Cumic acid

Cumin-dl, n. cumin oil. -samen, m. cumin seed. -sSure, /. cumic acid, cuminic acid. 

Tyrosinase inhibitors prevent browning in foodbecause they inhibit the oxidation caused by the enzyme tyrosinase. Cuminaldehyde is identified as a potent mushroom tyrosinase monophenol monooxygenase inhibitor from cumin seeds, ft inhibits the oxidation of L-3,4-dihydroxyphenylalanine (l-DOPA) by mushroom tyrosinase with an ID50 of 7.7g/ml (0.05 mM). Its oxidized analogue, cumic acid (p-isopropylbenzoic acid), also inhibits this oxidation with an 1D50 of 43g/ml (0.26mM). These two inhibitors affect mushroom tyrosinase activity in different ways (Kubo and Kinst-Hori, 1998). 

Substances discovered by Gerhardt include cumene, cuminol as the aldehyde of cumic acid, and cymene, styrene, anilides, sulphanilic acid, acetanilide, and the anhydrides of monobasic organic acids (1852, see p. 454). He introduced the names phenol, borneol, and glucoside. After Laurent s work on phenol (see p. 389) Gerhardt prepared it by heating salicylic acid with lime and showed that it is not a true acid (acide phenisique) but is related to the alcohols. In his work on anilides he represented oxamide, which the discoverer Dumas had correctly formulated as an amide, + N H, as containing the imide group NH, viz. + = +... 

Cumic acid p-(1-Hydroxy-1-methylethyl)-benzoic acid p-lsopropenylbenzoic acid... 

Pseudomonas sp. strain (PL) was cultivated with p-cymene (178) as the sole carbon source to give cumyl alcohol (192), cumic acid (194), 3-hydroxycumic acid (196), 2,3-dihydroxycumic acid (197), 2-oxo-4-methylpentanoic acid (201), 9-hydroxy-p-cymene (189), and p-cymene-9-oic acid (190) as shown in Figure 19.55 (Madyastha and Bhattacharyya, 1968). On the other hand, p-cymene (178) was converted regiospeci cally to cumic acid (194) by Pseudomonas sp.. Pseudomonas desmolytica, and Nocardia salmonicolor (Madyastha and Bhattacharyya, 1968) (Figure 19.56). 

FIGURE 19.56 Biotransformation of />-cymene (178) to cumic acid (194) by Pseudomonas sp. Pseudomonas desmolytica, and Nocardia salmonicolor. (Modi ed from Yamada, K. et al., Agric Biol. Chem., 29,943,1965 Madyastha, K.M. and Bhattacharyya, P.K., Indian J. Biochem., 5,161,1968- Noma Y. 2000. unpublished data.)... 

Yamada, K., S. Horiguchi, and J. Tatahashi, 1965. Studies on the utilization of hydrocarbons by microorganisms. Part VI. Screening of aromatic hydrocarbon-assimilating microorganisms and cumic acid formation from p cvmene.Agn c. Biol. Chem.. 29 943-948. 

Pseudomonas sp. strain (PL) was cultivated with p-cymene (178) as the sole carbon source to give cumyl alcohol (192), cumic acid (194), 3-hydroxycumic acid (196), 2,3-dihydroxycumic acid (197),... 

The semi-carbazone obtained from cuminol had the same meltii -point the mixture of the two products also melted at 201 to 20 . On oxidation of the aldehyde with moist silver oxide, cumic acid of the melting-point 114 to 116 was obtained a mixture of this acid with pure cumic acid melted at the same temperature. 

Labeled compounds. Cumic acid-7refluxed 8 days with LiAlH4 in ether p-cymene-7- C. Y 71-77%. J.-P. Guermont and L. Pichat, 580. 

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