Pedro Araujo

Seniorforsker

Telefon: +4795285039
Avdeling: Fiskeernæring,Behov og velferd

My research interests include analytical chemistry, checometrics and statistics. My current research involves the development of analytical methodologies for the analysis of lipids with main focus on eicosanoids, fatty acids, triacylglycerol and cholesterol. Another important aspects of my research are the development of multivariate platforms for assesing the stability of fatty acid profiles from different types of biological specimens and also the discrimination of nutritional oils and adulteration based on the positional distribution of fatty acids on the backbone of triacylglycerol structures.



Arbeidsområde
Utvalgte publikasjoner
Prosjekter
Vitenskaplige publikasjoner



  • Liquid Chromatography Mass Spectrometry (LCMS)

  • Gas Chromatography

  • Chemometrics

  • Statistics



2010-2014

Araujo P., Lucena E., Yang Y, Ceemala B, Mengesha Z, Holen E. (2014) The impact of exogenous ω-6 and ω-3 polyunsaturated fatty acids on the induced production of pro- and anti-inflammatory prostaglandins and leukotrienes in Atlantic salmon head kidney cells using a full factorial design and LC-MS/MS. Journal of Chromtaography B (in press).

Araujo P., Mengesha Z., Lucena E, Grung B. (2014) Development and validation of an extraction method for the determination of pro-inflammatory eicosanoids in human plasma using liquid chromatography tandem mass spectrometry. Journal of Chromatography A (in press)

Araujo P., Zhu H., Breivik J.F., Hjelle J.I., Zeng Y. (2014) Determination and structural elucidation of triacylglycerols in krill oil by chromatographic techniques. Lipids 49:163-172 .

Holen E., Espe M., Andersen S.M., Taylor R., Aksnes A., Mengesha Z., Araujo P. (2014) A co culture approach show that polyamine turnover is affected during inflammation in Atlantic salmon immune and liver cells and that arginine and LPS exerts opposite effects on p38MAPK signaling. Fish & Shellfish Immunology 37:286-298.

Tsikas D., Böhmer A., Mitscheke A., Araujo P. (2013) Accurate measurement of nitrate, nitrite, and S-nitrosothiols in biological samples by mass spectrometry. Free Radical Biology and Medicine 65:301-304.

Furne M.C., Holen E., Araujo P., Lie K.K., Moren M. (2013) Cytokine gene expression and prostaglandin production in head kidney leukocytes isolated from Atlantic cod ( Gadus morhua ) added different levels of arachidonic acid and eicosapentaenoic acid. Fish and Shellfish Immunology 34:770-777.

Du Z-Y., Ma T., Liaset B., Araujo P., Lock E-J., Demizieux L., Degrace P., Frøyland L., Kristiansen K., Madsen L. (2013) Dietary eicosapentaenoic acid supplementation accentuates hepatic triglyceride accumulation in mice with impaired fatty acid oxidation capacity. Biochimica et Biophysica Acta 1831:291-299.

Araujo P., Janagap S., Holen E. (2012) C Application of Doehlert uniform shell designs for selecting optimal amounts of internal standards in the analysis of prostaglandins and leukotrienes by liquid chromatography–tandem mass spectrometry. Journal of Chromatography A 1260:102-110.

Araujo P., Janagap S. (2012) Doehlert uniform shell designs and chromatography. Journal of Chromatography B 910:14-21.

Araujo P., Grung B. (2012) Preface: Chemometrics in chromatography. Journal of Chromatography B 910:1.

Janagap S., Azeredo R., Nguyen T-T., Hamre K., Araujo P (2012) Development of an extraction method for the determination of prostaglandins in biological tissue samples using liquid chromatography-tandem mass spectrometry: application to gonads of Atlantic cod (Gadus morhua). Analytica Chimica Acta 749:51-55.

Holen E., Lie K.K., Araujo P., Olsvik P.A. (2012) Pathogen recognition and mechanisms in Atlantic cod (Gadus morhua) head kidney cells.  Bacteria (LPS) and virus (poly I:C) signals through different pathways and affect distinct genes. Fish and Shellfish Immunology 33:267-276.

Gregersen K., Valeur J., Lillestøl K., Frøyland L., Araujo P., Lied G.A., Berstad B. (2011) Subjective food hypersensitivity: assessment of enterochromaffin cell markers in blood and gut lavage fluid. International Journal of General Medicine 4:555-560.

Zeng Y., Araujo P., Grung B., Zhang L. (2011) Evaluation of different fingerprinting strategies for differentiating marine oils by liquid chromatography ion-trap- mass spectrometry and chemometrics. Analyst 136, 1507-1514.

Araujo P., Zeng Y., Du Z., Nguyen T., Frøyland L., Grung B. (2010) Discrimination of n-3 rich oils by gas chromatography. Lipids 45:1147-1158.

Martens L.G., Lock E.J., Fjelldal P.G., Wargelius A., Araujo P., Torstensen B., Witten E., Hansen T., Waagbø R., Ørnsrud R. (2010) Dietary fatty acids and inflammation in the vertebral column of Atlantic salmon (Salmo salar) smolts: a possible link to spinal deformities. Journal of Fish Diseases 33:957-972.

Zeng Y., Araujo P., Du Z., Nguyen T-T., Frøyland L., Grung B. (2010) Elucidation of triacylglycerols in cod liver oil by liquid chromatography electrospray tandem ion-trap mass spectrometry. Talanta 82:1261-1270.

Hallenborg P., Jørgensen C., Petersen R.K., Feddersen S., Araujo P., Markt P., Langer T., Furstenberger G., Krieg P., Koppen A., Kalkhoven E., Madsen L., Kristiansen K. (2010) Epidermis-Type lipoxygenase 3 regulates adipocyte differentiation and peroxisome proliferator-activated receptor activity. Molecular and Cellular Biology 30:4077-4091.

Madsen L., Pedersen L.M., Lillefosse H.H., Fjære E., Bronstad I., Hao Q., Petersen R.K., Hallenborg P., Ma T., De Matteis R., Araujo P., Mercader J., Bonet M.L., Hansen J.B., Cannon B., Nedergaard J., Wang J., Cinti S., Voshol P., Døskeland S.O., Kristiansen K. (2010) UCP1 induction during recruitment of brown adipocytes in white adipose tissue is dependent on cyclooxigenase activity. PloS ONE 5:1-13.

Du Z., Araujo P., Stubhaug I., Frøyland L. (2010) Unbound DHA causes a high blank value in β-oxidation assay: a concern for in vitro studies. European Journal of Lipid Science and Technology 112:333-342.

2000-2009

Araujo P. (2009) Key aspects of analytical method validation and linearity evaluation. Journal of Chromatography B 877:2224-2234.

Bjørkkjær T., Araujo P., Madland T.M., Berstad A., Frøyland L. (2009) A randomized double blind comparison of short-term duodenally administrated whale and seal blubber oils in patients with inflammatory bowel disease and joint pain . Prostaglandins, Leukotrienes and Essential Fatty Acids 81:425-432

Araujo P., Nguyen T.T., Frøyland L., Wang J., Kang J-X. (2008) Evaluation of a rapid method for the quantitative analysis of fatty acids in various matrices. Journal of chromatography A 1212:106-113.

Araujo P. (2008) Variability, confidence and statistical power in aquaculture experiments. Israeli Journal of Aquaculture 60:134-153.

Araujo P., Du Z-Y., Nguyen T-T., Holen E. (2008) Direct injection of redissolved cell culture media into a single-column liquid chromatography coupled to mass spectrometry for the measurement of PGE 2 . Open Analytical Chemistry Journal 2:62-68.

Gregersen K. Frøyland L. Berstad A., Araujo P. (2008) Direct determination of serotonin in gut lavage fluid by liquid chromatographic ion trap tandem mass spectrometry. Talanta 75: 466-472.

Araujo P., Bjørkkjær T., Berstad A., Frøyland L. (2007) Improved quantification of prostaglandins in biological samples by optimizing simultaneously the relationship eicosanoid/internal-standard and using liquid chromatography tandem mass spectrometry. Prostaglandins Leukotrienes And Essential Fatty Acids 77: 9-13.

Araujo P., Frøyland L. (2007) Statistical power and analytical quantification. Journal of Chromatography A 112:99-105.

Araujo P., Couillard F., Leirnes E., Ask K., Bøkevoll A., Frøyland L. (2006)* Experimental design considerations in quantification experiments by using the internal standard technique: Cholesterol determination by gas chromatography as a case study. Journal of Chromatography A 1121:99-105. *NIFES current nationally accredited method for quantitative analysis of cholesterol is based on this article.

Araujo P., Frøyland L. (2006)** Optimisation of an extraction method for the determination of prostaglandin E 2 in plasma using experimental design and liquid chromatography tandem mass spectrometry. Journal of Chromatography B 830:212-217. **Also available in Fish Oil  Research Today Volume 3,  Issue 1 (January 2006) ( http://fishoil.researchtoday.net/ ).

Araujo P., Frøyland L. (2006) Hierarchical classification designs for the estimation of different sources of variability in proficiency testing experiments Analytica Chimica Acta 555:348-353.

Araujo P., Nguyen T-T., Frøyland L. (2005) Chemometric Approaches in Calibration Experiments of Trilinolenoylglycerol by Liquid Chromatography Ion-Trap Mass Spectrometry. Journal of the American Society for Mass Spectrometry 16:388-396.

Araujo P., Frøyland L. (2005) Statistical Approach to the Rational Selection of Experimental Subjects. Accreditation and Quality Assurance 10:185-189.

Araujo P., Konstantopoulou M., Georgakopoulos G., Mazomenos B. (2002) Isolation and identification of toxic metabolites to fruit fly adults from Mucor hiemalis SMU-21. Environmental Science and Pollution Research (ESPR) 9:246.

Araujo P. (2000) New high performance liquid chromatography multifactor methodology for systematic and simultaneous optimisation of the gradient solvent system and the instrumental-experimental variables. Trends in Analytical Chemistry 19: 524-529.

1990-1999

Benzo Z., Salas J., Araujo P.W., Camardiel A., Carrión N. (1998) Estimation of experimental parameters for the determination of ruthenium by flame atomic absorption spectroscopy. Chemometrics and Intelligent Laboratory Systems 40:109-117.

Araujo P.W., Brereton R. (1997) Visualisation of confidence in two-factor designs where model, replication and star points are varied. Analyst 122:621-630.

Araujo P.W., Cirovic D.A., Brereton R.G. (1996) Multivariate calibration of chlorophyll a using partial least squares and electronic absorption spectroscopy. Analyst 121:581-584.

Araujo P.W., Brereton R.G. (1996) Review: Experimental design. III. Quantification. Trends in Analytical Chemistry 15:156-163.

Araujo P.W., Brereton R.G. (1996) Review: Experimental design. II. Optimisation. Trends in Analytical Chemistry 15:63-70.

Araujo P.W., Brereton R.G. (1996) Review: Experimental design. I. Screening. Trends in Analytical Chemistry 15:26-31.

Araujo P.W., Brereton R.G. (1995) Rational design of linear calibration experiments for the quantitative estimation of chlorophyll a using high-performance liquid chromatography, atomic absorption spectrometry and electronic absorption spectrometry. Analyst 120:2497-2504.

Araujo P.W., Kavianpour K., Brereton R.G. (1995) Development of a novel methodology in the determination of magnesium from chlorophyll a by atomic absorption spectrometry using chemometric experimental design. Analyst 120:295-298.

Araujo P.W., Brereton R.G. (1995) Stability studies of chlorophyll a using different storage systems. Analytical Proceedings Including Analytical Communications 32:415-417.

Araujo P.W., Marcano E., Gómez C.V., Benzo Z. (1995) Application of a fractional factorial design for the determination of cadmium by ETA-AAS in different atomisation systems. Fresenius Journal Analytical Chemistry 351:204-208.

Araujo P.W., Marcano E., Gómez C.V., Benzo Z. (1994) Multivariate optimisation of the cadmium determination conditions in cocoa seeds by electrothermal atomisation spectrometry with platform. Anales de Química 90:343-347.

Benzo Z., Araujo P.W., Sierralta A., Ruette F. (1993) Experimental and theoretical studies of the factors that influence the determination of molybdenum by electrothermal atomic absorption spectroscopy. Analytical Chemistry 65:1107-1113.

Sierralta A., Benzo Z., Araujo P.W., Ruette F. (1992) Theoretical modelling of molybdenum interaction with a graphite furnace surface. Journal of Molecular Structure (Theochem) 254:387-393.

Araujo P.W., Gómez M.J., Benzo Z.A., Castillo C. (1992) Use of experimental designs for the determination of optimum electrothermal atomic absorption conditions for molybdenum. Chemometrics and Intelligent Laboratory Systems 16:203-211.

Burguera J., Burguera M., Araujo P.W., López S., Benzo Z., Schorin H., Marcano E. (1990) Determination of indium in semiconductors: comparison of methods. Acta Científica Venezolana 41:93-96.

Book Chapter

Kavianpour K., Araujo P.W. and Brereton R.G (1995) Quantitative determination of chlorophyll A. In: Frontiers in Analytical Spectroscopy , edited by D.L. Andrews, A.M.C. Davies. Royal Society of Chemistry Cambridge, pp VIII + 248 ISBN: 0854047301 (pp 136-143).

Book Reviews

(2000) Nonlinear Computer Modeling of Chemical and Biochemical Data by James F. Rusling and Thomas F. Kumosinski, Academic Press, pp XV + 268 ISBN: 0-12-604490-2. Comments in Analytica Chimica Acta 419: 117-118.

(1997) Chemometrics: Experimental Design ’ by Ed Morgan., John Wiley & Sons, pp XVIII + 275 ISBN: 0-471-95832-8. Comments in Chemometrics and Intelligent Laboratory Systems 36: 249.

  • 2015


    Elisabeth Holen, Juyun He, Marit Espe, Liqiou Chen, Pedro Araujo

    Combining eicosapentaenoic acid, decosahexaenoic acid and arachidonic acid, using a fully crossed design, affect gene expression and eicosanoid secretion in salmon head kidney cells invitro

    Fish and Shellfish Immunology; Volum 45.(2) S. 695-703
    • År: 2015
  • 2014


    Pedro Araujo, Han Zhu, Joar Fjørtoft Breivik, Jan Idar Hjelle, Yingxu Zeng

    Determination and structural elucidation of triacylglycerols in krill oil by chromatographic techniques

    Lipids; Volum 49.(2) S. 163-172
    • År: 2014

    Pedro Araujo, Zebasil Tassew Mengesha, Eva Lucena, Bjørn Grung

    Development and validation of an extraction method for the determination of pro-inflammatory eicosanoids in human plasma using liquid chromatography-tandem mass spectrometry

    Journal of Chromatography A; Volum 1353. S. 57-64
    • År: 2014

    Pedro Araujo, Eva Lucena, Yang Yang, Bupesh Ceemala, Zebasil Tassew Mengesha, Elisabeth Holen

    The impact of exogenous ω-6 and ω-3 polyunsaturated fatty acids on the induced production of pro- and anti-inflammatory prostaglandins and leukotrienes in Atlantic salmon head kidney cells using a full factorial design and LC-MS/MS

    Journal of chromatography. B; Volum 964. S. 164-171
    • År: 2014

    Elisabeth Holen, Marit Espe, Synne Marte Andersen, Richard Taylor, Anders Aksnes, Zebasil Tassew Mengesha, Pedro Araujo

    A co culture approach show that polyamine turnover is affected during inflammation in Atlantic salmon immune and liver cells and that arginine and LPS exerts opposite effects on p38MAPK signaling

    Fish and Shellfish Immunology; Volum 37.(2) S. 286-298
    • År: 2014
  • 2013


    Miriam Furné Castillo, Elisabeth Holen, Pedro Araujo, Kai Kristoffer Lie, Mari Moren

    Cytokine gene expression and prostaglandin production in head kidney leukocytes isolated from Atlantic cod (Gadus morhua) added different levels of arachidonic acid and eicosapentaenoic acid

    Fish and Shellfish Immunology; Volum 34.(3) S. 770-777
    • År: 2013

    Zhen-yu Du, Tao Ma, Bjørn Liaset, Alison H. Keenan, Pedro Araujo, Erik-Jan Lock, Laurent Demizieux, Pascal Degrace, Livar Frøyland, Karsten Kristiansen, Lise Madsen

    Dietary eicosapentaenoic acid supplementation accentuates hepatic triglyceride accumulation in mice with impaired fatty acid oxidation capacity

    Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids; Volum 1831.(2) S. 291-299
    • År: 2013
  • 2012


    Elisabeth Holen, Kai Kristoffer Lie, Hernandez Pedro W. Araujo, Pål Asgeir Olsvik

    Pathogen recognition and mechanisms in Atlantic cod (Gadus morhua) head kidney cells Bacteria (LPS) and virus (poly I:C) signals through different pathways and affect distinct genes

    Fish and Shellfish Immunology; Volum 33.(2) S. 267-276
    • År: 2012

    Hernandez Pedro W. Araujo, Steve Janagap, Elisabeth Holen

    Application of Doehlert uniform shell designs for selecting optimal amounts of internal standards in the analysis of prostaglandins and leukotrienes by liquid chromatography-tandem mass spectrometry

    Journal of Chromatography A; Volum 1260. S. 102-110
    • År: 2012

    Steve Janagap, Rita Azeredo, Thu Thao Nguyen, Kristin Hamre, Hernandez Pedro W. Araujo

    Development of an extraction method for the determination of prostaglandins in biological tissue samples using liquid chromatography-tandem mass spectrometry: Application to gonads of Atlantic cod (Gadus morhua)

    Analytica Chimica Acta; Volum 749. S. 51-55
    • År: 2012

    Pedro Araujo, Bjørn Grung

    Chemometrics in chromatography

    Journal of chromatography. B; Volum 910. S. 1
    • År: 2012
  • 2011


    Yingxu Zeng, HERNANDEZ PEDRO W ARAUJO, Bjørn Grung, Liangxiao Zhang

    Evaluation of different fingerprinting strategies for differentiating marine oils by liquid chromatography ion-trap mass spectrometry and chemometrics

    The Analyst; Volum 136.(7) S. 1507-1514
    • År: 2011

    Kine Gregersen, Jørgen Valeur, Kristine Lillestøl, Livar Frøyland, Hernandez Pedro W. Araujo, Gülen Arsland Lied, Arnold Berstad

    Subjective food hypersensitivity: assessment of enterochromaffin cell markers in blood and gut lavage fluid

    International Journal of General Medicine; Volum 4. S. 555-560
    • År: 2011
  • 2010


    Lise Madsen, Lone M Pedersen, Haldis Haukås Lillefosse, Even Fjaere, Ingeborg Brønstad, Qin Hao, Rasmus Kofoed Petersen, Philip Hallenborg, Tao Ma, Rita De Matteis, HERNANDEZ PEDRO W ARAUJO, Josep Mercader, M Louisa Bonet, Jacob B Hansen, Barbara Cannon, Jan Nedergaard, Jun Wang, Saverio Cinti, Peter Voshol, Stein Ove Doskeland, Karsten Kristiansen

    UCP1 Induction during Recruitment of Brown Adipocytes in White Adipose Tissue Is Dependent on Cyclooxygenase Activity

    PLoS ONE; Volum 5.(6)
    • År: 2010

    Yingxu Zeng, HERNANDEZ PEDRO W ARAUJO, ZHEN-YU DU, Thu-Thao Nguyen, Livar Frøyland, Bjørn Grung

    Elucidation of triacylglycerols in cod liver oil by liquid chromatography electrospray tandem ion-trap mass spectrometry

    Talanta: The International Journal of Pure and Applied Analytical Chemistry; Volum 82.(4) S. 1261-1270
    • År: 2010

    HERNANDEZ PEDRO W ARAUJO, Yingxu Zeng, ZHEN-YU DU, Thu-Thao Nguyen, Livar Frøyland, Bjørn Grung

    Discrimination of n-3 rich oils by gas chromatography

    Lipids; Volum 45.(12) S. 1147-1158
    • År: 2010

    ZHEN-YU DU, HERNANDEZ PEDRO W ARAUJO, Ingunn Stubhaug, Livar Frøyland

    Unbound DHA causes a high blank value in beta-oxidation assay: a concern for in vitro studies

    European Journal of Lipid Science and Technology; Volum 112.(3) S. 333-342
    • År: 2010

    Philip Hallenborg, Claus Jørgensen, Rasmus K. Petersen, Søren Feddersen, HERNANDEZ PEDRO W ARAUJO, Patrick Markt, Thierry Langer, Gerhard Furstenberger, Peter Krieg, Arjen Koppen, Eric Kalkhoven, Lise Madsen, K Kristiansen

    Epidermis-Type Lipoxygenase 3 Regulates Adipocyte Differentiation and Peroxisome Proliferator-Activated Receptor Activity

    Molecular and Cellular Biology; Volum 30.(16) S. 4077-4091
    • År: 2010

    Laura Gil Martens, ERIK-JAN LOCK, Per Gunnar Fjelldal, Anna Wargelius, HERNANDEZ PEDRO W ARAUJO, BENTE ELISABETH TORSTENSEN, P. Eckhard Witten, Tom Hansen, Rune Waagbø, ROBIN ØRNSRUD

    Dietary fatty acids and inflammation in the vertebral column of Atlantic salmon, Salmo salar L., smolts: a possible link to spinal deformities

    Journal of Fish Diseases; Volum 33.(12) S. 957-972
    • År: 2010
  • 2009


    Tormod Bjørkkjær, HERNANDEZ PEDRO W ARAUJO, Tor Magne Madland, Arnold Berstad, Livar Frøyland

    A randomized double blind comparison of short-term duodenally administrated whale and seal blubber oils in patients with inflammatory bowel disease and joint pain

    Prostaglandins, Leukotrienes and Essential Fatty Acids; Volum 81.(5-6) S. 425-432
    • År: 2009