Çözücü Farkının Zeytin Yaprağı Ekstraktı’nın Polifenolik Profiline ve Toplam Fenolik Madde Miktarına Etkisi

Zeytin ağaçları her dem yeşil, pek çok farklı amaç için meyveleri, yaprakları ve gövdesi kullanılabilen en eski bitkilerinden birisidir. Zeytin, özellikle Akdeniz diyetinde ve son zamanlarda da herkesin ilgisini çeken geniş metabolik etkileriyle çok kullanılan bir besin kaynağı haline gelmiştir. Zeytin ve yaprağı polifenolik bileşikler bakımından zengindir. Polifenolik bileşikler arasında da oleuropein en bol bulunan ve en aktif olanıdır. Diğer önemli aktif bileşikler ise hidroksitirozol, tirozol ve verbaskozittir. Oleuropein antioksidan, antidiyabetik ve antimikrobiyal etkilere sahiptir. Bu çalışma; çözücü farkının zeytin yaprağındaki polifenolik bileşiklerin miktarlarına ve toplam fenolik madde miktarına etkisinin araştırılması amacıyla planlanmıştır. Saf su, metanol/su ve metanol solventleri kullanılarak zeytin yaprağı ekstrakte edilmiştir. Elde edilen ekstraktta, içerik tayini kromatografik analiz kullanılarak araştırılmıştır. Ayrıca toplam fenolik madde miktarı Folin-Ciocalteu metodu ile spektrofotometrik yöntem kullanılarak tespit edilmiştir. Kromatografik analizler sonucunda metanolik solventlerin oleuropeini zeytin yaprağından daha etkin bir şekilde ekstrakte ettiği bulunmuştur. Solvent olarak su kullanıldığında ise hidroksitirozol, tirozol ve verbaskozitin daha iyi ekstrakte edildiği tespit edilmiştir. Ekstrakte edilen toplam fenolik madde miktarı bakımından solventler karşılaştırıldığında sırasıyla metanol, metanol/su ve suda en yüksek miktarlar bulunmuştur. Sonuç olarak, yüksek hidrofilik karakterlerinden dolayı polifenolik bileşiklerin, polaritesi fazla olan metanolik solventlerde daha verimli ekstrakte edilebileceği belirlenmiştir.

Anahtar Kelimeler:

Ekstraksiyon, HPLC, Oleuropein, Zeytin, Toplam fenolik madde

Effect of Solvent Variation on Polyphenolic Profile and Total Phenolic Content of Olive Leaf Extract

Olive tree is one of the oldest plants, evergreen and of which fruits, leaves and trunk can be used for many different purposes. Olive has become a nutritional source widely used for especially in the Mediterranean diet and due to its extensive metabolic effects attracting everyone's attention recently. Olive and olive leaves are rich in polyphenolic compounds. Oleuropein is the most available and most active polyphenolic compound. Hydroxytyrosol, tyrosol and verbascoside are other important active compounds. Oleuropein has antioxidant, antidiabetic and antimicrobial effects. This study was investigated the effects of solvent variation on the amount of polyphenolic compounds and total phenolic content in olive leaves. The olive leaves were extracted using water, methanol/water and methanol solvents. The content of olive leaves extract was investigated by chromatographic analysis. Also total phenolic content was determined using Folin-Ciocalteu method by spectrophotometric method. The chromatographic analysis showed that methanolic solvents more effectively extracted oleuropein from olive leaf. However, when water was used as a solvent, hydroxytyrosol, tyrosol and verbascoside were extracted better from olive leaf. When solvents were compared in respect to their total phenolic content; the order from highest to lower was respectively methanol, methanol/water, and water. Consequently, due to their high hydrophilic character; polyphenolic compounds can more efficiently be extracted in methanolic solvents with high polarity.

Keywords:

Extraction, HPLC, Oleuropein, Olive, Total phenolic content,

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Amiot MJ, Fleuriet A, Macheix JJ (1989). Accumulation of oleuropein derivatives during olive maturation. Phytochemistry 28: 67-70.
Bouallagui Z, Han J, Isoda H, Sayad S (2011). Hydroxytyrosol rich extract from olive leaves modulates cell cycle progression in MCF-7 human breast cancer cells. Food Chem. Toxicol. 49: 179-184.
Bouaziz M, Sayadi S (2005). Isolation and evaluation of antioxidants from leaves of a Tunisian cultivar olive tree. Eur. J. Lipid Sci. Technol. 107: 497-504.
Bourquelot E, Vintilesco J (1908). Sur l’oleuropeine, nouveau principle de nature glucosidique retire de l’olivier (Olea europaea L.). Comptes Rendus, 147: 533-535.
Briante R, Patumi M, Limongelli S, Febbraio F, Vaccaro C, Di Salle A, La Cara F, Nucci R (2002). Changes in phenolic and enzymatic activities content during fruit ripening in two Italian cultivars of Olea europaea L. Plant Sci. 162: 791-798.
Cruess WV, Alsberg CL (1934). The bitter glucoside of the olive. J. Am. Chem. Soc. 56: 2115-2117.
Curren MS, King JW (2001). Ethanol-modified subcritical water extraction combined with solid-phase microextraction for determining atrazine in beef kidney. J. Agric. Food Chem. 49: 2175-2180.
Dai J, Mumper RJ (2010). Plant Phenolics: Extraction, Analysis and Their Antioxidant and Anticancer Properties. Molecules 15: 7313-7352.
Di Benedetto R, Varì R, Scazzocchio B, Filesi C, Santangelo C, Giovannini C, Matarrese P, D’Archivio M, Masella R (2007). Tyrosol, the major extra virgin olive oil compound, restored intracellular antioxidant defences in spite of its weak antioxidative effectiveness. Nutr. Meta. Car. 17: 535-545.
Granados-Principal S, Quiles JL, Ramirez-Tortosa CL, Sanchez-Rovira P, Ramirez-Tortosa MC (2010). Hydroxytyrosol: from laboratory investigations to future clinical trials. Nutr. Rev. 68: 191-206.
Ibanez E, Kubatova A, Senorans FJ, Cavero S, Reglero G, Hawthorne SB (2003). Subcritical water extractio o antioxidant compounds from rosemary plants. J. Agric. Food Chem. 51: 375-382.
Jemai H, Bouaziz M, Fki I, El Feki A, Sayadi S (2008). Hypolipidemic and antioxidant activities of oleuropein and its hydrolysis derivative-rich extracts from Chemlali olive leaves. Chem-Biol Interact. 176: 88-98.
Jemai H, El Feki A, Sayadi S (2009). Antidiabetic and antioxidant effects of hydroxytyrosol and oleuropein from olive leaves in alloxan-diabetic rats. J. Agric. Food Chem. 57 (19): 8798-8804. Kubatova A, Miller DJ, Hawthorne SB (2001). Comparison of subcritical water and organic solvents for extracting kava lactones from kava root. J. Chromatogr. A 9236: 187-194.
Lee-Hung S, Zhang L, Huang PL, Chang YT, Huang PL (2003). Anti-HIV activity of olive leaf extract (OLE) and modulation of host cell gene expression by HIV-1infection and OLE treatment. Biochem. Bioph. Res. Co. 307: 1029-1037.
Omar SH, (2010). Oleuropein in Olive and its Pharmacological Effects. Sci. Pharm. 78: 133-154.
Pereira AP, Ferreira I, Marcelino F, Valentão P, Andrade PB, Seabra R, Estevinho L, Bento A, Pereir JA (2007). Phenolic Compounds and Antimicrobial Activity of Olive (Olea europaea L. Cv. Cobrançosa) Leaves. Molecules 12: 1153-1162.
Ryan D, Antolovich M, Prenzler P, Robards K, Lavee S (2002). Biotransformations of phenolic compounds in Olea europaea L. Sci. Hortic. 92: 147-176.
Servili M, Selvaggini R, Esposto S, Taticchi A, Montedoro GF, Morozzi G (2004). Health and sensory properties of virgin olive oil hydrophilic phenols: agronomic and technological aspects of production that affect their occurrence in the oil. J. Chromatogr. A 1054: 113-127.
Salta FN, Mylona A, Chiou A, Boskou G, Andrikopoulos NK (2007). Oxidative Stability of Edible Vegetable Oils Enriched in Polyphenols with Olive Leaf Extract. Food Sci. Tec. Int. 13(6): 413-421.
Silva S, Gomes L, Leitão F, Coelho AV, Vilas Boas L (2006). Phenolic Compounds and Antioxidant Activity of Olea europaea L. Fruits and Leaves. Food Sci Technol Int 12(5): 385-396.
Slinkard K, Singleton VL (1977). Total Phenol Analysis: Automation and Comparison with Manual Methods. Am. J. Enol. Viticult. 28: 49-55.
Soler-Rivas C, Espin, JC, Wichers HJ (2000). Oleuropein and related compounds. J. Agric. Food Chem. 80: 1013-1023.
Somova LI, Shode FO, Ramnanan P, Nadar A (2003). Antihypertensive, antiatherosclerotic and antioxidant activity of triterpenoids isolated from Olea europaea, subspecies africana leaves. J. Ethnopharmacol 84: 299-305.
Taamalli A, Arráez-Román D, Barrajón-Catalán E, Ruiz-Torres V, Pérez-Sánchez A, Herrero M, Ibañez E, Micol V, Zarrouk M, Segura-Carretero A, et al. (2011). Use of advanced techniques for the extraction of phenolic compounds from Tunisian olive leaves: Phenolic composition and cytotoxicity against human breast cancer cells. Food Chem. Toxicol. 50: 1817-1825.