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In this work, waste C. grandis peel was the ingredient used to extract essential oil and naringin by a supercritical CO2 technique. Both natural products were evaluated for antimicrobial activity and docking studies.

κ-Oligocarrgeenan (OC) is well known as an effective and green plant growth promoter and elicitor. However, its effect on coffee plant has not been investigated so far. This study aimed to examine the impacts of OC on biophysical activity, vegetative growth and productivity of coffee plant (Coffea robusta). OC with average molecular weight (AMW) of 4.0 kDa was prepared by depolymerization of carrageenan using ascorbic acid. Field experiments were conducted by foliar spray four times per year at various OC concentrations (50, 100, 150, 200, and 250 ppm) for three years (2017-2019). The results showed that OC promoted growth of coffee plant in all tested concentrations, and an optimized concentration was found at 150 ppm which showed a significant increase compared to the control plant in total chlorophyll (24.79%), carotenoid (31.65%), uptakes of N (15.66%), P (15.81%), and K (22.25%) minerals in leaves, crop yield (19.80%) and bean size (13.10%). Therefore, OC is potentially promising to apply as a promoter to enhance yield of crops for sustainable coffee plantation.

Efforts to improve the solar power conversion efficiencies of binary bulk heterojunction-type organic photovoltaic devices using an active layer consisting of a poly-(3-alkylthiophene) (P3AT) homopolymer and a suitable fullerene derivative face barriers caused by the intrinsic properties of homopolymers. To overcome such barriers, researchers might be able to chemically tailor homopolymers by means of monomer ratio-balanced block copolymerization to obtain preferable properties. Triblock copolymers consisting of three components—3-hexylthiophene (HT), 3-butylthiophene (BT), and 3-octylthiophene (OT)—were synthesized via Grignard metathesis (GRIM) polymerization. The component ratios of the synthesized block copolymers were virtually the same as the feeding ratios of the monomers, a fact which was verified using 1H-NMR spectra. All the copolymers exhibited comparable crystalline and melting temperatures, which increased when one type of monomer became dominant. In addition, their power conversion efficiencies and photoluminescence properties were governed by the major components of the copolymers. Interestingly, the HT component-dominated block copolymer indicated the highest power conversion efficiency, comparable to that of its homopolymer, although its molecular weight was significantly shorter.

The plant extract has been used extensively for biosynthesis of noble metallic nanoparticles due to cost efficiency and simple technology. However, influence of plant growth condition can induce changes in composition and content of bioactive compounds, leading to difficulty in reproducing the metallic nanoparticles. In this work, we first utilized the plant embryos (Panax vietnamensis embryos—PVE) cultured under laboratory condition as a biosource for the synthesis of silver nanoparticles (AgNPs). This method can reduce unwanted changes of bioactive composition in the plant. The formation of AgNPs was optimized to afford the best colloidal solution. The physicochemical properties were characterized using analysis techniques including X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), Fourier transform infrared spectroscopy (FTIR) and thermal properties. Size of crystalline AgNPs was determined in the range of 3–20 nm with a mean size of 10 nm. The applications were investigated for antibacterial and catalytic effect. The biosynthesized AgNPs exhibited high antibacterial activity against Bacillus subtilis, Staphylococcus aureus and Escherichia coli. The excellent catalysis behavior of PVE-AgNPs has been investigated for the reduction of o-, m-, p-nitrophenols and toxic organic dyes including methyl orange, rhodamine 6G and rhodamine B. The effect of catalyst amount on the reaction performance was studied via kinetic investigation. This work unfolds a potential method for scalable reproduction of metallic nanoparticles.

This study proposes a photonic crystal fiber made of fused silica glass, with the core infiltrated with chloroform as a new source of supercontinuum (SC) spectrum. We numerically study the guiding properties of the fiber structure in terms of characteristic dispersion and mode area of the fundamental mode. Based on the results, we optimized the structural geometries of the CHCl3-core photonic crystal fiber to support the broadband SC generations. The fiber structure with a lattice constant of 1 μm, a filling factor of 0.8, and the diameter of the first-ring air holes equaling 0.5 μm operates in all-normal dispersion. The SC with a broadened spectral bandwidth of 0.64 to 1.80 μm is formed by using a pump pulse with a wavelength of 850 nm, 120 fs duration, and power of 0.833 kW. That fiber would be a good candidate for all-fiber SC sources as cost-effective alternative to glass core fibers.

The diastereoselectivity of adducts in the addition reaction via the Felkin-Anh model is affected significantly by the steric effect of bulky groups. However, the influence of steric alkyl chain length has not been studied for the diastereoselectivity. In this work, we present a new strategy for the racemic synthesis of β-methyl alcohols to obtain various diastereomer ratios using the Felkin-Anh model. The addition of alkyl Grignard reagents to α-methyl aldehydes afforded diastereomer ratios of threo/erythro ≈ 2:1, while the reduction in structurally related ketones using LiAlH4 afforded ratios of threo/erythro ≈ 1:1. The experimental data showed no effect of alkyl chain length on either side on the stereoselectivity of adducts. All synthesized analogues were evaluated for attractiveness to Rhynchophorus ferrugineus weevils in the field. Five novel derivatives, including two alcohols and three ketones, were found to attract weevils in the field trials. Among them, 3-methyldecan-4-one (5b) and 4-methyldecan-5-ol (11a) were found to be the most attractive to the insects.

Spherical zinc is well known as an effective pigment for the corrosion protection of carbon steel. However, a high proportion of spherical Zn in a coating leads to difficulties in fabricating the coating solution and increased cost. In this work, the influence of flake ZnAl alloy in silicate coatings on the corrosion protection properties of steel substrates was investigated. The electrochemical behaviour of coatings containing different flake ZnAl alloy content immersed in NaCl solution (3.5 wt%) was evaluated using an electrochemical impedance spectroscopy (EIS) method. A salt spray test was performed to evaluate corrosion on the coating surface. Pull-off tests of the coatings before and after the salt spray process were performed, and the surface morphology was analysed to determine the degradation of corrosion resistance. The results show that silicate coating containing flake ZnAl alloy (25 wt%) possesses the highest total resistance (1417 Ω) and the longest time to the appearance of white rust (720 h). The surface morphology of the coating containing 25 wt% flake ZnAl alloy was found to include corrosion products with the most compacted surface, which effectively prevents the penetration of electrolytes to the interface between the coating and the steel.

The extraction of bioactive compounds, including essential oils and flavonoids, using organic solvents is a significant environmental concern. In this work, waste

This study develops an effective method for the in situ synthesis of palladium nanoparticles (PdNPs) using Cyclea barbata pectin as a green reducing and stabilizing reagent. The PdNP@pectin nanocomposite was well characterized by analysis techniques such as UV-vis, FTIR, EDX, XRD, SEM, HR-TEM and STEM-mapping. Crystalline PdNPs were found to be distributed in the size range of 1–25 nm with the highest frequency of 6–12 nm. PdNP@pectin exhibited excellent recyclable catalysis activity for the Heck coupling reaction in water medium. The kinetics and recyclability of nanoparticles were investigated for the catalytic reduction of o-, m- and p-nitrophenol. The result showed a good catalysis efficiency with five successful recycles without compromising much. In particular, the nanocomposite was used as a catalyst for the conversion of alkynes into cis-alkenes with KOH/DMF as a hydrogenation source. The reaction was also utilized effectively for the synthesis of sex pheromones, including Plutella xylostella ((Z)-11-hexadecen-1-yl acetate) and Cylas formicarius ((Z)-3-dodecen-1-yl(E)-2-butenoate) with the total yields of 70% and 68%, respectively. Therefore, PdNPs supported on C. barbata pectin are promising catalysis materials for application in various fields.

The present work presented a synthesis of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) using the aqueous extract of waste banana stem (WBS), Musa paradisiaca Linn. The reduction and formation of MNPs have been characterized by several analysis techniques such as X-ray diffraction (XRD), Fourier transmission infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM). The techniques showed that average particle size of WBS-AgNPs and WBS-AuNPs in crystalline nature was in ranges of 7–13 nm and 11–14 nm, respectively. The synthesized nanoparticles were used to evaluate antibacterial activity and catalysis. The WBS-AgNPs showed strong antibacterial activity against B. subtilis and E. coli. The largest zone of inhibition against B. subtilis (14.2 mm) and E. coli (9.3 mm) was found at concentrations of 4.0 ppm and 2.0 ppm, respectively. The excellent catalytic application of both the nanoparticles for the reduction of 4-nitrophenol was confirmed via study on their kinetics. The normalized kinetic constants (knor) of WBS-AgNPs and WBS-AuNPs were found to be 1.72 × 10–3 s−1 mg−1 and 2.45 × 10–3 s−1 mg−1, respectively.

In this study, BiVO4 was successfully synthesized via the solvothermal process using a solvent mixture of ethylene glycol and water under different synthesis conditions of temperature and pH. Physicochemical properties such as crystal phase, morphology, and optical absorption of the as-synthesized BiVO4 samples were characterized by X-ray diffraction (XRD), Raman spectra, field emission scanning electron microscopy (FE-SEM), and ultraviolet–visible diffraction reflection spectroscopy (UV–vis DRS). The XRD analysis showed that different synthesis conditions of temperature and pH significantly affected the growth of monoclinic BiVO4 crystals oriented along (0 4 0) facets. Form SEM results, the synthesis conditions, including pH and temperature, have a great effect on the morphology of monoclinic structured BiVO4. As the pH value increases in the range of 0–9 and temperature increases from 80 °C to 180 °C, the morphology of BiVO4 changed from peanut-, rod-, and leaf-like shapes. The photocatalytic activities of as-synthesized BiVO4 photocatalysts were evaluated by the photodegradation of methylene blue (MB) dye under irradiation of white LED light. We have found that by using appropriate synthesis conditions (the synthesis temperature of 140 °C and the synthesis pH of 7) the BiVO4 exhibited high photocatalytic efficiency for MB degradation (about 82.30% after 180 min of irradiation). This result is due to the development of the BiVO4 crystals oriented along (0 4 0) facets with an increase in the intensity ratio of I(0 4 0)/I(1 2 1). The growth of BiVO4 crystals oriented along (0 4 0) facets may be beneficial to enhance the photocatalytic activity of monoclinic scheelite BiVO4.

Biogenic synthesis of noble metal nanoparticles is particularly interested due to the effective applications for plasmonic catalysis and bioactivity. In this work, aqueous extract of waste Nypa fruticans (NF) fruit husk was utilized to synthesize silver nanoparticles (NF-AgNPs) and gold nanoparticles (NF-AuNPs). The effected parameters on the green reduction of metallic nanoparticles (MNPs) were investigated. Under optimum conditions of concentration, temperature and time, the biosynthesized NF-AgNPs and NF-AuNPs showed spherical nanoparticles with average size of 10–15 nm and 15–20 nm, respectively. The presence of AgCl in NF-AgNPs has been demonstrated by X-ray diffraction analysis. The elemental components of all samples confirmed the presence of anions and cations come from the aqueous extract. The biosynthesized nanoparticles were evaluated bacterial activity against three bacterial strains. NF-AgNPs exhibited selective antibacterial activity against Bacillus cereus but no activity against Staphylococcus aureus and Salmonella typhimurium at all tested concentrations. The recyclable catalysis activity of the biosynthesized nanoparticles was evaluated for the reduction of nitrophenols in the presence of sodium borohydride which possessed good catalytic performance in six running numbers. Additionally, AgCl played role as a source supplying AgNPs has been demonstrated in catalytic reduction of p-nitrophenol. For study of catalytic kinetic, NF-AgNPs possessed higher rate constant in comparison with NF-AuNPs whereas TOF values of NF-AuNPs was determined to be higher than those of NF-AgNPs.

In this study, biogenic silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) were synthesized by a green approach using an aqueous extract from Codonopsis pilosula (CP) roots as a reducing and stabilizing agent. The formation of CP-AgNPs and CP-AuNPs was confirmed and optimized by UV-Vis spectroscopy. The CP-AgNPs and CP-AuNPs obtained under optimum conditions of metal ion concentration, reaction temperature, and reaction time were characterized by high-resolution transition electron microscopy (HR-TEM), selected area electron diffraction (SAED) analysis, field-emission scan electron microscopy (FE-SEM), powder X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, dispersive X-ray spectroscopy (EDX), and dynamic light scattering (DLS) method. It has been found that the biosynthesized CP-AgNPs and CP-AuNPs were formed in spherical shape with an average size of 10±2.5 nm and 20±3.2 nm, respectively. The biosynthesized metallic nanoparticles exhibited selective bacterial activity against three bacterial strains including two Gram-positive bacteria of Bacillus subtilis and Staphylococcus aureus and one Gram-negative bacteria of Escherichia coli. Meanwhile, there was no antibacterial activity detected toward Gram-negative Salmonella enteritidis. CP-AgNPs and CP-AuNPs also manifested an excellent catalytic performance in the reduction of 1,4-dinitrobenzene, 2-nitrophenol, 3-nitrophenol, and 4-nitrophenol.

This work describes a simple single-step method for green synthesis of colloidal gold nanoparticles (AuNPs) using Litsea cubeba (LC) fruit extract as a reducing as well as stabilizing agent simultaneously. Major parameters affecting the formation of LC-AuNPs, including gold ion concentration, reaction time, and reaction temperature were optimized using ultraviolet-visible (UV-Vis) measurements at a characteristic maximum absorbance of 535 nm. The functional groups responsible for reducing gold ions and capping AuNPs were examined by Fourier-transform infrared (FTIR) spectroscopy. Powder X-ray diffraction (XRD) analysis revealed the crystalline nature of AuNPs. Transmission electron microscopy (TEM) measurements showed that the biosynthesized LC-AuNPs were mostly spherical with an average size of 8-18 nm. The nanoparticles also demonstrated excellent ultrarapid catalytic activity for the complete reduction of 4-nitrophenol to p-aminophenol in the presence of NaBH4 within 10 min with a reaction rate constant of 0.348 min-1.

The design of novel molecules is imperative for the discovery of potent drugs in the medicinal chemistry field. In this work, new 1,3,5-substituted pyrazoline sulphonamides were synthesised using a two-step process with microwave assistance and evaluated biologically for their antimicrobial, antiproliferative, and anti-inflammatory properties. Most of the sulphonamides bearing 3-OH or 4-Cl groups exhibited significant inhibition of two Gram-positive bacteria, Bacillus subtillis and Staphylococcus aureus, and the yeast Candida albicans. Six compounds showed good activity against the cancer cell lines cervix carcinoma (Hep-2C) and human lung carcinoma (A549) with IC50 in the range 16.03 ± 1.63 to 22.75 ± 0.19 μM and 18.64 ± 1.02 to 20.66 ± 2.09 μM, respectively, and exhibited low toxicity against mammalian Vero cells. In evaluating in vitro anti-inflammatory behaviour, five compounds showed high inhibition of NO production over the standard reference, with low toxicity against murine macrophage cell line RAW 264.7. Further investigation found that two compounds, 1b and 18b, exhibited the highest activity when testing mouse ear oedema. The findings are promising for the discovery of potent new drugs.

A series of poly-3-alkylthiophenes (P3ATs) with butyl (P3BT), hexyl (P3HT), and octyl (P3OT) side-chains and well-defined molecular weights (MWs) were synthesized using Grignard metathesis polymerization. The MWs of P3HTs and P3OTs obtained via gel permeation chromatography agreed well with the calculated MWs ranging from approximately 10 to 70 kDa. Differential scanning calorimetry results showed that the crystalline melting temperature increased with increasing MWs and decreasing alkyl side-chain length, whereas the crystallinity of the P3ATs increased with the growth of MWs. An MW-dependent red shift was observed in the UV–Vis and photoluminiscence spectra of the P3ATs in solution, which might be a strong evidence for the extended effective conjugation occurring in polymers with longer chain lengths. The photoluminescence quantum yields of pristine films in all polymers were lower than those of the diluted solutions, whereas they were higher than those of the phenyl-C61-butyric acid methyl ester-blended films. The UV–Vis spectra of the films showed fine structures with pronounced red shifts, and the interchain interaction-induced features were weakly dependent on the MW but significantly dependent on the alkyl side-chain length. The photovoltaic device performances of the P3BT and P3HT samples significantly improved upon blending with a fullerene derivative and subsequent annealing, whereas those of P3OTs mostly degraded, particularly after annealing. The optimal power conversion efficiencies of P3BT, P3HT, and P3OT were 2.4%, 3.6%, and 1.5%, respectively, after annealing with MWs of ~11, ~39, and ~38 kDa, respectively.

The study reports a versatile, cost-efficient and ecofriendly protocol for the synthesis of biogenic silver nanoparticles (AgNPs) using the aqueous extracts of Quao Binh Chau, Stereospermum binhchauensis and Che Vang, Jasminum subtriplinerve and their application in antibacterial activity and catalysis. The AgNPs with varying morphology and physical properties have been optimized using the absorption measurements. The biogenic AgNPs have been characterized by Fourier transform infrared spectroscopy, UV–Vis spectroscopy, transmission electron microscopy, X-ray diffraction analysis, energy-dispersive X-ray spectroscopy and thermal behaviors. Stable crystalline AgNPs with average particle sizes of 20.0 nm and 8.0 nm were fabricated from aqueous extract of Quao Binh Chau and Che Vang, respectively. The phytochemicals from the extracts involved in reduction and stabilization of AgNPs are identified by FTIR spectra and thermal gravimetric analysis. Both the biosynthesized AgNPs show the potent antibacterial activity against four tested bacterial strains including Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Agrobacterium tumefaciens. High catalytic activity of the biogenic AgNPs in the degradation of toxic contaminants (4-nitrophenol and methyl orange) was observed. The antibacterial and catalytic activities are found to be size and phytochemical dependent. The antibacterial and catalytic activities of the biogenic nanoparticles would find applications in the biomedical and environmental fields.

Two series of sulfonamides were synthesized from 4-hydrazinyl­ben­zenesulfonamide as the key starting material. 1,3,5-Tri­arylpyrazoline sulfon­amides ( 2a – i ) were obtained by cyclocondensation of various chalcones in 53–64 % yields, while 4-thiazolidinone derivatives ( 4a – e ) were synthesized by cyclocondensation between mercaptoacetic acid and different phenylhydra­zones in 43–62 % yields. The synthesized compounds were characterized based on FTIR, 1H-NMR, 13C-NMR and HRMS data. The sulfonamides were evaluated for their in vitro antimicrobial activities against four bacterial strains (E. coli, P. aeruginosa, B. subtillis and S aureus), two filamentous fungal strains (A. niger and F. oxysporum) and two yeast strains (C. albicans and S. cerevisiae). Seven pyrazolines, 2a – c and 2e – h , exhibited significant inhibition of different microbial strains. Among them, compound 2b displayed good anti­fungal activity against A. niger (MIC value at 12.5 mg mL-1) over the reference drug.

Crinum latifolium (CL) leaf is a source of various biologically active compounds such as alkaloid and phenolic compounds, which exhibit anti-inflammatory, antitumor, and antimicrobial effects. In the purpose of expanding applications for the field of bionanotechnology, we report biosynthesis of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) by using aqueous extract from C. latifolium leaf and explore antibacterial activity and catalytic performance for degradation of pollutants. The formation of CL-AgNPs and CL-AuNPs is confirmed and optimized by UV-visible spectroscopy with surface plasmon resonance (SPR) peaks at around 402 and 539 nm, respectively. The spherical CL-AgNPs have an average diameter of 20.5 nm and the multishaped CL-AuNPs possess an average size of 17.6 nm. The actions of four bacterial strains were strongly inhibited by using the CL-AgNPs. Furthermore, the biosynthesized metallic nanoparticles (MNPs) exhibited the excellent catalytic degradation performance of pollutants.

In this study, ionic liquids (ILs) were first used as solvents for conversion of hesperidin into diosmin. The diosmin was successfully synthesized by using iodine oxidation in ionic liquids including [BMIM]Br, [BMIM]BF4, [BMIM]OTf, [BPY]Br, [BPY]BF4 and [BPY]OTf. The results showed the reaction achieved in good yields (57- 76%). Among them, [BPY]Br and [BPY]BF4 exhibited as excellent solvents for the oxidation of hesperidin. In particular, water content in recovered ionic liquids (ILs), which affected strongly recyclable performance in the oxidation of hesperidin, has been investigated. It found that water content in [BPY]Br from 1 % to 5% (v/v) induced a significant increase of the synthetic yield.

The present study describes an eco-friendly approach for the synthesis of colloidal solution of silver and gold nanoparticles (L-AgNPs and L-AuNPs) from the aqueous extract of Lactuca indica leaf. Major parameters affecting on the formation of L-AgNPs and L-AuNPs were optimized using UV–Vis analysis at absorption maximum around 423 nm and 531 nm, respectively. The plant extract as reducing and capping agents of MNPs was demonstrated by Fourier-transform infrared (FTIR) spectroscopy. The nanoscale of metals was confirmed by Transmission electron microscopy (TEM) measurements. TEM studies revealed that L-AgNPs were mostly spherical with average size of 13.5 nm and L-AuNPs possessed multi shapes with an average size of 14.5 nm. Selected area electron diffraction (SAED) analysis and X-ray diffractometer (XRD) data confirm their crystalline structure. The nanomaterials showed efficient catalysis in the degradation of 4-nitrophenol and methyl orange.

Multiple sharp-edged gold nanostars were efficiently assembled on nanopipette tips through electrostatic interactions for use as a potent intracellular hypoxia-sensing Raman probe. Colloidal stability and surface immobilization were checked using scanning electron microscopy, light scattering, and zeta potential measurements. Site-specific intracellular hypoxia levels can be estimated in vitro and in vivo using Raman lancets (RL). Distinct Raman spectral changes for the nitro-(NO2 ) functional group of the redox marker 4-nitrothiophenol (4NTP) can be quantified according to the intracellular oxygen (O2 ) content, ranging from 1 % to 10 %. Redox potential changes in mitochondrial respiration were also examined through serial injections of inhibitors. 3D-cultured cells and in vivo tests were used to validate our method, and its application in the assessment of the aggressiveness of cancer cells by differentiating spectral changes between malignant and benign cells was demonstrated.