الفهرس 
Literature ReviewOnly 14 pages are availabe for public view
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Abstract
The objectives of this work are divided into four objects. First target is to synthesis feruloylated structured lipids, through biocatalytic in¬corporation of ferulic acid into vegetable oil lattice in solvent free system (vegetable oil as reaction media) using individual and combinational lipase systems of three commercial lipases; two unspecified lipases, NovoCor ADL and Novozyme435®; and one 1,3-specified lipase, Lipozyme TL 100L. Second object is the extraction of potent antioxidants from olive leaves using aqueous sodium bisulphate solution at 45°C with different pH values and different extraction time followed by the determination of major phenolics such as oleuropein. Third object is the determination of the antiradical capacity of the formed FSLs and enhance its oxidative stabil¬ity via adding the olive leaves extract in ethyl acetate media. Fourth object, present the cheap lipases TLL and ADL as suitable alternative option of expensive N435 for industrial scale application and forming nutritive lipid.
Three types of vegetable oils were selected according to their highest fatty acid content, health benefits, and their uses in food industry. Linseed oil is one of the richest oils of the omega-3 fatty acid, α-linolenic acid (ALA). Also, it possesses bioactive properties useful for health benefits. However, it is very susceptible for oxidation Canola oil is omega-6 rich oil, linoleic acid (LA), useful for health and its wide use in foods. Palm stearin is one of palm oil fraction contains 60 % of palmitic acid; that has massive use in food industry in forms of shortening, margarine, and other forms.
Lipozyme TL 100L and NovoCor ADL considered as two novel use low-cost lipases in feruloylated structured lipids in comparison to wide used Novo-zyme435® lipase.
Ferulic acid possesses high free radical scavenging capacity, excellent UV-absorbing, and antitumor activity. However, ferulic acid has poor solubility in nonpolar media. Therefore, the incorporation will be beneficial for both ferulic acid by increasing its lipophilization and oils by obtaining multifunctional properties combining, for instance, rising their oxidative stability combined with nutritive value for food and cosmetic industries us-es.
Sterols such as β-sitosterol, campesterol, and stigmasterol have high an-tioxidant capacity. Additionally, they have alkoxy group suitable for direct esterifica¬tion with ferulic acid and free fatty acids (palmitic, oleic, linoleic, and α-linolenic acids) that produced from partial enzymatic hydrolysis of oil tri¬acylglycerols. These enzymatic reactions produced steryl ferulates and steryl fatty acid esters.
This thesis was implemented based on preparation, identification and free radical capacity of the enzymatically synthesized feruloylated structured lipids.
This thesis is divided into four chap¬ters as following:
Chapter One: Literature Review
This chapter includes an introduction about structured lipids, lipases, vegetable oils, ferulic acid, sterols, olive leaves, and antioxidant activity. In de¬tails, it includes the lipase types and their regio-/enantio-selectivity, immo¬bilization process, and the previous uses in structured lipids preparation. Additionally, ferulic acid benefits and its esters plus sterol ferulates. The previous reports enzymatic synthesis of FSLs at differ¬ent reaction conditions were stated. The previous reports about the antiox¬idant activity of feruloylated structured lipids and sterol ferulates were presented.
Chapter Two: Materials and Methods
This chapter contains the used chemicals and apparatus in the experi-ments. As well as the experiments setup conditions as following:
• Extraction procedure of potent antioxidants from olive leaves pow¬der (OPL) using 45 ◦C in 0.1 M NaHSO4 aqueous media at different extrac-tion times and pH values; aqueous extraction in H2O as reference.
• Determination of phenols content in olive leave extract (OLE) by HPLC.
• In our laboratory, the oils from linseed and canola seed were extracted by cold-press extrac¬tion technique.
• Determination of fatty acids composition of vegetable oils by GC.
• Lipase immobilization process by physical adsorption method, or¬ganic solvent precipitation.
• Enzymatic transesterification of vegetable oils with ferulic acid.
Enzymatic reactions: the reactants oil:ferulic acid (3:1 mmole ratio, respectively) with absence/presence of 1-2mmole glycerol in solvent free system at 50 - 60°C for 72h us¬ing individual lipases; and combinational lipase systems Lipozyme TL 100L- NovoCor ADL(TLL-ADL) Lipozyme TL 100L- Novozyme435® (TLL-N435) with mass ratio 8:2, respectively.
Detection and identification of Feruloylated oils components, using ESI+-MS total scan and ESI+/MS-MS daughter scan.
• Estimation of the free radical scavenging capacities of raw oils; or feru-loylated oil; or raw oil mixed with OLE; or feruloylated oils mixed with OLE solution in ethyl acetate media (6 %, w/v) using DPPH 20 mM.
Chapter Three: Results and Discussion
In this chapter the results of the experiments and their discussion are stated and illustrated, that divided into two parts as following:
Part One: Biocatalytic Synthesis of Feruloylated Palm Stearin (FPS)
This part focused on the lipase-catalyzed transesterification of ferulic acid with palm stearin in solvent free system using individual lipases, ADL, N435, and TLL; and two combinational lipase systems TLL-ADL and TLL-N435 at 60 °C; support¬ed with scheme, graphs, figures, and tables.
The results and discussion data as following:
• The quantities of phenols in olive leaves extracts.
• Relative percentage of fatty acids of vegetable oils.
• The tentative reaction scheme of transesterification of ferulic acid with palm stearin.
• MS-MS fragmentation analysis of the nineteen FAGs compounds.
• The distribution percentages of all FAGs resulted from all lipase sys¬tems in absence/ and presence of 1mmole glycerol at 60 °C.
• Studying the regioselectivity of all lipase systems according to yielded FAGs %.
• Studying the antioxidant activity of feruloylated palm stearin in comparison to palm stearin.
Part Two: Biocatalytic Synthesis of Feruloylated Linseed and Canola Oils (FLS and FCO)
This part illustrates the enzymatic synthesis of feruloylated linseed and canola oils at 50 and 60°C with all lipase systems and different mmole ratios of glycerol (1 mmole, 2 mmole, and absence of glycerol); that supported with scheme, graphs, figures, and tables.
The results and discussion are presented as following:
• Tentative reaction scheme of enzymatic transesterification of ferulic acid with linseed and canola oils.
• Stating and discussion the distribution % of FAGs components in FLS and FCO.
• Investigating the formation of steryl ferulates and steryl fatty acid esters using ESI+-MS total scan.
• Studying the influence of solvent free system on obtained FAGs %.
• Studying the influence of silica as lipase immobilizer.
• Investigating the free radical scavenging capacity of raw oils and fer-uloylated oils produced from using individual lipase systems.
• Investigating the free radical scavenging capacity of raw oils and fer-uloylated oils produced from using combinational lipase systems.
• Investigating the influence of OLE on the free radical scavenging ca-pacity of the raw oils and feruloylated oils that resulted from us¬ing individual and combinational lipase systems.
Chapter Four: Conclusion
Biocatalytic synthesis of feruloylated structured lipids were successfully achieved in solvent free system using first time use of low-cost NovoCor ADL and Lipozyme TL 100L lipases and their combinational systems in com-parison expensive wide using Novozyme435® lipase as reference at differ-ent reaction temperatures.
NovoCor ADL exhibited great regioselectivity towards incorporating two ferulic acid molecules along with long chain saturated fatty acid (palmitic acid) on glycerol backbone (diferuloyl monopalmitoylglycerol) over long chain unsaturated fatty acids at enzymatic synthesis of FPS in presence of 1mmole free-glycerol.
All individual lipases and their combinational systems with transesterification reaction of LS and CO oils components with ferulic acid have shown regiose¬lectivity towards synthesis monoferuloyl monoacylglycerols; monoferuloyl diacylglycerols over diferuloyl monoacylglycerols; feruloyl-sn-glycerol and diferuloyl-sn-glycerol.
The individual Lipozyme TL 100L and its combinational lipase systems with unspe¬cific lipases, NovoCor ADL and Novozyme435® that showed positive syner¬gistic effect, have successfully synthesized the production feruloylated structured lipids, steryl ferulates, and steryl fatty acid esters.
In general, the free radical scavenging activity of the produced feruloy-lated linseed and canola oils are higher than linseed and canola raw oils.
Olive leaves extract, that has 40 % oleuropein, has added great oxidative stability to feruloylated linseed and canola oils, and their raw oils.
The research over passed the economical obstacle that limits the use of biocatalytic reactions on an industrial semi-large scale by using low-cost li-pases in feruloylated structured lipid formation.