Processes for producing lipids
The present invention relates to processes for extracting lipid from vegetative plant parts such as leaves, stems, roots and tubers, and for producing industrial products such as hydrocarbon products from the lipids. Preferred industrial products include alkyl esters which may be blended with petroleum based fuels.
1. A process for producing a feedstuff, comprising a step of mixing a vegetative plant part from a transformed plant with at least one other feed ingredient or suitable carrier, the vegetative plant part comprising one or more exogenous polynucleotides which encode at least Wrinkled 1 (WRI1) and a fatty acid acyltransferase selected from the group consisting of: phospholipid:diacylglycerol acyltransferase (PDAT), monoacylglycerol acyltransferase (MGAT), diacylglycerol acyltransferase (DGAT), and glycerol-3-phosphate acyltransferase (GPAT), wherein the vegetative plant part has a total non-polar lipid content of between 5% and 25% (w/w dry weight).
2. The process of claim 1 , wherein the vegetative plant part is a plant leaf.
3. The process of claim 1 , wherein the vegetative plant part has one or more or all of the following features:
a) oleic acid comprises at least 19% of the total fatty acid content in the non-polar lipid in the vegetative plant part,
b) palmitic acid comprises at least 20% of the total fatty acid content in the non-polar lipid in the vegetative plant part,
c) linoleic acid comprises at least 15% of the total fatty acid content in the non-polar lipid in the vegetative plant part, and
d) α-linolenic acid comprises less than 15% of the total fatty acid content in the non-polar lipid in the vegetative plant part.
4. The process of claim 1 , wherein the vegetative plant part has a total non-polar content of at least 10% (w/w dry weight) or at least 11% (w/w dry weight).
5. The process of claim 4 , wherein the vegetative plant part is a plant leaf.
6. The process of claim 2 , wherein the total fatty acid content in the non-polar lipid of the plant leaf comprises at least 2% more oleic acid than the non-polar lipid in a corresponding wild-type plant leaf.
7. The process of claim 2 , wherein the total fatty acid content in the non-polar lipid of the plant leaf comprises at least 2% less palmitic acid than the non-polar lipid in a corresponding wild-type plant leaf.
8. The process of claim 2 , wherein the non-polar lipid of the plant leaf comprises a modified level of total sterols, non-esterified sterols, steroyl esters or steroyl glycosides relative to the non-polar lipid in a corresponding wild-type plant leaf.
9. The process of claim 1 which comprises a step of harvesting the vegetative plant part from a plant grown in the field with a mechanical harvester.
10. The process of claim 9 , wherein the vegetative plant part is harvested from the plant at a time between about the time of flowering of the plant to about the time senescence of the plant has started.
11. The process of claim 1 , wherein the fatty acid acyltransferase comprises a diacylglycerol acyltransferase (DGAT).
12. The process of claim 1 , wherein co-expression of WRI1 and the fatty acid acyltransferase has an effect on non-polar lipid accumulation in the vegetative plant part that is larger than an additive effect of the individual effects of each of WRI1 and the fatty acid acyltransferase expressed alone.
13. The process of claim 1 , wherein the other feed ingredient or suitable carrier comprises one or more of edible fat, carbohydrate, protein, vitamins and minerals.
14. The process of claim 1 , comprising the steps of (i) harvesting vegetative plant parts from at least 100 transformed plants grown in a field, and (ii) mixing the vegetative plant parts with at least one other feed ingredient or suitable carrier, the vegetative plant parts comprising one or more exogenous polynucleotides which encode at least Wrinkled 1 (WRI1) and the fatty acid acyltransferase.
15. A process for producing a feedstuff, comprising the steps of (i) extracting lipid from vegetative plant parts obtained from at least 100 transformed plants grown in a field, the vegetative plant parts comprising one or more exogenous polynucleotides which encode at least Wrinkled 1 (WRI1) and a fatty acid acyltransferase, wherein the vegetative plant parts have an average total non-polar lipid content of between 5% and 25% (w/w dry weight), and (ii) mixing the extracted lipid with at least one other feed ingredient or suitable carrier.
16. A feedstuff produced by the method of claim 1 , comprising the exogenous polynucleotides.
17. A feedstuff produced by the method of claim 14 , comprising the exogenous polynucleotides.
18. The process of claim 2 , wherein the fatty acid acyltransferase comprises a diacylglycerol acyltransferase (DGAT).
19. The process of claim 3 , wherein the fatty acid acyltransferase comprises a diacylglycerol acyltransferase (DGAT).
20. The process of claim 12 , wherein the vegetative plant part is a plant leaf.