estimate the thermodynamic parameters for the adsorption of nano-Zinc in desert soils, and Freundlich equations were used to study and evaluate the adsorption process. The thermodynamic parameters Kº, ΔGº, ΔHº, and ΔSº were calculated based on the results of the adsorption experiment. The results of the experiment indicate that both equations succeeded in describing the adsorption of nano and ordinary Zinc depending on the value of the determination coefficient of (R2), which ranged between (0.959 - 0.971) and (0.884 - 0.985) for each of the Langmuir and Freundlich equations respectively. As for the thermodynamic equilibrium constant Kº, it decreased with the increase in the reaction temperature for three sources: Znn-DTPA, ZnO, and Zn-HA, while it increased with the other three sources. The negative ΔGº values for all sources of nano and ordinary Zinc parameters spontaneity of the reaction at both temperatures 25°C - 45°C.

Combining organometallic frameworks with graphene oxide presents a fresh strategy to enhance the electrochemical capabilities of supercapacitors, contributing to the advancement of sustainable energy solutions. Continued refinement of materials and device design holds promise for broader applications across energy storage and conversion systems. This featured application underscores the inventive utilization of organometallic frameworks on graphene oxide, shedding light on the creation of superior energy storage devices for eco-friendly solutions. This review article delves into the synergistic advancements resulting from the fusion of organometallic frameworks with graphene oxide, offering a thorough exploration of their utility in sustainable eco-energy solutions. This review encompasses various facets, including synthesis methodologies, amplified catalytic performances, and structural elucidations. Through collaborative efforts, notable progressions in photocatalysis, photovoltaics, and energy storage are showcased, illustrating the transformative potential of these hybrids in reshaping solar energy conversion and storage technologies. Moreover, the environmentally conscious features of organometallic–graphene oxide hybrids are underscored through their contributions to environmental remediation, addressing challenges in pollutant elimination, water purification, and air quality enhancement. The intricate structural characteristics of these hybrids are expounded upon to highlight their role in tailoring material properties for specific eco-energy applications. Despite promising advancements, challenges such as scalability and stability are candidly addressed, offering a pragmatic view of the current research landscape. The manuscript concludes by providing insights into prospective research avenues, guiding the scientific community towards surmounting hurdles and fully leveraging the potential of organometallic–graphene oxide hybrids for a sustainable and energy-efficient future.

Herein, a new π‐electron‐delocalized building block (ProPh‐4CHO) is reported for the construction of a π‐electron‐extended porphyrin/pyrene‐linked covalent organic framework (ProPh‐PyTA‐COF) for use as a saturable absorber (SA) in a Q‐switched all‐solid‐state laser. Employing a mode‐locked fiber laser operated with 130‐fs pulses at 1030 nm and a repetition rate of 28 MHz, ProPh‐PyTA‐COF exhibits remarkable optical nonlinear absorptions: two saturable absorptions with saturation intensities of 92 MW cm−2 and 1 kW cm−2. This material is used to fabricate the first pulsed Q‐switched all‐solid‐state laser incorporating a COF as an absorber. The laser incorporating this COF‐SA exhibited a pump power of 6.5 W with a pulse duration of 1.2 μs, corresponding to a pulse repetition rate of 94.4 kHz. This study not only reveals the possibility of using saturation absorption to pulse a solid‐state laser but also opens up a new path toward optical nonlinearity through the engineering of π‐bond delocalization.

This study was conducted to assess the bioactive value of Tamarix gallica honey samples collected from three countries. In total, 150 Tamarix gallica honey samples from Saudi Arabia (50), Libya (50), and Egypt (50) were collected and compared, based on the results of the melissopalynological analysis, their physicochemical attributes, antioxidant and antimicrobial activities, and biochemical properties, together with their total phenolic and total flavonoid contents. Depending on the geographical origin, we observed different levels of growth suppression for six resistant bacterial strains. The pathogenic microorganisms tested in this study were Staphylococcus aureus, Streptococcus mutans, Klebsiella pneumoniae, Escherichia coli, Proteus vulgaris, and Pseudomonas aeruginosa. There was a strong correlation between the polyphenol and flavonoid contents, as well as significant (p < 0.05) radical scavenging activities. The melissopalynological analysis and physicochemical properties complied with the recommendation of the Gulf and Egyptian Technical Regulations on honey, as well as the Codex Alimentarius of the World Health Organization and the European Union Normative related to honey quality. It was concluded that Tamarix gallica honey from the three countries has the capacity to suppress pathogenic bacterial growth and has significant radical scavenging activities. Moreover, these findings suggest that Tamarix gallica honey may be considered as an interesting source of antimicrobial compounds and antioxidants for therapeutical and nutraceutical industries or for food manufacturers.

Herein, we report the efficient preparation of π-electron-extended triazine-based covalent organic framework (TFP-TPTPh COF) for photocatalysis and adsorption of the rhodamine B (RhB) dye molecule, as well as for photocatalytic hydrogen generation from water. The resultant TFP-TPTPh COF exhibited remarkable porosity, excellent crystallinity, high surface area of 724 m2 g−1, and massive thermal stability with a char yield of 63.41%. The TFP-TPTPh COF demonstrated an excellent removal efficiency of RhB from water in 60 min when used as an adsorbent, and its maximum adsorption capacity (Qm) of 480 mg g−1 is among the highest Qm values for porous polymers ever to be recorded. In addition, the TFP-TPTPh COF showed a remarkable photocatalytic degradation of RhB dye molecules with a reaction rate constant of 4.1 × 10−2 min−1 and an efficiency of 97.02% under ultraviolet–visible light irradiation. Furthermore, without additional co-catalysts, the TFP-TPTPh COF displayed an excellent photocatalytic capacity for reducing water to generate H2 with a hydrogen evolution rate (HER) of 2712 μmol g−1 h−1. This highly active COF-based photocatalyst appears to be a useful material for dye removal from water, as well as solar energy processing and conversion.

Conjugated microporous polymers (CMPs) represent a promising class of materials with diverse applications due to their unique chemophysical characteristics. We introduce a novel approach for developing a TPPDA–TPA CMP- and TPPDA–ThZ CMP-based dynamic tetraphenyl-p-phenylenediamine (TPPDA) unit employing the optimum conditions for the Suzuki protocol. These CMPs incorporate triphenylamine (TPA) and 4,7-di(thiophen-2-yl)benzo[c]thiadiazole (ThZ), and exhibit distinct electronic properties. Our CMPs demonstrate high thermal durability (char yield up to 69.5 wt%) and significant surface areas (up to 132 m2 g−1). The TPPDA–TPA CMP shows a notable presence of nucleophilic bonding sites, enhancing the selective uptake of CO2, with around twofold-higher CO2 uptake (27.49 cm3 g−1) compared with TPPDA–ThZ CMP (14.67 cm3 g−1). Additionally, we evaluate the selectivity of CO2 over N2 gases on TPPDA CMPs. We analyze CO2 uptake based on key thermodynamic and kinetic principles, including the Clausius–Clapeyron equation and Henry's law. This research offers a promising strategy for enhancing CO2-adsorption capacities on CMPs. [ABSTRACT FROM AUTHOR]

Lately, there has been growing interest in utilizing conjugated microporous polymers (CMPs) as favorable electrodes for storing energy. However, certain synthesized CMPs have exhibited limitations such as depressed conductivity as well as inefficient electrochemical properties, which have hindered their feasible use. In this regard, we effectively synthesized microporous carbonaceous materials via calcination followed by KOH activation processes for both TAT-Cz and TAT-BCz CMPs. The resulting microporous carbons showed noteworthy characteristics, including a significantly large surface area (up to 600 m2 g−1), notable pore volume (reaching 0.75 cm3 g−1), superb thermal stabilization and char yield (up to 791 °C and 90%), and amorphous nature. In particular, the thermal treatment of TAT-Cz CMP at 800 °C produced the TAT-Cz-800, which displayed a remarkable electrochemical capacitance of 1005 F g−1 at 1.0 A g−1 current density. This outstanding capacitance value is comparable to those of other porous carbon materials. Additionally, TAT-Cz-800 demonstrated the best coulombic efficiencies over a span of 5000 cycles at 10 A g−1 reaching 98.59%. Moreover, the excellent energy density for TAT-Cz-800 carbons was determined to be 139.58 W h kg−1 at a power density of 500 W kg−1. Interestingly, a two-electrode symmetric SC holding TAT-Cz-800 displayed a superb electrochemical capacitance of 458 F g−1 at 1.0 A g−1, and a higher energy density up to 63.61 W h kg−1. The exceptional electrochemical efficacy of TAT-Cz-800 as an electrode for energy storage is likely due to its large surface area, highly porous carbon structure, and high degree of nitrogen and oxygen contents. [ABSTRACT FROM AUTHOR]

A laboratory experiment was carried out to study the ability of soil to adsorption of Zinc added from three sources: nano-Zinc oxide (ZnnO), nano-chelated Zinc (Znn-DTPA), and nano-organic Zinc (Znn-HA), with several concentrations ranging from 0-160 mg Zn kg-1. Zinc was added for each concentration at an amount of 20 ml per 1 gm of soil. As for the ordinary sources, Zinc was added from the ordinary sources, Zinc oxide, ZnO, chelated Zinc, Zn-DTPA, and ordinary organic Zinc, Zn-HA, in several concentrations, ranging from 0-500 mg Zn kg-1. Each concentration was added at 20 ml per 1 gm of soil and two repetitions for each source. The adsorption capacity of the soil and the binding energy of the adsorbed Zinc, and to estimate the thermodynamic parameters for the adsorption of nano-Zinc in desert soils, and Freundlich equations were used to study and evaluate the adsorption process. The thermodynamic parameters Kº, ΔGº, ΔHº, and ΔSº were calculated based on the results of the adsorption experiment. The results of the experiment indicate that both equations succeeded in describing the adsorption of nano and ordinary Zinc depending on the value of the determination coefficient of (R² ), which ranged between (0.959 - 0.971) and (0.884 - 0.985) for each of the Langmuir and Freundlich equations respectively. As for the thermodynamic equilibrium constant Kº, it decreased with the increase in the reaction temperature for three sources: Znn-DTPA, ZnO, and Zn-HA, while it increased with the other three sources. The negative ΔGº values for all sources of nano and ordinary Zinc parameters spontaneity of the reaction at both temperatures 25°C - 45°C. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are promising photocatalysts for treating organic pollutants and solar-to-hydrogen conversion; however, their suboptimal energy band structure and rapid charge recombination limit their photocatalytic performance. Herein, we synthesized two donor–acceptor hetero[6]radialene-based TFP 3D COFs, TFP-Py and TFP-BF, with a unique [3,4]-linked ffc topological structure for the adsorptive and photocatalytic degradation of the rhodamine B (RhB) dye and photocatalytic hydrogen production from water. The acceptor is hetero[6]radialene and the donors are planar pyrene (Py) and twisted bifluorenylidene (BF). TFP 3D COFs surpass previously reported COFs in removing RhB from water in 10 min with a maximum adsorption capacity (Qm) of 840 mg g−1. Interestingly, the incorporation of the twisted BF structure into the hetero[6]radialene-based 3D COF backbone improved the band gap structure, charge transport, and photoinduced electron and hole isolation. The TFP-BF 3D COF degrades organic dye (RhB) with 1.4-fold greater catalytic activity (1.5 × 10−2 min−1) than the planar pyrene donor-derived TFP-Py 3D COF (1.1 × 10−2 min−1). It demonstrates a hydrogen evolution (HER) rate of 21.04 mmol g−1 h−1, obviating the need for a Pt cocatalyst, the highest COF-specific capacity ever recorded. This study illuminates how electron donor topology and hetero[6]radialene 3D structure affect photocatalysis. [ABSTRACT FROM AUTHOR]

Combining organometallic frameworks with graphene oxide presents a fresh strategy to enhance the electrochemical capabilities of supercapacitors, contributing to the advancement of sustainable energy solutions. Continued refinement of materials and device design holds promise for broader applications across energy storage and conversion systems. This featured application underscores the inventive utilization of organometallic frameworks on graphene oxide, shedding light on the creation of superior energy storage devices for eco-friendly solutions. This review article delves into the synergistic advancements resulting from the fusion of organometallic frameworks with graphene oxide, offering a thorough exploration of their utility in sustainable eco-energy solutions. This review encompasses various facets, including synthesis methodologies, amplified catalytic performances, and structural elucidations. Through collaborative efforts, notable progressions in photocatalysis, photovoltaics, and energy storage are showcased, illustrating the transformative potential of these hybrids in reshaping solar energy conversion and storage technologies. Moreover, the environmentally conscious features of organometallic–graphene oxide hybrids are underscored through their contributions to environmental remediation, addressing challenges in pollutant elimination, water purification, and air quality enhancement. The intricate structural characteristics of these hybrids are expounded upon to highlight their role in tailoring material properties for specific eco-energy applications. Despite promising advancements, challenges such as scalability and stability are candidly addressed, offering a pragmatic view of the current research landscape. The manuscript concludes by providing insights into prospective research avenues, guiding the scientific community towards surmounting hurdles and fully leveraging the potential of organometallic–graphene oxide hybrids for a sustainable and energy-efficient future. [ABSTRACT FROM AUTHOR]

The current investigation was conducted to assess the melissopalynological, physicochemical, and biochemical properties, antimicrobial and antioxidant activities as well as total phenolic and total flavonoid contents of 794 Sidr honey samples collected from the Saudi market that had been imported from 12 different countries. Testing Sidr honey from different countries showed different levels of growth suppression observed against five drug resistant bacterial strains. The pathogenic strains were Staphylococcus aureus, Streptococcus mutans, Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa. The antimicrobial activity showed growth suppression levels which varied according to the origin of the honey. The comparative study of Sidr honeys revealed a strong correlation between total polyphenol and flavonoid contents and significant radical scavenging activities in particular Egyptian and Saudi Arabian honeys. The melissopalynological and physicochemical properties of different Sidr honeys complied with the recommendations of the WHO Codex Alimentarius, the European Union standards for honey quality, and the Gulf Technical Regulation on honey (GSO 147:2008-Standards Store-GCC Standardization Organization). It was concluded that Sidr honey from different geographical areas has the capacity to suppress the growth of pathogenic bacteria and perform significant radical scavenging activities.

In this study, we prepared a difunctionalized cyanate ester double-decker silsesquioxane (DDSQ-OCN) cage with a char yield and thermal decomposition temperature (Td) which were both much higher than those of a typical bisphenol A dicyanate ester (BADCy, without the DDSQ cage) after thermal polymerization. Here, the inorganic DDSQ nanomaterial improved the thermal behavior through a nano-reinforcement effect. Blending the inorganic DDSQ-OCN cage into the epoxy resin improved its thermal and mechanical stabilities after the ring-opening polymerization of the epoxy units during thermal polymerization. The enhancement in the physical properties arose from the copolymerization of the epoxy and OCN units to form the organic/inorganic covalently bonded network structure, as well as the hydrogen bonding of the OH groups of the epoxy with the SiOSi moieties of the DDSQ units. For example, the epoxy/DDSQ-OCN = 1/1 hybrid, prepared without Cu(II)-acac as a catalyst, exhibited a glass transition temperature, thermal decomposition temperature (Td), and char yield (166 °C, 427 °C, and 51.0 wt%, respectively) that were significantly higher than those obtained when applying typical organic curing agents in the epoxy resin. The addition of Cu(II)-acac into the epoxy/BADCy and epoxy/DDSQ-OCN hybrids decreased the thermal stability (as characterized by the values of Td and the char yields) because the crosslinking density and post-hardening also decreased during thermal polymerization; nevertheless, it accelerated the thermal polymerization to a lower curing peak temperature, which is potentially useful for real applications as epoxy molding compounds.

Covalent organic frameworks (COFs) have attracted significant interest because of their heteroatom-containing architectures, high porous networks, large surface areas, and capacity to include redox-active units, which can provide good electrochemical efficiency in energy applications. In this research, we synthesized two novel hydroxy-functionalized COFs—TAPT-2,3-NA(OH)2, TAPT-2,6-NA(OH)2 COFs—through Schiff-base [3 + 2] polycondensations of 1,3,5-tris-(4-aminophenyl)triazine (TAPT-3NH2) with 2,3-dihydroxynaphthalene-1,4-dicarbaldehyde (2,3-NADC) and 2,6-dihydroxynaphthalene-1,5-dicarbaldehyde (2,6-NADC), respectively. The resultant hydroxy-functionalized COFs featured high BET-specific surface areas up to 1089 m2 g–1, excellent crystallinity, and superior thermal stability up to 60.44% char yield. When used as supercapacitor electrodes, the hydroxy-functionalized COFs exhibited electrochemical redox activity due to the presence of redox-active 2,3-dihydroxynaphthalene and 2,6-dihydroxynaphthalene in their COF skeletons. The hydroxy-functionalized COFs showed specific capacitance of 271 F g−1 at a current density of 0.5 A g−1 with excellent stability after 2000 cycles of 86.5% capacitance retention. Well-known pore features and high surface areas of such COFs, together with their superior supercapacitor performance, make them suitable electrode materials for use in practical applications.

Propolis, a resin produced by honeybees, has long been used as a dietary supplement and folk remedy, and more recent preclinical investigations have demonstrated a large spectrum of potential therapeutic bioactivities, including antioxidant, antibacterial, anti-inflammatory, neuroprotective, immunomodulatory, anticancer, and antiviral properties. As an antiviral agent, propolis and various constituents have shown promising preclinical efficacy against adenoviruses, influenza viruses, respiratory tract viruses, herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), human immunodeficiency virus (HIV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Over 300 chemical components have been identified in propolis, including terpenes, flavonoids, and phenolic acids, with the specific constituent profile varying widely according to geographic origin and regional flora. Propolis and its constituents have demonstrated potential efficacy against SARS-CoV-2 by modulating multiple pathogenic and antiviral pathways. Molecular docking studies have demonstrated high binding affinities of propolis derivatives to multiple SARS-CoV-2 proteins, including 3C-like protease (3CLpro), papain-like protease (PLpro), RNA-dependent RNA polymerase (RdRp), the receptor-binding domain (RBD) of the spike protein (S-protein), and helicase (NSP13), as well as to the viral target angiotensin-converting enzyme 2 (ACE2). Among these compounds, retusapurpurin A has shown high affinity to 3CLpro (ΔG = −9.4 kcal/mol), RdRp (−7.5), RBD (−7.2), NSP13 (−9.4), and ACE2 (−10.4) and potent inhibition of viral entry by forming hydrogen bonds with amino acid residues within viral and human target proteins. In addition, propolis-derived baccharin demonstrated even higher binding affinity towards PLpro (−8.2 kcal/mol). Measures of drug-likeness parameters, including metabolism, distribution, absorption, excretion, and toxicity (ADMET) characteristics, also support the potential of propolis as an effective agent to combat COVID-19.

Aim: The aim of this study was to investigate the potential antibacterial activity of some Saudi Arabia honey against selected bacterial strains of medical importance. Materials and Methods: A total of 10 Saudi Arabia honey used to evaluate their antimicrobial activity against some antibiotic-resistant pathogenic bacterial strains. The bacterial strains were Staphylococcus aureus, Streptococcus pyogenes, Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa. Results: The antibacterial activity of Saudi honey against five bacterial strains showed different levels of inhibition according to the type of honey. The overall results showed that the potential activity was differing according to the pathogen and honey type. Conclusion: It could be concluded that the Saudi honey inhibit the growth of bacterial strains and that honey can be used as complementary antimicrobial agent against selected pathogenic bacteria.

Porous organic polymers have been received considerable attention due to their heteroatom-containing structures and high surface areas, which can offer high electrochemical performance in energy applications. The majority of reported Tröger’s base-functionalized porous organic polymers have been applied as effective candidates for sensing and gas separation/adsorption, while their use as electrode materials in supercapacitors is rare. Here, a novel covalent microporous organic polymer containing carbazole and Tröger’s base CzT-CMOP has been successfully synthesized through the one-pot polycondensation of 9-(4-aminophenyl)-carbazole-3,6-diamine (Cz-3NH2) with dimethoxymethane. The polycondensation reaction’s regioselectivity was studied using spectroscopic analyses and electronic structure calculations that confirmed the polycondensation occurred through the second and seventh positions of the carbazole unit rather than the fourth and fifth positions confirmed by first-principles calculations. Our CzT-CMOP exhibited high thermal stability of approximately 463.5 °C and a relatively high Brunauer–Emmett–Teller surface area of 615 m2 g−1 with a nonlocal density functional theory’s pore size and volume of 0.48 cm3 g−1 and 1.66 nm, respectively. In addition, the synthesized CzT-CMOP displayed redox activity due to the existence of a redox-active carbazole in the polymer skeleton. CzT-CMOP revealed high electrochemical performance when used as active-electrode material in a three-electrode supercapacitor with an aqueous electrolyte of 6 M KOH, and it showed specific capacitance of 240 F g−1 at a current density of 0.5 A g−1 with excellent stability after 2000 cycles of 97% capacitance retention. Accordingly, such porous organic polymer appears to have a variety of uses in energy-related applications.

Wasps, members of the order Hymenoptera, are distributed in different parts of the world, including Brazil, Thailand, Japan, Korea, and Argentina. The lifestyles of the wasps are solitary and social. Social wasps use venom as a defensive measure to protect their colonies, whereas solitary wasps use their venom to capture prey. Chemically, wasp venom possesses a wide variety of enzymes, proteins, peptides, volatile compounds, and bioactive constituents, which include phospholipase A2, antigen 5, mastoparan, and decoralin. The bioactive constituents have anticancer, antimicrobial, and anti-inflammatory effects. However, the limited quantities of wasp venom and the scarcity of advanced strategies for the synthesis of wasp venom’s bioactive compounds remain a challenge facing the effective usage of wasp venom. Solid-phase peptide synthesis is currently used to prepare wasp venom peptides and their analogs such as mastoparan, anoplin, decoralin, polybia-CP, and polydim-I. The goal of the current review is to highlight the medicinal value of the wasp venom compounds, as well as limitations and possibilities. Wasp venom could be a potential and novel natural source to develop innovative pharmaceuticals and new agents for drug discovery.