Lipase-catalyzed synthesis of two new antioxidants: 4-O- and 3-O-palmitoyl chlorogenic acids

Abstract

Chlorogenic acid (5-caffeoyl quinic acid (CQA)) extracted from Hydrangea macrophylla (44%, w/w) with 98% purity, was acylated with palmitic acid by Novozym 435 to yield mono-acylated CQA. Acylation of CQA was achieved in 2-methyl-2-butanol at 60°C, and yielded two mono-acylated products: a major product acylated at the C-4 of the quinic moiety (4-O-palmitoyl chlorogenic acid) and a minor product acylated at the C-3 (3-O-palmitoyl chlorogenic acid). The bioconversions obtained in 7 days ranged from 14 to 60% and were influenced by the molar ratio of palmitic acid/CQA, which ranged from 10 to 80. The regioselectivity (4-O-palmitoyl/3-O-palmitoyl ratio) of the reaction was also affected by the molar ratio, and ranged from 90 to 70%. The scavenging activities against 1,1-diphenyl-2-picryl-hydrazyl radicals demonstrated that these palmitoyl CQA derivatives are associated with antioxidant activity (70% vs CQA).

A Straightforward Access to New Families of Lipophilic Polyphenols by Using Lipolytic Bacteria

“…Previous reports have shown that the lipophilic derivatives and analogs of one of the olive phenols, HT, with esters or ethers functionalities display a better hydrophilic/lipophilic balance [28], an increased bioavailability compared with their unprotected analogs [29] and stability to oxygen compared with the underivatized HT, which make these molecules more attractive for the food industry [30]. These findings prompted us to develop three innovative aspects.…”

Production and properties of chlorogenic acid lipophilic esters

“…Concerning CQA acyl esters, 4-O-palmitoyl-CQA and 3-O-palmitoyl-CQA display similar free radical scavenging activities, equivalent to 70-80% of CQA activity [7]. Interestingly, activity of CQA acyl esters was as much as five times higher than butylhydroxytoluene activity, a common synthetic antioxidant added to food.…”

“…and palmitic acid in 2methyl-2-butanol using Novozym 435m at 608C [7]. and palmitic acid in 2methyl-2-butanol using Novozym 435m at 608C [7].…”

“…In our laboratory, synthesis of CQA acyl ester was carried out with CQA purified from Hydrangea sp. and palmitic acid in 2methyl-2-butanol using Novozym 435m at 608C [7]. As shown in Figure 2, palmitic acid/CQA molar ratios as high as 80 are needed to reach high synthesis yields.…”

New route for synthesis of 3- and 5-caffeoylquinic acids via protected quinic acids

“…Owing to their antioxidant and other biological effects [6][7][8], convenient methods of CQAs have been sought for practical synthesis. As a result, numerous scientific papers have been published on the chemical and enzymatic synthetic methods, such as by Hemmerle et al [9] and Lorentz et al [10] Among these methods, Sefkow and co-workers' [11,12] have reported for the first time a complete package of CQAs syntheses. They synthesized 1-, 3-, 4-, and 5-CQA with performing esterification of suitable protected quinic acids with acid chloride of caffeic acid.…”