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Habibat F. Chahul, David T. Orhemba and Taiwo A. Gbadamosi

the inhibiting action of Aspilia africana extract on corrosion of aluminium alloy AA3003 in hydrochloric acid, Journal of Material Science 47 (2012) 2559 - 2572. [9]. H.F. Chahul, A.M. Ayuba, S. Nyior, Adsorptive, kinetic, thermodynamic and inhibitive properties of Cissus populnea stem extraction the corrosion of aluminium in HCl, ChemSearch Journal 1 (2015) 20 - 30. [10]. E.E. Oguzie, C.K. Enenebeaku, C.O. Akalezi, S.C. Okoro, A.A. Ayuk, E.N. Ejike, Adsorption and corrosion inhibiting effect of Dacryodis edulis extract on low carbon steel

Open access

Simona Dobrinas, Alina Soceanu, Gabriela Stanciu, Viorica Popescu and Luiza Georgiana Arnold

Abstract

The aim of this study was to determine Cu, Fe and Cr contents of three species of fresh mushrooms and canned mushrooms: white and brown champignon (Agaricus bisporus) and Pleurotus Ostreatus. Were analyzed various plant parts: stem, cap and cuticle of fresh mushrooms and only stem and cap for canned mushrooms. The levels of trace metals of mushroom samples collected from regions of Romania, Poland and Turkey were determined by UV/Visible spectrometry - standard addition method after digestion method. The contents of investigated trace metals in mushroom samples were found to be in the range of 0.01 - 2.26 mg/Kg for chromium, 2.02 - 430.67 mg/Kg for copper and 240.40 - 7952.89 mg/Kg for iron. The iron content was found to be higher than those of the other two minerals in all the samples. Mushrooms species in the highest levels of trace elements were found white champignon for Cu and Fe and brown champignon for Cr.

Open access

Faith Iguodala Akinnibosun and Bolorunduro Lanre Adewumi

Abstract

This study is aimed at evaluating the qualitative and quantitative phytochemical composition of various parts (leaf, stem bark, root, seed and pulp) of Cola millenii a medicinal plant of southwestern Nigeria. The bioactive ingredients were extracted using water, ethanol and n-hexane in a solvent-percolation protocol. The qualitative phytochemical screening result revealed the presence of alkaloids, saponins and tannins in all the parts of the plant analyzed. Glycosides was found in only the seed and pulp extracts while only the seed, leaf and stem bark contain terpenoids. Also, flavonoids were found in pulp extract only whereas, anthraquinones were not found in all the plant parts. In the quantitative analyses aqueous extracts of the pulp parts contained higher saponins (1.81%), tannins (0.77%) and flavonoids (1.12%) followed by seed aqueous extract which had 0.62%, 0.51%, 0.70% and 0.47% composition of alkaloids, saponins, glycosides and terpenoids respectively. In ethanol extract, pulp extract also had higher percentage of alkaloids (1.72%), saponins (2.24%), tannins (1.15%) and flavonoids (1.21%) compared to other parts of the plant however, glycosides was found in higher percentage in seed extracts (1.10 %) than in pulp (0.21%). Moreover, in n-hexane extracts of the plant parts, pulp extracts revealed higher percentage of alkaloids (1.71%), saponins (1.40%) and flavonoids (0.93%) followed by stem bark extract whereas glycosides was present in higher percentage in seed (0.82%) than pulp extracts (0.38%). In all, the pulp and seed extracts of the plant contained more phytochemicals than other parts screened. Moreover, pulp extracts contain higher percentage of these phytochemicals than the other parts except glycosides and terpenoids which were more abundant in seed extracts than the other parts. Among different solvents used for extraction in the series, ethanol had the highest extraction capacity in pulp, leaf and stem bark extracts while n-hexane had the best extraction capacity in the seed extract. Thus, C. millenii may possess medicinal properties which may be expeditiously utilized in the pharmaceutical industry.

Open access

L. Kępiński

Transmission Electron Microscopy as indispensable tool for imaging and chemical characterization of heterogeneous catalysts

Transmission Electron Microscopy (TEM) and its mutation Scanning Transmission Electron Microscopy (STEM) is one of the most important methods providing unique information on structure and chemistry of solid catalysts at length scale down to level. The principal reason is its high spatial resolution (below 0.1 nm) but also universality, i.e., ability of observation of both images and diffraction patterns of individual nanometer size objects. Recent advances in TEM in particular application of image and beam correctors, possibility of studying specimens at non vacuum conditions (environmental TEM) and possibility of dynamic (time resolved) studies even further broadened the applicability of the method in catalysis.

Open access

Lenka Rottmannová, Peter Škorňa, Ján Rimarčík, Vladimír Lukeš and Erik Klein

Abstract

In spite of the importance of proton transfer in solution-phase processes, there is still no systematic theoretical study of proton solvation enthalpies. We have investigated the solvation enthalpies of the proton in seven solvents of various polarities (benzene, chloroform, acetone, methanol, ethanol, DMSO, water) using the Integral Equation Formalism Polarized Continuum Model (IEF-PCM). All computations were performed at the B3LYP and BHLYP levels of theory with aug-cc-pVDZ, aug-cc-pVTZ and aug-cc-pVQZ basis sets. Our calculations have shown that the B3LYP and BHLYP functionals provide similar solvation enthalpies. Finally, differences in the solvation enthalpy of the proton values stemming from the various basis sets do not exceed 6 kJ mol-1, with exception of DMSO and chloroform. Distance between H+ and the acceptor atom of the solvent molecule is the shortest in the case of water. It has been also found that the B3LYP distances are slightly longer.

Open access

Dilek Bilgic Alkaya, Serap Ayaz Seyhan and Busra Nagihan Ozturk

References [1]. M. Ozturk, F.A. Ozturk, M.E. Duru, G. Topçu, Antioxidant activity of stem and root extracts of Rhubarb ( Rheum ribes ): An edible medicinal plant, Food Chemistry 103 (2007) 623-630. [2]. B.E. Abu-Irmaileh, F.U. Afifi, Herbal medicine in Jordan with special emphasis on commonly used herbs, Journal of Ethnopharmacology 89 (2003) 193–197. [3]. M. Zahedi, M.R. Hojjati, H. Fathpour, Z. Rabiei, Z. Alibabaei, A. Basim, Effect of Rheum ribes hydro-alcoholic extract on memory impairments in rat model of Alzheimer's disease, Iranian

Open access

Nkoli Marynnn Mgbemena, Ifenna Ilechukwu, Felicia Uchechukwu Okwunodolu, Joe-Vera Ogugua Chukwurah and Isioma Blessing Lucky

induced diabetic rats, Biosciences Research Support Foundation 1 (2015) 84–89. [7]. C.O. Okolo, Analgesic effect of Irvingia gabonensis stem bark extract, Journal of Ethno pharmacology 45 (1995) 125–129. [8]. H.C. Okolo, Industrial potential of various Irvingia gabonensis products such as oil, ogbono and juice, ICRAF-IITA Conference on Irvingia gabonensis , Ibadan, Nigeria (1994). [9]. O.O. Ekpe, I.B. Umoh, O.U. Eka, Effect of a typical and processing method on the proximate composition and amino acid profile of bush mango seeds ( Irvingia

Open access

Svetlana Kryštofová

, Lundgren M (2015) Biochimie 117:119—128. Reyon D, Tsai SQ, Khayter C, Foden JA, Sander JD, Joung JK (2012) Nat. Biotechnol 30: 460—465. Richter C, Chang JT, Fineran PC (2012) Viruses 4: 2291—2311. Shalem O, Sanjana NE, Hartenian E, Shi X, Scott DA, Mikkelsen TS, Heckl D, Ebert BL, Root DE, Doench JG, Zhang F (2014) Science 343: 84—87. Schwank G, Koo B-K, Sasselli V, Dekkers JF, Heo I, Demircan T, Sasaki N, Boymans S, Cuppen E, van der Ent CK, Nieuwenhuis EES, Beekman JM, Clevers H (2013) Cell Stem Cell 13: 653—658. Spilman M, Cocozaki A