10-hydroxy-8-octadecenoic acid

Guerrero, A., I. Casals, M. Busquets, Y. Leon, and A. Manresa, Oxidation of Oleic Acid to (E)-10-Hydroperoxy-8-octadecenoic and ( )-10-Hydroxy-8-octadecenoic Acids by Pseudomonas sp. 42A2, Biochim. Biophys. Acta 1347 75-81 (1997). 

In classical sophorolipids known since 1961, a sophorose unit is linked glycosidically to a hydroxyl fatty acid residue, as shown in Fig. 2. The C17 carbon atom of the 17-hydroxy-octadecenoic acid moiety has been determined to be 5-configurated. 

Sulfated Natural Oils and Fats. Sulfated natural triglycerides were the first nonsoap commercial surfactants introduced in the middle of the nineteenth century. Since then sulfates of many vegetable, animal, and fish oils have been investigated (see also Fats AND FATTY oils). With its hydroxyl group and a double bond, ricinoleic acid (12-hydroxy-9,10-octadecenoic acid) is an oil constituent particularly suited for sulfation. Its sulfate is known as turkey-red oil. Oleic acid is also suited for sulfation. Esters of these acids can be sulfated with a minimum of hydrolysis of the glyceride group. Polyunsaturated acids, with several double bonds, lead to dark-colored sulfation products. The reaction with sulfuric acid proceeds through either the hydroxyl or the double bond. The sulfuric acid half ester thus formed is neutralized with caustic soda ... 

Nevertheless, there are some vegetable oils that have a very specific composition. For example, castor oil consists of large amounts (83 89%) of 12-hydroxy-(Z)-9-octadecenoic acid (ricinoleic acid) which is not found in other natural lipids [21]. Ricinoleic acid produces a very characteristic oxidation product, 9,12-dihydroxyoctadecanoic acid [43], and both of these compounds can be considered as specific biomarkers for castor oil and have been used to assess its presence in ceramic lamps [43] and mummification balms [23]. 

Hydroxy-2-phenylethanoic acid Propenoic acid (Z)-9-Octadecenoic acid... 

Ricinoleic acid 18 1 Hydroxy-9-cis-octadecenoic acid Castor oil... 

Figure 31.1. Schematic diagram of the production of 7,10-dihydroxy-8( T)-octadece-noic acid (DOD) from oleic acid by P. aeruginosa PR3. HOD represents 10(S)-hydroxy-8(E)-octadecenoic acid.

Ricinelaidic acid 9-Octadecenoic acid, 12-hydroxy-, [/ -( )]- Veratric acid Benzoic acid, 3,4-dimethoxy-... 

Ricinoleic acid (i -12-hydroxy-9-cw-octadecenoic acid) (Fig. 6) accounts for 80-90% of fatty acids in castor oil (from Ricinus communis). It is found in other plant species and in the sclerotia of the ergot fungus Claviceps purpurea). Lesquerolic acid (i -14-hydroxy-ll-cw-eicosenoic acid), which is a C20 homolog of ricinoleic acid, occurs in Lesquerella species (up to 70% of total fatty acids). Isoricinoleic acid (i -9-hydroxy-12-cw-octadecenoic acid, or 9-OH 18 2 12c) is a major acid in the Wrightia species. In plants, several C16 and C18 mono, di, and trihydroxy fatty acids are stmctural components of cutin (a polyester constituent of plant cuticle). 

Fatty acids with trans or non-methylene-interrupted unsaturation occur naturally or are formed during processing for example, vaccenic acid (18 1 Hr) and the conjugated linoleic acid (CLA) rumenic acid (18 2 9tllc) are found in dairy fats. Hydroxy, epoxy, cyclopropane, cyclopropene acetylenic, and methyl branched fatty acids are known, but only ricinoleic acid (12(/f)-hydroxy-9Z-octadecenoic acid) (2) from castor oil is used for oleochemical production. OUs containing vernolic acid (12(5),13(/ )-epoxy-9Z-octadecenoic acid) (3) have potential for industrial use. 

Scheme 8 Generation of 13-oxo-9,ll-octadecadienoic acid and 13-oxo-9-hydroxy-10-octadecenoic acid.

Of interest is a unique alternative biosynthetic pathway for CLA. Ogawa et al. (2001) reported that a strain of Lactobacillus acidophilus, under micro-aerobic conditions, produced 1O-hydroxy-cA-12-octadcccnoic acid and 10-hydroxy-trans-12-octadecenoic acid as intermediates in the synthesis of cis-9, trans-11 and trans-9, cis-11 18 2. The conversion was induced by presence of linoleic acid, and a high yield of CLA was reported. Hudson et al. (1998, 2000) showed that lactic acid bacteria, including Lactobacillus, Pediococcus, and Streptococcus species, are the major unsaturated fatty acid hydrating bacteria in the rumen, converting oleic acid to 10-hydroxy stearic acid and linoleic acid to 10-hydroxy-12-octadecenoic acid and 13-hydroxy-9 octadecenoic acid. Thus, potentially, CLA may be produced also in the rumen from linoleic acid by pathways other than the classic isomerase described by Kepler et al. (1966). 

A Flavobacterium sp. can be used to hydrate linoleic acid to 10-hydroxy-12(2)octadecenoic acid, an analogue of ricinoleic acid.222 Ricinoleic acid (12-hydroxy-9(.Z)oc-tadecenoic acid) from castor oil is important in the preparation of paints and varnishes.223 Cryptococcus neofor-mans can convert /3-pentadecane to the corresponding a-cu-dicarboxylic acid (HOOC(CH2)i3COOH).224 Toluene can be converted to 4-hydroxybenzoic acid... 

---