Search results for: Poly (lactic acid).
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 850

Search results for: Poly (lactic acid).

790 Effect of Gamma Irradiation on the Microhardness of Polymer Blends of Poly (Ethyl Methacrylate)(Pema) and Poly (Ethylene Oxide) (Peo)

Authors: Sanjay Kumar Awasthi, Sunil Kumar Bajpai, Surendra Kumar Pandey, Ajay Utiye

Abstract:

The effect of gamma irradiation on micro-hardness of polymer blends of poly (ethyl methacrylate)(PEMA) and poly (ethylene oxide) (PEO) has been investigated to detect the radiation induced crosslinking. The blend system comprises a noncrystallizable polymer, PEMA and a crystallizable polymer, PEO. On irradiation, the overall hardness of the blend specimens for different dose levels infers occurrence of a crosslinking process. The radiation-induced crosslinking was greater for blends having lower concentration of PEO. However, increase in radiation dose causes softening of blend system due to radiation induced scissioning of the chains

Keywords: Microhardness, Radiation induced crosslinking, Solution cast technique, Vicker's hardness number.

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789 Millimeter Wave I/Q Generation with the Inductive Resonator Matched Poly-Phase Filter

Authors: Ki-Jin Kim, Sanghoon Park, K. H. Ahn

Abstract:

A way of generating millimeter wave I/Q signal using inductive resonator matched poly-phase filter is suggested. Normally the poly-phase filter generates quite accurate I/Q phase and magnitude but the loss of the filter is considerable due to series connection of passive RC components. This loss term directly increases system noise figure when the poly-phase filter is used in RF Front-end. The proposed matching method eliminates above mentioned loss and in addition provides gain on the passive filter. The working algorithm is illustrated by mathematical analysis. The generated I/Q signal is used in implementing millimeter wave phase shifter for the 60 GHz communication system to verify its effectiveness. The circuit is fabricated in 90 nm TSMC RF CMOS process under 1.2 V supply voltage. The measurement results showed that the suggested method improved gain by 6.5 dB and noise by 2.3 dB. The summary of the proposed I/Q generation is compared with previous works.

Keywords: Millimeter Wave Circuits, Local Distribution, I/Q Generator.

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788 Predicting Bridge Pier Scour Depth with SVM

Authors: Arun Goel

Abstract:

Prediction of maximum local scour is necessary for the safety and economical design of the bridges. A number of equations have been developed over the years to predict local scour depth using laboratory data and a few pier equations have also been proposed using field data. Most of these equations are empirical in nature as indicated by the past publications. In this paper attempts have been made to compute local depth of scour around bridge pier in dimensional and non-dimensional form by using linear regression, simple regression and SVM (Poly & Rbf) techniques along with few conventional empirical equations. The outcome of this study suggests that the SVM (Poly & Rbf) based modeling can be employed as an alternate to linear regression, simple regression and the conventional empirical equations in predicting scour depth of bridge piers. The results of present study on the basis of non-dimensional form of bridge pier scour indicate the improvement in the performance of SVM (Poly & Rbf) in comparison to dimensional form of scour.

Keywords: Modeling, pier scour, regression, prediction, SVM (Poly & Rbf kernels).

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787 The Catalytic Properties of PtSn/Al2O3 for Acetic Acid Hydrogenation

Authors: Mingchuan Zhou, Haitao Zhang, Hongfang Ma, Weiyong Ying

Abstract:

Alumina supported platinum and tin catalysts with different loadings of Pt and Sn were prepared and characterized by low temperature N2 adsorption/desorption, H2-temperature programed reduction and CO pulse chemisorption. Pt and Sn below 1% loading were suitable for acetic acid hydrogenation. The best performance over 0.75Pt1Sn/Al2O3 can reach 87.55% conversion of acetic acid and 47.39% selectivity of ethanol. The operating conditions of acetic acid hydrogenation over 1Pt1Sn/Al2O3 were investigated. High reaction temperature can enhance the conversion of acetic acid, but it decreased total selectivity of ethanol and acetyl acetate. High pressure and low weight hourly space velocity were beneficial to both conversion of acetic acid and selectivity to ethanol.

Keywords: Acetic acid, hydrogenation, PtSn, operating condition.

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786 A Comparison of Dilute Sulfuric and Phosphoric Acid Pretreatments in Biofuel Production from Corncobs

Authors: Jirakarn Nantapipat, Apanee Luengnaruemitchai, Sujitra Wongkasemjit

Abstract:

Biofuels, like biobutanol, have been recognized for being renewable and sustainable fuels which can be produced from lignocellulosic biomass. To convert lignocellulosic biomass to biofuel, pretreatment process is an important step to remove hemicelluloses and lignin to improve enzymatic hydrolysis. Dilute acid pretreatment has been successful developed for pretreatment of corncobs and the optimum conditions of dilute sulfuric and phosphoric acid pretreatment were obtained at 120 °C for 5 min with 15:1 liquid to solid ratio and 140 °C for 10 min with 10:1 liquid to solid ratio, respectively. The result shows that both of acid pretreatments gave the content of total sugar approximately 34–35 g/l. In case of inhibitor content (furfural), phosphoric acid pretreatment gives higher than sulfuric acid pretreatment. Characterizations of corncobs after pretreatment indicate that both of acid pretreatments can improve enzymatic accessibility and the better results present in corncobs pretreated with sulfuric acid in term of surface area, crystallinity, and composition analysis.

Keywords: Corncobs, Pretreatment, Sulfuric acid, Phosphoric acid.

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785 Optimization of Diluted Organic Acid Pretreatment on Rice Straw Using Response Surface Methodology

Authors: Rotchanaphan Hengaroonprasan, Malinee Sriariyanun, Prapakorn Tantayotai, Supacharee Roddecha, Kraipat Cheenkachorn

Abstract:

Lignocellolusic material is a substance that is resistant to be degraded by microorganisms or hydrolysis enzymes. To be used as materials for biofuel production, it needs pretreatment process to improve efficiency of hydrolysis. In this work, chemical pretreatments on rice straw using three diluted organic acids, including acetic acid, citric acid, oxalic acid, were optimized. Using Response Surface Methodology (RSM), the effect of three pretreatment parameters, acid concentration, treatment time, and reaction temperature, on pretreatment efficiency were statistically evaluated. The results indicated that dilute oxalic acid pretreatment led to the highest enhancement of enzymatic saccharification by commercial cellulase and yielded sugar up to 10.67 mg/ml when using 5.04% oxalic acid at 137.11 oC for 30.01 min. Compared to other acid pretreatment by acetic acid, citric acid, and hydrochloric acid, the maximum sugar yields are 7.07, 6.30, and 8.53 mg/ml, respectively. Here, it was demonstrated that organic acids can be used for pretreatment of lignocellulosic materials to enhance of hydrolysis process, which could be integrated to other applications for various biorefinery processes. 

Keywords: Lignocellolusic biomass, pretreatment, organic acid response surface methodology, biorefinery.

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784 Copolymers of Pyrrole and α,ω-Dithienyl Terminated Poly(ethylene glycol)

Authors: Nesrin Köken, Esin A. Güvel, Nilgün Kızılcan

Abstract:

This work presents synthesis of α,ω-dithienyl terminated poly(ethylene glycol) (PEGTh) capable for further chain extension by either chemical or electrochemical polymeriztion. PEGTh was characterized by FTIR and 1H-NMR. Further copolymerization of PEGTh and pyrrole (Py) was performed by chemical oxidative polymerization using ceric (IV) salt as an oxidant (PPy-PEGTh). PEG without end group modification was used directly to prepare copolymers with Py by Ce (IV) salt (PPy-PEG). Block copolymers with mole ratio of pyrrole to PEGTh (PEG) 50:1 and 10:1 were synthesized. The electrical conductivities of copolymers PPy-PEGTh and PPy-PEG were determined by four point probe technique. Influence of the synthetic route and content of the insulating segment on conductivity and yield of the copolymers were investigated.

Keywords: Chemical oxidative polymerization, conducting copolymer, poly(ethylene glycol), polypyrrole.

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783 Hydrolytic Properties of Ellagic Acid in Commercial Pomegranate Juices

Authors: Sibel Uzuner, Jale Acar

Abstract:

Pomegranate and pomegranate juices (PJs) have taken great attention for their health benefits in the last years. As there is an increasing concern about potential health benefits of ellagic acid, it is of great interest to evaluate alterations in ellagic acid concentration of commercial PJs. The purpose of this study is to analyze total phenolic, free and total ellagic acid content of six commercial PJs sold in Turkish markets using HPLC. The results showed that some commercial PJs had markedly high total phenolic and ellagic acid content. Total phenolic substances of commercial PJs range from 796.71 to 4608.91 mg GAE/l. Free amount of ellagic acid in commercial PJs range from 27.64 to 111.78 mg/l. Samples are hydrolyzed with concentrated HCl at 93oC for 2 and 24 hour and influences of temperature and time parameters on hydrolization were investigated. Thermal processing for pasteurization increased ellagic acid via ellagitannins hydrolysis.

Keywords: Ellagic acid, ellagitannin, pomegranate juice, total phenolic compounds

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782 Analysis of the Supramolecular Complex of Kinetin with Glycyrrhizic Acid Using the Chromatography Mass Spectrometry Method

Authors: B. Y. Matmuratov, S. D. Madrakhimova. R. S. Esanov. A. D. Matchanov

Abstract:

Supramolecular complexes of glycyrrhizic acid with kinetin in various molar ratios were obtained, physico-chemical parameters and spectral properties of the resulting complexes were studied (UV, IR, mass spectrometry.

Keywords: Monoammonium salt of glycyrrhizic acid, glycyrrhizic acid, supramolecular complex, isomolar series, IR spectroscopy.

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781 Solid-State Bioconversion of Pineapple Residues into Kojic Acid by Aspergillus flavus: A Prospective Study

Authors: S. Nurashikin, E. Z. Rusley, A. Husaini

Abstract:

Kojic acid is an organic acid that is widely used as an ingredient for dermatological products, precursor for flavor enhancer and also as anti-inflammatory drug. The present study was undertaken to test the feasibility of pineapple residues as substrate for kojic acid production by Aspergillus flavus Link 44-1 via solid-state fermentation. The effect of initial moisture content, pH and incubation time on kojic acid fermentation was investigated. The best initial moisture content for kojic acid production from pineapple residues was observed at 70% (v/w) whereas initial culture pH 2.5 was identified to give high production of kojic acid. The optimal range of incubation time was identified between 8 and 14 days of incubation which corresponded to highest range of kojic acid produced. The results from this study pronounce the promising usability of pineapple residues as alternative substrate for kojic acid production by A. flavus Link 44-1.

Keywords: Aspergillus flavus, kojic acid, pineapple residues, solid state fermentation.

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780 Growth Behaviors, Thermostable Direct Hemolysin Secretion and Fatty Acid Profiles of Acid-adapted and Non-adapted Vibrio parahaemolyticus

Authors: Ming-Lun Chiang, Chieh Wu, Ming-Ju Chen

Abstract:

Three strains of Vibrio parahaemolyticus (690, BCRC 13023 and BCRC 13025) implicated in food poisoning outbreaks in Taiwan were subjected to acid adaptation at pH 5.5 for 90 min. The growth behaviors of acid-adapted and non-adapted V. parahaemolyticus in the media supplemented with various nitrogen and carbon sources were investigated. The effects of acid adaptation on the thermostable direct hemolysin (TDH) secretion and fatty acid profiles of V. parahaemolyticus were also examined. Results showed that acid-adapted and non-adapted V. parahaemolyticus 690, BCRC 13023 and BCRC 13025 grew similarly in TSB-3% NaCl and basal media supplemented with various carbon and nitrogen sources during incubation period. Higher TDH secretion was noted with V. parahaemolyticus 690 among the three strains. However, acid-adapted strains produced less amounts of TDH than non-adapted strains when they were grown in TSB-3% NaCl. Additionally, acid adaptation increased the ratio of SFA/USFA in cells of V. parahaemolyticus strains.

Keywords: Vibrio parahaemolyticus, acid adaptation, thermostable direct hemolysin, fatty acid profile.

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779 Growth Effects of Caffeic Acid and Thioglycolic Acid Modified Chitosans in U937 Cells

Authors: Aytekin A.O., Morimura S.

Abstract:

Chitosan is a biopolymer composed of glucosamine and N-acetyl glucosamine. Solubility and viscosity pose problems in some applications. These problems can be overcome with unique modifications. In this study, firstly, chitosan was modified by caffeic acid and thioglycolic acid, separately. Then, growing effects of these modified polymers was observed in U937 cell line. Caffeic acid is a phenolic compound and its modifications act carcinogenic inhibitors in drugs. Thiolated chitosans are commonly being used for drugdelivery systems in various routes, because of enhancing mucoadhesiveness property. U937 cell line was used model cell for leukaemia. Modifications were achieved by 1 – 15 % binding range. Increasing binding ratios showed higher radical-scavenging activity and reducing cell growth, in compared to native chitosan. Caffeic acid modifications showed higher radical-scavenging activity than thiolated chitosans at the same concentrations. Caffeic acid and thioglycolic acid modifications inhibited growth of U937, effectively.

Keywords: Chitosan, U937 cell, caffeic acid, thioglycolic acid

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778 Study of Encapsulation of Quantum Dots in Polystyrene and Poly (E-Caprolactone)Microreactors Prepared by Microvolcanic Eruption of Freeze Dried Microspheres

Authors: Deepak Kukkar, Inderpreet Kaur, Jagtar Singh, Lalit M Bharadwaj

Abstract:

Polymeric microreactors have emerged as a new generation of carriers that hold tremendous promise in the areas of cancer therapy, controlled delivery of drugs, for removal of pollutants etc. Present work reports a simple and convenient methodology for synthesis of polystyrene and poly caprolactone microreactors. An aqueous suspension of carboxylated (1μm) polystyrene latex particles was mixed with toluene solution followed by freezing with liquid nitrogen. Freezed particles were incubated at -20°C and characterized for formation of voids on the surface of polymer microspheres by Field Emission Scanning Electron Microscope. The hollow particles were then overnight incubated at 40ºC with unfunctionalized quantum dots (QDs) in 5:1 ratio. QDs Encapsulated polystyrene microcapsules were characterized by fluorescence microscopy. Likewise Poly ε-caprolactone microreactors were prepared by micro-volcanic rupture of freeze dried microspheres synthesized using emulsification of polymer with aqueous Poly vinyl alcohol and freezed with liquid nitrogen. Microreactors were examined with Field Emission Scanning Electron Microscope for size and morphology. Current study is an attempt to create hollow polymer particles which can be employed for microencapsulation of nanoparticles and drug molecules.

Keywords: FE-SEM, Microreactors, Microvolcanic rupture, Poly (ε-caprolactone), Polystyrene

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777 pH-Responsiveness Properties of a Biodigradable Hydrogels Based on Carrageenan-g-poly(NaAA-co-NIPAM)

Authors: Mohammad Sadeghi, Behrouz Heidari, Korush Montazeri

Abstract:

A novel thermo-sensitive superabsorbent hydrogel with salt- and pH-responsiveness properties was obtained by grafting of mixtures of acrylic acid (AA) and N-isopropylacrylamide (NIPAM) monomers onto kappa-carrageenan, kC, using ammonium persulfate (APS) as a free radical initiator in the presence of methylene bisacrylamide (MBA) as a crosslinker. Infrared spectroscopy was carried out to confirm the chemical structure of the hydrogel. Moreover, morphology of the samples was examined by scanning electron microscopy (SEM). The effect of MBA concentration and AA/NIPAM weight ratio on the water absorbency capacity has been investigated. The swelling variations of hydrogels were explained according to swelling theory based on the hydrogel chemical structure. The hydrogels exhibited salt-sensitivity and cation exchange properties. The temperature- and pH-reversibility properties of the hydrogels make the intelligent polymers as good candidates for considering as potential carriers for bioactive agents, e.g. drugs.

Keywords: superabsorbent, carrageenan, acrylic acid, Nisopropylacrylamide, hydrogel, swelling

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776 Effect of Acid Adaptation on the Survival of Three Vibrio parahaemolyticus Strains under Simulated Gastric Condition and their Protein Expression Profiles

Authors: Ming-Lun Chiang, Hsi-Chia Chen, Chieh Wu, Yu-Ting Tseng, Ming-Ju Chen

Abstract:

In this study, three strains of Vibrio parahaemolyticus (690, BCRC 13023 and BCRC 13025) were subjected to acid adaptation at pH 5.5 for 90 min. The survival of acid-adapted and non-adapted V. parahaemolyticus strains under simulated gastric condition and their protein expression profiles were investigated. Results showed that acid adaptation increased the survival of the test V. parahaemolyticus strains after exposure to simulated gastric juice (pH 3). Additionally, acid adaptation also affected the protein expression in these V. parahaemolyticus strains. Nine proteins, identified as atpA, atpB, DnaK, GroEL, OmpU, enolase, fructose-bisphosphate aldolase, phosphoglycerate kinase and triosephosphate isomerase, were induced by acid adaptation in two or three of the test strains. These acid-adaptive proteins may play important regulatory roles in the acid tolerance response (ATR) of V. parahaemolyticus.

Keywords: Acid adaptation, protein expression, simulated gastric juice, Vibrio parahaemolyticus

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775 Layer-by-Layer Deposition of Poly (Ethylene Imine) Nanolayers on Polypropylene Nonwoven Fabric. Electrostatic and Thermal Properties

Authors: Dawid Stawski, Silviya Halacheva, Dorota Zielińska

Abstract:

The surface properties of many materials can be readily and predictably modified by the controlled deposition of thin layers containing appropriate functional groups and this research area is now a subject of widespread interest. The layer-by-layer (lbl) method involves depositing oppositely charged layers of polyelectrolytes onto the substrate material which are stabilized due to strong electrostatic forces between adjacent layers. This type of modification affords products that combine the properties of the original material with the superficial parameters of the new external layers. Through an appropriate selection of the deposited layers, the surface properties can be precisely controlled and readily adjusted in order to meet the requirements of the intended application. In the presented paper a variety of anionic (poly(acrylic acid)) and cationic (linear poly(ethylene imine), polymers were successfully deposited onto the polypropylene nonwoven using the lbl technique. The chemical structure of the surface before and after modification was confirmed by reflectance FTIR spectroscopy, volumetric analysis and selective dyeing tests. As a direct result of this work, new materials with greatly improved properties have been produced. For example, following a modification process significant changes in the electrostatic activity of a range of novel nanocomposite materials were observed. The deposition of polyelectrolyte nanolayers was found to strongly accelerate the loss of electrostatically generated charges and to increase considerably the thermal resistance properties of the modified fabric (the difference in T50% is over 20oC). From our results, a clear relationship between the type of polyelectrolyte layer deposited onto the flat fabric surface and the properties of the modified fabric was identified.

Keywords: Layer-by-layer technique, polypropylene nonwoven, surface modification, surface properties.

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774 The Construction of a Probiotic Lactic Acid Bacterium Expressing Acid-Resistant Phytase Enzyme

Authors: R. Majidzadeh Heravi, M. Sankian, H. Kermanshahi, M. R. Nassiri, A. Heravi Moussavi, S. A. Lari, A. R. Varasteh

Abstract:

The use of probiotics engineered to express specific enzymes has been the subject of considerable attention in poultry industry because of increased nutrient availability and reduced cost of enzyme supplementation. Phytase enzyme is commonly added to poultry feed to improve digestibility and availability of phosphorus from plant sources. To construct a probiotic with potential of phytate degradation, phytase gene (appA) from E. coli was cloned and transformed into two probiotic bacteria Lactobacillus salivarius and Lactococcus lactis. L. salivarous showed plasmid instability, unable to express the gene. The expression of appA gene in L. lactis was analyzed by detecting specific RNA and zymography assay. Phytase enzyme was isolated from cellular extracts of recombinant L. lactis, showing a 46 kDa band upon the SDS-PAGE analysis. Zymogram also confirmed the phytase activity of the 46 kDa band corresponding to the enzyme. An enzyme activity of 4.9U/ml was obtained in cell extracts of L. lactis. The growth of native and recombinant L. lactis was similar in the presence of two concentrations of ox bile.

Keywords: Lactobacillus salivarus, Lactococcus lactis, recombinant, phytase, poultry.

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773 Screening and Identification of Microorganisms – Potential Producers of Arachidonic Acid

Authors: A. V. Goncharova, T. A. Karpenyuk, Y. S. Tsurkan, R. U. Beisembaeva, A. M. Kalbaeva, T. D. Mukasheva, L. V. Ignatova

Abstract:

Microorganisms isolated from water and soil of Kazakhstan to identify potential high-effective producers of the arachidonic acid, exhibiting a wide range of physiological activity and having practical applications were screened. Based on the results of two independent tests (the test on the sensitivity of the growth processes of microorganisms to acetylsalicylic acid - an irreversible inhibitor of PGH-synthase involved in the metabolism of arachidonic acid and its derivatives, the test for inhibition of peroxidase activity of membrane-bounding fraction of PGH - synthase by acetylsalicylic acid) were selected microbial cultures which are potential highproducer of arachidonic acid. They are characterized by a stable strong growth in the laboratory conditions. Identification of microorganism cultures based on morphological, physiological, biochemical and molecular genetic characteristics was performed.

Keywords: Arachidonic acid, aspirin-sensitive culture, bacteria, producers, screening.

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772 Dextran/Poly(L-histidine) Graft Copolymer for pH-Responsive Drug Delivery

Authors: Dae Hwan Kang, Young-IL Jeong, Chung-Wook Chung

Abstract:

pH-sensitive drug targeting using nanoparticles for cancer chemotherapy have been spotlighted in recent decades. Graft copolymer composed of poly (L-histidine) (PHS) and dextran (DexPHS) was synthesized and pH-sensitive nanoparticles were fabricated for pH-responsive drug delivery of doxorubicin (DOX). Nanoparticles of DexPHS showed pH-sensitive changes in particle sizes and drug release behavior, i.e. particle sizes and drug release rate were increased at acidic pH, indicating that DexPHS nanoparticles have pH-sensitive drug delivery potentials. Antitumor activity of DOX-incorporated DexPHS nanoparticles were studied using CT26 colorectal carcinoma cells. Results indicated that fluorescence intensity was higher at acidic pH than basic pH. These results indicated that DexPHS nanoparticles have pH-responsive drug targeting.

Keywords: pH-sensitive polymer, nanoparticles, block copolymer, poly (L-histidine).

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771 Characterization of Penicillin V Acid and Its Related Compounds by HPLC

Authors: Bahdja Guerfi, N. Hadhoum, I. Azouz, M. Bendoumia, S. Bouafia, F. Z. Hadjadj Aoul

Abstract:

Background: 'Penicillin V' is a narrow, bactericidal antibiotic of the beta-lactam family of the naturally occurring penicillin group. It is limited to infections due to the germs defined as sensitive. The objective of this work was to identify and to characterize Penicillin V acid and its related compounds by High-performance liquid chromatography (HPLC). Methods: Firstly phenoxymethylpenicillin was identified by an infrared absorption. The organoleptic characteristics, pH, and determination of water content were also studied. The dosage of Penicillin V acid active substance and the determination of its related compounds were carried on waters HPLC, equipped with a UV detector at 254 nm and Discovery HS C18 column (250 mm X 4.6 mm X 5 µm) which is maintained at room temperature. The flow rate was about 1 ml per min. A mixture of water, acetonitrile and acetic acid (65:35:01) was used as mobile phase for phenoxyacetic acid ‘impurity B' and a mixture of water, acetonitrile and acetic acid (650:150:5.75) for the assay and 4-hydroxypenicillin V 'impurity D'. Results: The identification of Penicillin V acid active substance and the evaluation of its chemical quality showed conformity with USP 35th edition. The Penicillin V acid content in the raw material is equal to 1692.22 UI/mg. The percentage content of phenoxyacetic acid and 4-hydroxypenicillin V was respectively: 0.035% and 0.323%. Conclusion: Through these results, we can conclude that the Penicillin V acid active substance tested is of good physicochemical quality.

Keywords: Penicillin V acid, characterization, related substances, HPLC.

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770 Proteomic Analysis of Tumor Tissue after Treatment with Ascorbic Acid

Authors: Seyeon Park, Mi Jang

Abstract:

Tumor cells have an invasive and metastatic phenotype that is the main cause of death for cancer patients. Tumor establishment and penetration consists of a series of complex processes involving multiple changes in gene expression. In this study, intraperitoneal administration of a high concentration of ascorbic acid inhibited tumor establishment and decreased tumor mass in BALB/C mice implanted with S-180 sarcoma cancer cells. To identify proteins involved in the ascorbic acid-mediated inhibition of tumor progression, changes in the tumor proteome associated with ascorbic acid treatment of BALB/C mice implanted with S-180 were investigated using two-dimensional gel electrophoresis and mass spectrometry. Twenty protein spots were identified whose expression was different between control and ascorbic acid treatment groups.

Keywords: Ascorbic acid, Proteomic analysis, S-180 implantedBALB/C mouse

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769 Prediction of Kinematic Viscosity of Binary Mixture of Poly (Ethylene Glycol) in Water using Artificial Neural Networks

Authors: M. Mohagheghian, A. M. Ghaedi, A. Vafaei

Abstract:

An artificial neural network (ANN) model is presented for the prediction of kinematic viscosity of binary mixtures of poly (ethylene glycol) (PEG) in water as a function of temperature, number-average molecular weight and mass fraction. Kinematic viscosities data of aqueous solutions for PEG (0.55419×10-6 – 9.875×10-6 m2/s) were obtained from the literature for a wide range of temperatures (277.15 - 338.15 K), number-average molecular weight (200 -10000), and mass fraction (0.0 – 1.0). A three layer feed-forward artificial neural network was employed. This model predicts the kinematic viscosity with a mean square error (MSE) of 0.281 and the coefficient of determination (R2) of 0.983. The results show that the kinematic viscosity of binary mixture of PEG in water could be successfully predicted using an artificial neural network model.

Keywords: Artificial neural network, kinematic viscosity, poly ethylene glycol (PEG)

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768 Kinetic Study of Gluconic Acid Batch Fermentation by Aspergillus niger

Authors: Akbarningrum Fatmawati, Rudy Agustriyanto, Lindawati

Abstract:

Gluconic acid is one of interesting chemical products in industries such as detergents, leather, photographic, textile, and especially in food and pharmaceutical industries. Fermentation is an advantageous process to produce gluconic acid. Mathematical modeling is important in the design and operation of fermentation process. In fact, kinetic data must be available for modeling. The kinetic parameters of gluconic acid production by Aspergillus niger in batch culture was studied in this research at initial substrate concentration of 150, 200 and 250 g/l. The kinetic models used were logistic equation for growth, Luedeking-Piret equation for gluconic acid formation, and Luedeking-Piret-like equation for glucose consumption. The Kinetic parameters in the model were obtained by minimizing non linear least squares curve fitting.

Keywords: Aspergillus niger, fermentation, gluconic acid, kinetic.

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767 The Use of Acid-Aluminium Tolerant Bradyrhizobium japonicum Formula for

Authors: Nisa Rachmania Mubarik, Tedja Imas, Aris Tri Wahyudi , Triadiati , Suharyanto, Happy Widiastuti

Abstract:

Land with low pH soil spread widely in Indonesia can be used for soybean (Glycine max) cultivation, however the production is low. The use of acid tolerant soybean and acidaluminium tolerant nitrogen-fixing bacteria formula was an alternative way to increase soybean productivity on acid soils. Bradyrhizobium japonicum is one of the nitrogen fixing bacteria which can symbiose with soybean plants through root nodule formation. Most of the nitrogen source required by soybean plants can be provided by this symbiosis. This research was conducted to study the influence of acid-aluminium tolerant B. japonicum strain BJ 11 formula using peat as carrier on growth of Tanggamus and Anjasmoro cultivar soybean planted on acid soil fields (pH 5.0- 5.5). The results showed that the inoculant was able to increase the growth and production of soybean which were grown on fields acid soil at Sukadana (Lampung) and Tanah Laut (South Kalimantan), Indonesia.

Keywords: Bradyrhizobium japonicum, acid-aluminium tolerant mutant, Tanggamus cultivar soybean, acid soils

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766 Effects of Ophiocordyceps dipterigena BCC 2073 β-Glucan as a Prebiotic on the in vitro Growth of Probiotic and Pathogenic Bacteria

Authors: Wai Prathumpai, Pranee Rachtawee, Sutamat Khajeeram, Pariya Na Nakorn

Abstract:

The  β-glucan produced by Ophiocordyceps dipterigena BCC 2073 is a (1, 3)-β-D-glucan with highly branching O-6-linkedside chains that is resistant to acid hydrolysis (by hydrochloric acid and porcine pancreatic alpha-amylase). This β-glucan can be utilized as a prebiotic due to its advantageous structural and biological properties. The effects of using this β-glucan as the sole carbon source for the in vitro growth of two probiotic bacteria (L. acidophilus BCC 13938 and B. animalis ATCC 25527) were investigated. Compared with the effect of using 1% glucose or fructo-oligosaccharide (FOS) as the sole carbon source, using 1% β-glucan for this purpose showed that this prebiotic supported and stimulated the growth of both types of probiotic bacteria and induced them to produce the highest levels of metabolites during their growth. The highest levels of lactic and acetic acid, 10.04 g·L-1 and 2.82 g·L-1, respectively, were observed at 2 h of cultivation using glucose as the sole carbon source. Furthermore, the fermentation broth obtained using 1% β-glucan as the sole carbon source had greater antibacterial activity against selected pathogenic bacteria (B. subtilis TISTR 008, E. coli TISTR 780, and S. typhimurium TISTR 292) than did the broths prepared using glucose or FOS as the sole carbon source. The fermentation broth obtained by growing L. acidophilus BCC 13938 in the presence of β-glucan inhibited the growth of B. subtilis TISTR 008 by more than 70% and inhibited the growth of both S. typhimurium TISTR 292 and E. coli TISTR 780 by more than 90%. In conclusion, O. dipterigena BCC 2073 is a potential source of a β-glucan prebiotic that could be used for commercial production in the near future.

Keywords: β-glucan, Ophiocordyceps dipterigena, prebiotic, probiotic, antimicrobial.

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765 Effect of Different Salts on Pseudomonas taetrolens’ Ability to Lactobionic Acid Production

Authors: I. Sarenkova, I. Ciprovica, I. Cinkmanis

Abstract:

Lactobionic acid is a disaccharide formed from gluconic acid and galactose, and produced by oxidation of lactose. Productivity of lactobionic acid by microbial synthesis can be affected by various factors, and one of them is a presence of potassium, magnesium and manganese ions. In order to extend lactobionic acid production efficiency, it is necessary to increase the yield of lactobionic acid by optimising the fermentation conditions and available substrates for Pseudomonas taetrolens growth. The object of the research was to determinate the application of K2HPO4, MnSO4, MgSO4 × 7H2O salts in different concentration for effective lactose oxidation to lactobionic acid by Pseudomonas taetrolens. Pseudomonas taetrolens NCIB 9396 (NCTC, England) and Pseudomonas taetrolens DSM 21104 (DSMZ, Germany) were used for the study. The acid whey was used as the study object. The content of lactose in whey samples was determined using MilcoScanTM Mars (Foss, Denmark) and high performance liquid chromatography (Shimadzu LC 20 Prominence, Japan). The content of lactobionic acid in whey samples was determined using the high performance liquid chromatography. The impact of studied salts differs, Mn2+ and Mg2+ ions enhanced fermentation instead of K+ ions. Results approved that Mn2+ and Mg2+ ions are necessary for Pseudomonas taetrolens growth. The study results will help to improve the effectiveness of lactobionic acid production with Pseudomonas taetrolens NCIB 9396 and DSM 21104.

Keywords: lactobionic acid, lactose oxidation, Pseudomonas taetrolens, whey.

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764 Effect of Castration on CLA in Meat Goats

Authors: P. Paengkoum, T. Phonmun, S. Paengkoum

Abstract:

Twenty four male Thai native × Anglo-Nubian crossbred goats were randomly allocated to receive four treatments. The experiment was conducted for four months and slaughtered that the Longissimus dorsi muscle was collected for fatty acid analysis. The results conclude that either castrated method or ages had no significantly different on monounsaturated fatty acid (MUFA) (P>0.05) except erucic acid (C22:1n9). Interaction between castrated method and ages had significantly different in MUFA (P<0.01). Although the effect of castration method and age are not difference on fatty acid composition, it contributed to known that difference castration method and age (surgical and budizzo) no effect on accumulation fatty acid in meat goats.

Keywords: Castration, goat, CLA, meat.

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763 Weight Loss Degradation of Hybrid Blends LLDPE/Starch/PVA upon Exposure to UV Light and Soil Burial

Authors: M. Rahmah, Noor Zuhaira Abd Aziz, M. Mohd Muizz Fahimi, M. Farhan

Abstract:

Poly bag and mulch films for agricultural field caused pose environmental problem due to the non-degradable plastics wastes upon disposal. Thus, a degradable poly bag was designed with hybrid sago starch (SS) and polyvinyl alcohol (PVA). Two Different blended compositions of SS and PVA hybrid have been compounded. Then, the hybrids blended are mixed with linear line density polyethylene (LLDPE) resin to fabricate poly bag film through conventional film blowing process. Samples of LLDPE, SS and PVA hybrid film were exposed to UV light and soil burial. The weight losses were determined during degradation process. Hybrid film by degradation of starch was found to hydrolyze and hydroxyl groups decrease on esterification upon exposure to soil burial and uv radiation. It was found out that, the hybrid film for 60% of SS composition showed greatest degradation in soil and UV radiation.

Keywords: LLDPE, PVA, sago starch, degradation, soil burial, UV radiation.

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762 Treatment of Mycotic Dermatitis in Domestic Animals with Poly Herbal Drug

Authors: U. Umadevi, T. Umakanthan

Abstract:

Globally, mycotic dermatitis is very common but there is no single proven specific allopathic treatment regimen. In this study, domestic animals with skin diseases of different age and breed from geographically varied regions of Tamil Nadu state, India were employed. Most of them have had previous treatment with native and allopathic medicines without success. Clinically, the skin lesions were found to be mild to severe. The trial animals were treated with poly herbal formulation (ointment) prepared using the indigenous medicinal plants – viz Andrographis paniculata, Lawsonia inermis and Madhuca longifolia. Allopathic antifungal drugs and ointments, povidone iodine and curabless (Terbinafine HCl, Ofloxacin, Ornidazole, Clobetasol propionate) were used in control. Comparatively, trial animals were found to have lesser course of treatment time and higher recovery rate than control. In Ethnoveterinary, this combination was tried for the first time. This herbal formulation is economical and an alternative for skin diseases.

Keywords: Allopathic drugs, dermatitis, domestic animals, poly herbal formulation.

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761 Evaluation of Corrosion Caused by Biogenic Sulfuric Acid (BSA) on the Concrete Structures of Sewerage Systems (Chemical Tests)

Authors: M. Cortés, E. Vera, O. Rojas

Abstract:

The research studies of the kinetics of the corrosion process that attacks concrete and occurs within sewerage systems agree on the amount of variables that interfere in the process. This study aims to check the impact of the pH levels of the corrosive environment and the concrete surface, the concentrations of chemical sulfuric acid, and in turn, measure the resistance of concrete to this attack under controlled laboratory conditions; it also aims to contribute to the development of further research related to the topic, in order to compare the impact of biogenic sulfuric acid and chemical sulfuric acid involvement on concrete structures, especially in scenarios such as sewerage systems.

Keywords: Acid Sulfuric, concrete, corrosion.

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