LIPID METABOLISM 4/19/ Metabolisme Lipida Hendra Wijaya Esa Unggul University

INDEKS CHARACTERISTICS OF LIPID DIGESTION AND ABSORPTION OF LIPID TRANSPORT OF LIPID BETA-OXIDATION OF LIPID SYNTHESIS OF LIPID

CHARACTERISTIC OF LIPID 4/19/ Metabolisme Lipida Hendra Wijaya Esa Unggul University

TYPES OF LIPIDS IN THE BODY Fatty Acids TriglyceridesSterolsPhospholipids TYPES OF LIPIDS IN THE BODY Fatty Acids TriglyceridesSterolsPhospholipids ROLE OF LIPIDS IN THE BODY Energy (9 kcal/gram) Energy to make muscles contract, including heart - supplied mostly from fat Insulate body against temperature extremes Protect the body’s vital organs from shock Form the major material of cell membranes Nerve transmission Contain or transport fat-soluble vitamins ROLE OF LIPIDS IN THE BODY Energy (9 kcal/gram) Energy to make muscles contract, including heart - supplied mostly from fat Insulate body against temperature extremes Protect the body’s vital organs from shock Form the major material of cell membranes Nerve transmission Contain or transport fat-soluble vitamins ROLE OF LIPIDS IN FOOD Enhance Flavor SatietyTexture Solid to Liquid Enhance Tenderness Carry fat-soluble vitamins Can be visible or hidden ROLE OF LIPIDS IN FOOD Enhance Flavor SatietyTexture Solid to Liquid Enhance Tenderness Carry fat-soluble vitamins Can be visible or hidden 4/19/ Metabolisme Lipida

CHARACTERISTICS OF FATTY ACIDS Rarely exist alone - are part of triglycerides or phospholipids Structure : Chain Length - Short (2-4 C), Medium (6-10 C), Long (>12 C) Saturation = Presence or Absence of Double Bonds Rarely exist alone - are part of triglycerides or phospholipids Structure : Chain Length - Short (2-4 C), Medium (6-10 C), Long (>12 C) Saturation = Presence or Absence of Double Bonds Saturated Fatty Acids Unsaturated Fatty Acids 4/19/ Metabolisme Lipida

CHARACTERISTICS OF FATTY ACIDS

Trans- and Cis-Fatty Acids Trans- result when PUFA’s are hydrogenated. In hydrogenation the double bond is broken and is saturated with H atoms Has same health effects as saturated fatty acids Cis- how most fats occur in nature. The hydrogens next to the double bonds are on the same side of the carbon chain. MAY NOT BE AS CHOLESTEROL RAISING AS TRANS-FATTY ACIDS Trans- result when PUFA’s are hydrogenated. In hydrogenation the double bond is broken and is saturated with H atoms Has same health effects as saturated fatty acids Cis- how most fats occur in nature. The hydrogens next to the double bonds are on the same side of the carbon chain. MAY NOT BE AS CHOLESTEROL RAISING AS TRANS-FATTY ACIDS 3/22/2007 Metabolisme Lipida 89 4/19/ Metabolisme Lipida

4/19/ TRANS-FATS Dietary trans fats raise the level of low-density lipoproteins (LDL or "bad cholesterol"). Trans fats also reduce high-density lipoproteins (HDL or "good cholesterol"), and raise levels of triglycerides in the blood.  increasing the risk of coronary heart disease. Metabolisme Lipida

4/19/ THE TOP 10 TRANS-FAT FOODS Data: U.S. Food & Drug Administration (2011) Trans fatty acids: not only increase LDL level, but also decrease HDL level salad dressingfried potatodoughnutcakemayonnaisemargarinecrispy fried potatochocolate barcreamy biscuitmargarine spread Metabolisme Lipida

Essential Fatty Acids Human body cannot make a C=C bond before the 10th carbon in a fatty acid. Thus, essential fatty acids must come from food sources Essential Fatty Acids Human body cannot make a C=C bond before the 10th carbon in a fatty acid. Thus, essential fatty acids must come from food sources 18:2; 9,12  asam linoleat; 18:3; 9, 12, 15  asam linolenat 4/19/ Metabolisme Lipida

Asam linoleat dan linolenat tergolong sebagai asam lemak esensial (tidak dapat disintesis oleh tubuh), sehingga harus selalu disuplai dari makanan. Gejala klinis yang menandai defisiensi asam lemak esensial antara lain, kulit kasar dan kering, terhambatnya pertumbuhan pada bayi dan anak-anak, meningkatnya kemudahan terserang infeksi dan luka yang tidak cepat sembuh (Jeppesen et al, 1998). Tahap Kehidupan Umur (tahun)Sumber AL omega-6 Laki-laki (g/hari) Wanita (g/hari) Bayi0-6 blASI4,4 Bayi7-12 blASI4,6 Anak-anak1-3 thLA7,0 Anak-anak4-8 thLA10,0 Anak-anak9-13 thLA12,010,0 Remaja14-18 thLA16,011,0 Dewasa19-50 thLA17,012,0 Dewasa> 51LA14,011,0 Ibu hamilSemua umurLA-13,0 Ibu menyusuiSemua umurLA-13,0 Tahap Kehidupan Umur (tahun)Sumber AL omega-3 Laki-laki (g/hari) Wanita (g/hari) Bayi0-6 blALA, EPA, DHA0,5 Bayi7-12 blALA, EPA, DHA0,5 Anak-anak1-3 thALA0,7 Anak-anak4-8 thALA0,9 Anak-anak9-13 thALA1,21,0 Remaja14-18 thALA1,61,1 Dewasa> 19 thALA1,61,1 Ibu hamilSemua umurALA-1,4 Ibu menyusuiSemua umurALA-1,3 Kecukupan konsumsi asam lemak omega-6 dan omega-3 yang dianjurkan LA = asam linoleat ALA = asam alfa-linolenat, EPA = asam eikosapentaenoat; DHA = asam dokosaheksaenoat. Sumber: Institute of Medicine (2002). 4/19/ Metabolisme Lipida

TRIGLYCERIDESTRIGLYCERIDES Glycerol Molecule + 3 FA Molecules Glycerol Molecule + 3 FA Molecules Storage form of fatty acids in the body Storage form of fatty acids in the body Most common fat in foods - 95% Most common fat in foods - 95% Glycerol Molecule + 3 FA Molecules Glycerol Molecule + 3 FA Molecules Storage form of fatty acids in the body Storage form of fatty acids in the body Most common fat in foods - 95% Most common fat in foods - 95% 4/19/ Metabolisme Lipida

PHOSPHOLIPIDSPHOSPHOLIPIDS These compounds are similar to triglycerides, but have choline (or another compound) and a phosphorus- containing acid in place of one of the fatty acids These compounds are similar to triglycerides, but have choline (or another compound) and a phosphorus- containing acid in place of one of the fatty acids Have a hydrophobic and hydrophilic end Have a hydrophobic and hydrophilic end They are important constituents of cell membranes They are important constituents of cell membranes Help form micelles which are emulsifiers Help form micelles which are emulsifiers Lecithin is a well known phospholipid Lecithin is a well known phospholipid These compounds are not essential These compounds are not essential These compounds are similar to triglycerides, but have choline (or another compound) and a phosphorus- containing acid in place of one of the fatty acids These compounds are similar to triglycerides, but have choline (or another compound) and a phosphorus- containing acid in place of one of the fatty acids Have a hydrophobic and hydrophilic end Have a hydrophobic and hydrophilic end They are important constituents of cell membranes They are important constituents of cell membranes Help form micelles which are emulsifiers Help form micelles which are emulsifiers Lecithin is a well known phospholipid Lecithin is a well known phospholipid These compounds are not essential These compounds are not essential 4/19/ Metabolisme Lipida

STEROID Most cholesterol is made by the body Most cholesterol is made by the body Very little cholesterol in foods except: Brains, Liver, Shellfish, Eggs Very little cholesterol in foods except: Brains, Liver, Shellfish, Eggs Most cholesterol is made by the body Most cholesterol is made by the body Very little cholesterol in foods except: Brains, Liver, Shellfish, Eggs Very little cholesterol in foods except: Brains, Liver, Shellfish, Eggs

Other lipid: Eicosonoid