PHBioChem (Lecture) | Module 2: ENERGY-STORAGE LIPIDS (Part 2)

Triacylglycerols

This is the formal chemical name, while "triglycerides" is the more common term, especially in clinical settings. (TAG)

Triacylglycerols

Function as energy-storage (more efficient than glycogen in long term)

Triacylglycerols

Located at special cells (adipocytes, mammary glands, abdomen)

Triacylglycerols

More efficient and most abundant

Triacylglycerols

Formation through Esterification

Ester, and Water

COOH + ROH =

Glycerol

a three-carbon alcohol with three hydroxyl groups

25

The normal room temperature is at what degree Celsius?

Fats

FATS VS. OILS: Solid or semi-solid at room temperature, saturated FA

Oils

FATS VS. OILS: Liquid at room temperature, unsaturated FA, lower melting point

Fats, and Oils

naturally occurring complex mixtures of triacylglycerol molecules containing different kinds of triacylglycerol molecules

Fats

FATS VS. OILS: mostly SFA, some UFA

Fats

FATS VS. OILS: “linearity” – higher MP

Fats

FATS VS. OILS: generally obtained from animals “animal fat”

Fats

FATS VS. OILS: pure: colorless, odorless and tasteless

Oils

FATS VS. OILS: MUFA / PUFA

Oils

FATS VS. OILS: “bends” – lower MP

Oils

FATS VS. OILS: usually plant sources others – fish oils

Oils

FATS VS. OILS: color, odor and taste due to small amounts of natural occurrence of substances present in plants

Canola Oil

Considered as the healthiest oil because it has 6% saturated FA, 58% MUFA, 36% PUFA

Coconut Oil

Considered as the unhealthiest oil because it has 92% saturated FA, 6% MUFA, 2% PUFA

Saturated Fats

DIETARY CONSIDERATIONS: animal products like red meat, poultry, and full-fat dairy, as well as some tropical oils like coconut oil and palm oil.

Saturated Fats

DIETARY CONSIDERATIONS: limiting ___________ intake to less than 10% of your daily calories.

Saturated Fats

DIETARY CONSIDERATIONS: can increase heart disease (atherosclerosis)

Monounsaturated Fats

DIETARY CONSIDERATIONS: can decrease both heart disease and breast cancer risk help reduce the stickiness of blood platelets.

Monounsaturated Fats

DIETARY CONSIDERATIONS: olive, avocado, and canola oils, most tree nuts and peanuts

Monounsaturated Fats

DIETARY CONSIDERATIONS: A diet containing 15% ______________ is generally considered to be within the healthy range

30%

Lipid intake of humans

Polyunsaturated Fats

DIETARY CONSIDERATIONS: no more than 10% of your daily calories should come from ________________

Polyunsaturated Fats

DIETARY CONSIDERATIONS: can reduce heart disease risk but promote the risk of certain types of cancers.

Enuit People

They exhibit a low incidence of heart disease despite having a diet very high in fat

Omega-3 Fatty Acids

Common food of Enuit People is fish, the omega fatty acid is?

American People

high-fat diet and a high incidence of heart disease

Omega-6 Fatty Acids

Common food of American People is burger, the omega fatty acid is?

America

The fish is leaner (cold) than Greenland

Essential Fatty Acids

Neededin the human body. Obtained from dietary sources. The body cannot produce these.

Linoleic Acid, and Linolenic Acid

Two Essential FAs

Linoleic Acid

(18:2) Omega-6

Linolenic Acid

(18:3) Omega-3

Linoleic Acid, and Linolenic Acid

Needed for proper membrane structure

Linoleic Acid, and Linolenic Acid

Serve as starting materials for the production of several nutritionally important longer

Linoleic Acid, and Linolenic Acid

the skin reddens and becomes irritated, infections and dehydration, and the liver may develop abnormalities if there is lack of these

Arachidonic Acid

OMEGA-6 FATTY ACIDS: Linoleic Acid (18:2) → ___________ (20:4)

Arachidonic Acid

OMEGA-6 FATTY ACIDS: Needed for eicosanoids

Eicosapentaenoic Acid, and Docosahexanoic Acid

OMEGA-3 FATTY ACIDS: Linolenic Acid (18:3) → ______________ (20:5) → _______________ (22:6)

Eicosapentaenoic Acid, and Docosahexanoic Acid

OMEGA-3 FATTY ACIDS: for brain development and eye retina

Omega-3 Fatty Acids

WHAT OMEGA FATTY ACID: Linolenic Acid (ALA) - 18:3

Omega-3 Fatty Acids

WHAT OMEGA FATTY ACID: Eicosapentaenoic Acid (EPA) - 20:5

Omega-3 Fatty Acids

WHAT OMEGA FATTY ACID: Docosahexaenoic Acid (DHA) - 22:6

Omega-3 Fatty Acids, and Omega-6 Fatty Acids

WHAT OMEGA FATTY ACID: ESSENTIAL FATTY ACID (PUFA)

Omega-6 Fatty Acids

WHAT OMEGA FATTY ACID: Linoleic Acid - 18:2

Omega-6 Fatty Acids

WHAT OMEGA FATTY ACID: Arachidonic acid - 20:4

Omega-9 Fatty Acids

WHAT OMEGA FATTY ACID: Oleic Acid –18:1

Omega-9 Fatty Acids

WHAT OMEGA FATTY ACID: NONESSENTIAL FATTY ACID (MUFA)

Palmitoleic Acid

16:1 (Omega-7 Amino Acid)

Hydrolysis, Saponification, Hydrogenation, and Oxidation

Chemical Reaction of Triacylglycerols

Hydrolysis

Reverse of the esterification reaction by which the triacylglycerol is formed.

Glycerol, and Fatty Acid

HYDROLYSIS: In Acidic conditions, products are?

Glycerol, and Fatty Acid Salts

HYDROLYSIS: In Basic conditions, products are? (also Saponification)

Complete Hydrolysis

HYDROLYSIS: Three fatty acids are removed

Partial Hydrolysis

HYDROLYSIS: One or more fatty acid residues remains attached to the glycerol.

Saponification

Reaction is carried out in an alkaline solution.

Glycerol, and Three Fatty Acid Molecules

SAPONIFICATION STEPS:

1. Hydrolysis of the ester linkages to produce?

2. Reaction between the fatty acid molecules and the base (NaOH) in the alkaline solution.

Three Fatty Acid Salts, and Three Water Molecules

SAPONIFICATION STEPS:

1. Hydrolysis of the ester linkages to produce glycerol and three fatty acid molecules.

2. Reaction between the fatty acid molecules and the base (NaOH) in the alkaline solution, products are?

Animal Fat

Saponification of _________ was the precursor to soap making

Lard with Lye

In the past, soap was made by heating?

Sodium carbonate

Today, most soap is hydrolyzed under high pressure and temperature, using ____________ as the base.

Carboxylate Ions

Soap's cleansing action is influenced by the structure of ___________ in the fatty acid salts.

Micelle Formation

This is a key process in soap production

Hydrogenation

Involves the hydrogen addition across C C multiple bonds, which increase the degree of saturation as some double bonds are covered with single bonds which also increases the MP of the substance

Partial Hydrogenation

some of the double bonds are converted to single bonds.

Hydrogenation

convert cis double bonds in fatty acids into trans double bonds.

Saturated Fats

Dietary recommendations emphasize reducing ___________ intake due to elevated blood cholesterol.

Blood Cholesterol

Partially hydrogenated vegetable oils may increase ____________ levels.

Trans

Studies show _____ double bonds affect blood cholesterol levels similarly to saturated fatty acids.

15%-20%

Trans fatty acids (TFAs) make up _% - _% of dietary TFA intake.

Trans Fatty Acids

Reduces HDL levels and increases LDL levels

Trans Fatty Acids

Promotes an excess of cholesterol. Promotes visceral fat deposits. Increases the risk of cardiovascular diseases.

Trans

Since 2006, ____ fat content in food products must be included in the nutrition facts panel

Less Than 0.5 Gram

Trans fat levels ___________ per serving can be labeled as 0 grams per serving.

Oxidation

C-C double bonds in the FA residues of TAG are oxidized with molecular oxygen resulting in aldehydes and carboxylic acid products.

Aldehydes, and Carboxylic Acid

C-C double bonds in the FA residues of TAG are oxidized with molecular oxygen resulting in?

Rancidity

unpleasant odors and can lead to _______ in fats and oils.

Oxidation

foods with antioxidants (vitamin C and E) and oxidation inhibitors (BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene) are often used as preservative to prevent?

Linolenic Acid

This is the primary member of Omega-3 family

Linoleic Acid

This is the primary member of Omega-6 family