Carrots, chlorogenic acids

Minimal processing of carrots induces phenylalanine ammonia lyase (PAL) activity and phenolics accumulation. In shredded carrots, chlorogenic acid, which is rapidly accumulated, represents 60% of the total phenolics. In addition traces of 3 -caffeoylquinic and 4 -caffeoylquinic acids are biosynthesised, and 3, 4 -dicaffeoylquinic and 3, 5 -dicaffeoyl quinic acids also accumulate [44]. p-Hydroxybenzoic acid derivatives are also biosynthesised but more slowly, and are related to defence against microbial attack (phytoalexin response), the degree and speed of which depends on the cultivar [45],... 

Kuhnl, T., Koch, U., Heller, W., and Wellmann, E., 1987, Chlorogenic acid biosynthesis characterization of a light induced microsomal 5-0-(4-coumaroyl)-D-quinate/shikimate 3 -hydroxylase from carrot (Daucus carota L.) cell suspension cultures, Arch. Biochem. Biophys. 258 226-232. 

Carrots (Duacus carota) contain a range of chlorogenic acids including 3-0-and 5-O-caffeoylquinic acids, 3-0-p-coumaroylquinic acid, 5-O-feruloylquinic acid, and 3,5-O-dicaffeoylquinic acids (Fig. 1.30). These chlorogenic acids are found in almost all varieties of carrot with a 10-fold higher level of 5-O-caffeoylquinic acid in purple carrots [Alasalvar et al., 2001]. 

The majority of swallowtail butterflies of the genus Papilio (family Papilionidae) exclusively utilize plants of the family Rutaceae as hosts, with a few species exploiting limited plant species of the families Apiaceae or Lauraceae. The North American black swallowtail butterfly, Papilio polyxenes, a specialist on members of carrot family (Apiaceae), has already been shown to lay eggs in response to a mixture of two chemotactile stimulants, luteolin 7-0-(6"-0-malonyl)-/3-D-glucoside and trawr-chlorogenic acid, identified from one of its major host plants, Daucus carota (wild carrot). Further study revealed that the oviposition response by the butterfly to another host plant, Pastinaca sativa (wild parsnip), was evoked by a combination of tyramine (1), trans-chlorogenic acid, and a neutral fraction from the plant.4... 

In carrots, the principal phenolics are the hydroxycinnamic acid derivatives. Of these, caffeic acid derivatives are the main components (20-100 mg/kg fw. depending on the cultivar), while ferulic acid derivatives are accumulated in intermediate quantities (10-20 mg/kg) and p-coumaric derivatives, 4-hydroxybenzoic acid derivatives and vanillic acid are present in trace amounts [38]. The main compound in carrots is chlorogenic acid, which has been estimated as between 23 and 121 mg/kg f w. depending on the cultivar. However, in carrot tops, this compound can reach 375-400 mg/kg [40], while cryptochlorogenic, neochlorogenic and 5-feruloylquinic acids have also been detected. 

Oviposition by females of the black swallowtail butterfly, Papilio polyxeneSy was stimulated by tarsal contact with ethanolic extracts of carrot foliage, Daucus carota. Two of the stimulants were identified as -chlorogenic acid and lute-... 

P-coumaric acid and chlorogenic acid—Found in many fruits and vegetables, including tomatoes, green peppers, pineapples, strawberries, and carrots, which prevents the formation of cancer-causing nitrosamines from nitric acids and amines. 

Figure 7.4 Carrots contain carotenoids, chlorogenic acids, phytosterols and the polyacetylene, falcarinol.

Cole, R.A. (1985) Relationship between the concentration of chlorogenic acid in carrot root and the incidence of carrot fly larval damage. Ann. Appl. Biol, 106, 211-217. 

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