Novel Synthesis Method, Characterization and Bioactivities of a Copper(Ⅱ)-Hesperetin Complex Using Ion Exchange Column

2020 ◽  
Vol 42 (2) ◽  
pp. 204-204
Author(s):  
Huan Wang Huan Wang ◽  
Boru Chen and Siming Zhu Boru Chen and Siming Zhu

A copper(Ⅱ)-hesperetin complex formulated as [Cu(L)2(H2O)2]and#183;H2O (andquot;Landquot; represented the ligand hesperetin) was synthesized using a novel ion-exchanging resin column method, based on the integration of the separation of hesperetin on hesperetin-loaded resins and the reaction of hesperetin with Cu2+ using CuCl2 as an eluent and reacting reagent. The feasibility of this new method was testified firstly. Results indicated the D296 macroporous strong basic anion exchange resin could effectively adsorb hesperetin and the saturated adsorption capacity was 143.5 mg per mL resin. The favorable concentration of CuCl2 was 0.4 mol/L for the elution and the coordination process of hesperetin. The characterization of the copper(Ⅱ) complex was done by theoretical quantum chemical calculation, elemental and thermal analyses, UV-Vis absorption spectra, FTIR spectra and XRD analysis, results testified that the 4-carbonyl group and 5-hydroxyl group of hesperetin were involved in the coordination reaction. The comparison between hesperetin and its copper(Ⅱ) complex about their bioactivities like the inhibitory effect of α-amylase, antioxidant activities and solubility were evaluated. Results showed the bioactivities of the copper(Ⅱ) complex was better than that of hesperetin.

2018 ◽  
Vol 69 (1) ◽  
pp. 38-44
Author(s):  
Nicoleta Mirela Marin ◽  
Olga Tiron ◽  
Luoana Florentina Pascu ◽  
Mihaela Costache ◽  
Mihai Nita Lazar ◽  
...  

This study investigates the synergistic effects of ion exchange and biodegradation methods to remove the Acid Blue 193 also called Gryfalan Navy Blue RL (GNB) dye from wastewater. Ion exchange studies were performed using a strongly basic anion exchange resin Amberlite IRA 400. The equilibrium was characterized by a kinetic and thermodynamic points of view, establishing that the sorption of the GNB dye was subject to the Freundlich isotherm model with R2 = 0.8710. Experimental results showed that the activated resin can removed up to 93.4% when the concentration of dye solution is 5.62�10-2 mM. The biodegradation of the GNB was induced by laccase, an enzyme isolated from white-rot fungus. It was also analyzed the role of pH and dye concentration on GNB biodegradation, so 5�10-2 mM dye had a maximum discoloration efficiency of 82.9% at pH of 4. The laccase showed a very fast and robust activity reaching in a few minutes a Km value of 2.2�10-1mM. In addition, increasing the GNB concentration up to 8�10-1 mM did not triggered a substrat inhibition effect on the laccase activity. Overall, in this study we proposed a mixt physicochemical and biological approach to enhance the GNB removal and biodegradability from the wastewaters and subsequently the environment.


1995 ◽  
Vol 60 (9) ◽  
pp. 1429-1434
Author(s):  
Martin Breza

Using semiempirical CNDO-UHF method the adiabatic potential surface of 2[Cu(OH)6]4- complexes is investigated. The values of vibration and vibronic constants for Eg - (a1g + eg) vibronic interaction attain extremal values for the optimal O-H distance. The Jahn-Teller distortion decreases with increasing O-H distance. The discrepancy between experimentally observed elongated bipyramid of [Cu(OH)6]4- in Ba2[Cu(OH)6] and the compressed one obtained by quantum-chemical calculation is explainable by hydrogen bonding of the axial hydroxyl group.


Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1554
Author(s):  
Justinas Januskevicius ◽  
Zivile Stankeviciute ◽  
Dalis Baltrunas ◽  
Kęstutis Mažeika ◽  
Aldona Beganskiene ◽  
...  

In this study, an aqueous sol-gel synthesis method and subsequent dip-coating technique were applied for the preparation of yttrium iron garnet (YIG), yttrium iron perovskite (YIP), and terbium iron perovskite (TIP) bulk and thin films. The monophasic highly crystalline different iron ferrite powders have been synthesized using this simple aqueous sol-gel process displaying the suitability of the method. In the next step, the same sol-gel solution was used for the fabrication of coatings on monocrystalline silicon (100) using a dip-coating procedure. This resulted, likely due to substrate surface influence, in all coatings having mixed phases of both garnet and perovskite. Thermogravimetric (TG) analysis of the precursor gels was carried out. All the samples were investigated by X-ray powder diffraction (XRD) analysis. The coatings were also investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM) and Mössbauer spectroscopy. Magnetic measurements were also carried out.


e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 154-161 ◽  
Author(s):  
Gao Yurong ◽  
Li Dapeng

AbstractCorn starch/polyvinyl alcohol (PVA)/glycerol composite films incorporated with ε-polylysine were prepared, and their properties were investigated. The Fourier-transform infrared (FTIR) spectroscopy indicated that the interactions happened between the amino group of ε-polylysine and hydroxyl group starch/PVA composite films. X-ray diffraction (XRD) analysis showed that the addition of ε-polylysine decreased the intensity of all crystal peaks. Thermogravimetric (TGA) analysis suggested that ε-polylysine improved the thermal stability of composite films. Scanning electron microscopic (SEM) analysis showed that the upper surface of composite films incorporated with ε-polylysine presented more compact and flat surface. The antimicrobial activity of the composite film progressively increased with the increasing of ε-polylysine concentration (P < 0.05). The tensile strength, elongation at break and water absorption significantly increased, whereas water solubility decreased with the increasing of ε-polylysine concentration (P < 0.05). Therefore, the corn starch/PVA/glycerol composite films incorporated with ε-polylysine had good mechanical, physical and antimicrobial properties and could have potential application as a novel antimicrobial packaging material.


2002 ◽  
Vol 35 (1) ◽  
pp. 32-39 ◽  
Author(s):  
Hiroyuki Yoshida ◽  
Steffen Oehlenschlaeger ◽  
Yuji Minami ◽  
Masaaki Terashima

Author(s):  
Ganiyu Oboh ◽  
Veronica O. Odubanjo ◽  
Fatai Bello ◽  
Ayokunle O. Ademosun ◽  
Sunday I. Oyeleye ◽  
...  

AbstractAvocado pear (The inhibitory effects of extracts on AChE and BChE activities and antioxidant potentials (inhibition of FeThe extracts inhibited AChE and BChE activities and prooxidant-induced TBARS production in a dose-dependent manner, with the seed extract having the highest inhibitory effect and the leaf extract exhibiting higher phenolic content and radical scavenging abilities, but lower Fe chelation ability compared with that of the seed. The phytochemical screening revealed the presence of saponins, alkaloids, and terpenoids in both extracts, whereas the total alkaloid profile was higher in the seed extract than in the leaf extract, as revealed by GC-FID.The anti-cholinesterase and antioxidant activities of avocado leaf and seed could be linked to their phytoconstituents and might be the possible mechanisms underlying their use as a cheap and natural treatment/management of AD. However, these extracts should be further investigated in vivo.


2018 ◽  
Vol 7 (2) ◽  
pp. 74-83
Author(s):  
Cherifa Zahaf ◽  
Djilali Achour ◽  
Meriem Mokhtar ◽  
Moussa Brada

The aim of the current study was to identify the essential oils of Juniperus oxycedrus from North Western Algeria (Mostaganem) by gas chromatography coupled to mass spectrometer (GC-MS), and to evaluate their antibac-terial and antioxidant activities. Extraction was carried out by two processes, hydrodistillation (HD) and steam distillation (SD). Analysis by GC-MS led to the identification of 38 components using both methods. HD was found to be the best process for the extraction of Juniperus essential oil, and the ma-jor identified compounds were: germacrene-D (38.28%), followed by α.-pinene (17.66%), and δ-cadinene (5.91%). In the antibacterial test, SD oil had a higher inhibitory effect. The strain Staphylococcus aureus was the most sensitive with an inhibition zone of 15.25 mm and a minimum inhibitory concentration (MIC) of 0.25 mg/mL. The antioxidant activity of J. oxycedrus es-sential oils obtained by HD was more important than SD (IC50= 19.52 mg/mL and IC50= 38.62 mg/mL) with DPPH and β-carotene bleaching tests respec-tively. Essential oils of J. oxycedrus could therefore represent good candidates to be used as antioxidant and antibacterial agents.


2021 ◽  
Vol 16 (8) ◽  
pp. 38-49
Author(s):  
Siva Kumar Kandula ◽  
Satyanarayana Swamy Cheekatla ◽  
Venkata Satya Mahesh Kumar Metta ◽  
Venkata Rajagopal Saladi

Natural antioxidants, in particular phenolic derivatives, are used efficiently to combat against oxidative induced tissue damages. The objective of the study is to determine the antioxidant potential of methanolic extracts obtained from eight marine algal species (Enteromorpha compressa, Chaetomorpha antennina, Caulerpa racemosa, Caulerpa taxifolia, Sargassum vulgare, Padina tetrastromatica, Amphiroa fragilissima and Gracilaria corticata) by assessing their total phenolic content, DPPH scavenging assay, FRAP assay, H2O2 radical and superoxide radical scavenging activities. Among them, P.tetrastromatica, S.vulgare, E.compressa, C.taxifolia display significant antioxidant activities. Further, the aqueous extracts of these four algae are used for bioreduction of silver nitrate to silver nanoparticles (AgNPs) by green synthesis method at room temperature. UV-Visible spectrum revealed the surface plasmon resonance at 430 and 440nm. The characterizations of AgNPs by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) studies revealed the bioreduction and capping of AgNPs. XRD analysis elucidated the synthesized nanoparticles having face centered cubic crystalline geometry, with a mean size of 17 nm. The nanoparticles have better antimicrobial activity against cocci shaped than the rod shaped bacteria. The minimum inhibitory concentration and minimum bactericidal concentration exhibit more activity against S.aureus and B.cereus rather than E.coli.


2020 ◽  
Vol 42 (1) ◽  
pp. 109-109
Author(s):  
Hao Zang Hao Zang ◽  
Qian Xu Qian Xu ◽  
Luyun Zhang Luyun Zhang ◽  
Guangqing Xia Guangqing Xia ◽  
Jiaming Sun and Junyi Zhu Jiaming Sun and Junyi Zhu

A series of hydroxytyrosol (HT) derivatives were synthesized by modification of alcohol hydroxyl group of HT, twenty-five target compounds were obtained and characterized by NMR and HRMS. The antioxidant activities of those compounds were evaluated in three different assays. Except 3e and 3y, all other compounds demonstrated significant 2,2and#39;-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) free radical cation scavenging activity ranging from IC50 3.4 to 24.4 μM, which were more potent than L-ascorbic acid (IC50=24.8 μM). Compounds 3b-3d, 3f-3k, 3m-3x were better than Trolox (18.3 M). Moreover, the ferric reducing antioxidant power (FRAP) of all compounds were discovered to be more potent than L-ascorbic acid (40.7 mmol/g), except 3e, all other compounds (141.5-202.1 mmol/g) were better than Trolox (94.7 mmol/g). Compounds 3a-3d, 3f-3j, 3l-3m, 3o, 3q, 3t, 3v-3y exhibited more potent hydroxyl radical scavenging activity (IC50=245.1-475.1 M) than L-ascorbic acid (554.4 M) and Trolox (500.4 M). Compounds 3q, 3t and 3y exhibited more potent -Glucosidase inhibition activity (39.1-52.4 M) than Acarbose (60.9 M). Compounds 3a, 3d, 3f-3m, 3s-3t, 3v-3y showed some acetylcholinesterase inhibition activities, compounds 3a, 3d, 3f-3j, 3l-3m, 3o-3p, 3s-3t, 3w showed some butyrylcholinesterase inhibition activities.


2011 ◽  
Vol 186 ◽  
pp. 7-10 ◽  
Author(s):  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Bao Sen Wang ◽  
Ying He

Single phase Al3+ doped LiMn2O4 has been prepared by flameless solution combustion synthesis method at 600oC for 1h. X-ray diffraction (XRD) and scanning electric microscope (SEM) were used to determine the phase composition and micro morphology of the products. XRD analysis indicates that the purities increase and the lattice parameters of the products decrease with increasing Al3+ content. Electrochemical test indicates that the cycling performance of the products with Al3+ doping are better than that of the product without Al3+ doping. The product LiAl0.10Mn1.90O4 gets the best electrochemical performance. At the current density of 30mA/g, the initial discharge capacity of LiAl0.10Mn1.90O4 is 124.8mAh/g, and after 20 cycles, the capacity retention is more than 89%. SEM investigation indicates that the particles of LiAl0.10Mn1.90O4 are sub-micron in size and well dispersed.


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