Chlorogenic acid biological activities

The remaining shlklmates in Table III also are relatively simple, well known compounds. The phenolic structures of vanillin (125) and gallic acid (127) and the prephenolic structures of the common quinic acid (128) and chlorogenic acid (129) make them candidates for physiological activity. Gallic acid is the monomer for tannins, biological polymers found in the cotton plant (15, 37). 

Skin depigmentation effect. Extract of the dried seed, administered externally to adults at a dose of 5%, was active. Skin-lightening cosmetics contained extract of Coffea arabica seeds (containing chlorogenic acid) as melanin-formation inhibitors. The extract has been incorporated into cosmetics for skin-aging prevention or into hair preparations for hair protection. Biological activity reported has been patented . 

ABSORPTION, METABOLISM AND BIOLOGICAL ACTIVITIES OF CHLOROGENIC ACIDS AND RELATED... 

We comprehensively summarized chlorogenic acids and related compounds in absorption, metabolism and biological activity. Chlorogenic, caffeic and quinic acids are well absorbed in humans and rats. Metabolic transformations of chlorogenic acids in the human system may be crucial for their biological effect. 

Chlorogenic acids are ubiquitously distributed in plants. These compounds are considered to be the active principles in many medicinal plants. They may be constantly taken as food and beverage, and play a role in human health. Here we review the biological effects of chlorogenic acids in this section. 

As described above, chlorogenic acid and DCQAs are widely present in various plants. It is likely that many of the alleged effects of medicinal plants are linked to the functions of their constituents. In this context, several plants have been investigated for their biological activities and their active substances. This section briefly outlines the occurrence and role of chlorogenic acids in medicinal plants. 

Despite the abundance of biological data demonstrating antioxidant activities of chlorogenic acids, the controversy whether these compounds are potent antioxidants or pro-oxidants, remains. The pro-oxidant characteristics of chlorogenic and caffeic acids have been suggested in the several papers [44, 52, 117-121],... 

Chlorogenic acids are shown to have some desirable biological activities. Most of their property relates to their function as antioxidants, evidenced by their activity to scavenge free radicals, to inhibit the formation of free radicals, and to block the oxidation reaction. However, other activities based on mechanisms other than scavenging capacity cannot be ignored. Also, further tests for the in vivo bioactivity of chlorogenic acids are to be needed. However, it is expected that chlorogenic acids may be beneficial to human health. 

However, not all related species or conspecific populations respond similarly under the same UV influence. For example, Betula pendula and B. resinifera, two closely related birch species collected from populations in Europe and Alaska, generally produce a number of flavonoids, hydroxycinnamic acids, and condensed tannins in larger quantity in exposed leaves to artificial UV-B photon fluxes (4.9 kJ m d for 3 hr/day of biologically active radiation) than in non radiated plants (Lavola, 1997). In B. pendula populations the major increase was in flavonoid synthesis but in B. resinifera the bias was towards the hydroxycinnamic acids and condensed tannins. Besides, allopatric (geographically distant) populations of birch reacted differently in the synthesis of specific compounds. For example, chlorogenic acid increased by 22 and 92% in plants from Germany and Alaska, respectively, but in Finnish plants there was no increment at all. 

Chlorogenic acids can be either beneficial or detrimental to biological processes depending on the conditions. In vitro, they have scavenging activities and an inhibitory effect on conjugated... 

Apart from the biological activities of caffeine, those of chlorogenic acid (which is present in substantial quantities in coffee) should not he ignored, as chlorogenic acid is reported to have stimulant, diuretic, and choleretic properties (see artichoke and honeysuckle)-, it also has allergenic properties (morton 3). 

Some of the biological activities are due to chlorogenic acid and saponins. In addition, chlorogenic acid inhibited nitrosation in vitro and in vivo in rats inhibited tumor formation in experimental animals and also has central stimulant effects in mice and rats when administered per os, effect... 

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