Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 332

Search results for: mukaadial acetate

332 Antiplasmodial Activity of Drimane Sesquiterpene Isolated from Warburgia salutaris

Authors: Mthokozisi Simelane

Abstract:

Background: Malaria remains a life-threatening disease in tropical regions despite the advances in the treatment of this disease, it still remains a significant burden as some parasites have become resistant to the currently available drugs. This has created a necessity for the development of alternative, more efficient antimalarial drugs. Warburgia salutaris is a traditional medicinal plant used in malaria treatment by Zulu traditional healers. Materials and methods: The W. salutaris stem-bark was extracted with dichloromethane and the compound was isolated through column chromatography. The compound was identified and characterized by spectroscopic analysis (1H NMR, 13C NMR, IR and MS) and the structure was also confirmed by x-ray crystallography. The anti-plasmodial activity (in vitro) was studied on NF54 Plasmodium falciparum strain (CQS). Cytotoxicity was measured using the MTT assay on HEK239 and HEPG2 cell lines. Docking of Mukaadial acetate was conducted in AutoDock Vina. Structural modifications were conducted in UCSF Chimera and molecular interactions examined in LigPlot. Results: The compound, Mukaadial Acetate showed appreciable inhibition (IC50 0.44±0.10 µg/ml) of the parasite growth and cytotoxicity activity of 0.124±0.109 and 0.199±0.083 (µg/ml) on HEK293 and HEPG2 cells respectively. Molecular docking revealed that Mukaadial Acetate binds to the purine, pyrophosphate and ribose binding sites of the PfHGXPRT with an optimum binding conformation and forms hydrogen bond, steric and hydrophobic interactions with the residues inhabiting the respective binding sites. Conclusion: It is apparent that W. salutaris contains components (including Mukaadial Acetate) that exhibit antimalarial activity. This study scientifically validates the use of this plant in folk medicine.

Keywords: plasmodium falciparum, molecular docking, antimalarial activity, PfHGXPRT, Warburgia salutaris, mukaadial acetate

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331 The Potential of Ursolic Acid Acetate as an Agent for Malarial Chemotherapy

Authors: Mthokozisi B. C. Simelane

Abstract:

Despite the various efforts by governmental and non-governmental organizations aimed at eradicating the disease, malaria is said to kill a child every 30 seconds. Traditional healers use different concoctions prepared from medicinal plants to treat malaria. In the quest to bio-prospect plant-derived triterpenes for anti-malaria activity, we report here the in vivo antiplasmodial activity of ursolic acid acetate (ursolic acid isolated from dichloromethane extract of Mimusops caffra was chemically modified to its acetate derivative). The transdermal administration of ursolic acid acetate (UAA) dose dependently showed complete inhibition of the parasites’ growth at the highest concentration of 400 mg/kg after 15 days of Plasmodium berghei infection. UAA prevented the in vitro aggregation of MDH but did not prevent the expression of PfHsp 70 in E. coli XL1 blue cells. It, however, enhanced PfHsp70 ATPase activity with the specific activity of 65 units (amount of phosphate released 73.83 nmolPi/min.mg). Ursolic acid acetate prevented the formation of hemozoin (60 ± 0.02% at 6 mg/ml). The results suggest that Ursolic acid acetate possesses potential anti-malaria properties.

Keywords: Mimusops caffra, ursolic acid acetate, hemozoin, Malaria

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330 Isolation and Synthesis of 1’-S-1’-Acetoxycavicol Acetate as Potent Antidandruff Agent

Authors: M. Vijaya Bhaskar Reddy

Abstract:

The air-dried and powdered methanol solvent extraction of the rhizomes of Alpinia galangal is subjected to bio-assay guided fractionation and isolation yielded a known compound namely, 1'-S-1'-Acetoxychavicol acetate (1). The isolated known compound has been identified based on the physical, spectral data (IR, ¹H, ¹³C, NMR and mass spectroscopy) and comparison with an authentic sample. Finally isolated 1'-S-1'-Acetoxychavicol acetate (1) was confirmed by synthesis. The crude methanol extract and identified known compound (1) were tested for antidandruff property against Malassezia furfur showed with MIC 1000 µg/mL and 7.81 µg/mL, respectively.

Keywords: Alpinia galanga, isolation, 1'-S-1'-Acetoxychavicol acetate, antidandruff activity, Malassezia furfur

Procedia PDF Downloads 76
329 Antibacterial and Antityrosinase Activity of Isolated Compounds from Stem Bark of Ficus platyphylla Del

Authors: Aminu Muhammad, Mustapha Ya’u, Hasnah Mohd Sirat

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An investigation of the chemical constituents into the stem bark of Ficus platyphylla (Moraceae) has resulted in the isolation of hordenine, epicatechin, lupeol, lupeol acetate and α-amyrin acetate. Their structures were determined using spectroscopic data as well as comparison with literature data. The antibacterial assay has been tested against Gram positive and Gram negative bacteria, while the tyrosinase inhibition assay was examined using L-Dopa as a substrate of mushroom tyrosinase enzyme. hordenine, epicatechin, lupeol, lupeol acetate and α-amyrin acetate showed minimum inhibition concentration (MIC) values in the range of 225-900 µg/mL against the bacterial strains. Lupeol, lupeol acetate and α-amyrin acetate showed significant antityrosinase activity against mushroom tyrosinase enzyme with percent inhibition of 67.7%, 66.2% and 62.2%, respectively.

Keywords: antibacterial, antityrosinase, chemical constituents, Ficus platyphylla

Procedia PDF Downloads 186
328 Glycerol-Free Biodiesel Synthesis from Crude Mahua (Madhuca indica) Oil under Supercritical Methyl Acetate Using CO2 as a Co-Solvent

Authors: Antaram Sarve, Mahesh Varma, Shriram Sonawane

Abstract:

Conventional route of producing biodiesel with alcohol produces glycerol as side product which leads to oversupply and devaluation in the world market. Supercritical methyl acetate (SCMA) has been proven to convert triglycerides into fatty acid methyl esters (FAMEs) and triacetin, which is a valuable biodiesel additive as side product rather than glycerol. However, due to the low reactivity of supercritical methyl acetate on triglycerides, high reaction conditions are required to obtained maximum yields. The present study describes the renewable approach for the production of biodiesel from low-cost, high acid value mahua oil under supercritical methyl acetate condition using carbon dioxide (CO2) as a co-solvent. CO2 was employed to decrease high reaction conditions required for supercritical methyl acetate transesterification. The influence of process parameters such as temperature, oil to methyl acetate molar ratio, reaction time, and the CO2 pressure was evaluated. The properties of biodiesel produced were found to be superior compared to conventional biodiesel method. Furthermore, SCMA has a high tolerance towards free fatty acids (FFAs) which is crucial to allow the utilization of inexpensive waste oils as a biodiesel feedstock.

Keywords: supercritical methyl acetate, CO2, biodiesel, fuel properties

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327 Sonochemical Zinc Oxide and Layered Hydroxy Zinc Acetate Synthesis in Fenton-Like Reactions

Authors: Durata Haciu, Ozgur Birer

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Zinc acetate solution is sonicated at high power in water and in ethanol in the absence and presence of various peroxides. In the absence of peroxides, the products are zinc oxide and layered hydroxy zinc acetate in water and in ethanol, respectively. Layered basic zinc acetate are prepared for the first time using sonochemical methods. The addition of peroxides alters the reaction mechanisms. In water, insoluble peroxides produce zinc oxides while the water soluble peroxide, i.e.hydrogen peroxide, completely destroyed the structure and casted a doubt on the accepted peroxide initiated mechanism of reactions. In ethanol,peroxide addition caused the reaction mechanism to change and some oxide formation is observed. The reaction mechanism is sensitive to water/ethanol amounts as well as the peroxide to zinc ion mole ratio.Thin zinc oxide wafers (ca. 30 nm) with band gaps of 3.24 eV were obtained.

Keywords: ultrasound, zinc oxide, hydroxy zinc acetate, fenton, peroxide initiation

Procedia PDF Downloads 220
326 Changes in Behavior and Learning Ability of Rats Intoxicated with Lead

Authors: A. Goma Amira, U. E. Mahrous

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Measuring the effect of perinatal lead exposure on learning ability of offspring is considered as a sensitive and selective index for providing an early marker for central nervous system damage produced by this toxic metal. A total of 35 Sprague-Dawley adult rats were used to investigate the effect of lead acetate toxicity on behavioral patterns of adult female rats and learning ability of offspring. Rats were allotted into 4 groups, group one received 1g/l lead acetate (n=10), group two received 1.5g/l lead acetate (n=10), group three received 2g/l lead acetate in drinking water (n=10), and control group did not receive lead acetate (n=5) from 8th day of pregnancy till weaning of pups. The obtained results revealed a dose-dependent increase in the feeding time, drinking frequency, licking frequency, scratching frequency, licking litters, nest building, and retrieving frequencies, while standing time increased significantly in rats treated with 1.5g/l lead acetate than other treated groups and control. On the contrary, lying time decreased gradually in a dose-dependent manner. Moreover, movement activities were higher in rats treated with 1g/l lead acetate than other treated groups and control. Furthermore, time spent in closed arms was significantly lower in rats given 2g/l lead acetate than other treated groups, while they spent significantly much time spent in open arms than other treated groups which could be attributed to occurrence of adaptation. Furthermore, number of entries in open arms was-dose dependent. However, the ratio between open/closed arms revealed a significant decrease in rats treated with 2g/l lead acetate than the control group.

Keywords: lead toxicity, rats, learning ability, behavior

Procedia PDF Downloads 308
325 Biodegradation Behavior of Cellulose Acetate with DS 2.5 in Simulated Soil

Authors: Roberta Ranielle M. de Freitas, Vagner R. Botaro

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The relationship between biodegradation and mechanical behavior is fundamental for studies of the application of cellulose acetate films as a possible material for biodegradable packaging. In this work, the biodegradation of cellulose acetate (CA) with DS 2.5 was analyzed in simulated soil. CA films were prepared by casting and buried in the simulated soil. Samples were taken monthly and analyzed, the total time of biodegradation was 6 months. To characterize the biodegradable CA, the DMA technique was employed. The main result showed that the time of exposure to the simulated soil affects the mechanical properties of the films and the values of crystallinity. By DMA analysis, it was possible to conclude that as the CA is biodegraded, its mechanical properties were altered, for example, storage modulus has increased with biodegradation and the modulus of loss has decreased. Analyzes of DSC, XRD, and FTIR were also carried out to characterize the biodegradation of CA, which corroborated with the results of DMA. The observation of the carbonyl band by FTIR and crystalline indices obtained by XRD were important to evaluate the degradation of CA during the exposure time.

Keywords: biodegradation, cellulose acetate, DMA, simulated soil

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324 Preparation of CuAlO2 Thin Films on Si or Sapphire Substrate by Sol-Gel Method Using Metal Acetate or Nitrate

Authors: Takashi Ehara, Takayoshi Nakanishi, Kohei Sasaki, Marina Abe, Hiroshi Abe, Kiyoaki Abe, Ryo Iizaka, Takuya Sato

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CuAlO2 thin films are prepared on Si or sapphire substrate by sol-gel method using two kinds of sols. One is combination of Cu acetate and Al acetate basic, and the other is Cu nitrate and Al nitrate. In the case of acetate sol, XRD peaks of CuAlO2 observed at annealing temperature of 800-950 ºC on both Si and sapphire substrates. In contrast, in the case of the films prepared using nitrate on Si substrate, XRD peaks of CuAlO2 have been observed only at the annealing temperature of 800-850 ºC. At annealing temperature of 850ºC, peaks of other species have been observed beside the CuAlO2 peaks, then, the CuAlO2 peaks disappeared at annealing temperature of 900 °C with increasing in intensity of the other peaks. Intensity of the other peaks decreased at annealing temperature of 950 ºC with appearance of broad SiO2 peak. In the present, we ascribe these peaks as metal silicide.

Keywords: CuAlO2, silicide, thin Films, transparent conducting oxide

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323 Hydrogel Based on Cellulose Acetate Used as Scaffold for Cell Growth

Authors: A. Maria G. Melero, A. M. Senna, J. A. Domingues, M. A. Hausen, E. Aparecida R. Duek, V. R. Botaro

Abstract:

A hydrogel from cellulose acetate cross linked with ethylenediaminetetraacetic dianhydride (HAC-EDTA) was synthesized by our research group, and submitted to characterization and biological tests. Cytocompatibility analysis was performed by confocal microscopy using human adipocyte derived stem cells (ASCs). The FTIR analysis showed characteristic bands of cellulose acetate and hydroxyl groups and the tensile tests evidence that HAC-EDTA present a Young’s modulus of 643.7 MPa. The confocal analysis revealed that there was cell growth at the surface of HAC-EDTA. After one day of culture the cells presented spherical morphology, which may be caused by stress of the sequestration of Ca2+ and Mg2+ ions at the cell medium by HAC-EDTA, as demonstrated by ICP-MS. However, after seven days and 14 days of culture, the cells present fibroblastoid morphology, phenotype expected by this cellular type. The results give efforts to indicate this new material as a potential biomaterial for tissue engineering, in the future in vivo approach.

Keywords: cellulose acetate, hydrogel, biomaterial, cellular growth

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322 CuO Thin Films Deposition by Spray Pyrolysis: Influence of Precursor Solution Properties

Authors: M. Lamri Zeggar, F. Bourfaa, A. Adjimi, F. Boutebakh, M. S. Aida, N. Attaf

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CuO thin films were deposited by spray ultrasonic pyrolysis with different precursor solution. Two staring solution slats were used namely: Copper acetate and copper chloride. The influence of these solutions on CuO thin films proprieties of is instigated. The X rays diffraction (XDR) analysis indicated that the films deposed with copper acetate are amorphous however the films elaborated with copper chloride have monoclinic structure. UV- Visible transmission spectra showed a strong absorbance of the deposited CuO thin films in the visible region. Electrical characterization has shown that CuO thin films prepared with copper acetate have a higher electrical conductivity.

Keywords: thin films, cuprous oxide, spray pyrolysis, precursor solution

Procedia PDF Downloads 235
321 Influence of [Emim][OAc] and Water on Gelatinization Process and Interactions with Starch

Authors: Shajaratuldur Ismail, Nurlidia Mansor, Zakaria Man

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Thermoplastic starch (TPS) plasticized by 1-ethyl-3-methylimidazolium acetate [Emim][OAc] were obtained through gelatinization process. The gelatinization process occurred in the presence of water and [Emim][OAc] as plasticizer at high temperature (90˚C). The influence of [Emim][OAc] and water on the gelatinization and interactions with starch have been studied over a range of compositions. The homogenous mass was obtained for the samples containing 35, 40 and 43.5 % of water contents which showed that water plays important role in gelatinization process. Detailed IR spectroscopy analysis showed decrease in hydrogen bonding intensity and strong interaction between acetate anion in [Emim][OAc] and starch hydroxyl groups in the presence of [Emim][OAc]. Starch-[Emim][OAc]-water mixture at 10-3-8.7 presented homogenous mass, less hydrogen bonding intensity and strong interaction between acetate anion in [Emim][OAc] and starch hydroxyl groups.

Keywords: starch, ionic liquid, 1-ethyl-3-methylimidazolium acetate, plasticizer, gelatinization, IR spectroscopy

Procedia PDF Downloads 163
320 Investigation of Astrocyte Physiology on Stiffness-Controlled Cellulose Acetate Nanofiber as a Tissue Scaffold

Authors: Sun Il Yu, Jung Hyun Joo, Hwa Sung Shin

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Astrocytes are known as dominant cells in CNS and play a role as a supporter of CNS activity and regeneration. Recently, three-dimensional culture of astrocytes were actively applied to understand in vivo astrocyte works. Electrospun nanofibers are attractive for 3D cell culture system because they have a high surface to volume ratio and porous structure, and have already been used for 3D astrocyte cultures. In this research, the stiffness of cellulose acetate (CA) nanofiber was controlled by heat treatment. As stiffness increased, astrocyte cell viability and adhesion increased. Reactivity of astrocyte was also upregulated in stiffer CA nanofiber in terms of GFAP, an intermediate filament protein. Finally, we demonstrated that stiffness-controllable CA is attractive for astrocyte tissue engineering.

Keywords: astrocyte, cellulose acetate, nanofiber, tissue scaffold

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319 Chemical and Bioactive Constituents Isolated from the Formosa Zamia furfureace L.

Authors: Chien-Liang Chao, Yun-Sheng Lin

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Secondary metabolites are applied in the human life of the Chinese herbal medicine. Many drugs are originally extracted from natural products with combination of pharmaceutical and chemical studies. Crude extract of the leaves from Zamia furfureace L. has been shown to exhibit anticancer activities. The first chemical investigation of this plant was carried out by our group. In this study, four known compounds were isolated from Zamia furfureace L. with three lignins (Sesamin (1), Wodeshiol (2) and Paulownin (3)), and one dipeptide (Aurantiamide acetate (4)). The structures of these compounds were analyzed through the 1D-NMR(1H-NMR,13C-NMR)、2D-NMR(COSY、HMQC、HMBC、NOESY) spectroscopic analysis, and by comparison of variety of physical data (IR, mass spectrometry, ultraviolet, optical rotation). Among them, Aurantiamide acetate (4) exhibited weak cytotoxic activity against human gastric cancer cells.

Keywords: Zamia furfureace L., AGS, sesamin, Aurantiamide acetate, secondary metabolites

Procedia PDF Downloads 383
318 Effects of Rice Plant Extracts and Phenolic Allelochemicals on Seedling Growth of Radish

Authors: Mohammad Shamim Hasan Mandal, Phu Minh, Do Tan Khang, Phung Thi Tuyen, Tran Dang Xuan

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Rice (Oryza sativa L.) is one of the major crops of Vietnam which has more than thousands of varieties. Many of the local varieties have greater potentiality but they are in danger of extinct. Rice plant contains many secondary metabolites that are allelopathic to other plants. Seven rice varieties were cultivated in the field condition at Hiroshima University, Japan; stems and leaves from each variety were collected later, they were extracted with methanol, hexane, ethyl acetate, butanol, and water. Total phenolic content and total flavonoid contents were high in ethyl acetate extracts. DPPH antioxidant assay results showed that the ethyl acetate extracts had the higher IC50 value. Therefore, the ethyl acetate extracts were selected for laboratory experimentation through petri dish assay. Results showed that the two-local variety Re nuoc and Nan chon completely inhibited the germination of radish seedlings. Further laboratory bioassay and field experimentation will be conducted to validate the laboratory bioassay findings.

Keywords: allelopathy, bioassay, Oryza sativa, Raphanus sativus

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317 Study of the Protective Effects of Summer Savory against Multiple Organ Damage Induced by Lead Acetate in Rats

Authors: Bassant M. M. Ibrahim, Doha H. Abou Baker, Ahmed Abd Elghafour

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Excessive exposure to heavy metals contributes to the occurrence of deleterious health problems that affect vital organs like the brain, liver, kidneys, and heart. The use of natural products that have antioxidant capabilities may contribute to the protection of these organs. In the present study, the essential oil of summer savory (Satureja hortensis) was used to evaluate its protective effects against lead acetate induced damaging effect on rats’ vital organs, due to its high contents of carvacrol, y-terpinene, and p-cymene. Forty female Wister Albino rats were classified into five equal groups, the 1st served as normal group, the 2nd served as positive control group was given lead acetate (60 mg/kg) intra-peritoneal (IP), the third to fifth groups were treated with calcium disodium (EDTA) as chelating agent and summer savory essential oil in doses of (50 and 100mg/kg) respectively. All treatments were given IP concomitant with lead acetate for ten successive days. At the end of the experiment duration electrocardiogram (ECG), an open field test for the evaluation of psychological state, rotarod test as for the evaluation of locomotor coordination ability as well as anti-inflammatory and oxidative stress biomarkers in serum and histopathology of vital organs were performed. The investigations in this study show that the protective effect of high dose of summer savory essential oil is more than the low dose and that the essential oil of summer savory is a promising agent that can contribute to the protection of vital organs against the hazardous damaging effects of lead acetate.

Keywords: brain, heart, kidneys, lead acetate, liver, protective, summer savory

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316 Graft Copolymerization of Cellulose Acetate with Nitro-N-Amino Phenyl Maleimides

Authors: Azza. A. Al-Ghamdi, Abir. A. Abdel-Naby

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The construction of Nitro -N-amino phenyl maleimide branches onto Cellulose acetate (CA) substrate by free radical graft copolymerization using benzoyl peroxide as initiator led to formation of highly thermal stable copolymers as shown from the results of gravimetric analysis (TGA). CA-g-2,4-dinitro amino phenyl maleimide exhibited higher thermal stability than the CA-g-4-nitro amino phenyl maleimide as shown from the initial decomposition temperature (To). This is due to the ability of nitro group to form hydrogen bonding with hydroxyl group of the glucopyranose ring which increases the crystallinity of polymeric matrix. The crystalline shapes representing the graft part are clearly distinct in the Emission scanning electron microscope (ESEM) morphology of the copolymer. A suggested reaction mechanism for the grafting process was also discussed.

Keywords: Cellulose acetate, Crystallinity, Graft copolymerization, Thermal properties

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315 Cellulose Acetate/Polyacrylic Acid Filled with Nano-Hydroxapatite Composites: Spectroscopic Studies and Search for Biomedical Applications

Authors: E. M. AbdelRazek, G. S. ElBahy, M. A. Allam, A. M. Abdelghany, A. M. Hezma

Abstract:

Polymeric biocomposite of hydroxyapatite/polyacrylic acid were prepared and their thermal and mechanical properties were improved by addition of cellulose acetate. FTIR spectroscopy technique and X-ray diffraction analysis were employed to examine the physical and chemical characteristics of the biocomposites. Scanning electron microscopy shows a uniform distribution of HAp nano-particles through the polymeric matrix of two organic/inorganic composites weight ratios (60/40 and 70/30), at which the material crystallinity reaches a considerable value appropriate for the needed applications were studied and revealed that the HAp nano-particles are uniformly distributed in the polymeric matrix. Kinetic parameters were determined from the weight loss data using non isothermal thermogravimetric analysis (TGA). Also, the main degradation steps were described and discussed. The mechanical properties of composites were evaluated by measuring tensile strength and elastic modulus. The data indicate that the addition of cellulose acetate can make homogeneous composites scaffold significantly resistant to higher stress. Elastic modulus of the composites was also improved by the addition of cellulose acetate, making them more appropriate for bioapplications.

Keywords: biocomposite, chemical synthesis, infrared spectroscopy, mechanical properties

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314 Synergistic Effect of Eugenol Acetate with Betalactam Antibiotic on Betalactamase and Its Bioinformatics Analysis

Authors: Vinod Nair, C. Sadasivan

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Beta-lactam antibiotics are the most frequently prescribed medications in modern medicine. The antibiotic resistance by the production of enzyme beta-lactamase is an important mechanism seen in microorganisms. Resistance to beta-lactams mediated by beta-lactamases can be overcome successfully with the use of beta-lactamase inhibitors. New generations of the antibiotics contain mostly synthetic compounds, and many side effects have been reported for them. Combinations of beta-lactam and beta-lactamase inhibitors have become one of the most successful antimicrobial strategies in the current scenario of bacterial infections. Plant-based drugs are very cheap and having lesser adverse effect than synthetic compounds. The synergistic effect of eugenol acetate with beta-lactams restores the activity of beta-lactams, allowing their continued clinical use. It is reported here the enhanced inhibitory effect of phytochemical, eugenol acetate, isolated from the plant Syzygium aromaticum with beta-lactams on beta-lactamase. The compound was found to have synergistic effect with the antibiotic amoxicillin against antibiotic-resistant strain of S.aureus. The enzyme was purified from the organism and incubated with the compound. The assay showed that the compound could inhibit the enzymatic activity of beta-lactamase. Modeling and molecular docking studies indicated that the compound can fit into the active site of beta-lactamase and can mask the important residue for hydrolysis of beta-lactams. The synergistic effects of eugenol acetate with beta-lactam antibiotics may justify, the use of these plant compounds for the preparation of β-lactamase inhibitors against β-lactam resistant S.aureus.

Keywords: betalactamase, eugenol acetate, synergistic effect, molecular modeling

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313 Sustainable and Efficient Recovery of Polyhydroxyalkanoate Polymer from Cupriavidus necator Using Environment Friendly Solvents

Authors: Geeta Gahlawat, Sanjeev Kumar Soni

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An imprudent use of environmentally hazardous petrochemical-based plastics and limited availability of fossil fuels have provoked research interests towards production of biodegradable plastics - polyhydroxyalkanoate (PHAs). However, the industrial application of PHAs based products is primarily restricted by their high cost of recovery and extraction protocols. Moreover, solvents used for the extraction and purification are toxic and volatile which causes adverse environmental hazards. Development of efficient downstream recovery strategies along with utilization of non-toxic solvents will accelerate their commercialization. In this study, various extraction strategies were designed for sustainable and cost-effective recovery of PHAs from Cupriavidus necator using non-toxic environment friendly solvents viz. 1,2-propylene carbonate, ethyl acetate, isoamyl alcohol, butyl acetate. The effect of incubation time i.e. 10, 30 and 50 min and temperature i.e. 60, 80, 100, 120°C was tested to identify the most suitable solvent. PHAs extraction using a recyclable solvent, 1,2 propylene carbonate, showed the highest recovery yield (90%) and purity (93%) at 120°C and 30 min incubation. Ethyl acetate showed the better capacity to recover PHAs from cells than butyl acetate. Extraction with ethyl acetate exhibited high recovery yield and purity of 96% and 92%, respectively at 100°C. Effect of non-toxic surfactant such as linear alkylbenzene sulfonic acid (LAS) was also studied at 40, 60 and 80°C, and detergent pH range of 3.0, 5.0, 7.0 and 9.0 for the extraction of PHAs from the cells. LAS gave highest yield of 86% and purity of 88% at temperature 80°C and 5.0 pH.

Keywords: polyhydroxyalkanoates, Cupriavidus necator, extraction, recovery yield

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312 Testing of the Decreasing Bond Strength of Polyvinyl Acetate Adhesive by Low Temperatures

Authors: Pavel Boška, Jan Bomba, Tomáš Beránek, Jiří Procházka

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When using wood products bonded by polyvinyl acetate, glues such as windows are the most limiting element of degradation of the glued joint due to weather changes. In addition to moisture and high temperatures, the joint may damage the low temperature below freezing point, where dimensional changes in the material and distortion of the adhesive film occur. During the experiments, the joints were exposed to several degrees of sub-zero temperatures from 0 °C to -40 °C and then to compare how the decreasing temperature affects the strength of the joint. The experiment was performed on wood beech samples (Fagus sylvatica), bonded with PVAc with D3 resistance and the shear strength of bond was measured. The glued and treated samples were tested on a laboratory testing machine, recording the strength of the joint. The statistical results have given us information that the strength of the joint gradually decreases with decreasing temperature, but a noticeable and statistically significant change is achieved only at very low temperatures.

Keywords: adhesives, bond strength, low temperatures, polyvinyl acetate

Procedia PDF Downloads 267
311 Identification of Active Phytocomponents in the Ethyl Acetate Extract of Glycosmis pentaphylla Retz. DC by Using GC-MS

Authors: M. Sivakumar, D. Chamundeeswari

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Glycosmis pentaphylla is one of the medicinally important plants belonging to the family Rutaceae, commonly known as “Anam or Panal” in Tamil. Traditionally, leaves are useful in fever, hepatopathy, eczema, skin disease, helminthiasis, wounds, and erysipelas. The fruits are sweet and are useful in vitiated conditions of vata, kapha, cough, and bronchitis. The roots are good for facial inflammations, rheumatism, jaundice, and anemia. The preliminary phytochemical investigations indicated the presence of alkaloids, terpenoids, flavonoids, tannins, sugar, glycoside, and phenolic compounds. In the present study, the root part of Glycosmis pentaphylla was used, and the root was collected from Western Ghats of South India. The root was sun/shade dried and pulverized to powder in a mechanical grinder. The powder was successively extracted with various solvents, and the ethyl acetate extract of Glycosmis pentaphylla has been subjected to the GC-MS analysis. Amongst the 46 chemical constituents identified from this plant, three major phytoconstituents were reported for the first time. Marmesin, a furanocumarin compound with the chemical structure 7H-Furo (3,2-G) (1)Benzopyran-7-one,2,3–dihydro–2 - (1-Hydroxy-1methylethyl)-(s) is one of the three compounds identified for the first time at the concentration of 11-60% in ethyl acetate extract of Glycosmis pentaphylla. Others include, Beta.-Fagarine (4.71%) and Paverine (13.08%).

Keywords: ethyl acetate extract, Glycosmis pentaphylla, GC-MS analysis, Phytochemicals

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310 The Feasibility of Anaerobic Digestion at 45⁰C

Authors: Nuruol S. Mohd, Safia Ahmed, Rumana Riffat, Baoqiang Li

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Anaerobic digestion at mesophilic and thermophilic temperatures have been widely studied and evaluated by numerous researchers. Limited extensive research has been conducted on anaerobic digestion in the intermediate zone of 45°C, mainly due to the notion that limited microbial activity occurs within this zone. The objectives of this research were to evaluate the performance and the capability of anaerobic digestion at 45°C in producing class A biosolids, in comparison to a mesophilic and thermophilic anaerobic digestion system operated at 35°C and 55°C, respectively. In addition to that, the investigation on the possible inhibition factors affecting the performance of the digestion system at this temperature will be conducted as well. The 45°C anaerobic digestion systems were not able to achieve comparable methane yield and high-quality effluent compared to the mesophilic system, even though the systems produced biogas with about 62-67% methane. The 45°C digesters suffered from high acetate accumulation, but sufficient buffering capacity was observed as the pH, alkalinity and volatile fatty acids (VFA)-to-alkalinity ratio were within recommended values. The accumulation of acetate observed in 45°C systems were presumably due to the high temperature which contributed to high hydrolysis rate. Consequently, it produced a large amount of toxic salts that combined with the substrate making them not readily available to be consumed by methanogens. Acetate accumulation, even though contributed to 52 to 71% reduction in acetate degradation process, could not be considered as completely inhibitory. Additionally, at 45°C, no ammonia inhibition was observed and the digesters were able to achieve volatile solids (VS) reduction of 47.94±4.17%. The pathogen counts were less than 1,000 MPN/g total solids, thus, producing Class A biosolids.

Keywords: 45°C anaerobic digestion, acetate accumulation, class A biosolids, salt toxicity

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309 Cytotoxic Effect of Crude Extract of Sea Pen Virgularia gustaviana on HeLa and MDA-MB-231 Cancer Cell Lines

Authors: Sharareh Sharifi, Pargol Ghavam Mostafavi, Ali Mashinchian Moradi, Mohammad Hadi Givianrad, Hassan Niknejad

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Marine organisms such as soft coral, sponge, ascidians, and tunicate containing rich source of natural compound have been studied in last decades because of their special chemical compounds with anticancer properties. The aim of this study was to investigate anti-cancer property of ethyl acetate extracted from marine sea pen Virgularia gustaviana found from Persian Gulf coastal (Bandar Abbas). The extraction processes were carried out with ethyl acetate for five days. Thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) were used for qualitative identification of crude extract. The viability of HeLa and MDA-Mb-231 cancer cells was investigated using MTT assay at the concentration of 25, 50, and a 100 µl/ml of ethyl acetate is extracted. The crude extract of Virgularia gustaviana demonstrated ten fractions with different Retention factor (Rf) by TLC and Retention time (Rt) evaluated by HPLC. The crude extract dose-dependently decreased cancer cell viability compared to control group. According to the results, the ethyl acetate extracted from Virgularia gustaviana inhibits the growth of cancer cells, an effect which needs to be further investigated in the future studies.

Keywords: anti-cancer, Hela cancer cell, MDA-Md-231 cancer cell, Virgularia gustavina

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308 Effect of Variable Fluxes on Optimal Flux Distribution in a Metabolic Network

Authors: Ehsan Motamedian

Abstract:

Finding all optimal flux distributions of a metabolic model is an important challenge in systems biology. In this paper, a new algorithm is introduced to identify all alternate optimal solutions of a large scale metabolic network. The algorithm reduces the model to decrease computations for finding optimal solutions. The algorithm was implemented on the Escherichia coli metabolic model to find all optimal solutions for lactate and acetate production. There were more optimal flux distributions when acetate production was optimized. The model was reduced from 1076 to 80 variable fluxes for lactate while it was reduced to 91 variable fluxes for acetate. These 11 more variable fluxes resulted in about three times more optimal flux distributions. Variable fluxes were from 12 various metabolic pathways and most of them belonged to nucleotide salvage and extra cellular transport pathways.

Keywords: flux variability, metabolic network, mixed-integer linear programming, multiple optimal solutions

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307 Evaluation of the Anti Ulcer Activity of Ethyl Acetate Fraction of Methanol Leaf Extract of Clerodendrum Capitatum

Authors: M. N. Ofokansi, Onyemelukwe Chisom, Amauche Chukwuemeka, Ezema Onyinye

Abstract:

The leaves of Clerodendrumcapitatum(Lamiaceae) is mostly used in the treatment of gastric ulcer in Nigerian folk medicine. The aim of this study was to evaluate the antiulcer activity of its crude methanol leaf extract and its ethyl acetate fraction in white albino rats. The effect of crude methanol leaf extract and its ethyl acetate fraction(250mg/kg, 500mg/kg) was evaluated using an absolute ethanol induced ulcer model. Crude methanol leaf extract and the ethyl acetate fraction was treated with distilled water and 6% Tween 80, respectively. crude methanol leaf extract was further investigated using a pylorus ligation induced ulcer model. Omeprazole was used as the standard treatment. Four groups of five albino rats of either sex were used. Parameters such as mean ulcer index and percentage ulcer protection were assessed in the ethanol-induced ulcer model, while the gastric volume, pH, and total acidity were assessed in the pyloric ligation induced ulcer model. Crude methanol leaf extract of Clerodendrumcapitatum(500mg/kg) showed a very highly significant reduction in mean ulcer index(p<0.001) in the absolute ethanol-induced model. ethyl acetate fraction of crude methanol leaf extract of Clerodendrumcapitatum(250mg/kg,500mg/kg) showed a very highly significant dose-dependent reduction in mean ulcer indices (p<0.001) in the absolute ethanol-induced model. The mean ulcer indices (1.6,2.2) with dose concentration (250mg/kg, 500mg/kg) of ethyl acetate fraction increased with ulcer protection (82.85%,76.42%) respectively when compared to the control group in the absolute ethanol-induced ulcer model. Crude methanol leaf extract of Clerodendrumcapitatum(250mg/kg, 500mg/kg) treated animals showed a highly significant dose-dependent reduction in mean ulcer index(p<0.01) with an increase in ulcer protection (56.77%,63.22%) respectively in pyloric ligated induced, ulcer model. Gastric parameters such as volume of gastric juice, pH, and total acidity were of no significance in the different doses of the crude methanol leaf extract when compared to the control group. The phytochemical investigation showed that the crude methanol leaf extracts Possess Saponins and Flavonoids while its ethyl acetate fraction possess only Flavonoids. The results of the study indicate that the crude methanol leaf extract and its ethyl acetate fraction is effective and has gastro protective and ulcer healing capacity. Ethyl acetate fraction is more potent than crude methanol leaf extract against ethanol-induced This result provides scientific evidence as a validation for its folkloric use in the treatment of gastric ulcer.

Keywords: gastroprotective, herbal medicine, anti-ulcer, pharmacology

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306 Bioassay Guided Isolation of Antimicrobial and Cytotoxic Components from Ethyl Acetate Extracts of Cassia Sieberiana D.C. (Fabaceae)

Authors: Abubakar Sani

Abstract:

The leaves extracts of Cassia sieberiana D.C. were screened for cytotoxicity using Brine Shrimp Test (BST) and antimicrobial bioassay against Staphylococcus aureus, Salmonella typhi and Escherichia coli using crude ethanol extract, Chloroform soluble fraction, aqueous soluble fraction, ethyl acetate soluble fraction, methanol soluble fraction and n-hexane soluble fraction. The Ethyl acetate fraction obtained proved to be most active in inducing complete lethality at minimum doses in BST and also active on Salmonella typhi. The Bioactivity result was used to guide the column chromatography which led to the isolation of pure compound CSB-8 which was found active in the BST with LC₅₀ value of 34(722-182)µg/ml and showed remarkable activity on Salmonella typhi (zone of inhibition 25mm) at 10,000µg/ml. The ¹H-NMR, ¹³C NMR, FTIR and GC-MS spectra of compound suggested the proposed structure to be 2-pentadecanone.

Keywords: brine shrimp, Cassia sieberiana D. C, Column chromatography, antimicrobial bioassay

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305 Linking Metabolism, Pluripotency and Epigenetic Changes during Early Differentiation of Embryonic Stem Cells

Authors: Arieh Moussaieff, Bénédicte Elena-Herrmann, Yaakov Nahmias, Daniel Aberdam

Abstract:

Differentiation of pluripotent stem cells is a slow process, marked by the gradual loss of pluripotency factors over days in culture. While the first few days of differentiation show minor changes in the cellular transcriptome, intracellular signaling pathways remain largely unknown. Recently, several groups demonstrated that the metabolism of pluripotent mouse and human cells is different from that of somatic cells, showing a marked increase in glycolysis previously identified in cancer as the Warburg effect. Here, we sought to identify the earliest metabolic changes induced at the first hours of differentiation. High-resolution NMR analysis identified 35 metabolites and a distinct, gradual transition in metabolism during early differentiation. Metabolic and transcriptional analyses showed the induction of glycolysis toward acetate and acetyl-coA in pluripotent cells, and an increase in cholesterol biosynthesis during early differentiation. Importantly, this metabolic pathway regulated differentiation of human and mouse embryonic stem cells. Acetate delayed differentiation preventing differentiation-induced histone de-acetylation in a dose-dependent manner. Glycolytic inhibitors upstream of acetate caused differentiation of pluripotent cells, while those downstream delayed differentiation. Our data suggests that a rapid loss of glycolysis in early differentiation down-regulates acetate and acetyl-coA production, causing a loss of histone acetylation and concomitant loss of pluripotency. It demonstrate that pluripotent stem cells utilize a novel metabolism pathway to maintain pluripotency through acetate/acetyl-coA and highlights the important role metabolism plays in pluripotency and early differentiation of stem cells.

Keywords: pluripotency, metabolomics, epigenetics, acetyl-coA

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304 Fabrication of Cellulose Acetate/Polyethylene Glycol Membranes Blended with Silica and Carbon Nanotube for Desalination Process

Authors: Siti Nurkhamidah, Yeni Rahmawati, Fadlilatul Taufany, Eamor M. Woo, I Made P. A. Merta, Deffry D. A. Putra, Pitsyah Alifiyanti, Krisna D. Priambodo

Abstract:

Cellulose acetate/polyethylene glycol (CA/PEG) membrane was modified with varying amount of silica and carbon nanotube (CNT) to enhance its separation performance in the desalination process. These composite membranes were characterized for their hydrophilicity, morphology and permeation properties. The experiment results show that hydrophilicity of CA/PEG/Silica membranes increases with the increasing of silica concentration and the decreasing particle size of silica. From Scanning Electron Microscopy (SEM) image, it shows that pore structure of CA/PEG membranes increases with the addition of silica. Membrane performance analysis shows that permeate flux, salt rejection, and permeability of membranes increase with the increasing of silica concentrations. The effect of CNT on the hydrophylicity, morphology, and permeation properties was also discussed.

Keywords: carbon nanotube, cellulose acetate, desalination, membrane, PEG

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303 The Effect of Floor Impact Sound Insulation Performance Using Scrambled Thermoplastic Poly Urethane and Ethylene Vinyl Acetate

Authors: Bonsoo Koo, Seong Shin Hong, Byung Kwon Lee

Abstract:

Most of apartments in Korea have wall type structure that present poor performance regarding floor impact sound insulation. In order to minimize the transmission of floor impact sound, flooring structures are used in which an insulating material, 30 mm thickness pad of EPS or EVA, is sandwiched between a concrete slab and the finished mortar. Generally, a single-material pad used for insulation has a heavyweight impact sound level of 44~47 dB with 210 mm thickness slab. This study provides an analysis of the floor impact sound insulation performance using thermoplastic poly urethane (TPU), ethylene vinyl acetate (EVA), and expanded polystyrene (EPS) materials with buffering performance. Following mock-up tests the effect of lightweight impact sound turned out to be similar but heavyweight impact sound was decreased by 3 dB compared to conventional single material insulation pad.

Keywords: floor impact sound, thermoplastic poly urethane, ethylene vinyl acetate, heavyweight impact sound

Procedia PDF Downloads 331