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Meenakshisundaram S, Bangalore Kantharajanna S, Hawaldar SV, Subbaraj R. Eagle Syndrome: An Unusual Cause of Axial Neck Pain: A Case Report. JBJS Case Connect 2024; 14:01709767-202403000-00014. [PMID: 38241428 DOI: 10.2106/jbjs.cc.23.00490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2024]
Abstract
CASE A 42-year-old woman presented with left-sided axial neck pain with radiation behind left ear of 3 months unresponsive to conservative treatment. As clinical examination revealed tenderness anterior to the mastoid process, she was referred to an otolaryngologist. Computed tomography showed an elongated left styloid process. Diagnostic local anesthetic infiltration provided complete pain relief confirming the diagnosis of Eagle syndrome (ES) after which a transoral excision of the left styloid process was performed. She was asymptomatic till the final follow-up of 15 months. CONCLUSION ES should be considered in differential diagnosis of axial neck pain radiating to ear, and excision of the styloid process in resistant cases provides complete pain relief.
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Affiliation(s)
- Subbiah Meenakshisundaram
- Department of Spine Surgery, Velammal Medical College Hospital and Research Institute, Madurai, India
| | | | - Sangamesh V Hawaldar
- Department of Orthopaedics & Spine Surgery, Velammal Medical College Hospital and Research Institute, Madurai, India
| | - Rajavel Subbaraj
- Department of Otorhinolaryngology, Velammal Medical College Hospital and Research Institute, Madurai, India
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Sivaraman S, Markkandan R, Pandiarajan K, Meenakshisundaram S. Hydrogen-bonded structure and optical nonlinearities in the proton-transfer complex of 8-hydroxy-5-nitroquinoline with ρ-toluenesulfonic acid. Struct Chem 2023. [DOI: 10.1007/s11224-023-02123-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Sivaraman S, Balakrishnan C, Suppuraj P, Meenakshisundaram S. Synthesis, structure, Hirshfeld surface analysis, and computational studies of 2-amino-5-nitropyridine-2,4-dinitrophenol cocrystal. Struct Chem 2022. [DOI: 10.1007/s11224-022-02087-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Meenakshisundaram S, Fayeulle A, Leonard E, Ceballos C, Pauss A. Fiber degradation and carbohydrate production by combined biological and chemical/physicochemical pretreatment methods of lignocellulosic biomass - A review. Bioresour Technol 2021; 331:125053. [PMID: 33827779 DOI: 10.1016/j.biortech.2021.125053] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 05/10/2023]
Abstract
Sustainable biorefinery concepts based on lignocellulosic biomass are gaining worldwide research interest because of their inexpensiveness and abundance. The recalcitrance of lignocellulosic biomass poses a major hindrance to enhance biofuel production. Therefore, a pretreatment step is critical to prepare the substrates for the downstream process. Combining pretreatment steps help to lower the severity of the drawbacks of a single pretreatment step. This paper systematically reviews the combined biological and chemical/physicochemical pretreatment based on fiber degradation and sugar yield. An energy-efficient biological pretreatment method combined with a chemical pretreatment that accelerates the pretreatment times has been seen to be efficient for fiber degradation and sugar yields. However, fungal species, culture conditions, biomass type, the severity of chemical pretreatment and the order of sequential pretreatment influences the relative component contents and sugar yield. Even the same biomass from different sources undergoing similar pretreatment conditions could result in a varying amount of digestibility.
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Affiliation(s)
- S Meenakshisundaram
- Université de technologie de Compiègne, ESCOM, TIMR (Integrated Transformations of Renewable Matter), Centre de recherche Royallieu - CS 60 319, F-60 203 Compiègne Cedex, France
| | - A Fayeulle
- Université de technologie de Compiègne, ESCOM, TIMR (Integrated Transformations of Renewable Matter), Centre de recherche Royallieu - CS 60 319, F-60 203 Compiègne Cedex, France
| | - E Leonard
- Université de technologie de Compiègne, ESCOM, TIMR (Integrated Transformations of Renewable Matter), Centre de recherche Royallieu - CS 60 319, F-60 203 Compiègne Cedex, France
| | - C Ceballos
- Université de technologie de Compiègne, ESCOM, TIMR (Integrated Transformations of Renewable Matter), Centre de recherche Royallieu - CS 60 319, F-60 203 Compiègne Cedex, France
| | - A Pauss
- Université de technologie de Compiègne, ESCOM, TIMR (Integrated Transformations of Renewable Matter), Centre de recherche Royallieu - CS 60 319, F-60 203 Compiègne Cedex, France
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Abstract
Ligation to metal centre does inhibit aniline oxidation with HOOSO3- in the presence of Ru(III).
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Affiliation(s)
| | - V. Sathiyendiran
- Department of Chemistry, Annamalai University, Annamalainagar - 608002, India
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Meenakshisundaram S, Gopalakrishnan M, Nagarajan S, Sarathi N, Sumathi P. Kinetics and mechanism of the oxidation of alkenes by chromium(VI) in the presence of complexing agents. Journal of Chemical Research 2019. [DOI: 10.3184/0308234054497173] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The catalytic activities of 2,2′-bipyridyl (bipy) and oxalic acid (Oxa) in the HCrO4– oxidation of some substituted trans-cinnamic acids have been investigated in acidic solutions. The Cr(VI)–bipy and Cr(VI)–Oxa complexes are believed to be the probable reactive electrophiles in this redox process. The kinetic data reveal that electron-releasing groups enhance the reactivity to a significant extent while the electron-withdrawing ones reduce the rate marginally. It appears that the mechanism of bipy/Oxa catalysed chromium(VI) oxidation of unsaturated systems to the corresponding cleavage products involves an electrophilic attack of the reactive complex at the C–C double bond. The formation of a ternary complex as an intermediate is envisaged to describe the redox process. In this paper, we also report on the kinetic form of the oxidation of trans-stilbene to methyl 3-hydroxy-2,3-diphenylpropanoate. The mechanistic pathway has been determined based on the kinetic behaviour and the product assignment.
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Affiliation(s)
| | - M. Gopalakrishnan
- Department of Chemistry, Annamalai University, Annamalainagar – 608 002, India
| | - S. Nagarajan
- Department of Chemistry, Annamalai University, Annamalainagar – 608 002, India
| | - N. Sarathi
- Department of Chemistry, Annamalai University, Annamalainagar – 608 002, India
| | - P. Sumathi
- Department of Chemistry, Annamalai University, Annamalainagar – 608 002, India
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Affiliation(s)
- S Suman
- Department of Medicine for the Elderly, Norfolk & Norwich University Hospital, Norwich NR4 7UY, UK.
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Vijila Manonmoni J, Bhagavannarayana G, Ramasamy G, Meenakshisundaram S, Amutha M. Growth, structure and spectral studies of a novel mixed crystal potassium zinc manganese sulphate. Spectrochim Acta A Mol Biomol Spectrosc 2014; 117:9-12. [PMID: 23981410 DOI: 10.1016/j.saa.2013.07.089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 07/18/2013] [Accepted: 07/21/2013] [Indexed: 06/02/2023]
Abstract
Mixed crystals of K2Zn0.84 Mn0.16(SO4)2·6H2O were grown from an equimolar aqueous solution of Tutton's salt, K2 Zn(SO4)2·6H2O and MnSO4 by slow evaporation solution growth technique. The crystal composition as determined by single crystal XRD analysis reveals the co-existence of zinc and manganese in the mixed crystal. The surface morphological changes are observed by scanning electron microscopy. Small variations in cell parameter values, slight shifts in characteristic vibrational patterns in FT-IR and reduction in intensities observed in XRD confirm the crystal stress as a result of formation of mixed crystal. High resolution XRD diffraction estimates the crystalline perfection of the mixed crystal with predominantly vacancy type of defects. It belongs to P21/c space group with cell parameter values, a=6.1530 Å, b=12.2230 Å, c=9.0430 Å, α=β=ν=90°, V=657.56 Å(3), Z=4. High transmittance in the visible region is observed.
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Affiliation(s)
- J Vijila Manonmoni
- Department of Chemistry, Annamalai University, Annamalai Nagar 608002, India
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Ramasamy G, Bhagavannarayana G, Meenakshisundaram S. The concentration effects of s-, p-, d- and f-block element doping on the growth, crystalline perfection and properties of KDP crystals. CrystEngComm 2012. [DOI: 10.1039/c2ce06741b] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kasthuri L, Bhagavannarayana G, Parthiban S, Ramasamy G, Muthu K, Meenakshisundaram S. Rare earth cerium doping effects in nonlinear optical materials: potassiumhydrogen phthalate (KHP) and tris(thiourea)zinc(II) sulfate (ZTS). CrystEngComm 2010. [DOI: 10.1039/b907513e] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bhagavannarayana G, Parthiban S, Chandrasekaran C, Meenakshisundaram S. Effect of alkaline earth and transition metals doping on the properties and crystalline perfection of potassium hydrogen phthalate (KHP) crystals. CrystEngComm 2009. [DOI: 10.1039/b904220b] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Subramanian K, Shankar RB, Meenakshisundaram S, Lakshmi BS, Williams PH, Balakrishnan A. LamB-mediated adherence of enteropathogenic Escherichia coli to HEp-2 cells. J Appl Microbiol 2008; 105:715-22. [PMID: 18397259 DOI: 10.1111/j.1365-2672.2008.03800.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To establish the role of maltoporin (LamB) in adherence of enteropathogenic Escherichia coli (EPEC) to epithelial cells in vitro. METHODS AND RESULTS Three strains, wild type (WT) EPEC, a maltoporin (LamB) mutant DeltalamB, and DH5alpha were used to study adherence to cultured HEp-2 cells. Mutant DeltalamB was found to be deficient in adherence compared to WT EPEC. Adherence of DeltalamB was restored to wild type levels when complemented with the cloned lamB gene. The non-adherent strain DH5alpha also adhered to HEp-2 cells when it harboured the cloned lamB gene. The LamB protein was isolated from WT EPEC by electroelution and antibodies were raised in rabbits. The specificity of the antibodies was analysed by Western blotting. Anti-LamB antiserum reduced adherence of WT EPEC to HEp-2 cells. The LamB protein was coated on latex beads and the beads adhered to HEp-2 cells. Anti-LamB antiserum prevented bead adherence to HEp-2 cells. Multiple sequence alignment showed that the L9 loop of EPEC LamB had four amino acids different from the L9 loop of LamB from several other related pathogens. CONCLUSIONS LamB serves as an alternative or additional adherence factor for EPEC. SIGNIFICANCE AND IMPACT OF THE STUDY Adherence is an important component of the pathogenesis of noninvasive pathogens like EPEC. A putative adhesin such as LamB, which has already been found to be co-expressed with virulence factor EspB may be a potential vaccine candidate for control of EPEC and related pathogens.
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Affiliation(s)
- K Subramanian
- Centre for Biotechnology, Anna University, Chennai, India
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Srinivasa Babu K, Antony A, Muthukumaran T, Meenakshisundaram S. Construction of intein-mediated hGMCSF expression vector and its purification in Pichia pastoris. Protein Expr Purif 2008; 57:201-5. [PMID: 18309571 DOI: 10.1016/j.pep.2007.10.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As a novel attempt for the intracellular recombinant protein over expression and easy purification from Pichia pastoris, the therapeutic cytokine human granulocyte macrophage colony stimulating factor (hGMCSF) gene was fused to an intein-chitin-binding domain (gene from pTYB11 vector) fusion tag by overlap extension PCR and inserted into pPICZB vector, allowing for the purification of a native recombinant protein without the need for enzymatic cleavage. The fusion protein under the AOX1 promoter was integrated into the P. pastoris genome (SMD 1168) and the recombinant Pichia clones were screened for multicopy integrants. Expression of hGMCSF was done using glycerol and methanol based synthetic medium by three stage cultivation in a bioreactor. Purification of the expressed hGMCSF fusion protein was done after cell disruption and binding of the solubilized fusion protein to chitin affinity column, followed by DTT induced on column cleavage of hGMCSF from the intein tag. In this study, final biomass of 89 g dry cell weight/l and purified hGMCSF of 120 mg/l having a specific activity of 0.657 x 10(7) IU/mg was obtained. This strategy has an edge over the other--His or--GST based fusion protein purification where non-specific protein binding, expensive enzymatic cleavage and further purification of the enzyme is required. It distinguishes itself from all other purification systems by its ability to purify, in a single chromatographic step.
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Affiliation(s)
- K Srinivasa Babu
- Centre for Biotechnology, Anna University, Chennai 600025, India
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Janardhan S, Pandiaraja P, Thirugnanam S, Balamurali MN, Fernando K, Mody HC, Desai PK, Meenakshisundaram S, Kaliraj P. Production, purification and diagnostic application of filarial recombinant protein WbSXP-1 expressed in salt inducible Escherichia coli. J Ind Microbiol Biotechnol 2007; 34:675-83. [PMID: 17674066 DOI: 10.1007/s10295-007-0243-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Accepted: 07/09/2007] [Indexed: 10/23/2022]
Abstract
Wuchereria bancrofti protein WbSXP-1 was identified and established as a potential candidate for the diagnosis of lymphatic filariasis. For the economic production of rWbSXP-1, osmotically (salt) inducible Escherichia coli GJ1158 was preferred. Cultivation and expression was optimized in 3 L airlift bioreactor (ALB) and was successfully extended to 30 L ALB. Purification of rWbSXP-1 his-tag protein was optimized in technical scale using FPLC and the maximal recovery of rWbSXP-1 with significant level of purity was achieved using the combination of IMAC and gel filtration. Quality criteria for immuno-reactivity of purified rWbSXP-1 were established for diagnostic applications. Enhancement of sensitivity in rapid diagnostic format was optimized to effectively detect weak to strong antibody reactivity in individuals exposed to lymphatic filariasis. Performance of the rapid format during field evaluation was successful. The accelerated stability assessment of the rapid format satisfied the requirements of WHO-cGMP norms. This investigation presents a successful technical scale production and purification of rWbSXP-1 considering the future industrial application and an enhanced rapid flow through antibody assay for the diagnosis of human lymphatic filariasis.
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Affiliation(s)
- S Janardhan
- Centre for Biotechnology, Anna University, Chennai, India
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Bhagavannarayana G, Parthiban S, Meenakshisundaram S. Enhancement of crystalline perfection by organic dopants in ZTS, ADP and KHP crystals as investigated by high-resolution XRD and SEM. J Appl Crystallogr 2006. [DOI: 10.1107/s0021889806033139] [Citation(s) in RCA: 166] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
To reveal the influence of complexing agents on crystalline perfection, tristhiourea zinc(II) sulfate (ZTS), ammonium dihydrogen phosphate (ADP) and potassium hydrogen phthalate (KHP) crystals grown by slow-evaporation solution growth technique using low concentrations (5 × 10−3M) of dopants like ethylenediamminetetraacetic acid (EDTA) and 1,10-phenanthroline (phen) were characterized by high-resolution X-ray diffractometry (XRD) and scanning electron microscopy (SEM). High-resolution diffraction curves (DCs) recorded for ZTS and ADP crystals doped with EDTA show that the specimen contains an epilayer, as observed by the additional peak in the DC, whereas undoped specimens do not have such additional peaks. On etching the surface layer, the additional peak due to the epilayer disappears and a very sharp DC is obtained, with full width at half-maximum (FWHM) of less than 10 arcsec, as expected from the plane wave dynamical theory of X-ray diffraction for an ideally perfect crystal. SEM micrographs also confirm the existence of an epilayer in doped specimens. The ZTS specimen has a layer with a rough surface morphology, having randomly oriented needles, whereas the ADP specimen contains a layer with dendric structure. In contrast to ADP and ZTS crystals, the DC of phen-doped KHP shows no additional peak, but it is quite broad (FWHM = 28 arcsec) with a high value of integrated intensity, ρ (area under the DC). The broadness of the DC and the high value of ρ indicate the formation of a mosaic layer on the surface of the crystal. However, similar to ADP and ZTS, the DC recorded after etching the surface layer of the KHP specimen shows a very sharp peak with an FWHM of 8 arcsec. An SEM photograph of phen-doped KHP shows deep cracks on the surface, confirming the mosaicity. After removing the surface layer, the SEM pictures reveal a smooth surface. A similar trend is observed with other complexing agents, like oxalic acid, bipy and picolinic acid. However, only typical examples are described in the present article where the effects were observed prominently. The investigations on ZTS, ADP and KHP crystals, employing high-resolution XRD and SEM studies, revealed that some organic dopants added to the solution during the growth lead to the formation of a surface layer, due to complexation of these dopants with the trace metal ion impurities present in the solution, which prevents the entry of impurities, including the solvent, into the crystal, thereby assisting crystal growth with high crystalline perfection. The influence of organic dopants on the second harmonic generation efficiency is also investigated.
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Affiliation(s)
- S Suman
- Department of Medicine for the Elderly, Norfolk & Norwich University Hospital, Norwich NR4 7UY, UK.
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Meenakshisundaram S, Selvaraju M, Gowda NMM, Rangappa KS. Effect of substituents on the rate of oxidation of anilines with peroxomonosulfate monoanion (HOOSO−3) in aqueous acetonitrile: A mechanistic study. INT J CHEM KINET 2005. [DOI: 10.1002/kin.20119] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Meenakshisundaram S, Markkandan R. 1,10-Phenanthroline catalysis of the chromium(VI) oxidation of alcohols: a kinetic and mechanistic study. TRANSIT METAL CHEM 2004. [DOI: 10.1023/b:tmch.0000019410.94049.6b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Meenakshisundaram S, Markkandan R. Kinetics of edta-catalysed oxidation of some cycloalkanones by pyridinium chlorochromate. j chem res (s) 2003. [DOI: 10.3184/030823403322862879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Meenakshisundaram S, Selvaraju M. Kinetics and mechanism of the reaction of ?-phenoxypropanoic acids with sodium salt of N-Chlorobenzene-sulphonamide: EDTA catalysis. INT J CHEM KINET 2002. [DOI: 10.1002/kin.10016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Meenakshisundaram S, Sockalingam R. Enhanced Reactivity in the Quinolinium Fluorochromate Cooxidation of Some Cycloalkanones and Oxalic Acid. BCSJ 2001. [DOI: 10.1246/bcsj.74.1043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Meenakshisundaram S, Sockalingam R. Nonlinear Hammett Relationships in the Reaction of Peroxomonosulfate Anion (HOOSO3-) with meta- and para-Substituted Anilines in Alkaline Medium. ACTA ACUST UNITED AC 2001. [DOI: 10.1135/cccc20010897] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The HOOSO3- oxidation of eleven meta- and para-substituted anilines to the corresponding nitrosobenzenes at pH ≈ 11 was characterized by the rate equation v = kK[OX][An]/(1 + K[An]). Formation constant of the reactive intermediate and its rate of decomposition were evaluated separately for ascertaining the structure-reactivity relationships. Under the experimental conditions the dianion, -O-O-SO3- is probably the effective electrophile. Kinetic data can be rationalized by a bimolecular process which involves the attack of nucleophilic nitrogen atom on the peroxidic oxygen. The highlight of the study is the opposite curvatures observed in the nonlinear Hammett plots of first-order rate constant k and the "equilibrium" constant K, being concave downward and upward, respectively.
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Meenakshisundaram S, Amutha M. Studies on the Oxidation of some Sulfides with Pyridinium Dichromate in Acetonitrile medium. Journal of Chemical Research 1999. [DOI: 10.1177/174751989902300107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The kinetic behaviours of oxidation of dialkyl, alkyl aryl and diphenyl sulfides are quite different with pyridinium dichromate in acetonitrile medium; studies indicate the involvement of a sulfur cation free radical intermediate in diphenyl sulfide oxidation; electron releasing and withdrawing groups retard the reactivity of aryl methyl sulfides; the observed non-linear concave downwards type Hammett plot is well explained by assuming shifts in the rate-limiting step within the same overall reaction pathway.
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Affiliation(s)
| | - M. Amutha
- Department of Chemistry, Annamalai University, Annamalai Nagar - 608 002, India
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Meenakshisundaram S, Amutha M. Studies on the Oxidation of some Sulfides with Pyridinium Dichromate in Acetonitrile medium. J Chem Res 1999. [DOI: 10.1039/a804504f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Rothen SA, Saner M, Meenakshisundaram S, Sonnleitner B, Fiechter A. Glucose uptake kinetics of Saccharomyces cerevisiae monitored with a newly developed FIA. J Biotechnol 1996; 50:1-12. [PMID: 8987846 DOI: 10.1016/0168-1656(96)01500-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The glucose content of the culture liquid during shift experiments and synchronized cultures of Saccharomyces cerevisiae H1022 (ATCC 32167) was monitored using a greatly improved and highly precise FIA. During shift-up experiments on the dilution rate, an overshoot of the glucose-concentration was observed. The amplitude of the overshoot showed a dependency on the duration of undisturbed cultivation before application of the shift. Mutarotational non-equilibrium was excluded as the cause of the observed overshoot. For the first time glucose measurements of oscillating cultures of Saccharomyces cerevisiae are demonstrated with high accuracy and reproducibility. The data strongly support the proposals by Münch et al. (1992a, b) that faint oscillations in glucose concentration are responsible for the persistence of the synchronization. Analytical subsystems prove to be a powerful tool for investigation of the dynamics of metabolic pathways of microbial organisms. Accurate glucose measurements at low concentrations point out the limits and allow refinements of commonly used models.
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Affiliation(s)
- S A Rothen
- Institute of Biotechnology, Swiss Federal Institute of Technology, Zurich, Switzerland
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Ahamed NM, Meenakshisundaram S, Shanmugasundaram ER. Lipids & lipase activity in strains of Fusarium vasinfectum. Indian J Exp Biol 1973; 11:37-9. [PMID: 4779293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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