Spatial Structure of the Acth-(6-9)-PGP Molecule

The spatial structure of ACTH-(6-9)-PGP molecule has been investigated using theoretical conformational analysis method. Amino acid sequence of the N-terminal pentapeptide fragment of His-Phe-Arg-Trp-Pro of this molecule conforms to the fragment 6-9 of ACTH hormone. Calculations of conformational states of this molecule are carried out regarding nonvalent, electrostatic and torsional interactions and the energy of hydrogen bonds. The spatial structure of the His-Phe-Arg-Trp-Pro-Gly-Pro molecule was estimated on the low–energy conformations of the N-terminal tetrapeptide fragment His-Phe-Arg-Trp and C-terminal tripeptide fragment Pro-Gly-Pro of this molecule. It is shown that the spatial structure of heptapeptide molecule can be presented by 11 low-energy forms of the main chain. The low–energy conformations of this molecule, the values of dihedral angles of the backbone and side chains of the amino acid residues were founded and the energies of intra- and inter-residual interactions were determined.read more


Namiq Akhmedov, Leyla Agayeva, Gulnara Akverdieva, Rena Abbasli and Larisa Ismailova

Preparation of Poly(aniline-co-phenol) and Study Its Properties and Its Polymerization Kinetics Using Two Methods: UV-Vis and HPLC

The co-polymerization of polyaniline is one of the most important methods used to improve the electrical activity and thermal stability of polyaniline. Previously, electrochemical co-polymerization of phenol and aniline was performed on 304 stainless steel anodes. In this study, we present the co-polymerization of aniline and phenol chemically at laboratory temperature in an acidic medium with ammonium pyrosulfate as an oxidant. The Scanning Electron Microscopy (SEM) analysis of poly(aniline-co-phenol) sample shows a rough (non-smooth) surface with crystalline particles with microscopic diameters. We characterized the prepared polymer with DSC, DTA, and thermos gravimetric analysis (TGA). We found that the thermal decomposition of poly(aniline-co-phenol) was on six steps. The glass transition temperature of the co-polymer (Tg) was found at 863.89 °C and the melting transition temperature was observed at 877.80 °C. We studied the kinetics of Poly(aniline-co-phenol) using two methods: UV-Vis, HPLC. Then we determined the reaction order. It was found that the reaction was the zero-order reaction (n=0) in both previous two methods.read more


Juhaina Alghdir and Ahmad Falah

Comparative Biocompatibilities of Various Sizes of AgCIT and AgPVP with their Protein Coronas Nanoparticles

Biocompatibilities of nanoparticles are crucial for biomedical applications. Diverse silver nanoparticles (5 nm, 10 nm, 20 nm, 40 nm and 80 nm) caped with citrate and polyvinylpyrrolidone (PVP) were synthesized and primed their protein coronas. Nanoparticles were characterized with UV-visible spectroscope, Dynamic light scattering (DLS) and Transmission Electron Microscope (TEM). Comparative biocompatibilities were verified and recorded using MTS techniques. Human hepatoma carcinoma HepG2) cell line was used for measuring cytotoxic effect by MTS assays. Deleterious and comparative behaviors of citrate and PVP supported nanoparticles with varied dimensions were investigated and concluded; that citrate caped nanoparticles are comparatively less toxic and independent of size than PVP supported nanoparticles, having increased cytotoxicity with increasing size. The cytotoxic effect of citrate caped and its protein coronas nanoparticles was insignificant, while the boosted concentration of PVP supported nanoparticles enhanced the toxic effect, which endorsed enlarged size and amount of PVP supported nanoparticles. As medicinal precursors, the overwhelming use of PVP nanoparticles should be avoided, and a unique protocol must be designed if its use is crucial and unavoidable.read more


Abdul Hameed, Komal Saba, Raheela Taj, Andaleeb Azam, Rohullah and Aamina Paracha

Effect of Salt on the Stability of Vegetable Oil-in-Water Emulsions Stabilized by Soybean Protein and Microgel

The preparation of vegetable oil-water emulsions stabilized by soybean protein and microgel is described. The soybean protein was obtained from n-hexane-defatted soybean powder using a Soxhlet extractor. Using equal volumes of oil and water, vegetable oil-water emulsions were formed either by handshaking the mixture or homogenizing the mixture using a Lab homogenizer. The emulsion was characterized using a drop test and microscopy observation. The drop test shows that the preferred emulsion is vegetable oil-in-water (o/w). The effect of salt and emulsifier concentration on the stability and emulsion drop size was investigated. Emulsions stabilized by soybean protein without addition of salt breakdown after 3 days of preparation because of decomposition of the protein. For emulsions stabilized by microgel in the absence of salt, phase separation occurred within 1 hour. At a fixed salt concentration, it was found that increasing the emulsifier concentration has a significant effect on the stability and drop size of the emulsions stabilized by both protein and microgel. For emulsions stabilized by soybean protein, the stability of emulsions increased with increasing salt concentration without any significant influence on the drop size. The results obtained from the surface tension measurement revealed that different mechanisms of stabilization exist in emulsions stabilized by the protein and microgel.read more


Samuel Olalekan Olusanya, Gbenga Joseph Adebayo, Samuel Olutayo. Afolabi and Adewumi Oluwasogo Dada

Adsorption of the Orange Methyl Dye and Lead (II) by the Cationic Resin Amberlite®IRC-50: Kinetic Study and Modeling of Experimental Data

During this present study, we tested the adsorption performance of heavy metal ions; bivalent lead (Pb (II)) and the anionic dye (methyl orange (MO)) from model aqueous solutions with the ion exchange resin of the Amberlite®IRC-50 type. This performance was evaluated using inductively coupled plasma (ICP) and atomic absorption spectroscopy (AAS). The pH of the solution was adjusted to 6.5 for the bath temperature, the initial mass concentration of Pb (II) and MO was adopted at 20 mg/L, the mass of the resin-type adsorbent Amberlite®IRC-50 was taken at 0.1g and the adsorption capacity Qe was studied. The results obtained during this study show that the kinetic study of the adsorption was obtained at the contact time t = 30 min for the metal Pb (II) and at t = 60 min for the dye MO. These results also showed that the equilibrium of adsorption was reached at time t = 60 min with an adsorption performance of around 99% for Pb (II) and around 96% for MO. Note that the parameters of different mathematical models indicate that the adsorption process is spontaneous in the second degree.read more


Jaouad Bensalah, Mohamed Berradi, Amar Habsaoui, Omar Dagdag, Adblhay El Amri, Omar El Khattabi, Ahmed Lebkiri and El Housseine Rifi

Application of Collagen Hydrolysate Extracted from Limed Hide Waste in the Crop Grow Seedlings

In this work, the collagen hydrolysates with different molecular weights were successfully extracted from the limed hide waste, and used at the nutrient solutions for crop breeding. Firstly, using the single factor and orthogonal exp eriments, hydrolytic process parameters of limed hide waste were optimized for the Alcalase-based enzymatic and Ca(OH)2-based alkali, and alkali-enzyme methods that led to the corresponding collagen hydrolysates with different molecular weights. The obtained collagen hydrolysates were characterized by gel permeation chromatography (GPC), amino acid analysis, the inductively coupled plasma optical emission spectrometer (ICP-OES), and Kjeldahl method. Then, the collagen hydrolysates were used as organic nitrogen sources to prepare fertilizers for the grow seedlings of Triticum aestivum, Glycine max, and Brassica napus, and inorganic nitrogen solutions were used as controls. The effects of these nutrient solutions on the seedlings and growth of the three crops were investigated. Concretely, the germination rate, plant weight, seeding height, soluble sugar content, and chlorophyll content were tested. Results indicated that all the collagen hydrolysate products could be used to prepare water-soluble fertilizers that can intensively boost germination, plant weight, and seeding height, and greatly increase soluble sugar and chlorophyll content in leaves. Furthermore, the fertilizer efficiencies of all the tested degradation products are much better than that of the water-soluble fertilizer containing inorganic nitrogen. All the proteolytic nutrient solutions with different molecular weights can promote the growth of crops, but the smaller the molecular weight is, the better the growth effect of crops is, which is manifested in the higher germination rate, plant weight, seedling height, soluble sugar content and chlorophyll content of seeds.read more


Li Zhao, Yanru Long and Haibin Gu

Kinetics of Electron Transfer Reaction between Co(II) and Chlorate Ions: Experimental and Modeling Study

This research article reports original experimental and modeling detail of kinetics of the electron transfer reaction between Co(II) and chlorate ions in acetic acid solution. Design of experiment methodology has been employed to elucidate the effects of temperature and initial concentrations of reactants on the rate of reaction. Levenberg-Marquardt method has been used to fit processed kinetic data (temperatures, initial concentrations of reactants, and concentrations and rates of production of Co(III)) on to various possible rate equations. This algorithm provides a proficient mean for compensating the capricious effects of the experimental process variables and results in the maximum likelihood estimates of the kinetic parameters. The most significant rate law has been selected, on the basis of statistical analyses of the residuals between the predicted and experimental rates. The analyses suggest that the intrinsic rate of reaction is proportional to first power of chlorate concentration but for Co(II) the order is fractional (0.7455 ≈ ¾). The effect of temperature on the observed rate constant (precision = 0.02 %) is excellently described by the Arrhenius and Eyring equations and the sluggish nature of the reaction is clearly manifested by the high energy (> 93 kJ/mol), negative entropy (-28.5286 J/mol-K) and very small equilibrium constant of activation. Further fairly negative standard entropy of activation shows there is usually considerable rearrangement of energy among various degrees of freedom during the formation of activated complex and proposes an associative mechanism for formation of the activated complex. This research is performed to develop a kinetic model for the electron transfer reaction between Co(II) and chlorate ion. As a result, a redox couple of Co(II)/Co(III) has been formed which is used as a potent oxidation catalyst in chemical industries.read more


Mahwish Mobeen Khan and Syed Mumtaz Danish Naqvi

Synthesis of New Series of Phenyldiazene Based Metal Complexes for Designing Most Active Antibacterial and Antifungal Agents

In this study, In Vitro antibacterial and antifungal activities of azo series based on transition metal complexes (Cu2+, Zn2+, Mn2+, Co2+ and Ni2+) with already our reported ligands named as; [(E)-1-(1, 3-dioxolan-2-yl)-2-phenyldiazene] (K-1), [(E)-1-(1, 3-dioxolan-2-yl)-2-(4-methylphenyl)diazene] (K-2), 2-[(E)-phenyl diazenyl]-1H-benzimidazole] (K-3), [(E)-1-(1, 3-dioxolan-2-yl)-2-(4-ethylphenyl)diazene] (K-4), and [(E)-1-(1, 3-dioxolan-2-yl)-2-(2-methylphenyl)-diazene] (K-5) were studied. FTIR 1H-NMR and mass spectrometric techniques were applied for interpretation of synthesized complexes. 4.05-4.07 ppm chemical shift appearance of azo group confirms azo coupling with transition metal complexes. N=N, C-H, C-N and C-O groups are also confirmed by FTIR which exhibited peaks at 1400-1500, 2090-3090, 1100-1180, 1010-1060 and 625-780 cm-1. Furthermore, mass spectroscopic data also gives strong indication for the synthesis of metal complexes. All the newly synthesized complexes were screened for their antibacterial and antifungal activities. Antibacterial and antifungal activity against S. aureus, E.coli and A.niger, A.ustus and C.albican at conc. 250 µg/ml showed excellent activity by K-1 complexes (Co2+, Cu2+, Ni2+), K-5 complexes (Zn2+, Mn2+, Cu2+), K-2 complexes (Co2+, Cu2+, Mn2+) and K-3 (Zn2+, Mn2+, Co2+, Cu2+) as compared to standard drug (Ampicillin). Hence, based on this study, it was concluded that these azo based complexes may act as a platform for designing more active antibacterial and antifungal agents.read more


Khalil Ahmad, Habib-ur-Rehman Shah, Areeba Ashfaq, Muhammad Ashfaq, Muhammad Kashif, Hafiza Ammara Naseem, Tariq Aziz, Sajidah Parveen and Hafsa and Imran Nazir

Preparation, Preliminary Characterization and Antiangiogenic Activities of Polysaccharides from Pomegranate Peels

In the present study, the crude polysaccharides from pomegranate peels (CPP) were prepared by compound enzyme-extraction technology, and the response surface methodology was used to optimize the extraction parameters. Box–Behnken design (BBD) was applied to estimate the effects of extraction temperature, extraction pH, and dosage of compound enzyme on the yield of CPP. A mathematical model with high fitness was obtained. Extraction temperature, extraction pH, and dosage of compound enzyme exhibited independent and interactive effects on CPP yield. CPP were purified by macroporous resin HP-20 and Sephadex G-100 column chromatography to afford purified fraction of CPP-2. The relative molecular weight of CPP-2 was 93.5 kDa. In CPP-2, and FT-IR spectra showed that the main components among CPP-2 may be pectic polysaccharides.The effect of CPP-2 on angiogenesis was measured in vivo by using the chick embryo chorioallantoic membrane (CAM) assay. The results demonstrated that CPP-2 suppressed angiogenesis in chicken embryos.read more


Chunlin Ke and Zuomei Li

Design, Synthesis and Antioxidant Activity of Chalcone Derivative CMZ-3-5

Excessive accumulation of free radicals can cause a variety of diseases. According to reports, chalcone has the activity of scavenging free radicals. In this study, we synthesized a chalcone derivative CZM-3-5 and evaluated its antioxidant activity using a chemical assessment method (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+) assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH•) assay and total reducing antioxidant power (FRAP) assay) and a cell model of oxidative damage induced by hydrogen peroxide (H2O2). The chemical evaluation results show that the compound CZM-3-5 has good antioxidant capacity and free radical scavenging ability. MTT analysis showed that the compound has cytoprotective activity in H2O2-induced PC12 cells, and the mechanism may be related to the cytoprotective substance superoxide dismutase (SOD) is related to the level of glutathione (GSH). Overall, our findings indicate that compound CZM-3-5 has potential antioxidant activity in vitro.read more


Cen Xiang, Xiangshun Kong, Feng Gao, Yufan Zhao, Jiang Liu, Yuan Yuan and Yuou Teng

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