003982   KUMAR L V, NATH G R (PG and Research Chemistry Dep, KSM DB Coll, Kerala- 690 521) : Synthesis, characterization and biological studies of cobalt(II), nickel(II), copper(II) and zinc(II) complexes of vanillin-4-methyl-4-phenyl-3-thiosemicarbazone. J Chem Sci 2019, 131(8), 76.

Complexes of vanillin-4-methyl-4-phenyl-3-thiosemicarbazone with cobalt(II), nickel((II), copper(II) and zinc(II) metal ions were synthesized and characterized by elemental analysis, molar conductance, magnetic moment, infrared spectra, electronic spectra, ¹H and ¹³C NMR, mass spectrum and thermal analysis. The low molar conductance values indicate that all the complexes are non-electrolytes. Spectral studies indicate that the ligand act in a tridentate manner coordinating with the metal ion through sulphur, oxygen and nitrogen atoms. Based on magnetic moment measurements, spectral studies and thermal analysis, suitable geometry was proposed for the metal complexes. Thermal stability of the complexes was ascertained on the basis of thermo gravimetric analysis and the lattice parameters, space group and grain size of the ligand and complexes were determined by using powder XRD measurements. Surface morphology of ligand and complexes were studied using SEM analysis. Antimicrobial studies were carried out against gram-positive, gram-negative bacteria and two fungal pathogens.

14 illus, 2 tables, 44 ref

003968   FEDOSOV A, FEDOSOVA M, POSTNIKOVA I, OREKHOV S, GUSHCHIN A, RYABININ D, CHUZHAIKIN I (National Research Univ, Russia- 603 950) : Synthesis and characterization of hierarchical titanium-containing silicas using different size templates. J Chem Sci 2019, 131(8), 77.

The development of hierarchical catalytic heterogeneous catalytic systems with a controlled micro/mesopore ratio is an important issue in catalysis. The main purpose of the paper is to the establish influence of the size of the template molecule on the main characteristics of hierarchical titanium-containing silicas (H-TS). The H-TS were successfully synthesized by a bi-template method using tetrapropylammonium hydroxide (TPAG) as permanent template of MFI topology and tetramethylammonium bromide (TMAB), tetraethylammonium bromide (TEAB), tetrabutylammonium hydroxide (TBAG), dodecyltrimethylammonium bromide (DTMAB), cetyltrimethylammonium bromide (CTAB), didecyldimethylammonium chloride (DDAC), tetradecylbenzyldimethylammonium bromide (TBDAB) as variable structure-directing agent (SDA) of a different size. The structure and morphology were characterized by X-ray diffraction, a Fourier transform infrared spectroscopy, a Raman spectroscopy, a scanning electron microscopy and low-temperature nitrogen adsorption-desorption. The catalytic properties of the prepared titanium-containing micro-mesoporous silicas for hydroxylation of phenol with H₂O₂ have been evaluated, and their activities have been compared with those of TS-1 with only micropores. The findings of the research illustrate that with an increase in the molecule volume of the structure-directing agent, there is a decrease in the proportion of the crystalline phase and in the degree of the inclusion of Ti⁴⁺atoms in the structure of the zeolite material. Increase in the volume of the structure-directing agent leads to the decrease of the crystallinity of the samples and decrease in the specific surface area of the material and in the specific volume of micropores. The result of this research will be used to create a theoretical model of controlled micro-/mesoporous ratio in silicas and it may open new perspectives for their potential application in selective oxidation reactions involving large molecules.

7 illus, 3 tables, 29 ref

003945   AKTAS A, CELEPCI D B, GOK Y (Chemistry Dep, Inönü Univ, Malatya- 44280) : Novel 2-hydroxyethyl substituted N-coordinate-Pd(II)(NHC) and bis(NHC)Pd(II) complexes: Synthesis, characterization and the catalytic activity in the direct arylation reaction. J Chem Sci 2019, 131(8), 78.

The direct arylation reaction has attracted attention in recent years especially because of its environment-friendly properties. In this study, we researched the synthesis of 2-hydroxyethyl substituted bis(NHC)Pd(II) complexes and also the synthesis of N-coordinate-Pd(II)(NHC) complexes containing N-bound benzimidazolium from palladium acetate ([Pd(CH₃COO)₂]) with 1,3-disubstituted benzimidazolium halides in DMSO. All the complexes have been characterized by using ¹H NMR, ¹³C NMR, FTIR spectroscopy and elemental analysis techniques. The molecular and crystal structure of one of the complexes is confirmed by using single-crystal X-ray diffraction. These complexes have been examined as the catalyst in the direct arylation reaction with 2-n-butylfuran and 2-n-butylthiophene and have demonstrated excellent activity in this reaction.

2 illus, 6 tables, 62 ref

003978   KONWAR M, ELNAGDY H M F, GEHLOT P S, KHUPSE N D, KUMAR A, SARMA D (Chemistry Dep, Dibrugarh Univ, Dibrugarh- 786 004) : Transition metal containing ionic liquid-assisted one-pot synthesis of pyrazoles at room temperature. J Chem Sci 2019, 131(8), 80.

The feasible and one of the green ways to synthesize organic compounds especially pyrazole and its derivatives are systematically presented. The one-pot synthesis of pyrazole was achieved by condensation of various hydrazines and 1,3-diketone derivatives at room temperature using transition metal-based ionic liquids. Herein, the unique combination of Fe(III) with ionic liquid is explored and utilized as an efficient homogeneous catalyst for the synthesis of pyrazole and its derivatives. The homogenous catalyst thus synthesised was re-used up to the fourth cycle (with 90 %, 88 %, 84 %, 78 % yields respectively).

4 illus, 2 tables, 74 ref

003976   KALAIVANI P, PUSCHMANN H, KAVERI M V, SURESH T, PRABHAKARAN R (Chemistry Dep, Bharathiar Univ, Tamilnadu- 641 018) : One-pot synthesis of new water-soluble binuclear octahedral Ni(II) and mononuclear Ru(II) carbonyl complexes containing 2,6 pyridine dicarboxylic acid. J Chem Sci 2019, 131(8), 81.

An attempt to synthesize mixed geometrical hetero binuclear complexes has been made by reacting 2,6 pyridinedicarboxylic acid with [NiCl₂(PPh₃)₂] and [RuHCl(CO)(PPh₃)₃]. However, the reaction afforded a mononuclear complex [Ru(dipic)(CO)(PPh₃)₂].DMF (1) and homo binuclear complex [Ni₂(dipic)₂(H₂O)₅].2H₂O (2) [dipic = 2,6-pyridinedicarboxylate] respectively. The new complexes (1 and 2) were characterized by elemental analyses, IR, UV-Vis, ¹H-NMR and single-crystal X-ray diffraction studies. The complexes 1 and 2 crystallized in the monoclinic P2₁/c and triclinic P-1 space groups, respectively. Complex 2 displayed a three-dimensional (3D) network with lattice water molecules. The redox behaviour of the complexes was studied by cyclic voltammetry. The DNA and albumin binding studies of the complexes were done by taking CT-DNA and BSA as models. The new complexes exhibited significant binding efficiency with DNA and albumin.

13 illus, 2 tables, 50 ref

003962   DHIVYA R, GOMATHI A, VISWANATHAMURTHI P (Chemistry Dep, Periyar Univ, Tamilnadu- 636 011) : A simple Schiff base platform: Sensing of Al³⁺ ions in an aqueous medium. J Chem Sci 2019, 131(8), 83.

A simple Schiff base probe PADP ((1,2-phenylenebis(azanylylidene)) bis(methanylylidene))bis(3-(diethylamino)phenol) was synthesized from 4-(diethylamino)salicylaldehyde and o-phenylenediamine and has been characterized using analytical and spectral methods. The emission spectrum of PADP Schiff base shows notable enhancement in the emission intensity at 500 nm in the presence of Al³⁺ in MeOH-H₂O (1:9 v/v). On the other hand, other relevant metal ions did not influence considerably the emission spectrum of PADP. The detection limit and binding constant (K_b) of PADP towards Al³⁺ were found to be 0.104 µM and 3.0 × 10⁶ M⁻¹ from the fluorescence titration experiments. The 1:1 binding stoichiometry was further determined by Job^’s plot and ESI-MS spectroscopy. The MTT assay shows no or negligible toxic nature of probe and thus it was utilized in vitro cell imaging studies of Al³⁺ ions. The results show that the probe PADP could be useful to detect Al³⁺ in an aqueous medium.

6 illus, 24 ref

003943   AARJANE M, SLASSI S, TAZI B, MAOULOUA M, AMINE A (Moulay Ismail Univ, Meknes, Morocco) : Novel series of acridone-1,2,3-triazole derivatives: Microwave-assisted synthesis, DFT study and antibacterial activities. J Chem Sci 2019, 131(8), 85.

A series of novel acridones bearing a 1,2,3-triazole unit have been synthesized and characterized. The copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) was performed using both a conventional method and a microwave-assisted synthetic method. The in vitro antibacterial potencies of all the synthesized compounds were determined against five clinically isolated strains: Escherichia coli, Klebsiella pneumonia, Pseudomonas putida, Serratia marcescens and Staphyloccocus aureus. Furthermore, DFT quantum chemical calculations were carried out to investigate geometry structures, frontier molecular orbital and gap energies, and molecular electrostatic potential maps (MEP). Lipophilicities of the studied compounds were also determined.

3 illus, 4 tables, 46 ref

004000   SARKOOHAKI B, ALMASI M, KARIMKHANI M (Applied Chemistry Dep, Malayer Univ, Malayer- 65174) : Theoretical and experimental study of physicochemical behavior of binary mixtures: SAFT and PC-SAFT models. J Chem Sci 2019, 131(7), 53.

The type and magnitude of interactions between diisobutyl ketone (DIBK) and a homologous series of 2-alkanols (2-propanol up to 2-pentanol) are studied in this paper using density and viscosity data. Studies have been carried out in a wide range of temperature (293.15 K to 323.15 K), atmospheric pressure, and in the entire range of composition. The calculated excess molar volumes of the above-mentioned systems are positive, and the viscosity deviations are negative. For the correlation of the density values of binary systems, the statistical association fluid theory (SAFT) and perturbed chain statistical association fluid theory (PC-SAFT) have been used, and the output of two models are compared by average absolute deviation. The results show that the PC-SAFT model is more efficient. Densities and viscosities reported for binary systems along with applied models are all novels, and so far no reports have been investigated in the scientific papers.

4 illus, 1 table, 15 ref

003944   AHER J S, KARDEL A V, GAWARE M R, LOKHANDE D D, BHAGARE A M (Chemistry Dep, B H Commerce and A M Science Coll, Maharashtra- 422 002) : One pot synthesis of pyrimidine-5-carbonitrile and pyrimidine-5-carboxamide using ammonium chloride under solvent free condition. J Chem Sci 2019, 131(7), 54.

Pyrimidine-5-carbonitrile and pyrimidine-5-carboxamide were synthesized from the various substituted benzaldehyde, malononitrile and cyanoacetamide, urea/thiourea in the presence of ammonium chloride followed by characterization using IR, ¹H NMR spectroscopic technique.

1 table, 14 ref

003984   MA X, DU W, LIU W, LIU Y, XIAO T, JIANG Y (Kunming Univ of Science and Technology, Kunming- 650 500) : Metal-free selective aryl C–H formylation co-controlled by 1,2,3-triazole and hydroxyl using DMSO as formyl source. J Chem Sci 2019, 131(7), 55.

A facile and efficient method for direct C–H formylation of phenolated 1,4-disubstituted 1,2,3-triazoles using DMSO as the formyl source has been developed. The reaction proceeded smoothly under metal-free conditions with good functional group tolerance and high selectivity co-controlled by the triazole ring and hydroxyl group.

1 illus, 2 tables, 34 ref

003953   BHAGWAT A A, SEKAR N (Dyestuff Technology Dep, Institute of Chemical Technology, Maharashtra- 400 019) : Investigation of photophysical, structural aspects and nonlinear optical properties of Foron blue SR analogs using Density Functional Theory (DFT). J Chem Sci 2019, 131(7), 56.

Analogs of 2-[(2Z)-2-[[4-(dihexylamino)-2-methylphenyl]methylidene]-1,1-dioxo-1-benzothiophen-3-ylidene]propanedinitrile (Foron blue SR, Disperse Blue 354) are studied in terms of photophysical, structural aspects and its nonlinear optical properties evaluated by using Density Functional Theory (DFT) and Time Dependent Density Functional Theory (TD-DFT). The structures were optimized by using function B3LYP and basis set used was 6-31G(d). Polarizability (αα), first and second order hyperpolarizability (ββ and γγ) was determined by three density functionals B₃LYP, CAM-B₃LYP and BH and HLYP. B₃LYP functional and the basis set 6-311+G(d,p) shows high values of αα, ββ and γγ. The B₃LYP functional gives the highest first order hyperpolarizability value for (Z)-2-(2-(4-(dimethylamino)benzylidene)-1,1-dioxidobenzo[b]thiophen-3(2H)-ylidene)malononitrile (3a) is 373.31×10⁻³⁰ e.s.u and 486.32×10⁻³⁰ e.s.u in ethylacetate and dimethylformamide respectively. Effect of bond length alteration (BLA) and bond order alteration (BOA) on first order hyperpolarizability was evaluated. Intrinsic hyperpolarizability shows the compound (Z)-2-(4-(dimethylamino)benzylidene)benzo[b]thiophen-3(2H)-one 1,1-dioxide (1a) intrinsically good. Perturbation potential is found to decrease as absorption energy deceases and hyperpolarizability increases.

10 illus, 8 tables, 31 ref

003995   SADRAVI S, HONARASA F (Chemistry Dep, Islamic Azad Univ, Shiraz, Iran) : Spectrophotometric nanomolar determination of glucose by using C-dots/Fe₃O₄ magnetic nanozyme. J Chem Sci 2019, 131(7), 58.

C-dots/Fe₃O₄ magnetic nanocomposite was known as peroxidase-like nanozyme. In this work, C-dots/Fe₃O₄ magnetic nanocomposite was used to determine glucose in the presence of glucose oxidase (GOx). The color change of 3,3′′,5,5′′-tetramethylbenzidine (TMB) was used as an indication of glucose in a colorimetric assay. The nanozymatic activity of C-dots/Fe₃O₄ magnetic nanocomposite to detect glucose was depended on TMB and C-dots/Fe₃O₄ nanozyme concentration and pH. The linear range and detection limit to determine glucose using C-dots/Fe₃O₄ magnetic nanocomposite were obtained as 5×10−85×10⁻⁸ to 1×10⁻³M and 50 nM, respectively. Also, the sensing system shows high selectivity towards the detection of glucose in the presence of fructose, lactose and maltose as interferences. The results indicate that this assay is simple, cheap, and highly sensitive and selective for glucose determination.

6 illus, 1 table, 39 ref

004009   UDAYAKUMAR M, CERÓN M, CEBALLOS P, VENKATESAN P, PERCINO M J, THAMOTHARAN S (Bioinformatics Dep, SASTRA Deemed Univ, Thanjavur- 613 401) : A quantitative study of weak noncovalent interactions in two pyridine isomers containing nitrile and thiophene moieties: A combined X-ray and theoretical investigation. J Chem Sci 2019, 131(7), 60.

Single crystals of two pyridine isomers containing cyano and thiophene moieties {systematic names: (Z)-2-(pyridine-2-yl)-3-(thiophen-2-yl)acrylonitrile, C₁₂H₈N₂S, I and (Z)-2-(pyridine-3-yl)-3-(thiophen-2-yl)acrylonitrile, C₁₂H₈N₂S, II} were obtained from ethanol-cyclohexane mixture. The thiophene ring was found to be disordered over two orientations (syn and anti) in II. The potential energy surface scan of thiophene ring rotation suggests that the syn conformer is more stable by ≈4kcal mol−1≈4kcal mol−1 than that of the anti-conformer. The optimized structures obtained using the DFT method (M06-2X/cc-pVTZ level of theory) show a high degree of similarity with the experimental structures. A detailed experimental and theoretical analysis on the intra- and intermolecular interactions observed in these structures is reported. The molecules arranged in the crystalline state are completely different in I and II. Intermolecular interactions are qualitatively analyzed using Hirshfeld surface and its associated 2D fingerprint plots. The intermolecular interaction energies of different molecular pairs are calculated using the PIXEL method. Several weak non-covalent interactions such as C–H ⋅⋅⋅N⋅⋅⋅N, C–H ⋅⋅⋅π⋅⋅⋅π, C–H ⋅⋅⋅S⋅⋅⋅S, π⋅⋅⋅ππ⋅⋅⋅π and S⋅⋅⋅NS⋅⋅⋅N contacts play a vital role in the stabilization of crystal structures. These interactions are further explored by the topological analysis of the electron density based on the quantum theory of the atoms-in-molecules approach.

5 illus, 6 tables, 51 ref

003977   KAMYABI M A, QARATAPEH K E, JADALI S, MOHARRAMNEZHAD M (Chemistry Dep, Zanjan Univ, Zanjan, Iran) : Decorating the carbon felt electrode with polymeric platinize nanocomposite: Characterization and electrocatalytic activity towards methanol oxidation reaction. J Chem Sci 2019, 131(7), 61.

Herein, carbon felt (CF), a porous carbonaceous material is used as an anode in a direct methanol fuel cell (DMFC) application. In order to enhance the electrochemical activity of this electrode, modification of the CF electrode is performed with a polymeric-platinize nanocomposite by a pure electrochemical method. In the modification process, 4-methyl-1,2-diaminobenzene is electropolymerized on the CF surface and then, Pt nanoparticles are electrodeposited on this substrate. Physical characteristics of the synthesized nanocomposite, Pt/p-MDAB/CF, are investigated by field emission scanning electron Microscopy and energy-dispersive X-ray spectra. The electrochemical studies such as cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy prove the Pt/p-MDAB/CF superiority over Pt/CF towards methanol oxidation. This superiority that results from the cooperation effect between carbonaceous-polymeric layer and Pt nanoparticles, introduces Pt/p-PDAB/CF as the suitable candidate anode for methanol oxidation reaction (MOR).

3 illus, 52 ref

004004   SOMASHEKARA B, THIPPESWAMY B, VIJAYAKUMAR G R (Chemistry Dep, Tumkur Univ, Karnataka- 572 103) : Synthesis, antioxidant and α-amylase inhibition activity of naphthalene-containing 2,4,5-trisubstituted imidazole derivatives. J Chem Sci 2019, 131(7), 62.

A series of naphthalene ring containing 2,4,5-trisubstituted imidazole derivatives (2a–2l) were synthesized using one-pot multicomponent reaction. The reactions were carried out using naphthaldehyde and substituted benzil in the presence of ammonium acetate in acetic acid media. All newly synthesized imidazole derivatives were characterized by FT-IR, ¹H NMR, ¹³C NMR and mass spectral analysis. Newly synthesized imidazole derivatives were screened for their in-vitro antioxidant activity by DPPH free radical scavenging assay method and αα-amylase inhibition activity by DNS method. All the compounds showed excellent αα-amylase activity at 10, 50 and 100 μg/mL and compounds 2d, 2g, 2k exhibited good antioxidant activity.

2 illus, 34 ref

004001   SEN P (Chemistry Dep, Rhodes Univ, South Africa- 6140, Email: sen_pinar@hotmail.com) : A highly fluorescent tri-nuclear boron complex with large Stokes shifts based on tripodal Schiff base: Synthesis and photophysical properties. J Chem Sci 2019, 131(7), 63.

In this study, a new imine-based tripodal ligand and its difluoroboron complex were designed and synthesized. This trinuclear-boron complex was prepared for the first time and fully characterized by common spectroscopic techniques such as ¹H-NMR, ¹³C-NMR, FT-IR, UV–Vis and MS analysis. The optical and fluorescence properties of complex were examined in CHCl₃, THF, acetonitrile, EtOAc, DMF and DMSO. It was revealed that the obtained boron complex showed intense emission with large Stokes shifts in the range from 83 nm to 96 nm. As a result of quantification of fluorescence quantum yields, it has been observed that it has high quantum yield values up to 48 %. The large Stokes shifts and high efficient emissions in the solutions of boron complex make it precious fluorophore for potential applications in materials science.

5 illus, 32 ref

003985   MADDIREDDY N V, GODBOLE H M, SINGH G P, KINI S G, SHENOY G G (Lupin Limited, Maharashtra- 412 115) : Catalytic asymmetric oxidation of sulfides to sulfoxides using (R)-6,6′-Diphenyl-BINOL as a chiral ligand. J Chem Sci 2019, 131(7), 64.

The chiral metal complex produced in situ from (R)-6,6′′-Diphenyl-BINOL and Ti(O−i−Pr)₄ as a catalytic system for asymmetric sulfoxidation of aryl methyl and aryl benzyl sulfides in the presence of 70 % aqueous TBHP as the oxidant has been investigated. The influence of variation of reagents mole ratios, temperature, solvent and oxidant was examined, and the optimized conditions were then used to oxidize a number of aryl methyl and aryl benzyl sulfides, producing sulfoxides in high enantiopurities (up to 90 % ee) and good yields (up to 81 %).

4 tables, 26 ref

004010   VENKATESH S, YADAV P K, RAMANA M M V (Chemistry Dep, Mumbai Univ, Mumbai- 400 098) : Mesomorphic behavior of methanesulfonate salts of esters of L-Methionine and their optical properties. J Chem Sci 2019, 131(7), 65.

A set of methanesulfonate salts of esters of (S)-2-Amino-4-(methylthio)butanoic acid [L-Methionine] and fatty alcohols have been synthesized in good yields by a green protocol involving a one-step and solvent-free approach. All derivatives have been evaluated for their liquid crystalline properties using polarizing optical microscopy and differential scanning calorimetry and found to be enantiotropic liquid crystals. Refractive indices were measured for one of the derivatives at different temperatures and wavelengths. It exhibited a high Abbe number and low dispersive power.

5 illus, 2 tables, 32 ref

003979   KOTHA S, ALI R (Chemistry Dep, Indian Institute of Technology-Bombay, Mumbai- 400 076) : A simple synthetic strategy to π-conjugated spirofluorenes. J Chem Sci 2019, 131(7), 66.

We have developed a simple synthetic strategy to spirofluorene derivatives via ring-closing metathesis and Suzuki–Miyaura cross-coupling reactions as key steps. To this end, we have used readily available starting materials to generate a library of spirofluorene derivatives under mild reaction conditions.

1 illus, 14 ref

003986   MAHAJAN D P, GODBOLE H M, SINGH G P, SHENOY G G (Lupin Limited, Pune- 412 115) : Enantioselective Michael addition of malonic esters to benzalacetophenone by using chiral phase transfer catalysts derived from proline-mandelic acid/tartaric acid. J Chem Sci 2019, 131(7), 67.

Herein, we have explored the enantioselective Michael addition of various malonate esters to benzalacetophenone by successful utilization of chiral phase transfer catalysts derived from proline, mandelic acid and tartaric acid under mild phase transfer conditions. The obtained results signify that these chiral phase transfer catalysts are efficacious towards enantioselective Michael addition as the use of it resulted in good enantioselectivity and appreciable chemical yields.

4 illus, 6 tables, 21 ref

003990   OKONKWO B O, AFIEROHO O E, AHANONU E D, OKWUBIE L, ABO K A (Pharmacognosy and Phytotherapy Dep, Port Harcourt Univ, Port Harcourt, Nigeria, Email: ozadheoghene.afieroho@uniport.edu.ng) : Pleurotus pulmonarius (Fr.) Quel. (Pleurotaceae): In vitro antioxidant evaluation and the isolation of a steroidal isoprenoid. J Appl Biol Biotechnol 2019, 7(4), 32-8.

This study is reporting the in vitro antioxidant activity of the fruiting body of the edible mushroom Pleurotus pulmonarius (Fr.) Quel. The fruiting body of the edible mushroom was defatted with n-hexane and further extracted by successive maceration in dichloromethane (DCM) and 80 % aqueous ethanol (AQE) to obtain the DCM and AQE extracts, respectively. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and iron chelating assays were used for antioxidant evaluation in vitro with ascorbic acid as the reference standard for comparison. Isolation and structural elucidation of the steroid were done using chromatographic and spectroscopic techniques, respectively. The trend for the DPPH radical scavenging activity: ascorbic acid [inhibition concentration (IC)₅₀ = 0.012 mg/ml] > AQE (IC₅₀ = 0.525 mg/ml) > DCM (IC₅₀ = 1.820 mg/ml) and for the iron chelating activity: ascorbic acid (IC50 = 0.214 mg/ml) > AQE (IC₅₀ = 1.318 mg/ml) > DCM (IC50 = 7.586 mg/ml) were observed. From the DCM was isolated a pure compound 1 elucidated to be the known steroidal isoprenoid: ergosta-5, 7, 22-trien-3β-ol. This study aside reporting the isolation of the known compound 1 from this species of Pleurotus, has also shown that compound 1 has a significant iron chelating activity at 0.001 mg/ml of 77.06 % compared to 4.56 % at same concentration for DPPH scavenging activity.

6 illus, 1 table, 22 ref

004006   THASNEEM Z A, ARAVINDH K, FENCIA M J M, KUMAR C N, PAVITHRA T, RAJKUMAR K, SURENDRAN S, VIDHYA M, MAHESH R, RAMALAKSHMI S (Microbiology Dep, Sri Moogambigai Arts and Science Coll for Women, Dharmapuri- 636 805, Email: arulaksh24@gmail.com) : GC-MS analysis of yellow pigmented Macrococcus equipercicus isolated from alfalfa rhizosphere soil fields of Coimbatore. J Appl Nat Sci 2019, 11(3), 645-9.

The rhizosphere of plant possesses important microflora, which secretes wide chemical compounds including secondary metabolites necessary for plant growth and development. The microbial flora of alfalfa plant rhizosphere soil region was explored for functional activity and we found upto ten different pigmented colonies. Due to good functional diversity, this yellow pigmented colony was taken for further studies. Thus, the culture was molecularly characterized and identified for potent bioactive components responsible for antimicrobial activity. The selected culture mass was cultured and secondary metabolites were produced and extracted using ethyl acetate and subjected to GC-MS analysis. The antimicrobial study revealed selective activity against Streptococcus pneumonia, and Proteus sp with zone of inhibition to be 18 and 20 mm respectively. Molecular identification of the isolate by 16S rRNA sequencing showed the isolate as Macrococcus equiper-circus with 100 % similarity. Based on GC-MS analysis report 25 bioactive compounds were identified and 13-docosenamide, hexadecanoic acid esters and quercetin were found in ethyl acetate extract. Thus the yellow-pigmented gram-positive cocci M.equipercicus isolated from Medicago sativa possessed wide antibacterial activity due to presence of quercetin. Through the studies, we were able to identify potent antibacterial compound-producing bacteria from M. Sativa plant rhizosphere soil.

4 illus, 2 tables, 11 ref

003965   EL-DAHMY S I, ABDEL-GHANI A E, ATTIA R A, ABOUELENEIN D D (Pharmacognosy Dep, Zagazig Univ, Zagazig, Egypt) : Chemical composition and biological activities of the essential oil of Tanacetum sinaicum Del. grown in Egypt. J Pharmacogn Phytochem 2019, 8(4), 326-31.

Tanacetum sinaicum, family Asteraceae is a wild plant indigenous to Egypt and grows on the rocky slopes of Sinai. Because of the large variation observed between the previous reports concerning the essential oil constituents. The present work aimed to perform a detailed investigation of the chemical composition of essential oil from T. sinaicum. Furthermore, the present study represents the first report about cytotoxic and antioxidant activities of essential oil of this plant. The essential oil was subjected to GC-MS analysis which resulted in identification of 41 constituents representing 85.81 % of its total composition. The biological activity of the oil showed moderate cytotoxic activity against human hepatocellular carcinoma, colon carcinoma and human lung cancer cell lines. In addition, the antioxidant activity was investigated using the DPPH free radical assay and the results indicated that the oil has strong antioxidant activity. Furthermore, the insecticidal activity on culex pipiens mosquitoes was measured using the immersion method, the oil showed high mortality percentages for the larval, pupal and adult stages. The antimicrobial results indicate that the oil has a positive activity against the gram negative bacteria Proteus vulgaris and gram positive bacteria Bacillus subtilis. Also, it has some activity against Escherichia coli and Staphylococcus aureus.

6 illus, 3 tables, 27 ref

003966   EVANGELIN M P, PAVANI Y, KUMAR P, MONICA K, VENNI D, SUKEERTHIKA S U, ANUSHA A R (Pharmaceutical Chemistry Dep, Southern Institute of Medical Sciences, Guntur, Andhra Pradesh) : An updated review on 1, 2, 4 triazoles. J Pharmacogn Phytochem 2019, 8(4), 292-9.

The heterocyclic are attaining their importance as being the centre of activity. The nitrogen containing heterocyclic are found in abundance in most of the medicinal compounds. The success of imidazole as an important moiety of number of medicinal agents led to introduction of the triazoles. The triazoles are said to be the isosters of imidazoles in which the carbon atom of imidazole is isosterically replaced by nitrogen. Triazoles are 5-membered rings, which contain two carbon and three nitrogen atoms. According to the position of nitrogen atoms the triazoles are exists in isomeric forms.

58 ref

003991   PAUL M K, EVANGELIN M P, PHANIDEEP V, PRAKASH M J, SUHANA S J, BABU S M (Chemistry Dep, Rajiv Gandhi Univ of Knowledge Technologies, Nuzvid, Andhra Pradesh) : Recent advantages in benzofurans. J Pharmacogn Phytochem 2019, 8(4), 287-91.

Benzofuran as an important heterocyclic compound is extensively found in natural products as well as synthetic materials. Since benzofuran drivatives display a diverse array of pharmacological activities, an interest in developing new biologically active agents from benzofuran is still under consideration. This review highlights recent findings on biological activities of benzofuran derivatives as antimicrobial and antibreast cancer agents and lays emphasis on the importance of benzofurans as a major source for drug design and development.

36 ref

003988   MAMANI R, ALHAJI N M (Chemistry P.G. Dep, Bon Secours Coll for Women, Thanjavur, Tamil Nadu) : GC-MS analysis of phytocomponents in methanolic extract of Coleus aromaticus. J Pharmacogn Phytochem 2019, 8(4), 106-9.

Plants have been an important source of medicine with qualities for thousands of years. Phytochemicals are the chemicals extracted from plants. These organic chemicals are classified as primary or secondary constituents, depending on their role in plant metabolism. GC-MS method used for the analysis of the obtained extract can be an interesting tool for testing the amount of some active principles in herbs used in various industries. The aim of this study was to carry out for identification of bioactive compounds from the leaves methanolic extract of Coleus aromaticus by Gas chromatography and Mass spectroscopy (GC-MS). GCMS analysis of methanolic extract was done by standard protocol using the equipment Perkin-Elmer Gas Chromatography–Mass Spectrometry, while the mass spectra of the compounds found in the extract was matched with the National Institute of Standards and Technology (NIST) library. The GC-MS analysis revealed the presence of various compounds like 1,2-benzenedicarboxylic acid, diethyl ester, Phytol, Octadecenal, Dibutyl phthalate, 2-hexadecen-1-ol, 3,7,11,15-tetramethyl, hexadecanoic acid, methyl ester, oleic acid, 9,12,15-octadecatrienoic acid, 9,12,15-Octadecatrienoic acid, ethyl ester and solanesol in the methanolic extract of Coleus aromaticus. These findings support the traditional use of Coleus aromaticus in various disorders.

1 illus, 2 tables, 14 ref

003975   JAYALAKSHMI P, DEVIKA P T (Biochemistry Dep, Mohamed Sathak Coll of Arts and Science, Chennai, Tamil nadu) : Assessment of in vitro antioxidant activity study of polydatin. J Pharmacogn Phytochem 2019, 8(4), 55-8.

Polydatin is a monocrystalline segregated from polygonum cuspidatum sieb et zucc. Polydatin also named piceid (3͵4'͵5-trihydroxystilbene-3-β-D glucoside͵PD). Polydatin is also detected in grapes, peanut, hopcons, redwines and hop pellets. Umpteen pharmacological exploration of polydatin mainly focus on cardiovascular effects, neuroprotection, immunoregulatory effects, anti –inflammatory, antioxidation, anti-tumor. In our present study was to evaluate the antioxidant activity of polydatin. Antioxidant activity of polydatin determined by four different invitromethods.They are1,1 diphenyl-2- picrylhydrazlradical (DPPH·),2,2-azino-bis-(3-ethylbenzothiazoline-6-sulphonate) radical cation (ABTS·), hydroxyl radical (OH·) and superoxide anion radical (O₂·־) established the free radical scavenging and antioxidant activity of polydatin.

4 illus, 4 tables, 16 ref

003946   ANTIL R, SINGH L, GAHLAWAT D K, DAHIYA P (Botany Dep, Maharshi Dayanand Univ, Rohtak, Haryana) : Investigation of chemical composition of methanolic extract of Anisomeles indica (L.) Kuntze by using FTIR and GC-MS. J Pharmacogn Phytochem 2019, 8(4), 49-54.

Anisomeles indica (L.) Kuntze (Lamiaceae) is camphor scented perennial weed have brush leaves. Traditionally, the plant has been used as folk medicine to cure fever, whooping cough, uterine infection, allergy, snake bite, liver protection, mouth abscess and toothache. Plant extract from aerial parts of A. indica prepared in Soxhlet assembly. Screening for phyto chemicals was carried out as per standard methods. FTIR and GC-MS analysis of the methanolic extracts of A. Indica was performed. FTIR results find out the major peaks between ranges of 952 cm^-1 to 3430 cm^-1 . FTIR peak spectrum indicated the presence of alcohols, alkanes, alkyl halides, unsaturated hydrocarbons, fatty acids, amines, acid anhydride and carboxylic compounds. GC-MS chromatogram of methanolic extract showed the presence of 14 phyto compounds. Out of 14 compound, three compounds have high percentage of Cyclohexane,1-ethnyl-1-methyl-2,4-bis(1-methylethyl)-[1S-(1-alpha,2-bet-(21.98), Caryophyllene (27.68), Naphthalene,1,2,3,4,4a,5,6,8a-octahydro-4a,8-diemthyl-2-methylethenyl) (25.98) and the low percentage of Bicyclo[7.2.0]undec-4-ene,4,11,11-trimethyl-8-methylene(0.406). Mainly terpenoids have been detected from the methanolic extract of this plant most of which are sesquiterpenes. Others are alkaloids and phenols. Sesquiterpenes display antimicrobial, anti-inflammatory, and anti-cancerous property. Present investigation reveals the presence of bioactive compounds in the methanolic extract, which have of phyto pharmaceutical significance.

2 tables, 33 ref

003961   DAS M, BANERJI A, DIXIT A K, RAO M M (Institute for Drug Development, Kolkata, West Bengal) : Phytochemical analysis and HPTLC fingerprinting profile of roots of Alstonia scholaris (L.) R.Br (Saptaparṇa). J Pharmacogn Phytochem 2019, 8(4), 15-23.

Plants are rich sources of bioactive compounds, and have been used in traditional medicine systems for the past few millennia; even now plant-based drugs continue to provide new remedies to mankind. The medicinal plant Alstonia scholaris (L.) R. Br. (Saptaparṇa, Chhatim) is widely used in the Indian school of traditional medicine of Ayurveda. The present study reports phytochemical studies and HPTLC fingerprinting profile of Alstonia scholaris roots. These results provide referential parameters for identification of this drug.

6 illus, 4 tables, 26 ref

003980   KOUAME B K F P, KABLAN L, KABRAN A F, ADIKO N M, AKOUBET O A, DIOMANDE G G D, AKPA S J, BEDI G, TEA I, ROBINS R, et al. (Felix Univ, Abidjan 22, Cote d’Ivoire) : A novel anthraquinone from Morinda lucida Benth (Rubiaceae). J Pharmacogn Phytochem 2019, 8(4), 11-4.

Morinda lucida (Rubiaceae) is a plant used in West African’s traditional medicine for the treatment of various diseases. The Phytochemical investigation of its stem barks led to the isolation of eight anthraquinone derivatives. Among these compounds, one is a new structure: 2-acetyl-1- hydroxyanthraquinone (8). The others were known from this plant: damnacanthal (1), 3-hydroxy-2- carbaldehyde-anthraquinone (2), 1-hydroxy-2-methyl-anthraquinone (3), nordamnacanthal (4), rubiadin1-methyl ether (5), morindone (6), tectoquinone (7). Their structures were established according to their spectral data (NMR 1D and 2D, MS).

1 illus, 1 table, 14 ref

003963   DUAN L, MA Q, DAI X, WANG B, MA L, DONG L, ZHANG B (Army Engineering Univ of PLA, Nanjing- 210 007, People’s Republic of China, Email: 850082427@qq.com) : Structural evolution and CO₂ capture performance of silicon oxycarbide-derived carbon by thermal-treatment under an Ar atmosphere. Bull Mater Sci 2019, 42(4), 182.

In this paper, we investigated the effect of thermal-treatment under an Ar atmosphere on the structural evolution of silicon oxycarbide-derived carbons (SiOC-DCs) by adjusting the temperature from 1200 to 2100^◦C, which will be characterized by means of N₂ adsorption, X-ray diffraction, Raman and transmission electron microscopy techniques, and studied their CO₂ capture performances. The results show that the structure of SiOC-DCs varied regularly with treatment temperature. The porosity and crystallinity of the as-received sample are almost stable when the thermal-treatment temperature is <1500^◦C. Subsequently, increasing the temperature (especially up to 1800^◦C) will lead to an obvious improvement in the carbon crystallinity at the cost of pore structure breakage, which can be characterized by a quick decrease in the surface area and total pore volume of SiOC-DCs. Interestingly, the as-received SiOC-DC sample exhibits good CO₂ capture performance at 0^◦C under ambient pressure, up to 3.16 mmol g⁻¹. The thermal-treatment process under an Ar atmosphere in the range of 1200–1500^◦C could further help in increasing the CO₂ adsorption ability by increasing the ultra-micropore (d < 0.6 nm) volume.

6 illus, 2 tables, 28 ref

003996   SAEED U, ABDEL-WAHAB M S, SAJITH V K, ANSARI M S, ALI A M, AL-TURAIF H A (Chemical and Materials Engineering Dep, King Abdul Aziz Univ, Jeddah 21589, Kingdom of Saudi Arabia, Email: usman144de@yahoo.com) : Characterization of an amorphous indium tin oxide (ITO) film on a polylactic acid (PLA) substrate. Bull Mater Sci 2019, 42(4), 175.

The study presents the deposition of nanostructured indium tin oxide thin films with thicknesses of 10, 30 and 50 nm on the polylactic acid (PLA) substrate by sputtering at 30^◦C. The absence of ITO peaks on the X-ray diffraction patterns confirms the amorphous state of ITO films and the X-ray photoelectron spectroscopy spectrum validates the deposition of ITO films on the PLA substrate. The results of atomic force microscopy of films exhibit variation in the average roughness of 0.3–1.5 nm when the thickness is increased. It was examined that optical transmission is dependent on the thickness of films which varies from 78 to 87 % in the visible spectrum of 400–700 nm and the energy band gap varies from 3.95 to 4.02 eV. The films exhibit the low sheet resistance which is due to the formation of oxygen vacancies and dangling bonds. An increase in transmittance enhances the FOM of the ITO films on the PLA substrate.

10 illus, 3 tables, 30 ref

003974   IVANENKO I, VORONOVA A, ASTRELIN I, ROMANENKO Y (Inorganic Substances Technology Dep, National Technical Univ of Ukraine, Kyiv 03056, Ukraine, Email: irinaivanenko@hotmail.com) : Structural and catalytic properties of Ni–Co spinel and its composites. Bull Mater Sci 2019, 42(4), 172.

Pure nickel–cobalt (Ni–Co) spinel and its two composites with active carbon and multi-walled carbon nanotubes (MWCNTs) were synthesized. X-ray diffraction confirmed the nickel cobaltites of cubic syngony and lattice constants for nanosized crystallites. Fourier transform infrared spectra confirmed an inverse spinel consisting of a tetrahedral site Co²⁺ and octahedral sites Ni²⁺ and Co²⁺. Scanning electron microscopy images demonstrated a surface texture typical for spinels and agglomerates of composite particles with active carbon and MWCNTs. All the synthesized samples have a surface area and porosity that are sufficient for the flow of heterogeneous catalytic processes. The micropore volume of the composite with MWCNTs constituted only 4 % of the total porosity, while this percentage represented 25 % for the composite on the basis of active carbon. The high catalytic activity of Ni–Co spinel is proved in the model reaction of borohydride hydrolysis. To create composite spinel catalysts, active carbon showed itself to be a more efficient carrier for the catalytically active mass of spinel, as compared to MWCNTs.

6 illus, 3 tables, 57 ref

003989   NAKONIECZNA P, WIERZBICKI L, WRÓBLEWSKI R, PLOCINSKI T, LEONOWICZ M (Warsaw Univ of Technology, Warsaw, Poland, Email: Paulina.Nakonieczna.dokt@pw.edu.pl) : The influence of carbon nanotube addition on the properties of shear thickening fluid. Bull Mater Sci 2019, 42(4), 162.

The properties of shear thickening fluid (STF), based on polypropylene glycol and amorphous silica, modified by the addition of multiwalled carbon nanotubes (MWCNTs), were studied. The STF’s viscosity increases abruptly during impact tests. The addition of a small amount of carbon nanotubes (CNTs) to the STF, leads to an increase of the maximal viscosity from 2128 to 12,213 Pa·s. To show the differences between various compositions, the microstructures of fluids were observed by scanning electron microscopy. A pronounced influence of the CNTs on the ability of impact force absorption was noticed. The protective structure containing 55 and 0.25 vol % of fumed silica and CNTs, respectively, is able to absorb up to 74% of impact force.

3 illus, 1 table, 13 ref

003972   HEYL H, HOMA D, PICKRELL G (Materials Science and Engineering Dep, Virginia Polytechnic Institute and State Univ, Blacksburg, VA 24060, USA, Email: hanna291@vt.edu) : Reaction of YBa₂Cu₃O_7−x (YBCO) and fused silica in YBCO glass fibres. Bull Mater Sci 2019, 42(4), 154.

This work introduces the first reported experiments on drawing YBa₂Cu₃O_7−x (YBCO) into fibres with a fused silica cladding using a fibre draw tower to manufacture YBCO glass fibres. These fibre draw experiments allowed manufacturing fibre sections with core diameters between 50 and 200 μm and a length of around 1.2 m. However, reactions between the fused silica cladding and the YBCO core were revealed by the fibre drawing process. Therefore, this study focusses on investigating these reactions (in as-drawn fibres as well as after additional heat-treatments) using energy dispersive spectroscopy analyses on an environmental scanning electron microscope as well as using X-ray photoelectron spectroscopy analyses and a cross-polarized light study. The results showed the formation of silica precipitations inside the as-drawn YBCO core, forming an interface layer between the core and the cladding regions, as well as the presence of a high silicon content inside the core with a possible silicate formation. Additional heat-treatments have shown the formation of silica and copper oxide co-precipitations at 900^◦C. In addition, heat-treatments at higher temperatures have shown the occurrence of further reactions, which led to a degradation of the core and the formation of new phases.

11 illus, 4 tables, 30 ref

003957   CHEN J, ZHANG Q-Z, HOU Z-S, JIN F-L, PARK S-J (Chemistry Dep, Inha Univ, Incheon 402-751, Korea, Email: sjpark@inha.ac.kr) : Preparation and characterization of graphite/thermosetting composites. Bull Mater Sci 2019, 42(4), 153.

Graphite/thermosetting composites were prepared via a melt blending and compression–curing process using epoxy and phenolic resins as polymer matrices. The flexural strength, flexural modulus and electrical conductivity of the composites were investigated. The composites containing 55 wt% graphite showed the maximum flexural strength and modulus. Scanning electron microscopy results showed that the thermosetting resins and graphite were uniformly dispersed on the fractured surface of the composites. The electrical conductivity of the composites increased with an increase in the graphite content. The flexural and electrical properties of the composites improved significantly by the addition of a carbon fibre cloth (CFC) or a CFC and carbon nanotubes.

5 illus, 1 table, 33 ref

003958   CHOI Y-K, KIM K M, JANG Y, JEONG H, SINGH V, RANGARAJULU S K (Biological Engineering Dep, Konkuk Univ, Seoul 05029, Korea, Email: kumaran.ran@gmail.com) : Investigations on the ZnO- and Cr-doped ZnO powders. Bull Mater Sci 2019, 42(4), 150.

Among the metal–oxide nanoparticles, pure and doped zinc oxide (ZnO) has been widely studied due to their potential applications, such as electrical, thermal and optical materials. In this context, samples of undoped ZnO and Cr-doped ZnO powders were prepared using a solution-combustion route. The formation of the combustion products was confirmed by X-ray diffraction analysis. The samples were well characterized using the Fourier transform infrared spectroscopy and scanning electron microscopy techniques. In the sample, photoluminescence studies showed that ZnO could be excited at 267 nm, while an ultraviolet emission centred at ∼383 nm was exhibited. Antibacterial-activity testing was carried out using the disc-diffusion method.

5 illus, 1 table, 41 ref

003947   AZIZ W J (Physics Dep, Mustansiriyah Univ, Baghdad 00964, Iraq, Email: wisamj.aziz@uomusttansiriyah.edu.iq) : Synthesis of CdSe and CdSe:Ga nanostructures for antibacterial application. Bull Mater Sci 2019, 42(4), 148.

In this paper, the preparation of CdSe and CdSe:Ga nanoparticles using two methods: thermal evaporation and pulse laser ablation has been reported. Their structural properties were characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). As confirmed by the XRD curves, CdSe and CdSe:Ga nanoparticles exhibited polycrystalline and wurtzite hexagonal structures with orientation planes of (100), (101), (102), (110) and (112). Also, a homogeneous distribution of nano-rod, flower-like, cylindrical, hexagonal and both nano-rod and hexagonal shapes with different diameters was seen by FESEM images. The band gaps of CdSe and CdSe:Ga (without annealed and annealed at temperatures of 150 (6 h) and 500^◦C (1 h)) were found to be 1.72, 1.7, 1.69 and 1.64 eV, respectively. The antibacterial activity could be increased by annealing CdSe:Ga nanoparticles at 150^◦C for 6 h in Gram-positive bacteria (Bacillus subtilis), whereas it is decreased in Gram-negative bacteria (Enterobacter cloacae). Alternatively, annealing CdSe:Ga at 500^◦C for 1 h led to an increase in the antibacterial activity in both Gram-positive and Gram-negative bacteria. It is concluded that the antibacterial activity is highly dependent on the type of bacteria, material, preparation conditions and the used methods.

5 illus, 3 tables, 16 ref

003951   BARUAH S, KUMAR S, PUZARI A (National Institute of Technology Nagaland, Dimapur, Nagaland - 797 103, Email: amrit09us@yahoo.com) : Surfactant modulated structural modification of hybrid poly(p-phenylenediamine)/titanium dioxide composites and investigation of their functional behaviour. Bull Mater Sci 2019, 42(4), 146.

Hybrid polymer materials obtained by combining functional polymers with metal oxides are important functional materials having significant technological implications. Herein, we have described surfactant modulated structural manipulation of hybrid poly(p-phenylenediamine)/TiO₂ composites using oleic acid as the surfactant molecule and investigated functional utility of the polymer composites. Hybrid polymer composites were synthesized by an oxidative polymerization technique using H₂O₂ as the oxidant and chloroglycinato(1,10-phenanthroline) copper(II) monohydrate as the catalyst. Structural characterization was performed by using conventional techniques like Fourier-transform infrared, ultraviolet–visible spectroscopy, photoluminescence, X-ray diffraction and thermogravimetric analysis. The effect of structural modification on the functional behaviour of the hybrid polymer composites was investigated and important observations were noted. Structural modification of the hybrid polymer composites significantly improved the mechanical and thermal characteristics. Conductivity values obtained from I –V measurement and band gap calculation indicate that there is scope for using such materials as wide band gap semiconductor materials and also as insulator materials.

10 illus, 2 tables, 36 ref

003973   IRFAN A, AL-SEHEMI A G, ASSIRI M A, MUMTAZ M W (Chemistry Dep, King Khalid Univ, Abha 61413, Saudi Arabia, Email: irfaahmad@gmail.com) : Exploring the electronic, optical and charge transfer properties of acene-based organic semiconductor materials. Bull Mater Sci 2019, 42(4), 145.

In order to tune the optoelectronic and charge transfer properties of 4,6-di(thiophen-2-yl)pyrimidine (1), some new compounds were designed, i.e., 4,6-bis(benzo[b]thiophen-2-yl)pyrimidine (2), 4,6-bis(naphtho[2,3-b]thiophen-2- yl)pyrimidine (3), 4,6-bis(anthra[2,3-b]thiophen-2-yl)pyrimidine (4), 4,6-bis(tetraceno[2,3-b]thiophen-2-yl)pyrimidine (5) and 4,6-bis(pentaceno[2,3-b]thiophen-2-yl)pyrimidine (6). Compounds 2–6 were designed by assimilation of benzene, naphthalene, anthracene, tetracene and pentacene, respectively at both ends of compound 1. Integration of oligocene end cores reduces the energy gap resulting in a red shift in the absorption and fluorescence emission spectra. The legible intra-molecular charge transfer is significant from electron-rich moieties to the electron-deficient core (pyrimidine). The elongation of π-conjugation led to escalate the electron affinity, lower the ionization potential and hole reorganization energy. The hole reorganization energies of compounds 3–6 exposed that these materials would be effective hole transport contenders to be used in diverse semiconductor devices.

5 illus, 61 ref

003970   HASTUTI B, SISWANTA D, MUDASIR, TRIYONO (Chemistry Education Dep, Sebelas Maret Univ, Surakarta 57126, Indonesia, Email: Budihastuti@staff.uns.ac.id) : Kinetic and thermodynamic biosorption of Pb(II) by using a carboxymethyl chitosan–pectin–BADGE–Pb(II)-imprinted ion polymer adsorbent. Bull Mater Sci 2019, 42(4), 143.

Pb(II)-imprinted pectin-carboxymethyl chitosan-BADGE or Pb(II)-CPB was synthesized by mixed pectin (Pec) and carboxymethyl chitosan (CC) and then crosslinked with a crosslinking agent bisphenol A diglycidyl ether (BADGE) to form a stable adsorbent and resistant to acidic media. As a first step, the synthesis was performed by reacting the –OH group among Pec and CC with BADGE to form CPB. The Pb(II) ion was then imprinted with the Pec–CC gel and formed Pb(II)-CPB. Furthermore, the release of Pb(II) ions from the adsorbent was performed using the chelating agent, Na₂EDTA. The kinetic and thermodynamic equilibrium of the batch sorption of Pb(II) onto Pb(II)-CPB were investigated. The results of this study showed that the adsorption process of the Pb(II)-CPB adsorbent could be well described by the pseudo-second order model. The thermodynamic biosorbent in adsorption of the Pb(II) ion follows Freundlich isotherm. The adsorption energy of the adsorbent was 15.59 kJ mol⁻¹. This proves that the mechanism process of the adsorbent to Pb(II) ions occurs by physical adsorption. The Pb(II)-CPB adsorbent shows a significantly higher capacity compared to Pec and chitosan. Adsorption capacity of Pb(II)-CPB was 664.44 × 10⁻³. The Pb(II)-CPB adsorbent has higher selectivity on Pb²⁺ ions compared to Pec and CC with the adsorption selectivity order Pb(II)/Zn(II) < Pb(II)/Cu(II).

4 illus, 3 tables, 12 ref

003987   MALAN R C, VORA A M (Applied Science and Humanities Dep, Government Engineering Coll, Valsad - 396 001, Email: rcmgecv@gmail.com) : Study of collective motion in liquid alkali metals. Bull Mater Sci 2019, 42(4), 139.

Study of collective motion in the liquid alkali metals is provided through the current article. Phonon dispersion curves for liquid alkali metals are presented using a second order approach in conjunction with the Hubbard–Beeby (HB) equation. Both longitudinal and transverse components of the collective motion are obtained through the present model. A classical approximation approach of the pseudopotential is used to describe the core interaction of the electronic configuration. Screening as well as exchange and correlation effect are determined by local field correction functions given by Hartree (H), Ichimaru–Utsumi (IU) and Sarkar et al (S). Related parameters and constants are reported in line with the current computation to make the study comprehensive.

3 illus, 2 tables, 42 ref

004007   TORRES-LUNA J A, GIRALDO-GÓMEZ G I, SANABRIA-GONZÁLEZ N R, CARRIAZO J G (Química Dep, Colombia Nacional Univ, Bogotá, Colombia, Email: jcarriazog@unal.edu.co) : Catalytic degradation of real-textile azo-dyes in aqueous solutions by using Cu–Co/halloysite. Bull Mater Sci 2019, 42(4), 137.

Catalytic degradation of textile dyes in diluted aqueous solutions with minimal consumption of energy is a great challenge for wastewater treatment and environmental protection. Efficient heterogeneous catalysts are needed to completely oxidize azo-dyes under soft conditions. In this work, catalysts of Cu–Co oxide (1:2 molar ratio) supported on halloysite (Ha) nanotubes (CuCo(5 %)/Ha and CuCo(10 %)/Ha) were synthesized and used in the catalytic wet peroxide oxidation of reactive yellow 145 (RY-145) and basic red 46 (BR-46). The catalysts were characterized by chemical analysis, X-ray diffraction, Raman spectroscopy, N₂ adsorption isotherms, scanning electron microscopy and transmission electron microscopy. The results showed that the synthesized catalysts possess nanotubular structure with good mesoporosity, and the spinel structure CuCo₂O₄ was identified as the active phase deposited on Ha. The catalysts degraded these azo-dyes in diluted solutions (22 mg l⁻¹ of RY-145 and 35 mg l⁻¹ of BR-46) under mild reaction conditions (25^◦C, atmospheric pressure, pH 4 and minimum amounts of both catalyst and H₂O₂). Significant levels of dye conversion (93.1 ± 2.2 % for RY-145 and 54.4 ± 2.0 % for BR-46) were achieved in a relatively short time. In addition, significant values of total organic carbon removal (59.5 ± 1.8 % for RY-145 and 33.9 ± 1.4 % for BR-46) were obtained, indicating the total oxidation of a significant fraction of these dyes to CO₂ and H₂O.

9 illus, 3 tables, 51 ref

004002   SENGUPTA J, DAS K, NANDI U N, JACOB C (Electronic Science Dep, Jogesh Chandra Chaudhuri Coll, Kolkata - 700 033, Email: joydipdhruba@gmail.com) : Substrate free synthesis of graphene nanoflakes by atmospheric pressure chemical vapour deposition using Ni powder as a catalyst. Bull Mater Sci 2019, 42(4), 136.

Graphene nanoflakes (GNFs) were synthesized by atmospheric pressure chemical vapour deposition of propane (C₃H₈) employing Ni (salen) powder without the introduction of a substrate. The graphitic nature of the GNFs was examined by an X-ray diffraction method. Scanning electron microscopy results revealed that GNFs were stacked on top of one another and had a high aspect ratio. Transmission electron microscopy studies suggested that the GNFs were made up of a number of crystalline graphene layers, some of which were even single crystalline as evident from the selected area diffraction pattern. Finally, Raman spectroscopy confirmed the high quality of the GNFs.

5 illus, 31 ref

003997   SAGGAR S, UPADHAYAY A, GOSWAMI M (Pharmaceutical Sciences Dep, Mahatma Jyoti Rao Phoole Univ, Jaipur - 302 019, Email: sachinsaggar@yahoo.com) : Formulation and evaluation of solid self-emulsifying drug delivery system of bambuterol hydrochloride. Indian J Pharm Sci 2019, 81(4), 661-72.

The solid self-emulsifying drug delivery system of bambuterol hydrochloride was designed, prepared and evaluated to overcome poor bioavailability. The designing process included selection of oil phase, surfactant and co-solvent/co-surfactant based on saturated solubility studies. Psuedoternary phase diagram was constructed using dilution method to identify the self-emulsifying region. Liquid self-emulsifying drug delivery formulations were prepared from components obtained from these studies and were converted to solid self-emulsifying drug delivery systems by adsorption technique using microcrystalline cellulose:aerosil mixture as the adsorbent. The prepared solid self-emulsifying drug delivery system-based formulations were evaluated for drug content, morphology, globule size, micromeritic properties, ex vivo permeability and stability. Formulation F1 containing 10 mg bambuterol hydrochloride, triacetin (12.50 % w/w), Tween 80 (43.75 % w/w) and ethanol (43.75 % w/w) was concluded to be optimal. These results suggested that bambuterol hydrochloride can be formulated as a solid self-emulsifying drug delivery system, which could be used to improve oral bioavailability of bambuterol hydrochloride.

6 illus, 5 tables, 34 ref

003994   RIBEIRO S M, BOHRER D, LAPINSKI J, CARVALHO L N D, NASCIMENTO P T D, VIANA C (Chemistry Dep, UFSM, Santa Maria-RS, Brazil, Email: carineviana@yahoo.com.br) : Development and validation of an HPLC-dad method to quantify caffeine in time-release dosage forms. Indian J Pharm Sci 2019, 81(4), 626-32.

Controlled release caffeine dosage forms are applied in order improve bioavailability to enhance ergogenic and thermogenic actions. High-performance liquid chromatographic separation was achieved using a C18 reversed phase column, a binary mixture of 0.1 % phosphoric acid and acetonitrile with a flow rate of 0.8 ml/min. UV detection was at 220 nm. Water produced the best extraction efficiency in comparison with other solvents. Retention time observed for caffeine was 4.5 min. The method is selective, reliable, reproducible with a linear range over 1.0-20.0 µg/ml of caffeine (r>0.9987). The proposed method allows to distinguish caffeine from sibutramine, p-octopamine, p-synephrine, tyramine and hordenine. The limit of detection and limit of quantifications were 10 and 30 ng/ml, respectively. The proposed method could be used for the routine analysis of caffeine in time-release dietary supplements.

3 illus, 2 tables, 22 ref

002763   TUKIRAN, WARDANA A P, HIDAJATI N, SHIMIZU K (Chemistry Dep, Negeri Surabaya Univ, Surabaya, Indonesia, Email: tukiran@unesa.ac.id) : Chemical components and antioxidant activities of methanol extract of Syzygium polycephalum Miq. stem bark (Myrtaceae). Indian J Nat Prod Resour 2019, 10(2), 127-36.

This study aimed to reveal chemical components and screen antioxidant activity of methanolic extract of Syzygium polycephalum stem bark. The chemical components were isolated by using column chromatographic techniques and determined by spectroscopic methods (UV-Vis, FTIR, MS, and NMR) and comparison with literature data, in which the antioxidant activity was performed using 2,2’-diphenyl-1-picrylhydrazyl (DPPH). The present investigation resulted in four compounds involving gallic acid, pinostrobin, 3,4,3’-tri-O-methylellagic acid, and 3,3’-di-O-methylellagic acid. The four compounds were all in the form of phenolic compounds found from the extract whereas 3,4,3’-tri-O-methylellagic acid and 3,3’-di-O-methylellagic acid were ellagic acid derivatives. The methanolic extract, the four compounds, and vitamin C (as positive control) showed antioxidant activity against DPPH with the IC₅₀ value of 99.9; 10.0; 183.2; 72.1; 63.3; and 13.9 µg/mL, respectively. The antioxidant activity of gallic acid was more active than that of vitamin C. The present study confirms that Syzygium polycephalumis rich in phenolic compounds and natural antioxidants.

4 illus, 5 tables, 42 ref

002755   SUSHMITA T H, GUPTA M K, KUMAR C, KARTHIK S (Entomology Dep, Central Agricultural Univ, Imphal- 795 004, Manipur, Email: pipithockchom@gmail.com) : Toxicity of plant volatile oils against Callosobruchus maculatus. Indian J Entomol 2019, 81(2), 309-11.

Five plant volatile oils were evaluated against adults of Callosobruchus maculatus with fumigation and contact toxicity methods. Patchouli oil gave the lowest LC₅₀ value and thus the most toxic one, followed by cinnamon oil. The descending order of contact toxicity in LC₅₀ values was: patchouli oil (0.033 %) ˃ cinnamon oil (0.082 %) ˃ ginger oil (0.122 %) ˃ garlic oil (0.217 %) ˃ lemon oil (0.334%). The order of relative toxicity was as: patchouli oil (10.12) ˃ cinnamon oil (4.07) ˃ garlic oil (1.53) ˃ ginger oil (1.26) ˃ lemon oil (1.00) as revealed by the contact toxicity. As regards fumigant toxicity the order with LC₅₀ values was: cinnamon oil (0.060 %) ˃ ginger oil (0.243 %) ˃ lemon oil (1.442 %) ˃ patchouli oil (8.358 %) ˃ garlic oil (187.416 %). In terms of relative toxicity it was: cinnamon oil (3123.6) ˃ ginger oil (771.25) ˃ lemon oil (129.96) ˃ patchouli oil (22.42) ˃ garlic oil (1.00) with fumigation method.

1 table, 8 ref

002745   SENER T, BAYTAS A C (Aeronautics and Astronautics Dep, Istanbul Technical Univ, Istanbul, Turkey, Email: baytas@itu.edu.tr) : Experimental study of foam layout effects on NO emission inside a porous burner with three porous media layers. Indian J Chem Technol 2019, 26(3), 258-60.

The effect of foam layout on NO emission inside a a porous burner with three porous media layers has been experimentally studied. The experimental set-up included two zones, combustion and preheating. At the combustion zone, there are five layers of porous media with different pore densities; at the preheating zone, there are alumina spheres as porous media. Numerical solutions show that permutation of porous foams with different pore densities has an effect on emission rates. The purpose of this experimental study is to investigate effect of porous media permutation and equivalence on emission rates. Results indicate that when the foam density is decreased from combustion zone to exit, NO emission is declined.

1 illus, 2 tables, 5 ref

002691   BOUTEMAK K, CHEKNANE B, TAOUALIT N, AMMOUR H (Blida Univ, Blida- 09000, Algerie, Email: kboutemak@yahoo.fr) : Sorption of malachite green and Rhodamine-B dyes from aqueous solution by biomass waste: Kinetics, isotherm and thermodynamic studies. Indian J Chem Technol 2019, 26(3), 252-7.

A biomass waste has been evaluated without chemical modification as low-cost effective adsorbent to remove Malachite Green (MG) and Rhodamine-B (RhB) dye srespectively from aqueous solution in batch experiment. The effect of certain parameters on the adsorption capacity has been investigated such as particle size, contact time, initial dye concentration, pH, mass of the adsorbent and the effect of temperature. Isotherms study has been described by the Freundlich model which indicates that MG and Rh-B sorption process onto biomass is more described by good correlation coefficients (R²=0.867 and 0.953, respectively). Kinetic study shows that MG and Rh-B adsorption process follow pseudo-second order kinetics model. Furthermore, thermodynamic parameters reveal that the adsorption is spontaneous and endothermic.

5 illus, 4 tables, 25 ref