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Plants producing industrial oils of high quality and low price will facilitate a switch to vegetable oil-based raw materials from the current petroleum-based in the chemical industry. Oils have qualities designed to meet the stringent requirements of the industry, thus it is necessary that they are kept separate from farming of food staples. It is therefore a sensible strategy to develop such production in oil crops dedicated for industrial production. Genes for the special features of the non-food industry oil are missing and must be brought to plants by genetic engineering to improve or develop new crops tailoring the industry's needs. This requires that the crop platforms designated for the industrial oil production will need to be transformable. This review provides an overview of potential non-food oil crops that could become production platforms for oil of industrial quality. It also gives a short state of the art regarding the transformation of these plants producing quality non-food oil.

Our society is highly depending on petroleum for its activities. About 90% is used as an energy source for transportation and for generation of heat and electricity and the remaining as feedstocks in the chemical industry. However, petroleum is a finite source as well as causing several environmental problems such as rising carbon dioxide levels in the atmosphere. Petroleum therefore needs to be replaced by alternative and sustainable sources. Plant oils and oleochemicals derived from them represent such alternative sources, which can deliver a substantial part of what is needed to replace the petroleum used as feedstocks. Plant derived feedstock oils can be provided by two types of oil qualities, multi-purpose and technical oils. Multi-purpose oils represent oil qualities that contain common fatty acids and that can be used for both food and feedstock applications. Technical oil qualities contain unusual fatty acids with special properties gained from their unique molecular structure and these types of oils should only be used for feedstock applications. As a risk mitigation strategy in the selection of crops, technical oil qualities should therefore preferably be produced by oil crop platforms dedicated for industrial usage. This review presents a short survey of oil crop platforms to be considered for either multi-purpose or technical oils production. Included among the former platforms are some of the major oil crops in cultivation such as oil palm, soybean and rapeseed. Among the later are those that could be developed into dedicated industrial platforms such as crambe, flax, cotton and Brassica carinata. The survey finishes off by highlighting the potential of substantial increase in plant oil production by developing metabolic flux platforms, which are starch crops converted into oil crops.

Very long chain primary alcohols are significant components in cuticle waxes of plants. Fatty acyl-CoA reductases (FARs) catalyze the formation of a fatty alcohol from an acyl-CoA. The Arabidopsis (Arabidopsis thaliana) genome contains eight genes homologous to FAR genes from jojoba (Simmondsia chinensis), silk moth, wheat and mouse. Expression of six Arabidopsis FAR homologs in Escherichia coli resulted in production of alcohols from endogenous E. coli fatty acids by five of these genes, confirming that they encode for FAR enzymes. Only a truncated splicing version of the sixth gene was found, and this gene yielded a protein with no FAR activity. The five functional FAR enzymes yielded distinctly different compositions of fatty alcohols when expressed in E. coli, indicating that the different enzymes may be involved in the production of different types of alcohols in plant cells.

Acylation of fatty acids to hydroxy groups in cells generally require activation to a thioester (ACP or CoA) or transacylation from another oxygen ester. We now show that microsomal membranes from Arabidopsis leaves efficiently acylate free fatty acids to long chain alcohols with no activation of the fatty acids to thioesters prior to acylation. Studies of the fatty alcohol and fatty acids specificities of the reaction in membranes from Arabidopsis leaves revealed that long chain (C18-C24) unsaturated fatty alcohols and C18-C22 unsaturated fatty acids were preferred. Microsomal preparations from Arabidopsis roots and leaves and from yeast efficiently synthesized ethyl esters from ethanol and free fatty acids. This reaction also occurred without prior activation of the fatty acid to a thioester. The results presented strongly suggest that wax ester and ethyl ester formation are carried out by separate enzymes. The physiological significance of the reactions in plants is discussed in connection to suberin and cutin synthesis. The results also have implication regarding the interpretation of lipid metabolic experiments done with microsomal fraction.

Oil content and fatty acid composition are important attributes desirable in oil crops. A 3-year (2002–2004) field evaluation of selected East African sesame accessions was conducted in Busia district in Kenya to assess the variability in the seed oil content, fatty acid composition and relationship between oil content and specific fatty acids. The correlations among different fatty acids and oil content were examined to create an understanding of their interrelations for future breeding. The oil content and the concentration of most of the fatty acids examined was significantly different among accessions. However, the concentration of palmitoleic, behenic and erucic acids was similar for all sesame accessions. The oil and fatty acid content varied significantly among the years. However, erucic acid content did not vary with years. Stearic, linolenic and arachidic acid contents were the least affected across the years. Oil content correlated negatively with palmitic and linoleic acids, and positively with stearic and oleic acids. The present 3-year study has identified sesame accessions with consistent oil content as well as those with low or high variation in the levels of oleic and linoleic fatty acids. These accessions, after additional evaluation in multi-location trials, could be suitable for incorporation into coming breeding programs in East Africa targeting an increase in the diversity of the sesame oil quality as well as oil content.

Genetically engineered plants of Arabidopsis thaliana containing either the Crepis alpina linoleate delta 12-acetylenase gene, the Crepis palaestina linoleate delta 12-epoxygenase gene under transcriptional control of a napin promoter or a Lesquerella fendleri oleate hydroxylase under the transcriptional control of the endogenous promoter were analysed for the distribution of fatty acids. Seed samples were analysed from 9 to 23 days after pollination (DAP) as well as mature seeds. The relative amount of oleate was higher and the amount of the polyunsaturated fatty acids was lower in the seeds of the transgenic plants expressing the fatty acid modifying genes than in seeds from the control plants. The degree of the changes was more pronounced in phosphatidylcholine (PC) than in the neutral fraction and varied considerably between the transgenic plants carrying the different genes. The unusual fatty acids (acetylenic, epoxy and hydroxy fatty acids) produced in the transgenic A. thaliana plants accumulated in significant amounts in seed phospholipids during seed development. Despite that the percentage of the unusual fatty acids accumulated in neutral lipids in the transgenic plants were 5–35 times less than in the wild plant species accumulating these acids, the relative levels of these acids in PC were approximately the same (epoxy and hydroxy fatty acids) or much higher (acetylenic fatty acids) than in that lipid in the wild plants. Since ricinoleic, vernolic and crepenynic acid are formed from precursor fatty acids esterified in PC catalysed by delta 12-desaturase like enzymes, it can be concluded that A. thaliana seeds have less efficient mechanisms for the specific channelling of these fatty acids from PC to triacylglycerol (TAG).

Thirteen broods of Ostrea edulis larvae from four specific broodstock treatments were analysed for growth, mortality and fatty acid composition. Larvae from different broodstock treatments, reared under the same standard hatchery conditions with identical diets for 12 days, showed different growth rates but mortality was similar. Growth rates ranged from 1.4 to 5.9 μm per day. Growth rate was significantly related to the content of total polyunsaturated fatty acids (PUFAs) and 22:6 n − 3 fatty acids in newly released larvae. The content of 22:6 n − 3 from different broodstocks explained 50% of the variation in growth rate among broods. However the content of PUFA and the 22:6 n − 3 fatty acid did not differ among broodstock treatments. It is suggested that a fast assay for essential PUFA like 22:6 n − 3 may significantly improve management of commercial bivalve hatcheries.