Microbial Oils and Fatty Acids: Effect of Carbon Source on Docosahexaenoic Acid (C22:6 N-3, Dha) Production by Thraustochytrid Strains

Abstract

Thraustochytrids are marine protists found throughout the world in estuarine and marine habitats. These microorganisms have attracted interest, because their lipids contain different long chain polyunsaturated fatty acids (PUFAs). Those able to produce docosahexaenoic acid (C22:6 n-3, DHA) are the most studied because of the physiological importance of this PUFA in human beings. Their heterotrophic cultivation offers several challenges since biomass, lipid content, and fatty acid profile are dependent on growth conditions. In this work the effects of C source and its concentration on DHA production by different thraustochytrid strains are reviewed. Results obtained by different investigators on the use of alternative and low cost nutrient sources for production of DHA by thraustochytrids are also presented.

IMPROVED PREDICTION FOR MEDIUM OPTIMIZATION USING FACTORIAL SCREENING FOR DOCOSAHEXAENOIC ACID PRODUCTION BY <i>SCHIZOCHYTRIUM</i> SP. SW1

“…Glucose was chosen as the main carbon source based on the results of reported studies where it is proven that glucose serves as the best carbon source for biomass, lipid and DHA accumulation for most Traustochytrids (Shene et al, 2010). However, in contrast to the general understanding that glucose concentration is directly related to biomass accumulation, this component was found to be statistically insignificant in affecting the final biomass concentration of Schizochytrium sp.…”

“…The present largest and richest commercial source of DHA is cold water fatty fish, such as salmon, sardine, anchovy, tuna and cod which can produce up to 30% of DHA and EPA (Vazhappilly and Chen, 1998). In fish oils, both composition and quantity of PUFA depend on the species and other external factors (Shene et al, 2010). In addition, fish oil usually contains considerable amounts of highly saturated fatty acids and its PUFA profile is Science Publications…”

PRODUCTION OF DOCOSAHEXAENOIC ACID (DHA) FROM Thraustochytrium sp. ATCC 26185 USING DIFFERENTS NITROGEN CONCENTRATIONS

“…This accumulation can be due to the low content of nitrogen supply over time. According to Shene et al (2010), a limited amount of substrate favors the accumulation of lipids by oleaginous microorganisms. Ganuza and Izquierdo (2007) observed that the greatest accumulation of fatty acids in the biomass of Schizochytrium sp.…”

“…Thus, when the microorganism multiplies, the nitrogen source is rapidly exhausted, but it continues assimilating the carbon source that is channeled directly to the synthesis of lipids (RATLEDGE and WYNN, 2002). However, culture conditions involving low concentration of nitrogen decrease the cell growth reducing lipids and DHA yield (SHENE et al, 2010).…”

Screening and Characterization of Oleaginous Fungi from Irish Soil for Growth under Low Carbon Substrates

“…The number of oleaginous microorganisms currently in use for energy production is limited; for example, of the 600 yeasts only 25% are known to produce lipids and among 60,000 fungal species less than 50% are known to accumulate lipids (7). Although the numbers seem large, the number of oleaginous microorganisms in use is limited, since the microbial lipid production research and application until now is focused on production of special lipids rich in poly unsaturated fatty acids (such as gamma linolenic acid and arachidonic acid) (1,(8)(9)(10)(11)(12). Oleaginous fungi used for these special lipids production are mainly cultures belonging to…”