Blar i forfatter "Hansen, Espen"

Viser treff 21-28 av 28

    • A Novel Brominated Alkaloid Securidine A, Isolated from the Marine Bryozoan Securiflustra securifrons 

      Michael, Priyanka; Hanssen, Kine Østnes; Isaksson, Johan; Andersen, Jeanette Hammer; Hansen, Espen (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-23)
      A novel brominated alkaloid, Securidine A, was isolated from the cold water marine bryozoan Securiflustra securifrons. Securidine A was isolated using semi-preparative HPLC, and the structure was elucidated by spectroscopic methods. The isolated Securidine A was tested for cytotoxic, antibacterial, and anti-diabetic activities as well as for its potential for inhibition of biofilm formation. No ...

    • A Novel brominated Alkaloid Securidine A, Isolated from the Marine Bryozoan Securiflustra securifrons 

      Michael, Priyanka; Hansen, Kine Ø.; Isaksson, Johan; Andersen, Jeanette Hammer; Hansen, Espen (Conference object; Konferansebidrag, 2017)
      A novel brominated alkaloid, Securidine A, was isolated from the cold water marine bryozoan Securiflustra securifrons. Securidine A was isolated using semi-preparative HPLC, and the structure was elucidated by spectroscopic methods. The isolated Securidine A was tested for cytotoxic, antibacterial, and anti-diabetic activities as well as for its potential for inhibition of biofilm formation. No ...

    • Ponasterone A and F, Ecdysteroids from the Arctic Bryozoan Alcyonidium gelatinosum 

      Østnes Hanssen, Kine; Isaksson, Johan; Glomsaker, Eirin; Andersen, Jeanette hammer; Hansen, Espen (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-06-19)
      A new ecdysteroid, ponasterone F (1) and the previously reported compound ponasterone A (2) were isolated from specimens of the Arctic marine bryozoan Alcyonidium gelatinosum collected at Hopenbanken, off the coast of Edgeøya, Svalbard. The structure of 1 was elucidated, and the structure of 2 confirmed by spectroscopic methods including 1D and 2D NMR and analysis of HR-MS data. The compounds were ...

    • Qualitative and Quantitative Comparison of Liquid–Liquid Phase Extraction Using Ethyl Acetate and Liquid–Solid Phase Extraction Using Poly-Benzyl-Resin for Natural Products 

      Schneider, Yannik Karl-Heinz; Andersen, Jeanette Hammer; Hansen, Espen; Jørgensen, Solveig M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11-01)
      A key step in the process of isolating microbial natural products is the preparation of an extract from a culture. This step determines which molecules will be available for detection in the subsequent chemical and biological analysis of a biodiscovery pipeline. In the present study we wanted to document potential differences in performance between liquid–liquid extraction using ethyl acetate ...

    • Seasonal and yearly variation of total polyphenols, total anthocyanins and ellagic acid in different clones of cloudberries (Rubus chamaemorus L.) 

      Hykkerud, Anne Linn; Uleberg, Eivind; Hansen, Espen; Vervoort, Marieke; Mølmann, Jørgen; Martinussen, Inger (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-05-02)
      Cloudberry (Rubus chamaemorus L.) is a wild perennial shrub growing on peatland with a circumpolar distribution. The combined berries have a high polyphenol content comprised primarily of ellagitannins. A few commercial cultivars are available, and pre-breeding trials on clonal material from different geographical origins are in progress. The objective of this study was to investigate how the content ...

    • Synthetic analogs of stryphnusin isolated from the marine sponge Stryphnus fortis inhibit acetylcholinesterase with no effect on muscle function or neuromuscular transmission 

      Moodie, Lindon; Zuzek, Monika; Frangez, Robert; Andersen, Jeanette hammer; Hansen, Espen; Olsen, Elisabeth Klungerbo; Cergolj, Marija; Sepcic, Kristina; Hanssen, Kine Østnes; Svenson, Johan (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-11-09)
      The marine secondary metabolite stryphnusin (1) was isolated from the boreal sponge Stryphnus fortis, collected off the Norwegian coast. Given its resemblance to other natural acetylcholinesterase antagonists, it was evaluated against electric eel acetylcholinesterase and displayed inhibitory activity. A library of twelve synthetic phenethylamine analogs, 2a–7a and 2b–7b, containing tertiary and ...

    • The thuEFGKAB Operon of Rhizobia and Agrobacterium tumefaciens Codes for Transport of Trehalose, Maltitol, and Isomers of Sucrose and Their Assimilation through the Formation of Their 3-Keto Derivatives 

      Ampomah, Osei Yaw; Avetisyan, Anna; Hansen, Espen; Svenson, Johan; Huser, Thomas; Jensen, John Beck; Bhuvaneswari, T.V (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      The thu operon (thuEFGKAB) in Sinorhizobium meliloti codes for transport and utilization functions of the disaccharide trehalose. Sequenced genomes of members of the Rhizobiaceae reveal that some rhizobia and Agrobacterium possess the entire thu operon in similar organizations and that Mesorhizobium loti MAFF303099 lacks the transport (thuEFGK) genes. In this study, we show that this operon is ...

    • Two Novel Lyso-Ornithine Lipids Isolated from an Arctic Marine Lacinutrix sp. Bacterium 

      Kristoffersen, Venke; Jenssen, Marte; Raid Jawad, Heba; Isaksson, Johan; Hansen, Espen; Rämä, Teppo; Østnes Hansen, Kine; Andersen, Jeanette Hammer (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-31)
      The Lacinutrix genus was discovered in 2005 and includes 12 Gram-negative bacterial species. To the best of our knowledge, the secondary metabolite production potential of this genus has not been explored before, and examination of Lacinutrix species may reveal novel chemistry. As part of a screening project of Arctic marine bacteria, the Lacinutrix sp. strain M09B143 was cultivated, extracted, ...