Current Research in Green and Sustainable Chemistry最新文献

Electrocarboxylation reactions hold significant promise as a sustainable and efficient method for carbon-carbon bond formation driven by electricity enabling the direct conversion of carbon dioxide (CO₂) into valuable organic compounds. Despite the potential and advantages of electrocarboxylation reactions over traditional methods, there are still challenges to address for their widespread implementation. In this contribution, our objective is to shed light on the role of these reactions in recycling and converting CO₂ into valuable chemicals. Specifically, we focus on exploring potential correlations between the performance of CO₂-based carboxylation and the choice of working electrode material in combination with the functional groups present in the substrates.

The contribution of plastic packaging in food is substantial, but issues associated with its biodegradability and recycling initiates major concerns for environment and human health thus necessitating substitution of conventional synthetic plastics with bio-based packaging materials. Studies have demonstrated economic competition of bio-based materials with synthetic plastics because of their biodegradability, wide availability, excellent barrier and mechanical properties. These materials can be commercialized on a large scale but still somehow are under-investigated in many areas. Moreover, some of the influencing factors including confusion between bio-based and biodegradability pose a significant challenge on evolution of bio-based packaging. Therefore, the review focuses on bio-based packaging materials derived from various renewable resources like biomass, microorganisms and microalgae involving their possible food packaging applications along with required development in multiple regions for proper utilization of offered advantages in the food packaging market.

Manganese oxide nanoparticles (MnO₂ NPs) were synthesized through a simple one-pot green synthesis method using Saraca asoca leaves extract (SA-MnO₂ NPs), and their physicochemical properties were characterized using various analytical techniques, including electron microscopy (FESEM and TEM), X-ray diffraction (XRD), and electron diffracted X-ray spectroscopy (EDAX). The as-synthesized MnO₂ NPs had a highly crystalline structure with a calculated crystalline size of approximately 18 nm and a d-spacing value of 0.216 nm. The morphology of the SA-MnO₂ NPs was like stacked cubes with high elemental purity, as confirmed by the EDAX spectrum. Further, confirming the as-obtained crystalline size and d-spacing value from the XRD analysis, the samples were subjected to anti-cancer activities to evaluate their reactance against cancer cell lines. The in vitro anti-cancer activity of the synthesized material was assessed against two breast cancer cell lines, namely MCF7 and MDA-MB-231. The results showed that SA-MnO₂ NPs exhibited significantly lower levels of cytotoxicity against these cell lines, indicating their potential as an effective anticancer agent. Further, the IC₅₀ value of SA-MnO₂ NPs at 24 h was greater than 20 μg/mL. Therefore, the synthesized SA-MnO₂ NPs could be a promising candidate for developing novel breast cancer treatment therapies.

In the present study, phycoerythrin pigment protein was extracted and purified from Gracilaria corticata (marine macroalga). The concentration of phycoerythrin (PE) obtained from G. corticata was 0.15 ​mg/ml (fresh weight). In this study, phycoerythrin expressed less antimicrobial activity against pathogens but found effective in total antioxidant activity (264.90 ​± ​10.20 ​μg/ml), DPPH scavenging effect (22.91 ​± ​1.90%) and ferrous ion chelating ability (26.06 ​± ​1.60%). Further, the cytotoxicity assay of PE using colon cancer cells such as SW620 and HCT-116 was tested. Different concentrations (2, 4, 8, 16, 32 ​μl) of phycoerythrin was tested in MTT assay after 24 ​h and 48 ​h incubation. The MTT assay concludes that increasing concentration of phycoerythrin (4.8 ​μg) decreases the cell viability to 42% after 48 ​h in SW 620 ​cell line. Whereas in the HCT 116 ​cell line the increasing concentration of phycoerythrin induces the cell growth on 24 ​h but later drastically reduced growth of cell line (39%) was observed after 48 ​h time in 4.8 ​μg of PE. From this preliminary study, the phycoerythrin pigment extracted from Gracilaria corticata proved to be a potential molecule of interest for cancer studies and diagnosis.

The textile business is one of the most hazardous industries since it produces several chemicals, such as dyes, which are released into water streams with ef-fluents. For the survival of the planet's life and the advancement of humanity, water is a crucial resource. One of the anthropogenic activities that pollute and consume water is the textile industry. Thus, the purpose of the current effort is to Apply coagulation as a Physico-chemical and biological treatment strat-egy with different techniques and mechanisms to treat the effluent streams of textile industries. The discharge of these effluents has a negative impact on the environment, marine life, and human health. Therefore, the treatment of these effluents before discharging is an important matter to reduce their adverse ef-fect. Many physico-chemical and biological treatment strategies for contaminants removal from polluted wastewater have been proposed. Coagulation is thought to be one of the most promising physico-chemical strategies for removing con-taminants and colouring pollutants from contaminated water. Coagulation is accompanied by a floculation process to aid precipitation, as well as the collection of the created sludge following the treatment phase.. Different commercial, and natural coagulants have been applied as a coagulants in the process of coagulation. Additionally, many factors such as; pH, coagulant dose, pollu-tants concentration are optimized to obtain high coagulants removal capacity. This review will discuss the coagulation process, coagulant types and aids in addition to the factors affecting the coagulation process. Additionally, a brief comparison between the coagulation process, and the other processes; princi-ple, advantages, disadvantages, and their efficiency were discussed throgh the review. Furthermore, it discusses the models and optimization techniques used for the coagulation process including response surface methodology (RSM), ar-tificial neural network (ANN), and several metaheuristic algorithms combined with ANN and RSM for optimization in previous work. The ANN model has more accurate results than RSM. The ANN combined with genetic algorithm gives an accurate predicted optimum solution.

We present a facile and economical method for synthesizing aromatic carboxylic acid derivatives through direct electrochemical C(sp²)–H carboxylation of (hetero)arenes with CO₂. The reaction is carried out using a graphite felt anode and a nickel foam cathode in a user-friendly undivided cell setup under constant current conditions. Corresponding methyl carboxylates are obtained smoothly with good site-selectivity without the need of harsh chemical reductants or toxic transition metal catalysts. A cyclic voltammetry study was conducted, to distinguish between two potential mechanistic pathways. Additionally, nBu₄NI was identified to serve as both electrolyte and anodic mediator. Notably, the methodology allows direct access to the desired product in a scale up manner.

The processing of biomass into biofuels has become an increasingly attractive option as a tool against climate change. One of the most relevant technologies is hydrothermal liquefaction, since it allows processing biomass with high water content without the need for prior drying, obtaining as a product a biocrude oil with high energy densification, lower density, and lower heteroatom content compared to other processes such as pyrolysis. In addition, its operating conditions are moderate, with pressure ranges of 100 to 200 bar and temperatures of 200 to 400 °C, which are much less drastic conditions than gasification and methanation, competing technologies in the transformation and valorization of biomasses for fuel production. Therefore, this article reviews the current state of research on the hydrothermal liquefaction process through of a bibliometric analysis with scientometric parameters that show the growing interest, the collaboration between countries, the evolution, and trends in research topics.

Excessive levels of Fluoride in water is detrimental to human health as it can cause many health problems including both dental and skeletal fluorosis etc. The aims of the current research work were to prepare a novel check the efficiency of Mango (Mangifera indica) leaves powder (MLP) for fluoride removal as well as to observe the effect of various factors over fluoride adsorption from water. The experiments were performed under batch mode and the results indicated that maximum adsorption efficiency was noticed in the acidic range. The Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) techniques were applied for adsorbent characterization. Data modeling declared that pseudo second order kinetic model and Langmuir isotherm models were in best fitting. The study concluded that the investigated adsorbent material is suitable for reducing the high fluoride concentration in water to the WHO established level and is suggested as an ecofriendly material for water purification. Conclusively, future research prospects and further modification of mango leaves materials for fluoride adsorption are recommended.

Chromium (Cr) the most widespread metal is generally found in rocks, animals and plants, while its entrance to the environment occurs from industrial processes e.g. oxidative dyeing, steel works, tanning industries, and chemical industries etc. The study aims were Graphene oxide nanoparticles (GO-NPs) preparation and its evaluation for chromium six (Cr⁺⁶) removal from water as well as the assessment of the effect of various factors (pH, temperature, contact time etc) over Cr⁺⁶ adsorption. The target adsorbent was prepared by Modified Hummer's method and then it was treated with sodium borohydride (NaBH₄) for the synthesis of GO-NPs. The characterization was done by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The results indicated that highest removal (92%) was observed at pH 3 and it was concluded that the nanoparticles were efficient for Cr⁺⁶ adsorption from water. The research work was productive in estimation and optimization of different parameters for the removal of Cr⁺⁶ by GO-NPs. Further chemical modification and activation of the adsorbent is recommended.

Polyglycerol sebacate (PGS) is elastomeric biodegradable polymer with potential biomedical and green packaging applications. This study focuses on the synthesis of vitrimer-like PGS utilizing various catalysts, including Zinc acetate, Zinc oxide and Amberlyst-15. The investigation of vitrimer-like of PGS polymer by polycondensation of glycerol and sebacic acid with various molar ratio of 1:1, 1:1.25 and 1:1.5 will be studied. The synthetic time and temperature were controlled at 72 h, 120 ^°C, respectively. The prepolymer of PGS had a weight-average molecular weight (Mw.) of 1743. The result of functional group was confirmed by Fourier transforms Infrared spectroscopy (FTIR). The intense CO stretch at 1737 cm⁻¹ confirms the formation of ester bonds. The intense OH stretch at 3454 cm⁻¹ indicated hydroxyl groups from hydrogen bonded. When the quantity of catalyst is increased, the results of hardness are rising but swelling (%) becomes lower. The results showed a polymer network has higher cross-link when the catalyst increases. In addition, the proton nuclear magnetic resonance spectroscopy (¹H NMR) analysis found that PGS using catalyst does not have peaks of glycerol.