An acyl-ACP thioesterase consisting of an amino acid sequence of the 72.sup.nd to 233.sup.rd amino acids set forth in SEQ ID NO: 1, an acyl-ACP thioesterase gene encoding the protein, a transformant having the gene, and a method of producing a lipid using the transformant.

The present description is related to the field of cultivating algae. It introduces a method of cultivating algae by depleting the culture of an inorganic nutrient and exposing the alga to high intensity light to obtain algal cell mass having enriched lipid content and reduced chlorophyll content.

[Problems] To provide a method of producing a lipid, containing enhancing productivity of medium chain fatty acids or the lipid containing these medium chain fatty acids as components.

[Means to solve] A method of producing a lipid, containing the steps of: culturing a transformant in which a gene encoding any one of the following proteins (A) to (C) is introduced into a host, and collecting a lipid from the cultured product: (A) a protein consisting of the amino acid sequence of the 91st to 348th positions set forth in SEQ ID NO: 1; (B) a protein consisting of an amino acid sequence having 80% or more identity with the amino acid sequence of the 91st to 348th positions set forth in SEQ ID NO: 1, and having acyl-ACP thioesterase activity; and (C) a protein containing; the amino acid sequence of the protein (A) or (B), and having acyl-ACP thioesterase activity.

The present invention relates to an acyl-CoA synthetase homolog protein from microorganisms of the genus Mortierella, a polynucleotide encoding the protein, and so on. The invention provides polynucleotides comprising an acyl-CoA synthetase homolog protein gene from, e.g., Mortierella alpina, expression vectors comprising these polynucleotides and transformants thereof, a method for producing lipids or fatty acids using the transformants, food products containing the lipids or fatty acids produced by the method, etc.

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.

A method to increase the biomass production and fatty acids in the alga Chlorella vulgaris Beyerinck and obtain a lipid rich biomass type C:16 (palmitic), C18:1n-9 (oleic), C18:2n-6t (linoleidic) and C18:3n-3 (alpha-linolenic), which uses low irradiance from a dichromatic light source.

An efficient virus based wet biomass lipid extraction system is disclosed herein. The system includes a microalgal biomass which is inoculated with a matched algal virus. The biomass is then incubated under conditions resulting in the algal virus infecting the algae cells and proliferating to the point that the algae cells are disrupted. This releases lipids such that they may be collected by conventional techniques, including solvent extraction. In an exemplary embodiment, the microalgal biomass comprises Chlorella sp, and the virus was Chlorovirus Paramecium bursaria chlorella virus (PBCV-1).

The present invention generally relates to a novel process in which thin stillage is processed to produce algae oil and protein rich biomass as well as other energy rich byproducts. In accordance with a preferred embodiment, thin stillage is removed from an evaporator during the evaporation process to produce mid-stillage. This mid-stillage is preferably routed to a new process where it is directed to a pre-treatment centrifuge to remove suspended solids, sludge and corn oil. Thereafter, the mid-stillage is preferably cooled and then directed to a fermentation tank where the mid-stillage is subject to a batch fermentation process with algae “seed” fed from an algae inoculation system. Once the batch is harvested, the oil-rich algae/mid-stillage is then preferably heated to rupture the cells and liberate the oil. Thereafter, the oil-rich algae/mid-stillage is preferably processed by a centrifuge which produces solids, a light phase oil and a “clean” mid-stillage stream that can be evaporated to a very high level of solids.