The present invention relates to methods of synthesizing long-chain polyunsaturated fatty acids, especially eicosapentaenoic acid, docosapentaenoic acid and docosahexaenoic acid, in recombinant cells such as yeast or plant cells. Also provided are recombinant cells or plants which produce long-chain polyunsaturated fatty acids. Furthermore, the present invention relates to a group of new enzymes which possess desaturase or elongase activity that can be used in methods of synthesizing long-chain polyunsaturated fatty acids. In particular, the present invention provides ω3 destaurases, Δ5 elongases and Δ6 desaturases with novel activities. Also provided are methods and DNA constructs for transiently and/or stably transforming cells, particularly plant cells, with multiple genes.

Provided herein are methods of culturing a microorganism. The methods include providing a container comprising one or more microorganisms in a medium, which has a first carbon to nitrogen ratio; culturing the microorganisms until the culture reaches a threshold indicator; harvesting a portion of the culture while maintaining the majority of the culture in the container; and adding fresh medium comprising a second carbon to nitrogen ratio to the container with the majority of the culture comprising the microorganisms.

Provided herein are methods of culturing a microorganism. The methods include providing a container comprising one or more microorganisms in a medium, which has a first carbon to nitrogen ratio; culturing the microorganisms until the culture reaches a threshold indicator; harvesting a portion of the culture while maintaining the majority of the culture in the container; and adding fresh medium comprising a second carbon to nitrogen ratio to the container with the majority of the culture comprising the microorganisms.

The current invention provides use of a CLA-producing bacterium for the in vivo conversion in the gut of polyunsaturated fatty acids to CLA. The CLA-producing bacterium is selected from one or more of the group consisting of propionibacteria, lactobacilli, lactococci and streptococci, and bifidobacteria.

The present invention relates to polynucleotides from Ostreococcus lucimarinus which code for desaturases and elongases and which can be employed for the recombinant production of polyunsaturated fatty acids. The invention furthermore relates to vectors, host cells and transgenic nonhuman organisms which comprise the polynucleotides, and to the polypeptides encoded by the polynucleotides. Finally, the invention also relates to production processes for the polyunsaturated fatty acids and for oil, lipid and fatty acid compositions.

Process for enriching microalgal biomass, in particular of the genus Nannochloropsis, with different polyunsaturated fatty acids, primarily docosahexaenoic acid (22:6 n-3, DHA), using oils that are rich in these fatty acids. The process comprises the following steps: Preparing a solution or an emulsion of lipids+emulsifying agent (BSA), Preparing the biomass concentrate to obtain a final concentration of mg/ml or greater, Enriching the biomass concentrate by adding the lipids or the emulsion thereof to the microalgal concentrate, Allowing the mixture to rest under constant stirring for at least 24 hours under lighting conditions.

The process allows for the simultaneous enrichment of microalgal biomass of the genus Nannochloropsis with eicosapentaenoic acid (20:5 n-3) (EPA) and docosahexaenoic acid (22:6 n-3) (DHA), to obtain a minimum EPA:DHA weight ratio of 10:1, with an EPA content of at least 10% of the total fatty acid content.

A method of directly microbially converting a plant oil, an animal fat, free fatty acid, or a combination thereof to wax esters includes growing a yeast or bacterial strain in a medium comprising the plant oil, the animal fat, the free fatty acid, or combination thereof, under conditions suitable to produce the wax esters, wherein the yeast or bacterial strain is engineered to express a FAR gene encoding fatty acid alcohol reductase and a WS gene encoding a wax ester synthase, and optionally isolating the produced wax esters. Similar methods of directly microbially converting a plant oil, an animal fat, free fatty acid, or a combination thereof to omega-3 fatty acids by growing a microorganism in a medium comprising the plant oil, the animal fat, the free fatty acid, or combination thereof, under conditions suitable to produce omega-3 fatty acids are also described.

The present invention is directed to isolated microorganisms as well as strains and mutants thereof, biomasses, microbial oils, compositions, and cultures; methods of producing the microbial oils, biomasses, and mutants; and methods of using the isolated microorganisms, biomasses, and microbial oils.

Disclosed is a method for culture of microalgae, advantageously of the genus Crypthecodinium having a gene coding for the small 18s ribosomal RNA subunit having a genetic similarity of at least 96% with the same gene of the strain of the species Crypthecodinium cohnii deposited in the CCAP (Culture Collection of Algae and Protozoa) under number CCAP 1104/3 in a defined chemical medium.

Provided herein are methods of recovering oil from microorganisms. The methods are useful, for example, in obtaining nutritional oils and/or lipid biofuels. The methods of recovering oil described herein include contacting a population of microorganisms with one or more enzymes under conditions that cause disruption of the microorganisms, concentrating the disrupted microorganisms, and extracting lipids from the disrupted microorganisms at high temperature in the presence of a salt and in the absence of solvent.