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The primary aim of this work is to synthesize photocatalyst to promote the synthesis of ynones. In this context, we synthesized AgNPs@g−C3N4 nanocomposite. The nanocomposite was characterized by using SEM, HR‐TEM, XRD, EDS, ICP‐AES, UV‐Vis DRS, XPS, PL and FT‐IR. From the results of characterization, it was transpired that the AgNPs anchored firmly on the carbon nitride sheet and the size of nanoparticles ranges between 2–6 nm. We utilized the photoactive nanocomposite for the synthesis of various substituted ynones under visible light irradiation. Excellent yields were generated for the various substituted ynones (74–84 %). Furthermore, we study the gram scale synthesis and achieved yield up to 78 %. Recyclability of the nanocomposite was also studied and found that the material was recyclable up to 4 times without any significant loss in its activity. We have used 80 W tungsten bulb (λ>420 nm) as the light source and GVL (gamma Valero lactone) as the solvent which proves the process much greener as compared to the conventional methods. [ABSTRACT FROM AUTHOR]

Green chemical approach has been developed by using ionic liquid [MIM-H] CCl3 and TiO2 nanoparticles (NPs) for the synthesis of 3,4-dihydropyrimidine-2(1H)-one (DHPMs) derivatives 4a-r. The formed compounds have been characterised by IR, ¹H and 13C NMR and mass spectrometry. [ABSTRACT FROM AUTHOR]

Hydrogen is recognized as the green energy with the greatest potential for future development, but currently, China's hydrogen production is highly dependent on raw fossil materials, which conflicts with the original intention of developing hydrogen energy. As the abandoned hydropower problem in Southwestern China is serious. The current strategy can be focused using surplus hydropower to produce hydrogen in a green way. In this study, the technical cost and advantage of hydrogen produced using surplus hydropower using the levelized cost of energy model was analyzed. The results show that cheap surplus hydropower will considerably reduce the cost of hydrogen produced using electrolyzing water, and the cost is comparable to that of coal gasification hydrogen production. The hydropower to be abandoned by Southwestern China annually can drive the hydrogen production with 1.2 million tons per year, providing a technically and economically feasible approach to developing hydrogen energy. [ABSTRACT FROM AUTHOR]

In this study, a green, simple and economical approach was used to synthesise the SiO2 @ZnO@Xanthan nanocomposite (NC) to modify the rheological and filtration characteristics of the water‐based drilling mud. The green synthesised NCs were identified using scanning electron microscopy, energy dispersive X‐ray spectroscopy, elemental mapping, X‐ray diffraction and UV–Vis analytical techniques. Additionally, the effect of SiO2 @ZnO@Xanthan NCs on the filtration and rheological properties of mud including apparent viscosity, plastic viscosity, yield point, gel strength, mud cake and fluid loss was investigated. The obtained results confirmed that the synthesised NCs effectively improved the rheological properties of drilling mud, and considerably decreased its fluid loss and filter cake by about 54 and 92.5%, respectively. The results highly recommend the SiO2 @ZnO@Xanthan NC as an excellent additive to improve the rheological properties, and reduce the fluid loss and the filter cake of the drilling mud. [ABSTRACT FROM AUTHOR]

The flower like TiO 2 nanoparticles have been identified as potential electrode material for efficient next generation electrochemical energy storage devices. The present work reports, a novel green approach to synthesize high surface area TiO 2 nanoparticles using medicinal plant leaf extracts namely Ocimum Tenuiflorum Plant and Calotropis Gigantea Plant. The TiO 2 nanoparticles synthesized using Calotropis Gigantea plant confirmed rutile phase from X-ray powder diffraction and Raman spectra. The fourier transform infrared spectroscopy spectra of the sample indicate the presence of TiO 2 vibrational bonds. The field emission scanning electron microscopy images revealed that the flower like shape of nano-granules with an average granule size of 200 nm. The presence of Ti and O elements qualitatively confirmed using energy dispersive spectroscopy spectra, which shows the good stoichiometry in the sample. The flower like shapes with nano petals were further disclosed with the help of high resolution transmission electron microscopy. The corresponding optical band gap was observed to be 3.0 eV. The electrochemical investigations of the sample exhibited a high specific capacitance of 224 F g-1 at 0.5 A g-1 with 71% of capacitive retention after 5000 cycles. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • First report on pentacyclic triterpenoids in Indian Swertia from Western Himalayas. • A validated and simultaneous high-performance thin-layer chromatography was performed. • Microwave, heat reflux and Soxhlet extractions were carried out for the triterpenoids. • Microwave coupled with aqueous ethanol was the most efficient method for extraction. • S. paniculata showed promise to substitute S. chirata in triterpenoid content. Abstract Swertia chirata (Family: Gentianaceae) is a potent and valuable medicinal herb used in various herbal formulations in Indian system of medicine. Different species of Swertia are being used as constituents in various herbal formulations. Present study was undertaken for the screening of an efficient extraction technique and for the development of a rapid and simultaneous quantification of four pentacyclic triterpenoids in different populations of Swertia species by a high-performance thin-layer chromatography (HPTLC)-densitometric method. This method involved the separation of four triterpenoids with a single mobile phase composition consisting of n-hexane, ethyl acetate, toluene (14.2, 4, 1.8 v/v). The retention factor (R f) values for oleanolic acid (OA), ursolic acid (UA), betulinic acid (BA), and lupeol (Lup) were 0.25, 0.50, 0.58 and 0.74 respectively. In this study, microwave assisted extraction (MAE) using aqueous ethanol proved to be the most efficient method for extraction for all the studied triterpenoids when compared with the other conventional methods. The present HPTLC method was found to be precise, fast, and cost effective and can be used for the quality control of any Swertia samples with regards to its pentacyclic triterpenoids content. Since, S. chirata is a critically endangered species, the present study depicts the utility of other species of Swertia viz. S. paniculata and S. angustifolia as promising substitutes for S. chirata in herbal preparations. [ABSTRACT FROM AUTHOR]

Bacterial cellulose has garnered remarkable interest from researchers, particularly those working in the biomedical field. In this work, BC microfibers were fabricated via green dissolution (ZnCl 2) and regeneration (ethanol). The orientation of cellulose chains was investigated during extrusion and simple post-processing via polarized optical microscopy and small-angle X-ray scattering. The results implied that the mechanical properties of BC microfibers can be tuned by rational pre-stretching. The BC microfibers can be programmable, and be used to suture hard or soft tissues. The as-designed paralleled BC microfibers have good biocompatibility and can regulate the directional growth of cells on their surface. The as-obtained BC microfiber with a high tensile strength of up to ∼115 MPa is suitable for surgical sutures. The tunable BC microfibers may be utilized as an adequate fiber-derived biomedical material product. [ABSTRACT FROM AUTHOR]

• Green synthesis of bimetallic CuO-NiO-HNT composites using non-conventional method. • XRD, FT-IR, UV–Vis-DRS, EIS, TEM, AFM and BET were studied to determine the properties of 20CN-HNT composite. • Photocatalytic experiment was done for the synthesized composites against a dye and a drug. • 20 % loading exhibited higher removal efficiency of pollutants compared to other composites. • 20CN-HNT composite revealed good stability and reusability even after 5 cycles. The current study demonstrates the synthesis of one dimensional halloysite nanotube (HNT) based CuO-NiO (CN) photocatalyst using green approach via non-conventional microwave and ultrasonication method. Structural, optical, electrochemical, morphological, stability, and surface area characteristics of the synthesised composite were investigated. From the optical studies, the composite exhibited the absorption band edge above 420 nm in the visible region. Electrochemical studies confirmed that 20CN-HNT composited had good charge carrier separation rate compared to CN. Morphological and elemental analysis revealed that the composite was in microsphere structure with even distribution of elements throughout the composite. Congo red (CR- a dye) and tetracycline (TC- a drug) were used to test the composites' photocatalytic efficacy by the irradiation of visible light. Amongst various synthesized composites, 20CN-HNT composite showed good removal efficiency around 82 % and 84 % against CR and TC respectively, in 90 min. The breakdown of CR and TC is caused by the active species •OH and •O 2 – radicals which was identified using trapping studies. The reusability study demonstrated that the 20CN-HNT photocatalyst retained its high level of stability after being used for five times. [Display omitted] [ABSTRACT FROM AUTHOR]

Context: Marrubium vulgare Linn (Lamiaceae) was generally extracted by conventional methods with low yield of marrubiin; these processes were not considered environment friendly. Objective: This study extracts the whole plant of M. vulgare by microwave assisted extraction (MAE) and optimizes the effect of various extraction parameters on the marrubiin yield by using Central Composite Design (CCD). Materials and methods: The selected medicinal plant was extracted using ethanol: water (1:1) as solvent by MAE. The plant material was also extracted using a Soxhlet and the various extracts were analyzed by HPTLC to quantify the marrubiin concentration. Results: The optimized conditions for the microwave-assisted extraction of selected medicinal plant was microwave power of 539 W, irradiation time of 373 s and solvent to drug ratio, 32 mL per g of the drug. The marrubiin concentration in MAE almost doubled relative to the traditional method (0.69 ± 0.08 to 1.35 ± 0.04%). The IC50 for DPPH was reduced to 66.28 ± 0.6 μg/mL as compared to conventional extract (84.14 ± 0.7 μg/mL). The scanning electron micrographs of the treated and untreated drug samples further support the results. Discussion and conclusion: The CCD can be successfully applied to optimize the extraction parameters (MAE) for M. vulgare. Moreover, in terms of environmental impact, the MAE technique could be assumed as a ‘Green approach’ because the MAE approach for extraction of plant released only 92.3 g of CO2 as compared to 3207.6 g CO2 using the Soxhlet method of extraction.

Shazia Bano,1–3 Samina Nazir,2 Alia Nazir,1 Saeeda Munir,3 Tariq Mahmood,2 Muhammad Afzal,1 Farzana Latif Ansari,4 Kehkashan Mazhar3 1Department of Physics, The Islamia University of Bahawalpur, Bahawalpur, 2Nanosciences and Technology Department, National Centre for Physics, 3Institute of Biomedical and Genetic Engineering (IBGE), 4Pakistan Council for Science and Technology, Islamabad, Pakistan Abstract: Superparamagnetic iron oxide nanoparticles (SPIONs) have the potential to be used as multimodal imaging and cancer therapy agents due to their excellent magnetism and ability to generate reactive oxygen species when exposed to light. We report the synthesis of highly biocompatible SPIONs through a facile green approach using fruit peel extracts as the biogenic reductant. This green synthesis protocol involves the stabilization of SPIONs through coordination of different phytochemicals. The SPIONs were functionalized with polyethylene glycol (PEG)-6000 and succinic acid and were extensively characterized by X-ray diffraction analysis, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, atomic force microscopy, Rutherford backscattering spectrometry, diffused reflectance spectroscopy, fluorescence emission, Fourier-transform infrared spectroscopy, ultraviolet-visible spectroscopy, and magnetization analysis. The developed SPIONs were found to be stable, almost spherical with a size range of 17–25 nm. They exhibited excellent water dispersibility, colloidal stability, and relatively high R2 relaxivity (225 mM-1 s-1). Cell viability assay data revealed that PEGylation or carboxylation appears to significantly shield the surface of the particles but does not lead to improved cytocompatibility. A highly significant increase of reactive oxygen species in light-exposed samples was found to play an important role in the photokilling of human cervical epithelial malignant carcinoma (HeLa) cells. The bio-SPIONs developed are highly favorable for various biomedical applications without risking interference from potentially toxic reagents. Keywords: green approach, biocompatible, multifunctional, bio synthesis, surface modification, microwave incubation, MRI contrast agent, photosensitive SPIONs

Compounds containing triazole have many significant applications in the dye and ink industry, corrosion inhibitors, polymers, and pharmaceutical industries. These compounds possess many antimicrobial, antioxidant, anticancer, antiviral, anti-HIV, antitubercular, and anticancer activities. Several synthetic methods have been reported for reducing time, minimizing synthetic steps, and utilizing less hazardous and toxic solvents and reagents to improve the yield of triazoles and their analogues synthesis. Among the improvement in methods, green approaches towards triazole forming biologically active compounds, especially anticancer compounds, would be very important for pharmaceutical industries as well as global research community. In this article, we have reviewed the last five years of green chemistry approaches on click reaction between alkyl azide and alkynes to install 1,2,3-triazole moiety in natural products and synthetic drug-like molecules, such as in colchicine, flavanone cardanol, bisphosphonates, thiabendazoles, piperazine, prostanoid, flavonoid, quinoxalines, C-azanucleoside, dibenzylamine, and aryl-azotriazole. The cytotoxicity of triazole hybrid analogues was evaluated against a panel of cancer cell lines, including multidrug-resistant cell lines., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

In this study, we explored the catalyst‐free one‐pot multi‐component synthesis of 1,4‐dihydropyridine derivatives by following green chemistry protocol. The present approach shows the significant outcomes such as yield up to 94%, catalyst‐free reaction, easy workup procedure and shorter period of reaction time. In this work we also highlighted the comparison of the yields obtained under both neat and solvent media as well. The anti‐proliferative activity of all newly synthesized compounds has been assessed against six human solid tumor cell lines. Seven compounds show good activity against single cell line whereas, compounds having a pyridine scaffold showed significant anti‐proliferative activity. An expedient synthesis of 1,4‐dihydropyridines (DHPs) and pyridines under catalyst‐free condition is explored with excellent reaction yield up to 94%. All newly synthesized compounds were screened for anti‐proliferative activity against different human tumor cell lines. The remarkable results on yield, process, development of DHPs, anti‐proliferative activity, structure determination and single crystal study of DHPs discussed in this article. [ABSTRACT FROM AUTHOR]

This paper aims to solve the problem of how to quantify the impact of mitigation strategies on carbon emissions from port operations and shipping inside container terminals without real energy consumption data. In order to cope with complex stochastic processes in container terminals, the problem is carried out by establishing a carbon emission quantification simulation model. Firstly, the carbon emission formulation and mitigation strategies are introduced. Then, a container terminal operation simulation model is constructed considering four kinds of mitigation strategies as inputs: reduced speed in waterway channels, reduced auxiliary time at berth, on-shore power supply and alternative fuels, and increased working efficiency of port equipment. Finally, based on a real container terminal, this paper carried out a variety of simulation experiments and discovered that (1) Reduced speed from 24 to 8 knots can achieve a 48.4% reduction of carbon emissions from ships in waterway channels, and 32.9% from the whole container terminal. (2) Compared with diesel in waterway channels and at berth, the use of LNG can reduce carbon emissions by about 11% for the emissions from ships and 8% for the total emissions. [ABSTRACT FROM AUTHOR]

Abstract In this work, we have successfully synthesized highly biocompatible and functionalized B. cristata mediated silver nanoparticles (Ag NPs) with different quantities of its extract for the estimation of impact of defects and the antibacterial activity. The properties of synthesized Ag NPs with B. cristata leaf extract was subjected into various studies such as structural, optical, spectral, surface morphological and antibacterial activities. XRD analysis reveals the crystalline structure and particle size of Ag NPs. The Surface Plasmon Resonance band was measured and observed by UV–Visible spectral studies. The defects such as Ag vacancies and interstitials were calculated by dislocation density. The FE-SEM and TEM images display the shape of particle size. The HR-TEM image shows Surface morphology, high crystallinity with lattice fringes and size of the particles. The element (presence of Ag crystal) analyzed by Energy Dispersive X-ray Spectroscopy (EDX). B. cristata leaf extract mediated silver nanoparticles, which possess very good antimicrobial activity against both E. coli and S. aureus which was confirmed by disc diffusion method. [ABSTRACT FROM AUTHOR]

This paper reports the colorimetric sensing of Fe 3+ ions in water using magnesium oxide (MgO) nanoparticles where a novel and green method to synthesize MgO nanoparticles (NPs) using Syzygium aromaticum extract (clove extract) as reducing agent has been described. The synthesized MgO NPs were characterised by various techniques i.e. UV–Vis, Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), and Energy dispersive X-ray analysis (EDX). The MgO NPs were used as colorimetric probe for the sensitive and selective sensing of Fe 3+ ions in water using UV–Vis spectrophotometry. Sensing efficiency of MgO NPs towards Fe 3+ was investigated at pH range of 3–10. The best selectivity and sensitivity was obtained at pH 3. Limit of detection was calculated using 3σ method and it was found to be 23 µM. Further, application of MgO NPs in practical sensing of Fe 3+ in real water samples was also successfully investigated. [ABSTRACT FROM AUTHOR]

The synthesis of zinc sulphide nanoparticles (ZnS NPs) using a green approach was explored. The resulting nanoparticles (NPs) were characterised by UV–vis spectroscopy, scanning and transmission electron microscopy, X‐ray diffraction and Fourier transform infrared spectroscopy. The leishmanicidal, cytotoxic and antioxidant activity of the resulting synthesised ZnS NPs (<70 nm) were evaluated against Leishmania major (L. major) promastigotes and amastigotes by MTT assay and using a macrophage model. The ZnS NPs were able to counteract the effects of oxidative metabolites as demonstrated by the oxidant activity. The IC50 value of butylated hydroxyanisole was 26.04 µg/ml as compared with the IC50 for ZnS NPs (90.95 µg/ml). The NPs displayed no cytotoxicity for the murine macrophaghes as the selectivity index (SI) fell into the safety range (SI ≥ 10). These nanomaterials exhibited good antileishmanial activity against the L. major stages that were comparable to that of Glucantime, the drug of choice. The IC50 values of ZnS NPs and Glucantime against amastigotes were 11.59 ± 2.51 and 4.95 ± 2.51 μg/ml, respectively. The IC50 values for ZnS NPs and Glucantime versus promastigote were 29.81 ± 3.15 and 14.75 ± 4.05 μg/ml, respectively. Further investigation is essential to explore the biological effects of ZnS NPs on animal and/or clinical models. [ABSTRACT FROM AUTHOR]

The present investigation reports a comprehensible and responsive strategy for identifying atrazine in several conditions using an extensive electrochemical method. CdS Quantum dots were synthesized via a greener approach, and their formation was endorsed by numerous characterization techniques such as FTIR, SEM, Raman, UV–Vis, and XRD. Owing to the splendid electrocatalytic behavior, Green CdS quantum dots (QDs) of crystallite size ∼2 nm was opted as the sensor material and were, therefore, incorporated on the bare carbon paste electrode's surface. The developed sensor demonstrated an impressive outcome for atrazine sensing accompanied by superior selectivity and sensitivity. The lower detection limit (LLOD) of 0.53 μM was attained using the developed sensor in a linear concentration range of 10–100 μM. Furthermore, the practical pertinence of the developed sensor was examined on distilled water, wastewater, and fresh liquid milk, resulting in a tremendous retrieval of atrazine (91.33–99.8%). [Display omitted] • A green novel CdS QDs sensor was fabricated using atrazine degrading bacteria. • A facile electrochemical sensor based on CdS QDs was successfully prepared. • Excellent stability and a remarkable level of selectivity towards atrazine. • The nano-sensing platform can be used to detect atrazine in real-time studies. [ABSTRACT FROM AUTHOR]

• Quinolone is an important molecule for drug design and development. • Green synthesis of 4-quinolone derivatives are highlighted (past 15 years). • Biological properties, SAR and molecular docking of 4-quinolone derivatives have been discussed. The chemistry of quinolones, representing one of the major classes of nitrogen-containing heterocyclics, has received more attention and considered one of the promising heterocyclics by organic and medicinal chemists. Globally, consistent efforts are being made by the scientific community to shift towards green chemistry at each phase of drug development thus making the processes more sustainable. In this respect, this review summarizes the results of the splendid array of eco-friendly procedures of synthesis of quinolone derivatives and their biological activities employed in the last 15 years. An effort has been made to uncover biological properties and their correlation with structure-activity relationships and molecular docking, which provide deeper insights into rational drug development. [Display omitted] [ABSTRACT FROM AUTHOR]

Perezone, a sesquiterpene quinone, is a very important molecule due to its pharmacological activities in addition to the fact that it is considered to be the first secondary metabolite isolated in the new world (America−Mexico, 1852). This study aims to offer a green comparative study about the extraction of the target molecule from the roots of the vegetable specimen Acourtia platyphilla (A. Grey). The study was performed comparing five different modes of extraction: supercritical CO2, electromagnetic infrared and microwave irradiations, mechanical-wave ultrasound versus typical mantle heating procedure. An exhaustive comparative-discussion of the obtained results is provided. It is worth noting that the corresponding quantifications were established using 1H NMR, correlating appropriately the integrals of the vinylic proton H-6 of perezone with the aromatic singlet of p-dinitrobenzene employed as an internal reference. It is also important to highlight that the four presented procedures are novel modes to extract perezone. Finally, a complementary study about the solubility of the target sesquiterpene quinone related to the use of supercritical CO2 is also reported.

In this study, the authors synthesised gold nanoparticles (Au NPs) by a green approach using an aqueous extract of empty cotton boll peels (ECBPs) which was rapid, simple and inexpensive eco‐friendly method compared to chemical and physical methods. The ECBP aqueous extract played a vital role in the reduction of Au+3 ions into Au NPs which was further confirmed by analytical characterisation. The phase purity and crystallinity of Au NPs were confirmed by X‐ray diffraction analysis. The characteristic functional groups of synthesised Au NPs were identified by Fourier transform infrared analysis. The surface morphology and topography of Au NPs were studied by scanning electron microscopy and transmission electron microscopy analysis. Size with dispersion stability of Au NPs was determined by dynamic light scattering and zeta potential studies. In this study, the authors performed a catalytic activity of Au NPs using different pollutant organic dyes such as methylene blue and methyl orange. It also showed good antioxidant activity compared to standard ascorbic acid by using the standard 1,1‐diphenyl‐2‐picryl‐hydrazil method. Hence, this study concluded that ECBP mediated Au NPs could act as a promising material for degradation of dyes and antioxidant activity. [ABSTRACT FROM AUTHOR]

In this article, biodegradable tragacanth gum (TG) biopolymer based silver nanocomposite hydrogels (SNCHs) were prepared with acrylamide as monomer using a simple redox polymerization method. TG acts as stabilizer to produce uniform and large silver nanoparticles (Ag-NPs) in presence of Terminalia chebula (TC) leaf extract in the hydrogel network. Forier transform infrared spectroscopy demonstrated the structural units of functional groups of polymeric backbone of the hydrogels. The formation of Ag-NPs in TG based hydrogels was confirmed by UV–Vis spectra. The morphology of homogeneously dispersed Ag-NPs throughout hydrogel networks was confirmed by scanning electron microscopy. TEM analysis indicates that Ag-NPs with average diameters of around 5 nm formed within the hydrogel networks. The evaluation of antibacterial activity of Ag-NPs performed against gram-negative Escherichia coli and gram-positive Bacillus subtilis bacteria and obtained results proved that these newly developed hydrogels have great potential for use in wound healing as well as water purification applications. [ABSTRACT FROM AUTHOR]

Nano conducting polymers (CPs) dispersed coatings have emerged as leading coating system, which have proved to be an effective alternative to the cariconegenic chromate coatings. Cps have emerged as non-toxic anti corrosive pigments also known as “green primers/fillers”. Here, we report microwave synthesis (MW) of conducting Poly( o -phenyldiamine) (PDA), following seven principles of “green chemistry” approach. This includes less hazardous chemical synthesis, atom economy, prevention, safer solvents, design as energy efficient process, reduction of side products and remarkably, eco-friendly nature. The use of aqueous medium during synthesis process proved to be green, renewable and free from harmful VOCs. We have also analyzed the effect of MW irradiation on various properties of Poly( o -phenyldiamine)(mPDA) and its comparison with conventionally polymerised PDA(cPDA). The FT-IR, TEM, SEM-EDX, and four probe conductivity measurements were performed to analyze and account the influence of MW irradiation on the morphology, size, solubility and electrical properties. The mPDA dispersed epoxy-polyamide (mPDA-epoxy) formulated coatings, showed superior coating properties than cPDA-epoxy nanocomposite coatings. The salt spray test and potentiodynamic polarization (PDP) studies were also conducted in pH = 9, 11 and 14, revealed that mPDA-epoxy coatings exhibited excellent corrosion resistance as compared to cPDA-epoxy. The superior physico-mechanical properties and corrosion protection performance of mPDA-epoxy confirmed our speculation of using MW for the synthesis of CPs and their use in varying applications. [ABSTRACT FROM AUTHOR]

The combination of Ciprofloxacin (CIP), a fluoroquinolone antibiotic and Tinidazole (TNZ), an anti protozoal agent has the advantage of being effective against both bacteria & protozoa and hence preferred in diarrhea and other microbial infections. A UV first order derivative spectroscopic method was developed for simultaneous estimation of CIP and TNZ in bulk and tablet dosage forms. The various analytical parameters such as linearity, precision, accuracy, limit of detection and limit of quantification were determined according to the International conference harmonization (ICH) Q2B guidelines. The present work was carried out on Shimadzu UV-1800 UV-Visible Spectrophotometer with UV probe software. 0.1N urea is used as solvent throughout the analysis and thereby developing an eco-friendly and economical method. Simultaneous estimation of CIP and TNZ by First order UV derivative spectrophotometry was carried out at zero-crossing wavelengths (ZCP), the wavelengths being 264.00 nm for CIP (ZCP for TNZ) and 295.60 nm for TNZ (ZCP for CIP). The first derivative amplitude-concentration plots were linear over the range of 0.5-8 μg/mL and 1-25 μg/mL with detection limits of 0.154 μg/mL and 0.327 μg/mL and quantification limits of 0.46 μg/mL and 0.99 μg/mL for CIP and TNZ respectively. The proposed method can be employed for the quality control of said drugs in their pharmaceutical dosage forms. [ABSTRACT FROM AUTHOR]

The properties of Polyindole (Pind) such as high redox activity, thermal stability, and slow degradation favor its use in various applications such as supercapacitors and sensors. However, due to strict current regulations, ideal materials for such applications are required to be “green” (environment-friendly), and also possess green fabrication routes. Further still, for the best performance, such materials should have electroactive morphologies fit for ions mobility-especially for energy storage. In this letter, we address the dual by presenting a simple green approach to fabricate Pind composite nanofibers via electrospinning. The resultant materials show properties fitting for use in supercapacitors and sensors. [ABSTRACT FROM AUTHOR]

Context:Marrubium vulgareLinn (Lamiaceae) was generally extracted by conventional methods with low yield of marrubiin; these processes were not considered environment friendly. Objective:This study extracts the whole plant ofM. vulgareby microwave assisted extraction (MAE) and optimizes the effect of various extraction parameters on the marrubiin yield by using Central Composite Design (CCD). Materials and methods:The selected medicinal plant was extracted using ethanol: water (1:1) as solvent by MAE. The plant material was also extracted using a Soxhlet and the various extracts were analyzed by HPTLC to quantify the marrubiin concentration. Results:The optimized conditions for the microwave-assisted extraction of selected medicinal plant was microwave power of 539 W, irradiation time of 373 s and solvent to drug ratio, 32 mL per g of the drug. The marrubiin concentration in MAE almost doubled relative to the traditional method (0.69 ± 0.08 to 1.35 ± 0.04%). The IC50for DPPH was reduced to 66.28 ± 0.6 μg/mL as compared to conventional extract (84.14 ± 0.7 μg/mL). The scanning electron micrographs of the treated and untreated drug samples further support the results. Discussion and conclusion:The CCD can be successfully applied to optimize the extraction parameters (MAE) forM. vulgare. Moreover, in terms of environmental impact, the MAE technique could be assumed as a ‘Green approach’ because the MAE approach for extraction of plant released only 92.3 g of CO2as compared to 3207.6 g CO2using the Soxhlet method of extraction. [ABSTRACT FROM PUBLISHER]

The present study demonstrates utilization of functionalized seaweed polysaccharide, namely agarose- gallate (Ag-GAEst) for the preparation of reduced graphene oxide (rGO) under mild reaction conditions. Ag-GAEst obtained with the lowest degree of substitution (degree of substitution (DS) = 0.45; with 1 : 0.5 w/w agarose : gallic acid) shows excellent performance compared to its high DS (1.1; with 1 : 2.0 w/w agarose : gallic acid) ester derivatives. Further, the formation of rGO was confirmed using UV-Vis, TEM, FTIR, Raman spectroscopy, elemental and XRD analysis. This study describes a new application of seaweedderived polysaccharides. [ABSTRACT FROM AUTHOR]

This paper describes a facile and green strategy for the synthesis of yttrium oxide nanoparticles (YO NPs) by a straightforward process using Liriope platyphylla rhizome extract as the reducing agent and yttrium nitrate hexahydrate as the sole precursor without other additives. The crystallinity, surface chemistry, morphology, elemental composition, and thermal properties of the synthesized NPs are thoroughly investigated. The synthesized NPs shows remarkable catalytic activity for the construction of biologically interesting 1,3-thiazolidin-4-ones. Graphical Abstract: [ABSTRACT FROM AUTHOR]

In this article, we report the synthesis of one-dimensional cadmium sulphide nanowires (CdS NWs) by chemical synthesis approach. These as-synthesized materials were characterized by ultraviolet-visible spectroscopy, X-ray diffraction, scanning electron microscopy with energy dispersive spectroscopy, and transmission electron microscopy analysis. These nanowires have an average diameter of ~20 nm and length up to several micrometres. CdS NWs are highly stability and are found to be a very efficient recyclable/reusable (minimum four times without any significant loss) photocatalyst for polyhydroquinoline synthesis under visible light (Halogen lamp, 70 W) at room temperature. This system offers a mild, efficient, and highly economical alternative to the existing protocols in its catalytic activity under visible light irradiation ( λ ≥ 420 nm). These findings will open up new opportunities for developing low-cost efficient photocatalyst synthesis of value added intermediates. Graphical abstract: [ABSTRACT FROM AUTHOR]

The main objective of this article was to assess the significance of factors that determine pro-environmental orientation in airport management. A survey conducted among Polish airports showed that the assessment of the factor's significance depended not only on air traffic volume but also on the degree of airports' commitment to green practices. For airports with a high level of commitment, the most important barrier was the cost. In the case of airports with a medium level of commitment, the most significant barriers were unawareness of the potential benefits, and a low priority assigned to green practices in the airport's strategic goals. For airports with a low degree of commitment, in addition to the costs, the most important barrier was the conviction that their impact on the environment was low. The most important stimulants were the same for airports with medium and high levels of pro-environmental commitment: good financial condition, pro-environmental orientation of airport authorities, and political pressure. For the airports with a low degree of commitment, growth rates of passenger traffic were the most important stimulant. All the analyzed Polish airports saw benefits primarily in the possibility of identifying, monitoring, and reducing their negative impacts on the environment (meeting the legal and political requirements), and increasing the environmental awareness of the airport authorities and employees. In terms of managerial implications, our research has demonstrated that there is a strong need to provide expert assistance to airport authorities in the field of environmental management. The objectives of European Union policy are among the most ambitious and rigorous in the world. European airports committed to net zero carbon emissions under their control by 2050 or even earlier, and a few of them have already achieved Net Zero. Nevertheless, Polish airports undertake pro-environmental measures to a very limited extent, despite the dynamic high growth of passenger traffic, and despite being subjected to the pressure of the same European policy. In this context, support from the EU policy and domestic policy is of key importance. • Polish airports undertake environmental management tools to a very limited extent. • Costs, lack of knowledge, and low environmental awareness are the main barriers. • Meeting legal and political requirements are the main stimulants. • Improving management and increasing environmental awareness are the main benefits. • Assessment of factors depends on traffic volume and the airport's involvement in green activities. [ABSTRACT FROM AUTHOR]

Copper sulfide and Fe, Ag doped copper sulfide nanopowders were synthesized by integrated hydrothermal-green approach, using Urtica dioica leaf extract as a solvent. With Fe and Ag doping, covellite as the major phase was sustained but reduction in crystallite size and change in morphology was observed. Decrease in electrical conductivity from ∼186.24 Scm−1 for undoped copper sulfide to ∼34.97 Scm−1 and ∼23.26 Scm−1 on doping Fe and Ag, respectively, at 300 K, was witnessed due to formation of different phases of copper sulfide and incorporation/segregation of Ag/Fe into copper sulfide lattice. Conversely, Seebeck coefficient showed enhanced values on doping Fe and Ag. The maximum power factor of ∼22.22 μW/mK2 was found for undoped copper sulfide. Thus, the incorporation/segregation of Fe/Ag ions in copper sulfide lattice and grain boundaries was found to alter the thermoelectric performance of copper sulfide. • Feasibility of Urtica dioica leaf extract as a solvent in hydrothermal process to synthesize copper sulfide nanoparticles. • Formation of covellite (as major phase) of copper sulfide by the hydrothermal and green integrated method. • Doping of Ag/Fe into copper sulfide lattice during the synthesis in single step. • Large decline in electrical conductivity of copper sulfide Fe and Ag doping, whereas improvement in Seebeck coefficient. • A comparative evaluation of thermoelectric parameters with reported literature on copper sulfide. [ABSTRACT FROM AUTHOR]

A novel green and efficient one-pot multicomponent reaction of dihydropyridine derivatives was reported as having good to excellent yield. In the presence of the catalyst ceric ammonium nitrate (CAN), different 1,3-diones and same starting materials as 5-bromothiophene-2-carboxaldehyde and ammonium acetate were used at room temperature under solvent-free condition for the Hantzsch pyridine synthesis within a short period of time. All compounds were evaluated for their in vitro antibacterial and antifungal activity and, interestingly, we found that 5(b–f) show excellent activity compared with Ampicillin, whereas only the 5e compound shows excellent antifungal activity against Candida albicans compared with griseofulvin. The cytotoxicity of all compounds has been assessed against breast tumour cell lines (BT-549), but no activity was found. The X-ray structure of one such compound, 5a, viewed as a colourless block crystal, corresponded accurately to a primitive monoclinic cell.

In this paper, the concept ‘green approaches’ already used in aviation is applied to cargo transportation at sea. Instead of anchoring outside a port waiting for berth, ships can adjust their speed to arrive just in time for berthing. With improved incentives for reducing speed and shared information about berthing times, green approaches instead of anchoring can be a way to reduce fuel consumption and emissions without increasing the transit times of goods. The present study estimates the benefits to society as a whole for the EU ports in the Baltic Sea with Automatic Identification System data applying a new method using data collected in real time. Data consists of all anchored ships awaiting berth on 40 different occasions in 2015 and are subsequently extrapolated to a year. Fuel consumption by the individual ships, emissions and values are calculated from the detailed data with established models and estimates of unit values. The potential benefits are estimated at 27 million euros per year in the scenario where the near 15,000 anchorings by ships annually awaiting berth may instead start a green approach 12 h prior to arrival and may reduce speed by 25%, using the middle unit values for fuel and emissions. The methodology used in the paper can be applied to estimate the benefits of green approaches in other areas with anchored vessels. [ABSTRACT FROM AUTHOR]

We report the a green approach for the synthesis of silver nanoparticles (Ag NPs) decorated magnetic graphene oxide nanocomposites (Ag@MGO NCs), which showed highly effective inhibitory property and reusability even at the very low concentration (12.5 ppm) towards Staphylococcus aureus (Gram +), Escherichia coli (Gram-) bacteria and Candida albicans fungus. It is worthy to mention that each component, such as GO, triethylene glycol (TREG) and Matricaria chamomilla ( M. chamomile ) plant extract (20% w/v), used for the synthesis of Ag@MGO NCs is safe and biocompatible. Although GO showed no significant inhibitory property, M. chamomile directed Ag@MGO NCs exhibited highly enhanced superior inhibitory activity. Benefiting from magnetic property of Ag@MGO NCs allows us for repeated use of them in inhibitory experiment. [ABSTRACT FROM AUTHOR]

There is profound interest in synthesis of nanoparticles having exceptional control over the shape and mean size distribution which is prime goal of the nanotechnology. In this research, an eco-friendly approach has been adopted to synthesize silver nanoparticles of mean size 24-33 nm using root bark extract of Berberis lycium Royle. These silver nanoparticles were characterized by UV-Visible spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and atomic absorption spectroscopy. This experimental investigation has been carried out systemically to perceive the influences of concentrations of bark extract and AgNO, temperature and pH on the morphology and mean size distribution of the evolved nanoparticles. The reduction mechanism of silver ions which lead to formation of nanoparticles has been studied and realized that alkaloids, flavonoids and sugars are predominantly involved in the growth process. This green approach has been anticipated to be facile and cost-effective for having better morphologically and mean size distribution control of silver nanoparticles and can transform the future of nano science and technology. [ABSTRACT FROM AUTHOR]

In this work, we have successfully synthesized highly biocompatible and functionalized Dioscorea alata ( D. alata ) mediated silver nanoparticles with different quantities of its extract for the evaluation of proficient bactericidal activity and optical limiting behavior. The crystalline nature of the synthesized silver nanoparticles was confirmed by powder X-ray powder diffraction (XRD) analysis and furthermore confirmed from SAED pattern of HRTEM Analysis. The Surface Plasmon Resonance band was measured and monitored by UV–Visible spectral studies. The functional groups present in the extract for the reduction and stabilization of the nanoparticles were analyzed by Fourier transform infrared spectroscopy (FTIR) technique. Surface morphology and size of particles were determined by high-resolution transmission electron microscopy analysis (HRTEM). The elemental analysis was made by Energy Dispersive X-ray Spectroscopy (EDX). The synthesized silver nanoparticles (AgNPs) in colloidal form were found to exhibit third order optical nonlinearity as studied by closed aperture Z -scan technique and open aperture technique using 532 nm Nd:YAG (SHG) CW laser beam (COHERENT—Compass 215 M-50 diode-pumped) output as source. The negative nonlinearity observed was well utilized for the study of optical limiting behavior of the silver nanoparticles. D. alata mediated silver nanoparticles possess very good antimicrobial activity which was confirmed by agar well diffusion assay method. [ABSTRACT FROM AUTHOR]

A green method for the solvothermal synthesis of copper sulphide nanoparticles (CuS NPs) using xanthan gum as a capping agent was developed. The CuS NPs were characterised by scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffraction, Brunauer–Emment–Teller, zeta analysis, thermal gravimetric– differential thermal analysis, Fourier transform infrared and UV–visible absorption spectra. These characterisations together determine the composition, structural, thermal and optical properties. The UV–visible spectrum had a broad absorption in the visible range. The particle size of the products was observed by TEM in the range of 8–20 nm. The photocatalytic performance of the CuS NPs was evaluated for the degradation of organic dyes (methylene blue, rhodamine B, eosin Y and congo red) under irradiation of solar, visible and UV lights. The CuS NPs showed good photocatalytic activity. Kinetic analyses indicate that the photodegradation rates of dyes usually follow pseudo-first-order kinetics for degradation mechanisms. [ABSTRACT FROM AUTHOR]

Due to industrial effluent (textile, paper, leather, etc.), dye is unfavorably prevalent in water bodies. This is a major source of contamination that must be eliminated since it poses a substantial harm to the ecology. Tinospora cordifolia (T. cordifolia) stem extract has the potential to be used in the ecologically sound and non-toxic biosynthesis of zinc oxide nanoparticles for biomedical applications and wastewater remediation. These NPs have a hexagonal phase with a wurtzite structure, according to X-ray diffraction (XRD) experiments. At 3.55, 3.56, and 3.67 eV, the optical band gap was shown to exist. Images taken using a scanning electron microscope (SEM) show that there are flower-shaped and agglomerated nanoparticles. Under UV light, the photocatalytic effectiveness of biosynthesized ZnO NPs was evaluated for the methylene blue (MB) dye degradation process. Following a first order kinetic model, 99% of the dye was broken down in 180 min. The created ZnO NPs can therefore be employed as photocatalysts for the breakdown of dye in wastewater. Additionally, the green approach's stabilised NPs from the stem of the (T. cordifolia) plant may be effective against the bacterial strains Staphylococcus aureus and Escherichia coli. The lowest observed MIC and MBC values for S. aureus and E. coli were 10.45 μg/mL, 93.57 μg/mL and 20.24 μg/mL, 121.02 μg/mL respectively. Additionally, ZnO NPs have demonstrated outstanding antifungal efficacy. When the fungicidal % inhibition was evaluated on the R. nectrarix and F. oxysporum clinical strains, inhibition zones of 51 mm by 1.00 mm and 34 mm by 0.57 mm, respectively, were found. • ZnO NPs synthesized using extract of Tinospora cordifolia leaf. • Investigation involving precipitation method to synthesize phytomediated ZnO NPs. • 99% of the dye was broken down in 180 min. • Photocatalytical results followed first order kinetic model. [ABSTRACT FROM AUTHOR]

[Display omitted] • Application of SCF technology is reviewed for the resource recovery from waste. • Various SCF solvents are discussed thoroughly to recycle e-waste and plastic waste. • Economic analysis of SCF technology is studied and compared with other technologies. • Recommended to perform pilot scale studies to comprehend the industrial application. • Circular economy for resource recovery from waste is explored. Rapid technological development and modernization lead to increased production and consumption of electronic equipment as well as plastic commodities. This results in a large generation of electronic waste (e-waste) and plastic waste. The most severe problem associated with these wastes is their informal recycling and improper disposal, threatening the environment and human health. On the other hand, these wastes also provide an opportunity for the recovery of metals and the generation of valuable products. Supercritical fluid technology provides an attractive alternative for the sustainable management of e-waste and plastic waste, as well as resource recovery from these wastes. Therefore, the present review focuses on the applications and potential of supercritical fluid technology for resource recovery from these wastes. The review article presents a comprehensive discussion about the generation and composition of e-waste and plastic waste, the principle of supercritical fluid technology, and the application of various supercritical solvents such as CO 2 , water, and alcohol for resource recovery from e-waste and plastic waste. Finally, the economic aspect of supercritical fluid technology is also critically reviewed, and a comparative economic analysis with existing technologies is presented. Based on critical analysis, it is observed that supercritical fluid technology provides a viable route for the treatment of both e-waste and plastic waste. However, the pilot-scale studies are not reported, and there is a need to further explore the supercritical fluid technology to make a strong case for industrial application. [ABSTRACT FROM AUTHOR]

Graphene/zinc oxide nanocomposite was synthesised via a facile, green and efficient approach consisted of novel liquid phase exfoliation and solvothermal growth for sensing application. Highly pristine graphene was synthesised through mild sonication treatment of graphite in a mixture of ethanol and water at an optimum ratio. The X-ray diffractometry (XRD) affirmed the hydrothermal growth of pure zinc oxide nanoparticles from zinc nitrate hexahydrate precursor. The as-prepared graphene/zinc oxide (G/ZnO) nanocomposite was characterised comprehensively to evaluate its morphology, crystallinity, composition and purity. All results clearly indicate that zinc oxide particles were homogenously distributed on graphene sheets, without any severe aggregation. The electrochemical performance of graphene/zinc oxide nanocomposite-modified screen-printed carbon electrode (SPCE) was evaluated using cyclic voltammetry (CV) and amperometry analysis. The resulting electrode exhibited excellent electrocatalytic activity towards the reduction of hydrogen peroxide (H 2 O 2 ) in a linear range of 1–15 mM with a correlation coefficient of 0.9977. The sensitivity of the graphene/zinc oxide nanocomposite-modified hydrogen peroxide sensor was 3.2580 μAmM −1 with a limit of detection of 7.4357 μM. An electrochemical DNA sensor platform was then fabricated for the detection of Avian Influenza H5 gene based on graphene/zinc oxide nanocomposite. The results obtained from amperometry study indicate that the graphene/zinc oxide nanocomposite-enhanced electrochemical DNA biosensor is significantly more sensitive ( P < 0.05) and efficient than the conventional agarose gel electrophoresis. [ABSTRACT FROM AUTHOR]

In this work, an environmental friendly RC/N-TiO 2 nanocomposite thin film was designed as a green portable photocatalyst by utilizing recycled newspaper as sustainable cellulose resource. Investigations on the influence of N-doped TiO 2 nanorods incorporation on the structural and morphological properties of RC/N-TiO 2 nanocomposite thin film are presented. The resulting nanocomposite thin film was characterized by FESEM, AFM, FTIR, UV–vis–NIR spectroscopy, and XPS analysis. The results suggested that there was a remarkable compatibility between cellulose and N-doped TiO 2 nanorods anchored onto the surface of the RC/N-TiO 2 nanocomposite thin film. Under UV and visible irradiation, the RC/N-TiO 2 nanocomposite thin film showed remarkable photocatalytic activity for the degradation of methylene blue solution with degradation percentage of 96% and 78.8%, respectively. It is crucial to note that the resulting portable photocatalyst produced via an environmental and green technique in its fabrication process has good potential in the field of water and wastewater treatment application. [ABSTRACT FROM AUTHOR]

In this communication, a greener methodology for the systematic tuning of spherically shaped gold nanoparticles is presented. Bioconjugated l -cysteine is used as a capping/reducing agent for the synthesis. The prepared nanoparticles are characterized by XRD, FTIR, UV-absorption, SEM and HRTEM measurements to study their properties. The five different sizes of gold nanoparticles ranging from 3.9 nm to 5.6 nm are successfully synthesized. The results of optical absorption show a shift in plasmon peak with the increase in particle size and FTIR measurements confirm a strong binding of l -cysteine molecules on gold surface. The effect of l -cysteine concentration is studied and these results reveal the formation of a new metal-organic complex. This material shows solvent dependent visible fluorescence and the fluorescent intensity follows an ordered sequence with dipole moment of the solvents used. Metal to ligand charge transfer is found the reason for this behavior. The present gold nanoparticles may find potential applications in various fields of biological/chemical sciences as biologically conjugated materials. [ABSTRACT FROM AUTHOR]

A sensitive electrochemical sensor based on in situ modification of graphite electrode via graphene nanosheets (GNs) was developed as a green method for prazosin hydrochloride (PRA) analyses. In this study, GNs were electrochemically synthesized on the surface of graphite electrode via in situ approach and used for the analyses. The proposed sensor showed several advantages such as high sensitivity, low LOD, and excellent repeatability. The oxidation peak current at the optimum analytical conditions using a GNs/graphite electrode at pH 6.0 was linearly dependent on PRA concentration in the range of 0.09-100 µM. A LOD of 0.02 µM and RSD of 3.8 % for 10 µM solution of PRA with a great recovery were obtained. [ABSTRACT FROM AUTHOR]

The carbon footprint is widely recognized as an indicator of greenhouse gas emissions. Carbon footprint modeling based on life cycle assessment is applied to assess the average contribution of greenhouse gases to the atmosphere of the orchard system during the growing season. Apple fruits are exposed to various conditions in the supply chain, causing mechanical damage, scars, and bruises, ultimately reducing product quality and shelf life. Research has been conducted over the years to identify the proper packaging method to minimize shipping losses and minimize emissions while on transportation from production sites to distant markets and during storage. The objective of this paper is to maximize the profit of apple orchards with effective control over emissions and deterioration. Therefore, the data was statistically analyzed by using Mathematica 9.0 software and a graphical solution is obtained. A real-life case study at an apple orchard in Jammu and Kashmir will be used to validate a mathematical model with theoretical and computational procedures. This model is highly desirable and effective and is acceptable to businesses, traders, and consumers because it minimizes the losses through small scratches, better retention of appearance, crispness, flavor, and long shelf life with a high net profit, high cost of performance, and affordability for consumers. The key findings were recorded using sensitivity analysis and its application in apple orchards is elucidated through managerial insights. The circular economy approach in this study that combines green and conservation investments provides a path to a more sustainable environment as well as lower emissions and lower degradation rates. [Display omitted] • A sustainable integrated circular economy system for an apple orchard is studied. • Two-layered supply chain comprising of manufacturer and retailer is taken. • Optimal value for green and preservation technology investment and circular index is studied. • Various non-linear relationships of profit and circular demand functions analyzed under the carbon cap and trade policy are considered. • Emission control technologies and deterioration control along with a circularity index for an item made a good impact on profit. [ABSTRACT FROM AUTHOR]

Carbon capture technologies have advanced in recent years to meet the ever-increasing quest to minimize excessive anthropogenic CO 2 emissions. The most promising option for CO 2 control has been identified as carbon capture and storage. Among the numerous sorbents, char generated from biomass thermal conversion has shown to be an efficient CO 2 adsorbent. This study examines various characteristics that can be used to increase the yield of biochar suited for carbon sequestration. This review gives recent research progress in the area, stressing the variations and consequences of various preparation processes on textural features such as surface area, pore size and sorption performance with respect to CO 2 's sorption capacity. The adjoining gaps discovered in this field have also been highlighted herewith, which will serve as future work possibility. It aims to analyse and describe the possibilities and potential of employing pristine and modified biochar as a medium of CO 2 capture. It also examines the parameters that influence biochar's CO 2 adsorption ability and pertinent challenges regarding the production of biochar-based CO 2 sorbent materials. • Carbon capture and storage are the most promising option for CO 2 control. • Char generated from biomass thermal conversion shown to be an efficient CO 2 adsorbent. • This study analyzes CO 2 capture possibilities of using unmodified and modified biochar. • Biochar plays a very significant role in sustainable CO 2 sorption. • Overall process efficacy is compromised without regeneration and reuse of biochar. [ABSTRACT FROM AUTHOR]

A general, simple, efficient, cost-effective and environmental benign procedure for the syntheses of 4-aryl-3,4-dihydropyrimidin-2(1H)-ones (DHPMs) has been developed. The reaction is efficiently catalysed by using various amino acids viz., glycine, L-proline, L-cysteine, leucine and tryptophan. Reactions give excellent yields under reflux conditions. The chemical structures of these compounds were identified by Fourier Transform-Infra Red Spectroscopy (FT-IR), Gas Chromatography-Mass Spectroscopy (GC-MS) and Nuclear Magnetic Resonance Spectroscopy (1H NMR). Physical parameters such as m.p., mixed m.p. as well as TLC also helped to characterize the expected products. The progress of the reaction time and purity was checked by TLC and the products were purified by recrystallization using ethyl acetate as a solvent. The synthesized molecule has numerous biological applications as it is anti-microbial, anti-inflammatory and anti-hypertensive in character.