Process for producing industrial products from plant lipids
The present invention relates to methods of producing industrial products from plant lipids, particularly from vegetative parts of plants. In particular, the present invention provides oil products such as biodiesel and synthetic diesel and processes for producing these, as well as plants having an increased level of one or more non-polar lipids such as triacylglycerols and an increased total non-polar lipid content. In one particular embodiment, the present invention relates to combinations of modifications in two or more of lipid handling enzymes, oil body proteins, decreased lipid catabolic enzymes and/or transcription factors regulating lipid biosynthesis to increase the level of one or more non-polar lipids and/or the total non-polar lipid content and/or mono-unsaturated fatty acid content in plants or any part thereof. In an embodiment, the present invention relates to a process for extracting lipids. In another embodiment, the lipid is converted to one or more hydrocarbon products in harvested plant vegetative parts to produce alkyl esters of the fatty acids which are suitable for use as a renewable biodiesel fuel.
1. A process for producing extracted lipid, the process comprising
i) extracting lipid from plant leaf pieces expressing an exogenous Wrinkled 1 (WRI1) polypeptide and an exogenous diacylglycerol acyltransferase (DGAT), and having reduced triacylglycerol (TAG) lipase activity or expressing an exogenous Leafy Cotyledon 2 (LEC2) polypeptide or both reduced TAG lipase activity and expressing an exogenous LEC2 polypeptide, the leaf pieces having a surface area of at least 1 cm 2 , a total non-polar lipid content of between 5% and 30% by weight on a dry weight basis, and an increased total non-polar lipid content relative to a corresponding leaf piece which expresses the exogenous WRI1 polypeptide and the exogenous DGAT1 polypeptide but which does not have reduced TAG lipase activity and does not express the exogenous LEC2 polypeptide, and
ii) recovering the extracted lipid,
thereby producing the extracted lipid.
2. The process of claim 1 , wherein the leaf pieces in total have a dry weight of at least 2 g.
3. The process of claim 1 in which the volume of the extracted lipid is at least 1 liter.
4. The process of claim 1 , wherein the step of extracting lipid from the leaf pieces comprises one or more of rolling, pressing, crushing or grinding the leaf pieces.
5. The process of claim 1 , wherein the leaf pieces are harvested from one or more plants at a time between about the time of flowering of the plants to about the time senescence of the plants has started.
6. The process of claim 1 , wherein the leaf pieces have reduced TAG lipase activity.
7. The process of claim 6 , wherein the reduced TAG lipase is Sugar Dependent 1 (SDP1) TAG lipase.
8. The process of claim 6 , wherein the leaf pieces do not express exogenous LEC2 polypeptide.
9. The process of claim 1 , wherein the leaf pieces express an exogenous LEC2 polypeptide.
10. A process for producing a plant having leaves with a total non-polar lipid content of between 5% and 30% by weight on a dry weight basis, the process comprising
i) obtaining one or more plants which (1) express an exogenous Wrinkled 1 (WRI1) polypeptide and an exogenous diacylglycerol acyltransferase, and (2) have reduced triacylglycerol (TAG) lipase activity or express an exogenous Leafy Cotyledon 2 (LEC2) polypeptide or have both reduced TAG lipase activity and express an exogenous LEC2 polypeptide, and
ii) selecting a plant which has leaves comprising a total non-polar lipid content of between 5% and 30% by weight on a dry weight basis and which has an increased total non-polar lipid content relative to a corresponding leaf piece which expresses the exogenous WRI1 polypeptide and the exogenous DGAT1 polypeptide but which does not have reduced TAG lipase activity and does not express the exogenous LEC2 polypeptide.
11. The process of claim 10 , further comprising obtaining seed of the plant selected in step ii).
12. The process of claim 10 , further comprising obtaining progeny of the plant selected in step ii).
13. The process of claim 12 , wherein the plant having leaves with a total non-polar lipid content of between 5% and 30% by weight on a dry weight basis has one or more or all of the following features:
i) oleic acid comprises at least 19% of the total fatty acid content in the non-polar lipid in the leaves of the plant,
ii) palmitic acid comprises at least 20% of the total fatty acid content in the non-polar lipid in the leaves of the plant,
iii) linoleic acid comprises at least 15% of the total fatty acid content in the non-polar lipid in the leaves of the plant, and
iv) α-linolenic acid comprises less than 15% of the total fatty acid content in the leaves of the plant.
14. The process of claim 10 , wherein the one or more plants obtained in step i) have reduced TAG lipase activity and express a LEC2 polypeptide.
15. The process of claim 10 , wherein the selected plant obtained in step ii) comprises leaf pieces which comprise reduced TAG lipase.
16. The process of claim 15 , wherein the reduced TAG lipase is Sugar Dependent 1 (SDP1) TAG lipase.
17. The process of claim 10 , wherein the leaf pieces express an exogenous LEC2 polypeptide.
18. The process of claim 12 , comprising obtaining progeny plants for at least two generations from the selected plant of step ii), wherein the progeny plants comprise an increased total non-polar lipid content relative to a corresponding leaf piece which expresses the exogenous WRI1 polypeptide and the exogenous DGAT1 polypeptide but which does not have reduced TAG lipase activity and does not express the exogenous LEC2 polypeptide.