Antioxidant Properties of Chlorogenic Acid and Its Alkyl Esters in Stripped Corn Oil in Combination with Phospholipids and/or Water

Abstract

In bulk oil, it is generally thought that hydrophilic antioxidants are more active than lipophilic antioxidants. To test this hypothesis, the antioxidant activity of phenolics with increasing hydrophobicity was evaluated in stripped corn oil using both conjugated diene and hexanal measurements. Chlorogenic acid and its butyl, dodecyl, and hexadecyl esters were used as model phenolic antioxidants with various hydrophobicities. Results showed that hydrophobicity did not correlate well with antioxidant capacity. The combination of chlorogenic acid derivatives with dioleoylphosphatidylcholine (DOPC) and/or water was also studied to determine if the physical structure in the oil affected antioxidant activity. DOPC alone made hexadecyl chlorogenate a less effective antioxidant, but it did not change the antioxidant capacity of chlorogenic acid. In contrast, the combination of DOPC and water (∼400 ppm) renders chlorogenic acid a less active antioxidant, whereas it does not change the activity of hexadecyl chlorogenate. These results show, in bulk oil, that intrinsic parameters such as the hydrophobicity of lipophilized phenolics do not exert a strong influence on antioxidant capacity, but they can be highly influential if potentialized by extrinsic factors such as physical structures in the oil.

Comparison of Antioxidant Evaluation Assays for Investigating Antioxidative Activity of Gallic Acid and Its Alkyl Esters in Different Food Matrices

“…As illustrated in Figure , the result indicated that antioxidant performances of gallic acid and its alkyl esters in bulk soybean oil were independent of polarities. This result was in agreement with the study on chlorogenic acid and its alkyl esters which hydrophobicity did not exert a strong influence on antioxidant capacity . It is worth mentioning that there might be some other minor components and water remaining in soybean oil.…”

Comparison of Antioxidant Evaluation Assays for Investigating Antioxidative Activity of Gallic Acid and Its Alkyl Esters in Different Food Matrices

“…As illustrated in Figure , the result indicated that antioxidant performances of gallic acid and its alkyl esters in bulk soybean oil were independent of polarities. This result was in agreement with the study on chlorogenic acid and its alkyl esters which hydrophobicity did not exert a strong influence on antioxidant capacity . It is worth mentioning that there might be some other minor components and water remaining in soybean oil.…”

Partitioning and antioxidative effect of protocatechuates in soybean oil emulsions: Relevance of emulsifier concentration

“…They hypothesized that negligible antioxidant effect found in emulsions might be attributable to a differential incorporation of the antioxidants in the oil, aqueous and interfacial regions of the emulsion droplets; however, they did not report on their distributions. Similar results were reported by Laguerre et al for chlorogenic acid and its alkyl esters in bulk stripped corn oil. They showed that AO efficiency of the chlorogenic acids is not influenced of hydrophobicity of AO in contrast to the results obtained in corn oil with phospholipids and/or water.…”

Effect of combinations of 3,4‐dihydroxyphenylacetic acid and its esters on the oxidative stability of fish oil–containing trace water

“…The trend observed is similar to the study on chlorogenic acid and its esters in stripped corn oil by Villeneuve et al. [ 19 ] This implies the vital role of minor components in regulating oxidation in a bulk oil system. These surface‐active agents can form association colloids in the presence of water, which act as sites of oxidation.…”

“…The presence of trace water did not affect the antioxidative capacity of the native 3,4-DHPA, whereas there was a significant increase in lipophilic esters and their combinations (Figure 4). The trend observed is similar to the study on chlorogenic acid and its esters in stripped corn oil by Villeneuve et al [19] This implies the vital role of minor components in regulating oxidation in a bulk oil system. These surface-active agents can form association colloids in the presence of water, which act as sites of oxidation.…”

Comparison of Antioxidant Evaluation Assays for Investigating Antioxidative Activity of Gallic Acid and Its Alkyl Esters in Different Food Matrices

“…As illustrated in Figure , the result indicated that antioxidant performances of gallic acid and its alkyl esters in bulk soybean oil were independent of polarities. This result was in agreement with the study on chlorogenic acid and its alkyl esters which hydrophobicity did not exert a strong influence on antioxidant capacity . It is worth mentioning that there might be some other minor components and water remaining in soybean oil.…”

Partitioning and antioxidative effect of protocatechuates in soybean oil emulsions: Relevance of emulsifier concentration

“…They hypothesized that negligible antioxidant effect found in emulsions might be attributable to a differential incorporation of the antioxidants in the oil, aqueous and interfacial regions of the emulsion droplets; however, they did not report on their distributions. Similar results were reported by Laguerre et al for chlorogenic acid and its alkyl esters in bulk stripped corn oil. They showed that AO efficiency of the chlorogenic acids is not influenced of hydrophobicity of AO in contrast to the results obtained in corn oil with phospholipids and/or water.…”

Effect of combinations of 3,4‐dihydroxyphenylacetic acid and its esters on the oxidative stability of fish oil–containing trace water

“…The trend observed is similar to the study on chlorogenic acid and its esters in stripped corn oil by Villeneuve et al. [ 19 ] This implies the vital role of minor components in regulating oxidation in a bulk oil system. These surface‐active agents can form association colloids in the presence of water, which act as sites of oxidation.…”

“…The presence of trace water did not affect the antioxidative capacity of the native 3,4-DHPA, whereas there was a significant increase in lipophilic esters and their combinations (Figure 4). The trend observed is similar to the study on chlorogenic acid and its esters in stripped corn oil by Villeneuve et al [19] This implies the vital role of minor components in regulating oxidation in a bulk oil system. These surface-active agents can form association colloids in the presence of water, which act as sites of oxidation.…”

Comparison of Antioxidant Evaluation Assays for Investigating Antioxidative Activity of Gallic Acid and Its Alkyl Esters in Different Food Matrices

“…As illustrated in Figure , the result indicated that antioxidant performances of gallic acid and its alkyl esters in bulk soybean oil were independent of polarities. This result was in agreement with the study on chlorogenic acid and its alkyl esters which hydrophobicity did not exert a strong influence on antioxidant capacity . It is worth mentioning that there might be some other minor components and water remaining in soybean oil.…”

Partitioning and antioxidative effect of protocatechuates in soybean oil emulsions: Relevance of emulsifier concentration

“…They hypothesized that negligible antioxidant effect found in emulsions might be attributable to a differential incorporation of the antioxidants in the oil, aqueous and interfacial regions of the emulsion droplets; however, they did not report on their distributions. Similar results were reported by Laguerre et al for chlorogenic acid and its alkyl esters in bulk stripped corn oil. They showed that AO efficiency of the chlorogenic acids is not influenced of hydrophobicity of AO in contrast to the results obtained in corn oil with phospholipids and/or water.…”

Effect of combinations of 3,4‐dihydroxyphenylacetic acid and its esters on the oxidative stability of fish oil–containing trace water

“…The trend observed is similar to the study on chlorogenic acid and its esters in stripped corn oil by Villeneuve et al. [ 19 ] This implies the vital role of minor components in regulating oxidation in a bulk oil system. These surface‐active agents can form association colloids in the presence of water, which act as sites of oxidation.…”

“…The presence of trace water did not affect the antioxidative capacity of the native 3,4-DHPA, whereas there was a significant increase in lipophilic esters and their combinations (Figure 4). The trend observed is similar to the study on chlorogenic acid and its esters in stripped corn oil by Villeneuve et al [19] This implies the vital role of minor components in regulating oxidation in a bulk oil system. These surface-active agents can form association colloids in the presence of water, which act as sites of oxidation.…”