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Kaewsuwan S.,Marine Natural Products Research Unit | Bunyapraphatsara N.,Mahidol University | Cove D.J.,Washington University in St. Louis | Quatrano R.S.,Washington University in St. Louis | Chodok P.,Marine Natural Products Research Unit
Bioresource Technology | Year: 2010

Adrenic acid (ADA), an ω-6 polyunsaturated fatty acid (PUFA), has attracted much interest due to its pharmaceutical potential. Exploiting the wealth of information currently available on in planta oil biosynthesis, and coupling this information with the tool of genetic engineering, it is now feasible to deliberately alter fatty acid biosynthetic pathways to generate unique oils in commodity crops. In this study, a Δ5-elongase gene from the algae Pavlova sp. related to the biosynthesis of C22 PUFAs was targeted to enable production of ADA in the moss Physcomitrella patens. Heterologous expression of this gene was under the control of a tandemly duplicate 35S promoter. It was established that ADA (0.42 mg/l) was synthesized in P. patens from endogenous arachidonic acid (ARA) via the expressed Pavlova sp. Δ5-elongase in the moss. In an attempt to maximize ADA production, medium optimization was effected by the response surface methodology (RSM), resulting in a significant elevation of ADA (4.51 mg/l) production under optimum conditions. To the best of our knowledge, this is the first study describing the expression of a PUFA synthesizing enzyme in non-seed lower plant without supplying the exogenous fatty acid. © 2010 Elsevier Ltd. All rights reserved.

Sirirak T.,Marine Natural Products Research Unit | Brecker L.,University of Vienna | Plubrukarn A.,Marine Natural Products Research Unit
Natural Product Research | Year: 2013

An extensive search for the trisoxazole macrolides in the Thai specimen of the sponge Pachastrissa nux led to the isolation of a new kabiramide derivative, kabiramide L (1) and the previously reported kabiramide I (2). Both macrolides had a moderate antiplasmodial activity against Plasmodium falciparum K1 with IC50s of 2.6 and 4.5 M, respectively. To date, P. nux has been the only known source of the trisoxazole macrolides bearing the 30-enone moiety. Both compounds were also added to the list of chemicals postulated to play a defensive role in the P. nux sponge. © 2013 Taylor and Francis Group, LLC.

Chodok P.,Marine Natural Products Research Unit | Kaewsuwan S.,Marine Natural Products Research Unit
JAOCS, Journal of the American Oil Chemists' Society | Year: 2010

Identification of the parameters that had significant effects on polyunsaturated fatty acids (PUFAs) and biomass production by the moss Physcomitrella patens was performed using nine culture variables (temperature, agitation speed, pH, sucrose, di-ammonium tartrate, CaCl22H 2O, MgSO47H2O, KH2PO4 and KNO3) with the statistical design technique of Plackett-Burman. Statistical analysis revealed that two physical variables (pH and temperature) had significant effects on the production of both biomass and PUFAs (linoleic acid, LA; γ-linolenic acid, GLA; α-linolenic acid, ALA; eicosadienoic acid, EDA; di-homo-γ-linolenic acid, DHGLA; arachidonic acid, ARA; eicosapentaenoic acid, EPA). Three nutritional variables (sucrose, CaCl2 and MgSO4) had an influence only on the production of some of the PUFAs. Of the two levels used in this study, higher concentrations of sucrose had a positive effect on LA, ARA and EPA production, whereas higher concentrations of metal ions (CaCl2 and MgSO 4) had a negative effect only on ARA and EPA production. After adjustment by multiple linear regression, it can be concluded that pH, temperature, sucrose, CaCl2 and MgSO4 were the most statistically significant parameters for the growth of P. patens and for PUFA production by this moss. © 2010 AOCS.

Chodok P.,Marine Natural Products Research Unit | Cove D.J.,University of Leeds | Cove D.J.,Washington University in St. Louis | Quatrano R.S.,Washington University in St. Louis | And 2 more authors.
JAOCS, Journal of the American Oil Chemists' Society | Year: 2012

Long chain (C ≥ 20) polyunsaturated fatty acids (LC-PUFAs) represent important components of the human diet. Currently, the predominant sources of these fatty acids are marine fish and algal oils, but high production costs and diminishing feedstock, limit their supply and usage. A more regular sustainable source of these compounds is urgently required and therefore research is being conducted to develop a sustainable, land-based production system. This work describes the metabolic engineering of an artificial pathway that activates the production of C 22-PUFAs, docosatetraenoic acid or adrenic acid (ADA) and n-3 docosapentaenoic acid (DPA) in Physcomitrella patens using a gene from a marine algae Pavlova sp. encoding Δ 5-elongase and vegetable oil supplementation. The accumulation of ADA and ω-3 DPA were dramatically increased to 24.3 and 11.7 mg L -1 and accounted for 2.3 and 1.1% of total fatty acids, respectively. This is the first report on producing n-3 DPA, DHA precursor, in P. patens. The obtained results prove that this enzyme appears to be more active when fused to a green fluorescence protein reporter gene. These finding reveal that the modification of the fatty acid biosynthetic pathway by genetic manipulation and nutritional supplementation, to produce specific PUFAs in a non-seed lower plant, is a promising technique. © AOCS 2011.

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