Comparative study of the antioxidant activities of some lipase-catalyzed alkyl dihydrocaffeates synthesized in ionic liquid.
The solubility limitations of phenolic acids in many lipidic environments are now greatly improved by their enzymatic esterification in ionic liquids (ILs). Herein, four different ILs were tested for the esterification of dihydrocaffeic acid with hexanol and the best IL was selected for the synthesis of four other n-alkyl esters with different chain-lengths. The effect of alkyl chain length on the anti-oxidative properties of the resulted purified esters was investigated using β-carotene bleaching (BCB) and free radical scavenging method DPPH and compared with butylated hydroxytoluene (BHT) as reference compound. All four esters (methyl, hexyl, dodecyl and octadecyl dihydrocaffeates) exhibited relatively strong radical scavenging abilities. The scavenging activity of the test compounds was in the following order: methyl ester>hexyl ester⩾dodecyl ester>octadecyl ester>BHT while the order for the BCB anti-oxidative activity was; BHT>octadecyl ester>dodecyl ester>hexyl ester>methyl ester.
Department of Food Technology, University Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Somayeh
S
Gholivand
Department of Food Technology, University Putra Malaysia, 43400 Serdang, Selangor, Malaysia. Electronic address: olaniny56@gmail.com.
Ola
O
Lasekan
Department of Food Technology, University Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Chin Ping
CP
Tan
Department of Food Science, University Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Faridah
F
Abas
Laboratory of Natural Products, Institute of Bioscience, University Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Leong Sze
LS
Wei
D000975:Antioxidants / Q000737:chemistry*; D002084:Butylated Hydroxytoluene / Q000737:chemistry; D002109:Caffeic Acids / Q000737:chemistry*; D002384:Catalysis; D004951:Esterification; D062385:Hydroxybenzoates / Q000737:chemistry; D007477:Ions / Q000737:chemistry*; D008049:Lipase / Q000378:metabolism*; D019207:beta Carotene / Q000737:chemistry
D000975:Antioxidants; D002109:Caffeic Acids; D062385:Hydroxybenzoates; D007477:Ions; D019207:beta Carotene; C000995:3,4-dihydroxyphenylpropionic acid; D002084:Butylated Hydroxytoluene; D008049:Lipase; C017616:phenolic acid
1,1-Diphenyl-2-picryl-hydrazyl (PubChem CID: 24856989); 1-Butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide (PubChem CID: 24887144); 1-Butyl-3-methylimidazoliumhexafluorophosphate (PubChem CID: 24886139); 1-Hexyl-3-methylimidazoliumhexafluorophosphate (PubChem CID: 24889211); 3,4-Dihydroxycaffeic acid (PubChem CID: 24278290); Antioxidant activity; Candida antarctica lipase (Novozyme 435); Dihydrocaffeic acid; Dodecanol (PubChem CID: 8193); Enzymatic esterification; Hexanol (PubChem CID: 8103); Ionic liquid; Linoleic acid (PubChem CID: 5280450); Methanol (PubChem CID: 887)