Bioactive Compounds and Antioxidant Activities of Thyme-Enriched Refined Corn Oil

Authors
1 Laboratory of Bioactive Substances, Biotechnology Center in Borj-Cedria Technopol, BP. 901, 2050 Hammam-Lif, Tunisia.
2 Laboratory of materials molecules and applications, IPEST, BP51 – 2078, La Marsa, Tunisia.
Abstract
This study was designed to examine bioactive compounds of the thyme-enriched corn oil and to determine the antioxidant activity of its methanolic extract. Volatile compounds composition was investigated by Gas Chromatography-Mass Spectrometry (GC-MS), whereas phenolic compounds analysis was performed by Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC). Antioxidant activities of the flavoured oil methanolic extract were evaluated using DPPH radical scavenging, β-carotene-linoleic acid bleaching, reducing power and total antioxidant assays. Flavoured oil major volatiles were p-cymene (26.47%), α-thujene (24.06%) and γ-terpinene (14.30%). Its methanolic extract had higher Total Phenol Contents (TPCs) (53.99 mg 100 g-1) than that of the crude oil (23.63 mg 100 g-1). Thymol was the main phenolic compound in the flavoured oil (55.84%). Flavoured oil methanolic extract showed higher total antioxidant activity (185.22 mg Gallic Acid Equivalent (GAE) 100 g-1) than that of the crude one (100.66 mg GAE 100 g-1). In β-carotene-linoleic acid bleaching and DPPH radical scavenging assays, flavoured oil methanolic extract showed higher activities than that of the crude oil based on IC50values. Flavoured and crude oils were characterized by a close CE50values (1.81 and 1.85 mg mL-1, respectively). Antioxidant activities of the thyme-enriched oil were mainly due to the presence of phenolic compounds such as thymol and hydrocarbons such as γ-terpinene and p- cymene. The thyme-enriched oil could be considered as a new and natural source of antioxidant.

Keywords


1. Abramovic, H. and Abram, V. 2006. Effect of Added Rosemary Extract on Oxidative Stability of Camelina sativa Oil. Acta Agric. Slov., 87(2): 255-261.
2. Adams, R. P. 2001. Identification of Essential Oil Components by Gas Chromatography/ Quadrupole Mass Spectroscopy. Allured, Carol Stream, IL, USA.
3. Ali, R. F. M. 2010. Improvement Stability of Fried Sunflower Oil by Using Different Levels of Pomposia (Syzyygium Cumini). Elec. J. Environ. Agric. Food Chem., 9(2): 396-403.
4. Baccouri, O., Guerfel, M., Baccouri, B., Cerretani, L., Bendini, A., Lercker, G., Zarrouk, M. and Daoud Ben Miled, D. 2008. Chemical Composition and Oxidative Stability of Tunisian Monovarietal Virgin Olive Oils with Regard to Fruit Ripening. Food Chem., 109: 743–754.
5. Bede, E. N. and Chigbu, C. U. 2007. Stability and Acceptability of Spiced Palm Oil. J. Food Technol., 5: 242–245.
6. Bensmira, M., Jiang, B., Nsabimana, C. and Jian, T. 2007. Effect of Lavender and Thyme Incorporation in Sunflower Seed Oil on Its Resistance to Frying Temperatures. Food Res. Int., 40: 341-346.
7. Bouaziz, M., Fki, I., Jemai, H., Ayadi, M. and Sayadi, S. 2008. Effect of Storage on Refined and Husk Olive Oils Composition: Stabilization by Addition of Natural Antioxidants from Chemlali Olive Leaves. Food Chem., 108: 253–262.
8. Bounatirou, S., Smiti, S., Miguel, M. G., Faleiro, L., Rejeb, M. N., Neffati, M., Costa, M. M., Figueiredo, A., Barroso, J. G. and Pedro, L. G. 2007. Chemical Composition Antioxidant and Antibacterial Activities of the Essential Oils Isolated from Tunisian Thymus capitatus Hoff et Link. Food Chem., 105: 146-155.
9. Bourgou, S., Ksouri, R., Bellila, A., Skandrani, I., Falleh, H. and Marzouk, B. 2008. Phenolic Composition and Biological Activities of Tunisian Nigella sativa L. Shoots and Roots. C. R. Biol., 331: 48–55.
10. Dhifi, W., Maalaoui, B., Zitouni, B. and Marzouk, B. 2002. Influence du Système d’Extraction sur la Qualité Organoleptique de L’huile d’Olive de Tunisie. Riv. Ital. Sostanze Gr., 44: 245-249.
11. Farhoosh, R., Einafshar, S. and Sharayei, P. 2009. The Effect of Commercial Refining Steps on the Rancidity Measures of Soybean and Canola Oils. Food Chem., 15: 931–936.
12. Giordani, R., Hadef, Y. and Kaloustian, J. 2008. Compositions and Antifungal Activities of Essential Oils of Some Algerian Aromatic plants. Fitoterapia, 79: 199-203.
13. Hanato, T., Kagawa, H., Yasuhara, T. and Okuda, T. 1988. Two New Flavonoids and Other Constituents in Licorice Root: Their Relative Astringency and Radical Scavenging Effect. Chem. Pharm. Bull., 36: 1090–1097.
14. Hazzit, M., Baaliouamer, A., Veríssimo, A. R., Faleiro, M. L. and Miguel, M. G. 2009. Chemical Composition and Biological Activities of Algerian Thymus Oils. Food Chem., 116: 714–721.
15. Jabri Karoui, I., Aidi Wannes, W. and Marzouk. B. 2010. Refined Corn Oil Aromatization by Citrus aurantium Peel Essential Oil. Ind. Crop. Prod., 32: 202–207.
16. Jabri Karoui, I., Bettaieb, I., Msaada, K., Hammami, M. and Marzouk, B. 2012. Research on the Phenolic Compounds and Antioxidant Activities of Tunisian Thymus capitatus. J. Funct. Food., 4: 661-669.
17. Jabri Karoui, I., Dhifi, W., Ben Jemia, M. and Marzouk, B. 2011. Thermal Stability of Corn Oil Flavoured with Thymus capitatus under Heating and Deep-frying Conditions. J. Sci. Food Agric., 91: 927–933.
18. Jordán, M. J., Martınez, R. M., Martınez, C., Monino, I. and Sotomayor, J. A. 2009. Polyphenolic Extract and Essential Oil Quality of Thymus zygis ssp. Gracilis Shrubs Cultivated under Different Watering Levels. Ind. Crop. Prod., 29: 145–153.
19. Koleva, I. I., Teris, A. B., Jozef, P. H., Linssen, A. G. and Lyuba, N. E. 2002. Screening of Plant Extracts for Antioxidant Activity: A Comparative Study on Three Testing Methods. Phytochem. Anal., 13: 8–17.
20. Kumaran, A. and Karunakaran, R. J. 2007. In vitro Antioxidant Activities of Methanol Extracts of five Phyllanthus Species from India. Food Sci. Technol., 40: 344–352.
21. Mau, J. L., Chao, G. R. and Wu, K. T. 2001. Antioxidant Properties of Methanolic Extracts from Several Ear Mushrooms. J. Agric. Food Chem., 49: 5461–5467.
22. Miguel, G., Simoes, M., Figueiredo, A.C., Barroso, J. G., Pedro, L. G. and Carvalho, L. 2004. Composition and Antioxidant Activities of the Essential Oils of Thymus caespititius, Thymus camphoratus and Thymus mastichina. Food Chem., 86: 183–188.
23. Moldao-Martins, M., Beirao-da-Costa, S., Neves, C., Cavaleiro, C., Salgueiro, L. and Beirao-da-Costa, M. L. 2004. Olive Oil Flavoured by the Essential Oils of Mentha piperita and Thymus mastichina L. Food Qual. Prefer., 15: 447- 452.
24. Naz, S., Sheikh, H., Siddiqi, R. and Asad Sayeed, S. 2004. Oxidative Stability of Olive, Corn and Soybean Oil under Different Conditions. Food Chem., 88: 253–259.
25. Ortega-García, J., Gámez-Meza, N., Noriega-Rodriguez, J. A., Dennis-Quiñonez, O., García-Galindo, H. S., Angulo-Guerrero, J. O. and Medina-Juarez, L. A. 2006. Refining of High Oleic Safflower Oil: Effect on the Sterols and Tocopherols Content. Eur. Food Res. Technol., 223: 775–779.
26. Oyaizu, M. 1986. Studies on Products of the Browning Reaction Prepared from Glucose Amine. Jap. J. Nutr., 44: 307–315.
27. Prieto, P., Pineda, M. and Aguilar, M. 1999. Spectrophotometric Quantitation of Antioxidant Capacity through the Formation of a Phosphomolybdenum Complex: Specific Application to the Determination of Vitamin E. Anal. Biochem., 269: 337–341.
28. Safaei-Ghomi, J., Ebrahimabadi, A., Djafari-Bidgoli, Z. and Batooli, H. 2009. GC/MS Analysis and In vitro Antioxidant Activity of Essential Oil and Methanol Extracts of Thymus caramanicus Jalas and Its Main Constituent Carvacrol. Food Chem., 115: 1524-1528.
29. Sabih Ozer, M., Sarikurkcu, C., Tepe, B. and Can, S. 2010. Essential Oil Composition and Antioxidant Activities of Alkanet (Alkanna tinctoria subsp. tinctoria). Food Sci. Biotechnol., 19(5): 1177-1183.
30. Shimada, K., Fujikawa, K., Yahara, K. and Nakamura, T. 1992. Antioxidative Properties of Xanthan on the Autooxidation of Soybean Oil in Cyclodextrin Emulsion. J. Agric. Food Chem., 40: 945–948.
31. Statsoft. 1998. STATISTICA for Windows (Computer Program Electronic Manual). StatSoft Inc, Tulsa, OK.
32. Sultana, B., Anwar, F. and Przybylski, R. 2007. Antioxidant Potential of Corncob Extracts for Stabilization of Corn Oil Subjected to Microwave Heating. Food Chem., 104: 997–1005.
33. Tepe, B., Sokmen, M., Akpulat, H. A., Daferera, D., Polissiou, M. and Sokmen, A. 2005. Antioxidative Activity of the Essential Oils of Thymus sipyleus subsp sipyleus var. Ripyleus and Thymus sipyleus subsp. sipyleus var. Rosulans. J. Food Eng., 66: 447–454.
34. Undeger, U., Basaran, A., Degen, G. H. and Bassaran, N. 2009. Antioxidant Activities of Major Thyme Ingredients and Lack of (Oxidative) DNA Damage in V79 Chinese Hamster Lung Fibroblast Cells at Low Levels of Carvacrol and Thymol. Food Chem. Toxicol., 47: 2037–2043.
35. Vagi, E., Rapavi, E., Hadolin, M., Peredi, K. V., Balazs, A. and Blazovics, A. 2005. Phenolic and Triterpenoid Antioxidants from Origanum majorana L. Herb and Extracts Obtained with Different Solvents. J. Agric. Food Chem., 53: 17–21.