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Synthesis Of Fisetin Glycosides By Cyclodextrin Glycosyltransferase From Paenibacillus Sp. Rb01, Nattawadee Lorthongpanich
Synthesis Of Fisetin Glycosides By Cyclodextrin Glycosyltransferase From Paenibacillus Sp. Rb01, Nattawadee Lorthongpanich
Chulalongkorn University Theses and Dissertations (Chula ETD)
Fisetin is a flavonoid which was widely exerted in pharmacological industries. However, fisetin has low water solubility and unstable in aqueous solution. So the uses of fisetin have been limited. The purpose of this study was to increase water solubility of fisetin by transglycosylation reaction using cyclodextrin glycosyltransferase (CGTase) from Paenibacillus sp. RB01. The reaction had to perform in co-organic solvent system and DMSO at 40% (v/v) was proved to be the most suitable co-organic solvent since it provided the high enzyme stability and high production yield. Moreover, the types of glycosyl donor were also determined and β-cyclodextrin was found …
Isolation And Characterization Of Triclocarban Degrading Bacteria As Plant Growth Promoter, Merry Krisdawati Sipahutar
Isolation And Characterization Of Triclocarban Degrading Bacteria As Plant Growth Promoter, Merry Krisdawati Sipahutar
Chulalongkorn University Theses and Dissertations (Chula ETD)
Triclocarban (TCC) is a widely used as antimicrobial agent in household products. High usage volume of TCC results in its accumulation in sludge and lead to contamination in environments. Application of biosolid in agricultural activities leads to contamination of TCC in agricultural areas. So. development of bioremediation technique for TCC is necessary to maintain quality of agricultural ecosystem. For that purpose, this research isolated 5 soil bacteria capable of TCC degradation and with plant-growth promoting (PGP) activities including Ochrobactrum sp. MC22, Ochrobactrum sp. MC35, Sphingobacterium sp. MC43, Pseudomonas sp. MS45, and Pseudomonas fluorescens MC46. Among them, Ochrobactrum sp. MC22 and …
Prevalence And Molacular Genetic Analysis Of Human Respiratory Syncytial Virus And Enterovirus 68 Among Children With Acute Lower Respiratory Tract Infection In Thailand, I-Lada Thongpan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Respiratory syncytial virus (RSV) causes acute lower respiratory tract infection in infants and young children worldwide. A clear description of local RSV molecular epidemiology, evolution, and transmission requires detailed sequence data and can inform new strategies for virus control and vaccine development. To investigate the RSV burden in Thailand over six consecutive years (January 2012 to December 2017). There were two different methods to detect RSV in the present study. First, we screened 3306 samples obtained from children ≤5 years old with acute respiratory tract infection using semi-nested reverse-transcription polymerase chain reaction (RT-PCR) during January 2012 to December 2015. Second, …
Pathomechanism Of X-Linked Osteogenesis Imperfecta, Siraprapa Tongkobpetch
Pathomechanism Of X-Linked Osteogenesis Imperfecta, Siraprapa Tongkobpetch
Chulalongkorn University Theses and Dissertations (Chula ETD)
Osteogenesis imperfecta (OI) or brittle bone disease is a genetic disorder characterized by deformities of bones and multiple bone fractures. We identified a new causative gene, MBTPS2, in two unrelated patients with OI inherited in X-linked pattern (X-OI). MBTPS2 or site-2 protease (S2P) is a protease that cleaves the transmembrane proteins to activate them acting as transcription factors. To determine pathomechanism of X-OI caused by MBTPS2 mutations, S2P functions were investigated. RNA and protein of S2P were stable. Instead, the defective S2P decreases its cleavage activities. ATF6 and CREB3L1 are target proteins of S2P. We demonstrated decreased a transcriptional activity …
Intracellular Trafficking Of Different Shaped Oxidized Carbon Nanoparticles, Banphot Jiangchareon
Intracellular Trafficking Of Different Shaped Oxidized Carbon Nanoparticles, Banphot Jiangchareon
Chulalongkorn University Theses and Dissertations (Chula ETD)
Oxidized carbon nanospheres (OCSs) and graphene oxide sheets (GOShs) were prepared by oxidation of graphite. Oxidized carbon nanotubes (OCTs) was synthesized from single-walled carbon nanotubes. All three shapes of oxidized carbon nanoparticles (OCNs) were used for investigation of their intracellular trafficking in human embryonic kidney cells (HEK293T), mouse macrophage cells (RAW264.7) and human liver cancer cells (HepG2). The results revealed all three shapes of OCNs were internalized into through HEK293T and RAW264.7 cells without endosomal trapping, including localization of all the three OCNs in HEK293T's lysosome. In case of RAW264.7 cells, OCTs and GOShs were localized in lysosomes, only OCSs …
Development Of Molecular Technique For Risk Assessment And Risk Management Of Listeria Monocytogenes And L. Innocua In Frozen Cooked Chicken Plant, Chirapiphat Phraephaisarn
Development Of Molecular Technique For Risk Assessment And Risk Management Of Listeria Monocytogenes And L. Innocua In Frozen Cooked Chicken Plant, Chirapiphat Phraephaisarn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Thailand is one of the largest cooked chicken meat exporting country in the world. Unfortunately, these products can be contaminated with L. monocytogenes causes the disease Listeriosis which carries a fatality rate of 30 to 40 percent. Therefore, the various importing countries including Japan and the European countries require a zero tolerance for L. monocytogenes in the cooked chicken products. Besides, all Listeria spp. occurrence, and not only L. monocytogenes, in these products is also unacceptable to the importers. Rejection of Listeria contaminated product can reach over 5 to 20 million baht per factory per year. Hence, the aim of …
Separation And Purification Of Lactic Acid From Fermentation Broth By Reverse Osmosis, Natnirin Phanthumchinda
Separation And Purification Of Lactic Acid From Fermentation Broth By Reverse Osmosis, Natnirin Phanthumchinda
Chulalongkorn University Theses and Dissertations (Chula ETD)
Brackish water reverse osmosis (BWRO) and seawater reverse osmosis (SWRO) membranes were used in the 2-stage reverse osmosis (RO) unit to recover, pre-purify, and pre-concentrate lactic acid. Calcium lactate (CaLAC), sodium lactate (NaLAC), and ammonium lactate (NH4LAC) were used as model feed solutions. The operating pressure showed a pronounced effect on lactate passage through the first BWRO unit, and the Donnan exclusion effect and hydrogen bonding were responsible for cation rejection. Calcium ions were rejected at the BWRO unit because of low diffusion rate and charge interaction at the surface. However, monovalent ions formed hydrogen bonds with the carbonyl group …
Antibacterial Agents From Dracaena Cochinchinensis (Lour.) S.C.Chen And Eleutherine Americana (Aubl.) Merr. Ex K. Heyne, Ritbey Ruga
Chulalongkorn University Theses and Dissertations (Chula ETD)
Fifteen compounds including two new anthraquinones (118-119), two naturally occurring new compounds (116-117) and eleven known compounds were successfully isolated from the CH2Cl2 extracts of Dracaena cochinchinensis and Eleutherine americana i.e. dihydrochalcones (5 and 23), pterostilbene (27), homoisoflavanones (15 and 82-84), naphthalenes (85 and 116), pyranonaphthoquinone (86) and anthraquinones (99-100 and 117-119). Among isolated compounds, (+)-eleutherin (86) was the most potent antibacterial agent against Propionibacterium acnes KCCM 41747, Staphylococcus aureus ATCC 25923, Streptococcus sobrinus KCCM 11898, Streptococcus mutans ATCC 25175 and Salmonella typhi ATCC 422 with inhibition zones of 14.7 to 18.0 mm and MIC values of 0.24 to 7.8 …
Adaptation Of Terrilactibacillus Laevilacticus Sk5-6 For Growth And D-Lactic Acid Production In A Low Yeast Extract Concentration Medium, Srettapat Limsampancharoen
Adaptation Of Terrilactibacillus Laevilacticus Sk5-6 For Growth And D-Lactic Acid Production In A Low Yeast Extract Concentration Medium, Srettapat Limsampancharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
Lactic acid has been extensively used in food, personal care, and pharmaceutical products. Besides, lactic acid can be used as the sole feedstock in the synthesis of polylactic acid (PLA), the biodegradable plastic. The demand of the bioplastics including PLA has been increased due to the environmental impact of petroleum based plastic; therefore, this expedited the market demand of lactic acid. It should be noted that the polymer grade lactic acid is unlike those commercially available products for food and pharmaceutical applications. The high purity of stereoisomer either D-lactate or L-lactate is mandatory in PLA polymerization. In addition, the production …
Bioactive Compounds From Songkhla Province Mangrove-Derived Endophytic Fungi And From Heart-Leaved Moonseed Tinospora Baenzigeri Forman, Sujitra Hanthanong
Bioactive Compounds From Songkhla Province Mangrove-Derived Endophytic Fungi And From Heart-Leaved Moonseed Tinospora Baenzigeri Forman, Sujitra Hanthanong
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study has evaluated biological activities of isolated compounds from Tinospora baenzigeri stems collecting from two different areas, and from mangrove-derived endophytic fungi isolated from trees inhabiting in Songkhla province. Four new rearranged clerodane-type diterpenes (66-69), one new glycoside (70), and six known compounds (61, 71-75), were extracted from plant obtained from local market in Bangkok. Twelve compounds including a new rearranged clerodane-type diterpene (76), a new rearranged clerodane glycoside (77), five known compounds (44, 78-81), and five compounds counting 61, 66, 70 and 74-75 were obtained from plant collected in Bueng Kan Province. Structures of new compounds 66-69 and …
Increasing Viability Of Probiotic Bacteria Co-Encapsulated With Prebiotic For Disease Resistance In White Shrimp Litopenaeus Vannamei, Suppharada Jantarathin
Increasing Viability Of Probiotic Bacteria Co-Encapsulated With Prebiotic For Disease Resistance In White Shrimp Litopenaeus Vannamei, Suppharada Jantarathin
Chulalongkorn University Theses and Dissertations (Chula ETD)
The main problem of probiotics is the low survival of these microorganisms in food products and sensitive to harsh conditions during food processing, storage and in the gastrointestinal tract. The suitable technology for protecting probiotics to maintain the high number of probiotic cells in product and survived within the host which is microencapsulation technique. The aim of this work was to investigate the effect of prebiotic which is inulin or Jerusalem artichoke on the survival of encapsulated Lactobacillus acidophilus TISTR 1338 within alginate matrix and double-coated with chitosan after freeze-drying process and heat processing at 70°C for 60 min. Furthermore, …
Optimization Of Preparation Protein Hydrolysate By Protease G6 Using Response Surface Methodology And Free Radical Scavenging Activities From Feather Meal, Waleeporn Pibulpol
Optimization Of Preparation Protein Hydrolysate By Protease G6 Using Response Surface Methodology And Free Radical Scavenging Activities From Feather Meal, Waleeporn Pibulpol
Chulalongkorn University Theses and Dissertations (Chula ETD)
The aim of this research was to study the optimal condition for chicken feather meal protein hydrolysate production using a microbial protease, Protease G6. The experimentation was conducted using Central Composite Design (CCD) and Response Surface Methodology (RSM). The three independent variables including temperature (°C), time and enzyme-substrate ratio were studied. Optimization process for obtaining high yield of chicken feather meal protein hydrolysate was performed using response surface methodology (RSM) by optimizing a combination of three independent variables namely, temperature (41.59 – 58.41°C), time (0:38 - 7:21 h) and enzyme-substrate ratio (0.8 – 9.2) with degree of hydrolysis (DH) as …
Dehydration And Oxidative Dehydrogenation Of Ethanol Over Sba-15 Based Catalysts Prepared By Sol-Gel And Hydrothermal Methods, Chaowat Autthanit
Dehydration And Oxidative Dehydrogenation Of Ethanol Over Sba-15 Based Catalysts Prepared By Sol-Gel And Hydrothermal Methods, Chaowat Autthanit
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this present study, characteristics and catalytic properties of zirconium (Zr) and bimetal (Zr and La) containing in SBA-15 catalysts and different VOx/SBA-15 catalysts were determined and well related. The study was divided into three parts. Regarding to the first part, zirconium (Zr) and bimetal (Zr and La) containing in SBA-15 synthesized by sol-gel and hydrothermal methods were compared. The results showed that the incorporation of Zr and bimetal (Zr and La) had an effect on the textural properties of both synthesized SBA-15 catalysts. Surface acidity in the SBA-15 suggests new active sites, especially Brønsted acid type. In the second …
Performance Comparison Of Different Membrane Micro-Channel Reactors For Methanol Production From Biogas And Hydrogen, Khunnawat Ountaksinkul
Performance Comparison Of Different Membrane Micro-Channel Reactors For Methanol Production From Biogas And Hydrogen, Khunnawat Ountaksinkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
In order to integrate simultaneous methanol production with biogas upgrading in a single unit, the computational fluid dynamics (CFD) models of a triple pipe tubular membrane reactor (TMR) and a planar membrane micro-structured reactor (MMR) were established via COMSOL Multiphysics 5.3a and compared their effect on reactor performance under predetermined condition. For the conceptual design of these reactors, the channel inside the reactors can be divided into three parts; biogas channel (BC), reaction channel (RC) and sweep gas channel (SC). The CO2 in biogas entering into BC is separated through CO2 selective membrane to produce methanol inside RC. Afterwards, water …
Effects Of Polyol Molecular Weights On Thermally Reversible Light Scattering Behaviors Of Benzoxazine-Urethane Copolymers, Kittipon Bunyanuwat
Effects Of Polyol Molecular Weights On Thermally Reversible Light Scattering Behaviors Of Benzoxazine-Urethane Copolymers, Kittipon Bunyanuwat
Chulalongkorn University Theses and Dissertations (Chula ETD)
The thermally reversible light scattering behaviors of benzoxazine-urethane copolymer was investigated in this work. Benzoxazine monomers (BA-a) were synthesized by the solventless synthesis technique from bisphenol-A, para-formaldehyde, and aniline with the molar ratio of 1:4:2, respectively. Urethane prepolymer was prepared by reacting poly(propylene glycol) (Mw = 1000, 2000, or 3000 g/mol) with toluene diisocyanate (TDI) at the molar ratio of 1:2 under a nitrogen atmosphere. The obtained urethane prepolymer (PU) was labelled as PU1K, PU2K, and PU3K with respect to the molecular weights of polyether polyol employed in the preparation step. Urethane prepolymer and benzoxazine monomers were crosslinked during the …
Characteristics And Catalytic Properties Of Agli/Sio2 Catalysts On Different Silica Supports For Oxidative Dehydrogenation Of Ethanol To Acetaldehyde, Narawich Mukda
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work focuses on investigation of the oxidative dehydrogenation and non-oxidative dehydrogenation of ethanol over AgLi/SiO2 catalysts to produce acetaldehyde by having three different types of silica support, spherical silica particle (small particle size; SPS), medium silica particle size (MPS), and large silica particle size (LPS). The spherical silica particle (SSP) was synthesized using the sol-gel method, whereas SiO2 (MPS) and SiO2 (LPS) were obtained from commercial suppliers. AgLi/SiO2 catalysts were prepared by incipient wetness co-impregnation method. The physicochemical properties of catalysts were analyzed by using several technique such as X-ray diffraction (XRD), N2-physisorption, SEM-EDX, UV-visible spectroscopy, H2-TPR. Moreover, the …
Hydrogen Production From Biogas By The Combined Process Of Chemical Looping Water Splitting And Sorption Enhanced Reforming Process: Process Analysis And Design, Natthaporn Saithong
Hydrogen Production From Biogas By The Combined Process Of Chemical Looping Water Splitting And Sorption Enhanced Reforming Process: Process Analysis And Design, Natthaporn Saithong
Chulalongkorn University Theses and Dissertations (Chula ETD)
The integrated sorption-enhanced chemical looping reforming and water splitting (SECLR-WS) process was proposed for hydrogen (H2) production from biogas using iron oxide as the oxygen carrier and calcium oxide (CaO) as a carbon dioxide (CO2) adsorbent. The simulation of the SECLR-WS process was based on a thermodynamic approach and was performed using an Aspen Plus simulator. The sensitivity results showed that the H2 yield (mole of H2/mole of CH4), H2 purity in the fuel reactor (FR), and CH4 conversion could be improved by increasing the steam feed to the FR to CH4 (SFR/CH4) and CaO to CH4 (CaO/CH4) molar ratios. …
Modification Of Titanium Dioxide With Nitrogen, Silicon, And Carbon For Visible Light Photocatalysis, Rachan Klaysri
Modification Of Titanium Dioxide With Nitrogen, Silicon, And Carbon For Visible Light Photocatalysis, Rachan Klaysri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Titanium dioxide and nitrogen-silicon-codoped titanium dioxide were prepared by two different ways. The first method was prepared by using nitrogen as a nitrogen source and silicon-containing chemical as a silicon source via solvothermal- and sol-gel-made photocatalysts. The nitrogen-silicon-codoped titanium dioxide showed the highest photocatalytic activity under both UV and visible light irradiation. The addition of silicon resulted in the formation of partial monolayer of silicon on titanium dioxide and an increase of the anatase phase stability. The annealing atmosphere affected the distribution concentration of surface and interface species such as surface oxygen and Ti3+ sites, thus improving photocatalytic activity. Moreover, …
The Effect Of Adsorption On Photocatalytic Degradation Of Phenyl Urea Herbicides On Zinc Oxide, Sutaporn Meephon
The Effect Of Adsorption On Photocatalytic Degradation Of Phenyl Urea Herbicides On Zinc Oxide, Sutaporn Meephon
Chulalongkorn University Theses and Dissertations (Chula ETD)
The effect of adsorption on photocatalytic degradation was studied by using zinc oxide with different morphologies and exposed surfaces as the photocatalyst. Polar zinc-terminated surface and polar oxygen-terminated surface are dominating planes on the top and bottom of a crystal of ZnO conventional particles, while non-polar surface is the main plane on the side of ZnO nanorods. These surfaces affect the adsorption behavior of phenylurea herbicides, i.e. diuron, linuron and 3,4-dichloroaniline. Consequently, they cause the difference in photocatalytic degradation rate and intermediate products formed during the degradation. The adsorption capacity of ZnO conventional particles is about twice as high as …
Performance Comparison Of Multifunctional Reactors For Biodiesel Production From Transesterification Of Palm Oil, Tanutporn Laosuttiwong
Performance Comparison Of Multifunctional Reactors For Biodiesel Production From Transesterification Of Palm Oil, Tanutporn Laosuttiwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Biodiesel is classified as a qualified alternative energy that can be used for diesel engine. It is produced via transesterification of vegetable oil with alcohol in presence of homogeneous or heterogeneous catalyst. However, oil and alcohol are not totally miscible leading to slow reaction rate. Multifunctional reactors, especially cavitational reactors, are proposed to overcome this issue. The cavitational reactors include ultrasonic reactor and homogenizer reactor. In this work, ultrasonic reactor, homogenizer reactor and conventional magnetic stirred reactor were used to investigate and compare biodiesel yield and the efficiency in terms of biodiesel yield based on the energy consumption at different …
Nanomaterial Sensors For Selective Detection Of Biothiol Compounds, Chiraporn Chaicham
Nanomaterial Sensors For Selective Detection Of Biothiol Compounds, Chiraporn Chaicham
Chulalongkorn University Theses and Dissertations (Chula ETD)
Novel nanomaterial sensors have been designed two different strategies of sensing approach. The first sensing system, the aggregation nanomicelles (TSC and TSD) were synthesized for GSH sensing based on disulfide-cleavaged trigger in the micelle. The result showed a large quenching fluorescent intensity around 587 nm and 528 nm corresponding to TSC and TSD, respectively, upon the addition of GSH in 2.5% DMSO/PBS at pH 6. Additionally, the benefit of TSD is utility for the distance-based fluorescence detection of 3D paper analytical device (3D-µPAD) for the detection of GSH. Apart from GQDs sensors base, we demonstrated the utility and board applicability …
Synthesis And Optical Properties Of Pyrrolidinyl Peptide Nucleic Acid Carrying Fluorescence Nucleobases, Duangrat Nim-Anussornkul
Synthesis And Optical Properties Of Pyrrolidinyl Peptide Nucleic Acid Carrying Fluorescence Nucleobases, Duangrat Nim-Anussornkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Pyrrolidinyl peptide nucleic acid bearing D-prolyl-2-aminocyclopentanecarboxylic acid backbone (acpcPNA) is a nucleic acid mimic that shows superior binding affinity, stability and specificity to complementary DNA than the original PNA. This research focuses on the development of hybridization responsive fluorescence acpcPNA probes bearing fluorescent nucleobases that exhibit fluorescence increase upon hybridization to a specific nucleobase in the DNA target. The acpcPNA carrying the fluorescent nucleobases were synthesized via two different approaches, namely 1) pre-synthesized fluorescence PNA monomer as a building block that was subsequently incorporated into the PNA by solid phase synthesis and 2) post-synthetic modification of acpcPNA carrying a reactive …
Selective Esterification Of Glycerol With Oleic Acid Using Tungstophosphoric Acid Supported On Functionalized Mesoporous Silica, Kullatida Ratchadapiban
Selective Esterification Of Glycerol With Oleic Acid Using Tungstophosphoric Acid Supported On Functionalized Mesoporous Silica, Kullatida Ratchadapiban
Chulalongkorn University Theses and Dissertations (Chula ETD)
A series of protonated amine-functionalized SBA-15 materials was successfully prepared. Each sample of mesoporous SBA-15 was first functionalized with each of the three types of amino-organosilanes: APTES (N), AAPTMS (NN), and DETTMS (NNN). Each of the resulting materials was then protonated with Keggin-type tungstophosphoric acid (HPW) at two different concentrations: 20 wt.% (H20) and 40 wt.% (H40). The six types of materials obtained were labelled as S-N1-H20, S-N1-H40, S-NN1-H20, S-NN1-H40, S-NNN1-H20, and S-NNN1-H40. The materials were fully characterized by XRD, N2 adsorption-desorption, FT-IR, SEM/EDX, TEM, and elemental analysis. The characterization results show that the synthesized materials exhibited highly ordered hexagonal …
Colorimetric Detection Of Cyanide Ions Using Complex Formation And Ctab-Coated Silica, Patita Salee
Colorimetric Detection Of Cyanide Ions Using Complex Formation And Ctab-Coated Silica, Patita Salee
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research presents a new colorimetric method of cyanide detection in solution and water samples based on the extraction of dicyano-bis-(1,10-phenanthroline)-iron(II) complex onto CTAB-coated silica. The complex was formed at pH 10 by using phosphate buffer via the complex formation between tris-(1,10-phenanthroline)-Iron(II) (ferroin) with cyanide ions in CTAB media. When the complex was extracted onto CTAB-coated silica, it resulted in a color change of the material from pale yellow to purple. The changing of color corresponded to cyanide concentration which could be observed by naked-eyes and the color intensity was determined by Image J. The effects of various parameters were …
Fluoride Encapsulation In Calcium Matrix, Piyada Dissara
Fluoride Encapsulation In Calcium Matrix, Piyada Dissara
Chulalongkorn University Theses and Dissertations (Chula ETD)
Fluoride ion (F-) is an important ingredient in a toothpaste. It protects caries by reacting with hydroxyapatite [Ca10(PO)4(OH)2] in tooth enamel to form insoluble fluorapatite [Ca10(PO)4(F)2]. Unfortunately, F- also easily interacts with calcium species in a toothpaste, and then it is deactivated. In this work, we focus on the encapsulation of F- in a shellac bead by using a simple extrusion method. To construct shellac beads, an aqueous solution of F- is injected into an ethanolic solution of shellac. The shellac beads are formed due to insolubility of shellac in water. Then, the beads are transferred into DI water for …
Ferrocene-Bearing Tea Polyphenol Particles As Anticancer Drug Carriers, Punnawich Phaiyarin
Ferrocene-Bearing Tea Polyphenol Particles As Anticancer Drug Carriers, Punnawich Phaiyarin
Chulalongkorn University Theses and Dissertations (Chula ETD)
Ferrocene is a redox moiety that can be positively charged upon being oxidized. Thus, it is possible to use this moiety to make a polymer platform that is redox responsive regarding their water solubility. Here we prepared polymerized EGCG nanoparticles (pEGCG) and polymerized EGCG gum (pEGCG-gum) from tea polyphenol EGCG. Ferrocene was grafted onto the polymerized tea polyphenol and the obtained polymers were allowed to self-assemble into water-insoluble and indispersible sub-micron particles. The water-insoluble ferrocene-bearing particles became water-dispersible particles with nanometer sizes upon being oxidized by hydrogen peroxide. The oxidized particles, Fc-pEG-gum can inhibit growth of HepG2 liver cancer cells …
Synthesis And Supramolecular Polymerization Of Peptide Nucleic Acid-Containing Monomer, Ruttiyakorn Donthongkwa
Synthesis And Supramolecular Polymerization Of Peptide Nucleic Acid-Containing Monomer, Ruttiyakorn Donthongkwa
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nucleobase-induced self-assembly interaction, have gained much attention as potential non-covalent driving force for generating interesting assembled structures. Pyrrolidinyl peptide nucleic acid (PNA), with (2′R,4′R)-prolyl/(1S,2S)-2-aminocyclopentanecarboxylic acid backbone (acpcPNA) has shown the recognition with complementary nucleic acids following Watson-Crick base rules. Another PNA system having different stereochemistry on proline ring with a backbone of (2′R,4′S)-prolyl/(1S,2S)-2-aminocyclopentanecarboxylic acid backbone (epi-acpcPNA) can undergo self-pairing. Here in this work, both acpcPNA- and epi-acpcPNA-functionalized monomers consisting of two PNA segments joined together by a flexible polyethylene glycol linker were prepared on solid support, purified by high performance liquid chromatography (HPLC) and characterized by MALDI-TOF mass spectrometry. The …
Bioactive Compounds From Lichens And Mycobionts In Trypetheliaceae Family, Suekanya Jarupinthusophon
Bioactive Compounds From Lichens And Mycobionts In Trypetheliaceae Family, Suekanya Jarupinthusophon
Chulalongkorn University Theses and Dissertations (Chula ETD)
Chemical constituents of two lichens Marcelaria cumingii and Trypethelium subeluteriae, and four cultured mycobionts from M. cumingii, T. platystomum, T. eluteriae and Trypethelium sp. (Trypetheliaceae) were explored. Their secondary metabolites were structurally elucidated by spectroscopic methods as xanthones, anthraquinones, naphthoquinones and phenalenones. Lichexanthone, parietin, xanthorin and emodin were disclosed as constituents of lichens M. cumingii. Whereas, two anthraquinones: parietin and emodin could be isolated from T. subeluteriae together with another anthraquinone, haematommone. The chemical compositions of four cultured mycobionts were found to totally differ from those from lichen. The phenalenone bipolaride C was derived from T. platystomum while two 1,2-naphthoquinones, …
Composite Fiber Of Poly(3,4-Ethylenedioxythiophene) And Derivative For Electrochemical Applications, Thanarath Pisuchpen
Composite Fiber Of Poly(3,4-Ethylenedioxythiophene) And Derivative For Electrochemical Applications, Thanarath Pisuchpen
Chulalongkorn University Theses and Dissertations (Chula ETD)
Poly(3,4-ethylenedioxythiophene) (PEDOT) is a conducting polymer that has many advantages including high conductivity, high transparency, and good stability. Despite its advantages, its insolubility and lack of active groups for further functionalization remain the major obstacles for its applications. In this work, polymer/PEDOT composite fibers were fabricated using solid state polymerization of 2,5-dibromo-3,4-ethylenedioxythiophene (DBEDOT) and its derivative containing carboxylic acid (DBEDOT-C4-COOH) in combination with electrospinning technique to ensure good dispersion of PEDOT in polymer matrix. The well-dispersed electrospun PEDOT/polymer composite the fiber mats were used to modify the screen-printed carbon electrode as testing models. The PEDOT/poly(vinyl alcohol) (PVA) composite fiber fabricated …
Design And Synthesis Of Selenium Nanoparticles To Overcome Multiple Drug Resistance Of Cancer Cells, Urarika Luesakul
Design And Synthesis Of Selenium Nanoparticles To Overcome Multiple Drug Resistance Of Cancer Cells, Urarika Luesakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
The objective of this research is to synthesize selenium nanoparticles (SeNPs) stabilized by chitosan as a drug carrier for delivery doxorubicin to overcome drug-resistant in cancer cells. One important mechanism of multidrug resistance (MDR) includes decreased drug influx and increased drug efflux, leading to insufficient drug concentration to kill cancer cells. Therefore, to overcome MDR by increasing cellular uptake, the surface of SeNP was functionalized to provide 3 structural features: (i) a positive charge to improve their solubility, (ii) gallic acid, a hydrophobic molecule to enhance biocompatibility and (iii) folic acid, a targeting molecule to target cancer cells and enhance …