TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Method: In the method: the level of expression of the FadR polypeptide in the engineered host cell is increased as compared to the level of expression of the FadR polypeptide in le corresponding wild-type host cell; the level of expression of the FadR polypeptide in the engineered host cell is regulated by an expression control sequence operably linked to a polynucleotide sequence which encodes the FadR polypeptide, where the expression control sequence is a promoter or a ribosome binding site; an ester synthase is over-expressed in the engineered host cell; an acetyl-coenzyme-A carboxylase complex is over-expressed in the engineered host cell, where the acetyl-coenzyme-A carboxylase complex is encoded by at least one acetyl-coenzyme-A carboxylase subunit gene obtained from at least one of Corynebacterium glutamicum, Escherichia coli, Lactococcus lactis, Kineococcus radiotolerans, Desulfovibrio desulfuricans, Erwinia amylovora, Rhodospirillum rubrum, Vibrio furnissii, Stenotrophomonas maltophilia, Synechocystis sp. PCC6803, or Synechococcus elongatus; a biotin protein ligase is overexpressed in the engineered host cell; the fatty acid is a fatty aldehyde or a fatty alcohol, where the carboxylic acid reductase and a thioesterase are over-expressed in the engineered host cell, where the carboxylic acid reductase is carB (SEQ ID NO: 8), and the thioesterase is tesA (SEQ ID NO: 11); an alcohol dehydrogenase is over-expressed in the engineered host cell, where the alcohol dehydrogenase is YjgB (SEQ ID NO: 10) or AlrAadp1; and an a phosphopantetheinyl transferase (PPTase) is over-expressed in the engineered host cell, where the PPTase is EntD from E. coli MG1655 (SEQ ID NO: 12). Preferred Components: The FadR polypeptide: is encoded by a FadR gene obtained from Escherichia, Salmonella, Citrobacter, Enterobacter, Klebsiella, Cronobacter, Yersinia, Serratia, Erwinia, Pectobacterium, Photorhabdus, Edwardsiella, Shewanella or Vibrio; is a wild-type FadR polypeptide or a mutant FadR polypeptide; comprises a mutation at an amino acid residue corresponding to amino acid 219 of SEQ ID NO: 1, where the mutation is a substitution of the amino acid residue corresponding to amino acid 219 of SEQ ID NO: 1 with an asparagine residue; and comprises an amino acid sequence having at least 80% identity to the amino acid sequence of SEQ ID NO: 1. The engineered host cell further comprises an altered level of expression of at least one gene including fabA, fabB, iclR, fadA, fadB, fadD, fadE, fadI, fadJ, fadL, fadM, uspA, aceA, aceB, or aceK as compared to the level of expression of the selected gene(s) in a corresponding wild-type host cell. The ester synthase is: ES9 from Marinobacter hydrocarbonoclasticus (SEQ ID NO: 2); E58 from Marinobacter hydrocarbonoclasticus (SEQ ID NO: 3); AtfAl from Alcanivorax borkumensis SK2 (SEQ ID NO: 4); AtfA2 from Alcanivorax borkumensis SK2 (SEQ ID NO: 5); diacylglycerol-O-acyltransferase from Marinobacter aquaeolei VT8 (SEQ ID NO: 6 or SEQ ID NO: 7) (where the sequences not defined here may be found at ftp://ftp.wipo.int/pub/published_pct_sequences/publication); a wax synthase; or a bifunctional wax ester synthase/acyl-coenzyme-A: diacylglycerol acyltransferase. The host cell is a mammalian cell, plant cell, insect cell, filamentous fungus cell, yeast cell, and bacterial cell, preferably E. coli cell, a Pantoea citrea cell, a Bacillus lentus cell, a Bacillus brevis cell, a Bacillus stearothermophilus cell, a Bacillus lichenformis cell, a Bacillus alcalophilus cell, a Bacillus coagulans cell, a Bacillus circulans cell, a Bacillus pumilus cell, a Bacillus thuringiensis cell, a Bacillus clausii cell, a Bacillus megaterium cell, a Bacillus subtilis cell, a Bacillus amyloliquefaciens cell, a Trichoderma koningii cell, a Trichoderma viride cell, a Trichoderma reesei cell, a Trichoderma longibrachiatum cell, an Aspergillus awamori cell, an Aspergillus fumigatus cell, an Aspergillus foetidus cell, an Aspergillus nidulans cell, an Aspergillus niger cell, an Aspergillus oryzae cell, a Humicola insolens cell, a Humicola lanuginose cell, a Rhodococcus opacus cell, a Rhizomucor miehei cell, a Mucor miehei cell, a Streptomyces lividans cell, a Streptomyces murinus cell, Actinomycetes cell, an Arabidopsis thaliana cell, a Panicum virgatum cell, a Miscanthus giganteus cell, a Zea mays cell, a Botryococcus braunii cell, a Chlamydomonas reinhardtii cell, a Dunaliella salina cell, a Synechococcus sp. PCC 7002 cell, a Synechococcus sp. PCC 7942 cell, a Synechocystis sp. PCC 803 cell, a Thermosynechococcus elongates BP-1 cell, a Chlorobium tepidum cell, a Chloroflexus aurantiacus cell, a Chromatium vinosum cell, a Rhodospirillum rubrum cell, a Rhodobacter capsulatus cell, a Rhodopseudomonas palustris cell, a Clostridium ljungdahlii cell, a Clostridium thermocellum cell, a Penicillium chrysogenum cell, a Pichia pastoris cell, a Saccharomyces cerevisiae cell, a Schizosaccharomyces pombe cell, a Pseudomonas fluorescens cell, a Zymomonas mobilis cell, a Chinese hamster ovary (CHO) cells, a COS cell, a Vero cell, a baby hamster kidney cell, a HeLa cell, a African green monkey kidney cell (Cv1) cell, an Madin-Darby Canine kidney epithelial cells (MDCK) cell, a 293 cell, a 3T3 cell, or a pheochromocytoma-12 cell. The composition has: a fraction of modern carbon (f(M) 14C) of at least 1.003, preferably at least 1.124; and a delta 13C of greater than or equal to (-15.4), preferably (-15.4) to (-10.9). EXAMPLE - No suitable example given.