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Garreta Gambús I Albert - One of the best experts on this subject based on the ideXlab platform.

  • Cristal·lització de la lipoxigenasa de "Pseudomonas aeruginosa" 42A2 i estudi filogenètic de les subfamílies de les lipoxigenases (Tesi)
    'Edicions de la Universitat de Barcelona', 2010
    Co-Authors: Garreta Gambús I Albert
    Abstract:

    [cat] Les lipoxigenases són conegudes com les responsables de la catàlisi d'oxigenació molecular d’àcids grassos poli-insaturats que forma un producte hydroperoxid (tòxic) que es pot convertir en una gran varietat de metabòlits secundaris. Durant anys, la presència de lipoxgenases ha estat descrita únicament en organismes eucariotes, mamífers, plantes, petits invertebrats marins i fongs. La funció biològica de les lipoxigenases eucariotes ha estat àmpliament estudiada. Estan involucrades en la síntesi de molècules de senyalització com els leucotriens, en mamífers, o en la de l’àcid jasmònic, en plantes. L’any 1964, Shimahara, publicava la presència d’una lipoxigenasa en un bacteri gram-negatiu aïllat de les escombraries. Encara avui són poques les informacions referents a lipoxigenases bacterianes que s'han publicat, alguns exemples són les de Thermoactinomyces vulgaris, Pseudomonas i Nostoc punctiforme. Els anàlisis que s’han realitzat utilitzant el programa BLAST, indiquen que hi ha gens “LOX-like” en Shewanella, Burkolderia, Nitrosomonas i Myxococcus, però la funció biològica de lipoxigenases procariotes encara no s'ha aclarit. No obstant, les lipoxigenases publicades en la base de dades “gene data-bank” són d’organismes ambientals de medi marí i de sòls, això suggereix que les lipoxigenases poden tenir un paper important en la biodegradació. En aquest estudi es reporta la primera estructura molecular d'una lipoxigenasa procariota i un estudi preliminar de la filogènia d’aquest grup de proteïnes.[eng] The lipoxygenases are known as responsible for the reaction of oxygenation of Poly-Unsaturated Fatty Acid producing hydroperoxid Acids (toxic) that can be converted into a different secondary metabolites. For years, the presence of lipoxygenases has been described only in eukaryotes, mammals, plants, fungi and small invertebrates. The biological function of eukaryotic lipoxygenases has been widely studied. They are involved in the synthesis of leukotrienes as signaling molecules in mammals, or in the jasmonic Acid in plants. In 1964, Shimahara, published the existence of lipoxygenases of gram-negative bacteria isolated from the trash. Even today there are few data concerning bacterial lipoxygenases published. Some examples are those of Thermoactinomyces vulgaris, Pseudomonas and Nostoc punctiforme. The analysis were performed using the BLAST program and the results indicate that there are "LOX-like" genes in Shewanella, Burkolderia, Nitrosomonas and Myxococcus, but the biological function of prokaryotic lipoxygenases is not yet clear. However, lipoxygenases published in the database "gene data-bank" are marine organisms and environmental grounds, suggesting that the lipoxygenases can play an important role in biodegradation. This study reports the first molecular structure of a prokaryotic lipoxygenasa and a preliminary study of the phylogeny of this group of proteins

  • Cristal•lització de la lipoxigenasa de "Pseudomonas aeruginosa" 42A2 i estudi filogenètic de les subfamílies de les lipoxigenases
    'Edicions de la Universitat de Barcelona', 2010
    Co-Authors: Garreta Gambús I Albert
    Abstract:

    Les lipoxigenases són conegudes com les responsables de la catàlisi d'oxigenació molecular d’àcids grassos poli-insaturats que forma un producte hydroperoxid (tòxic) que es pot convertir en una gran varietat de metabòlits secundaris. Durant anys, la presència de lipoxgenases ha estat descrita únicament en organismes eucariotes, mamífers, plantes, petits invertebrats marins i fongs. La funció biològica de les lipoxigenases eucariotes ha estat àmpliament estudiada. Estan involucrades en la síntesi de molècules de senyalització com els leucotriens, en mamífers, o en la de l’àcid jasmònic, en plantes. L’any 1964, Shimahara, publicava la presència d’una lipoxigenasa en un bacteri gram-negatiu aïllat de les escombraries. Encara avui són poques les informacions referents a lipoxigenases bacterianes que s'han publicat, alguns exemples són les de Thermoactinomyces vulgaris, Pseudomonas i Nostoc punctiforme. Els anàlisis que s’han realitzat utilitzant el programa BLAST, indiquen que hi ha gens “LOX-like” en Shewanella, Burkolderia, Nitrosomonas i Myxococcus, però la funció biològica de lipoxigenases procariotes encara no s'ha aclarit. No obstant, les lipoxigenases publicades en la base de dades “gene data-bank” són d’organismes ambientals de medi marí i de sòls, això suggereix que les lipoxigenases poden tenir un paper important en la biodegradació. En aquest estudi es reporta la primera estructura molecular d'una lipoxigenasa procariota i un estudi preliminar de la filogènia d’aquest grup de proteïnes.The lipoxygenases are known as responsible for the reaction of oxygenation of Poly-Unsaturated Fatty Acid producing hydroperoxid Acids (toxic) that can be converted into a different secondary metabolites. For years, the presence of lipoxygenases has been described only in eukaryotes, mammals, plants, fungi and small invertebrates. The biological function of eukaryotic lipoxygenases has been widely studied. They are involved in the synthesis of leukotrienes as signaling molecules in mammals, or in the jasmonic Acid in plants. In 1964, Shimahara, published the existence of lipoxygenases of gram-negative bacteria isolated from the trash. Even today there are few data concerning bacterial lipoxygenases published. Some examples are those of Thermoactinomyces vulgaris, Pseudomonas and Nostoc punctiforme. The analysis were performed using the BLAST program and the results indicate that there are "LOX-like" genes in Shewanella, Burkolderia, Nitrosomonas and Myxococcus, but the biological function of prokaryotic lipoxygenases is not yet clear. However, lipoxygenases published in the database "gene data-bank" are marine organisms and environmental grounds, suggesting that the lipoxygenases can play an important role in biodegradation. This study reports the first molecular structure of a prokaryotic lipoxygenasa and a preliminary study of the phylogeny of this group of proteins

K. Sambaiah - One of the best experts on this subject based on the ideXlab platform.

  • Enrichment of Rice Bran Oil with α-Linolenic Acid by Enzymatic Acidolysis: Optimization of Parameters by Response Surface Methodology
    Food and Bioprocess Technology, 2011
    Co-Authors: Rajni Chopra, N. K. Rastogi, K. Sambaiah
    Abstract:

    Lipase-catalyzed enrichment of rice bran oil with n -3 Fatty Acid in order to obtain a structured lipid containing essential Fatty Acids has been optimized by response surface methodology. In this process, α-linolenic Acid was used as an acyl donor using lipase-catalyzed Acidolysis in hexane in presence of immobilized lipase from Rhizomucor miehei . The effect of incubation time and temperature, enzyme concentration and substrates mole ratio and their complex interaction on percentage incorporation of n -3 Fatty Acid, ratios of saturated Fatty Acid to polyunsaturated Fatty Acids, monounsaturated Fatty Acids to polyunsaturated Fatty Acids and n -6 to n -3 (18:2 to 18:3) Fatty Acids have been studied using a central composite rotatable design of experiments. The results showed that at the optimum conditions such as reaction time 4.5 h and reaction temperature 37. 5°C, substrate ratio ranging from 1.0 to 1.9, enzyme concentration varying from 1.0% to 2.0% are needed to fulfill the conditions such as percentage incorporation of n -3 Fatty Acid ≤18%, ratio of saturated Fatty Acid to poly unsaturated Fatty Acid ≥0.42, ratio of mono unsaturated Fatty Acid to poly unsaturated Fatty Acid ≥0.8, and ratio of n -6 to n -3 ≥1.30.

Norbert Rolland - One of the best experts on this subject based on the ideXlab platform.

  • the chloroplast membrane associated ceqorh putative quinone oxidoreductase reduces long chain stress related oxidized lipids
    Phytochemistry, 2016
    Co-Authors: Gilles Curien, Jean-luc Montillet, Sarah Masymas, David Cobessi, Jeanluc Ferrer, Michel Matringe, Alexander N Grechkin, Cécile Giustini, Norbert Rolland
    Abstract:

    Abstract Under oxidative stress conditions the lipid constituents of cells can undergo oxidation whose frequent consequence is the production of highly reactive α,β-unsaturated carbonyls. These molecules are toxic because they can add to biomolecules (such as proteins and nucleic Acids) and several enzyme activities cooperate to eliminate these reactive electrophile species. CeQORH (chloroplast envelope Quinone Oxidoreductase Homolog, At4g13010) is associated with the inner membrane of the chloroplast envelope and imported into the organelle by an alternative import pathway. In the present study, we show that the recombinant ceQORH exhibits the activity of a NADPH-dependent α,β-unsaturated oxoene reductase reducing the double bond of medium-chain ( C  ⩾ 9) to long-chain (18 carbon atoms) reactive electrophile species deriving from Poly-Unsaturated Fatty Acid peroxides. The best substrates of ceQORH are 13-lipoxygenase-derived γ-ketols. γ-Ketols are spontaneously produced in the chloroplast from the unstable allene oxide formed in the biochemical pathway leading to 12-oxo-phytodienoic Acid, a precursor of the defense hormone jasmonate. In chloroplasts, ceQORH could detoxify 13-lipoxygenase-derived γ-ketols at their production sites in the membranes. This finding opens new routes toward the understanding of γ-ketols role and detoxification.

Hartik H. - One of the best experts on this subject based on the ideXlab platform.

  • Potensi Pemberian Cod Liver Oil (CLO) Pada Pakan Komersial Terhadap Jumlah Total Asam Lemak Omega 3 Dan Omega 6 Di Daging Udang Galah (Macrobrachium Rosenbergii) [Potential of Giving Cod Liver Oil (CLO) Commercial Feed on to the Total Amount of Omega
    Airlangga University, 2017
    Co-Authors: Rahardja B. S., Agustono A., Hartik H.
    Abstract:

    Asam lemak omega 3 dan omega 6 adalah asam lemak tak jenuh yang termasuk kedalam golongan Poly Unsaturated Fatty Acid (PUFA) dan juga termasuk dalam kelompok asam lemak esensial. Asam lemak omega 3 dan omega 6 tidak dapat disintesis sendiri oleh tubuh, sehingga perlu adanya suplai asam lemak omega 3 dan omega 6 di makanan yang dikonsumsi. Fungsi dari asam lemak omega 3 dan omega 6 secara fisiologis yaitu sebagai sumber penting dalam menunjang pertumbuhan dan kelangsungan hidup krustacea. Penelitian ini bertujuan untuk mengetahui potensi pemberian Cod Liver Oil (CLO) pada pakan komersial terhadap jumlah total asam lemak omega 3 dan omega 6 di daging udang galah (Macrobrachium rosenbergii). Metode penelitian yang digunakan adalah percobaan dengan Rancangan Acak Lengkap sebagai rancangan percobaan. Perlakuan yang digunakan adalah kandungan Cod Liver Oil (CLO) yang berbeda, yaitu P0 (0%), P1 (3%), P2(6%), P3 (9%), P4(12%) masing-masing perlakuan diulang sebanyak 4 kali. Parameter utama yang diamati adalah jumlah total asam lemak omega 3 dan omega 6 di daging udang galah. Parameter penunjang yang diamati adalah parameter kualitas air. Analisis data menggunakan analisis of varian (ANOVA) dan untuk mengetahui perlakuan terbaik dilakukan uji jarak berganda Duncan. Hasil penelitian pemberian Cod Liver Oil (CLO) menunjukkan berbeda nyata (P0,05) dengan jumlah total asam lemak omrga 6 di daging udang galah (Macrobrachium rosenbergii). Jumlah total asam lemak omega 3 pada perlakuan P0 (0%) berbeda nyata dengan perlakuan P2 (6%), P3 (9%) dan P4 (12%), tetapi tidak berbeda nyata dengan perlakuan P1. Jumlah total asam lemak omega 6 pada perlakuan P0 (0%) tidak berbeda nyata dengan perlakuan P1 (3%), P2 (6%), P3 (9%) dan P4 (12%)

Gheysen L - One of the best experts on this subject based on the ideXlab platform.

  • Oxidative stability of omega-3 long chain Poly-Unsaturated Fatty Acids in vegetable purees enriched with microalgae
    2019
    Co-Authors: Gheysen L
    Abstract:

    Fruit and vegetables are important carriers of bio-active components whereof the daily intake by the major part of the population is often too low. The largest part of fruit and vegetables is consumed as low fat dispersed food like juices, sauces and soups. Microalgae on theirside have been identified as a source of omega-3 long chain Poly-Unsaturated Fatty Acid. The objective of this Ph.D. is to combine the potential of both products by enriching fruit and vegetable based products with microalgae. The potential of different microalgae will be screened. The microalgae will be suspended as biomass as well as oil in a buffered aqueous solution and will be thermally and HPH treated. The homogenous suspensions will be chemically analyzed with different technics on total lipid content, lipid profile, phenolic, tocopherol and ascorbic Acid content, carotenoid content, … Based on those results a selection of a few microalgae will be made for further experiments. Afterwards the impact of processing and storage will be examined on the lipid stability of the selected microalgae adjusted in real fruit- and vegetable matrices. Also the flavor of the matrices will be examined. Those researches will bring more insight in the stability of lipids of microalgae in fruit and vegetable matrices and in the potential to combine both components to boost the nutritional value.status: publishe