PresentationPresentation

LipidsLipids

Michaela Barošová, Lukáš MalinaMichaela Barošová, Lukáš Malina

Properties of LipidsProperties of LipidsThe Lipids are esters of long chain fatty acids and alcoholsThe Lipids are esters of long chain fatty acids and alcohols

(glycerol).(glycerol).

They are a large and diverse group of naturally occuring organicThey are a large and diverse group of naturally occuring organic

compounds that are compounds that are generally insoluble in water – they are hydrophobic generally insoluble in water – they are hydrophobic soluble in nonpolar solvents such as ether, chloroform, aceton soluble in nonpolar solvents such as ether, chloroform, aceton

etc.etc.

There is a great structural variety among the lipids.There is a great structural variety among the lipids.

diverse - různorodý diverse - různorodý

occuring – vyskytující seoccuring – vyskytující se

Functions of Lipids Functions of Lipids

1.1. store and source of energy for animals and peoplestore and source of energy for animals and people

2.2. solvent (for the lipid soluble vitamins such as A, D, E, K)solvent (for the lipid soluble vitamins such as A, D, E, K)

3.3. structural components of biological membranes structural components of biological membranes

4.4. protective function – they protect some organs in human protective function – they protect some organs in human body (kidneys)body (kidneys)

5.5. both lipids and lipid derivatives serve as vitamins and both lipids and lipid derivatives serve as vitamins and

hormoneshormones

store – rezerva, zásoba protective - ochrannýstore – rezerva, zásoba protective - ochranný

source – zdroj serve - sloužitsource – zdroj serve - sloužit

Classification of LipidsClassification of Lipids

1.1. HomolipidsHomolipids• Fatty acids and their Fatty acids and their

derivativesderivatives• TriacylglycerolsTriacylglycerols• Wax estersWax esters

2.2. HeterolipidsHeterolipids • PhospholipidsPhospholipids• SphingolipidsSphingolipids

wax - voskwax - vosk

Fatty AcidsFatty Acids • their name mostly reflect their name mostly reflect

their sources their sources • natural fatty acids may be natural fatty acids may be

saturated or unsaturatedsaturated or unsaturated • linoleic and linolenic fatty linoleic and linolenic fatty

acids are essential - their acids are essential - their absence in the human diet is absence in the human diet is connected with health connected with health problemsproblems (increased (increased dehydration )dehydration )

reflect – odrážetreflect – odrážetsaturated - nasycenýsaturated - nasycený

SaturatedSaturated UnsaturatedUnsaturatedCommon Common

namenameCommon Common

namename

lauric acid lauric acid palmitoleic palmitoleic acid acid

myristic acid myristic acid oleic acid oleic acid

palmitic acid palmitic acid linoleic acid linoleic acid

stearic acid stearic acid linolenic acid linolenic acid

arachidic acid arachidic acid arachidonic arachidonic acid acid

TriacylglycerolsTriacylglycerols• the triesters of fatty acids with glycerol (1,2,3-the triesters of fatty acids with glycerol (1,2,3-

trihydroxypropane) - CHtrihydroxypropane) - CH22OHCHOHCHOHCHOHCH22OH OH

• are contained both in plants and animalsare contained both in plants and animals• represent one of the major food group of our dietrepresent one of the major food group of our diet• solid at room temperature are classified as fats (occur solid at room temperature are classified as fats (occur

mainly in animals)mainly in animals)• liquid are called oils (mainly in plants, but liquid are called oils (mainly in plants, but

triacylglycerols from fish are also oils)triacylglycerols from fish are also oils)

Triacylglycerols - Triacylglycerols - continuedcontinued

• fats have a predominance of fats have a predominance of saturated fatty acids saturated fatty acids

• oils are composed largely of oils are composed largely of unsaturated acids unsaturated acids

herring – sleďovýherring – sleďový

corn – obilícorn – obilí

peanut – burský oříšekpeanut – burský oříšek

Animal fatsAnimal fats Plant oilsPlant oils

butterbutter coconutcoconut

human fathuman fat corncorn

herring oilherring oil oliveolive

soyabeansoyabean

peanutpeanut

Reactions of TriacylglycerolsReactions of Triacylglycerols

• the acid-catalyzed hydrolysis is used for the acid-catalyzed hydrolysis is used for production of candles:production of candles:

CHCH22–O–COR–O–COR11 CH CH22–OH R–OH R11–COOH–COOH

│ │ │ │

CH–O–CORCH–O–COR22 + 3H + 3H22O O CH–OH CH–OH + + RR22–COOH–COOH

│ │ │ │

CHCH22–O–COR–O–COR33 CH CH22–OH R–OH R33–COOH–COOH

Reactions of Triacylglycerols - Reactions of Triacylglycerols - continuedcontinued

• the base-catalyzed hydrolysis (saponification) is used the base-catalyzed hydrolysis (saponification) is used for production of soapsfor production of soaps

• potassium soaps are soft and were then converted to potassium soaps are soft and were then converted to the harder sodium soaps by washing with salt solutionthe harder sodium soaps by washing with salt solution

CHCH22–O–COR–O–COR11 CH CH22–OH R–OH R11–COONa–COONa

│ │ │ │

CH–O–CORCH–O–COR22 + 3NaOH + 3NaOH CH–OH CH–OH + + RR22–COONa–COONa

│ │ │ │

CHCH22–O–COR–O–COR33 CH CH22–OH R–OH R33–COONa–COONa

Waxes Waxes

• are esters of fatty acids with long chain monohydric alcohols are esters of fatty acids with long chain monohydric alcohols (one hydroxyl group) (one hydroxyl group)

• waxes are widely distributed in nature waxes are widely distributed in nature • the leaves and fruits of many plants have waxy coatings – the leaves and fruits of many plants have waxy coatings –

protect them from dehydration and small predators protect them from dehydration and small predators • examples: spermaceti: CHexamples: spermaceti: CH33(CH(CH22))1414COCO22-(CH-(CH22))1515CHCH33

beeswax: CHbeeswax: CH33(CH(CH22))2424COCO22-(CH-(CH22))2929CHCH33

PhospholipidsPhospholipids • structural components of biomembranesstructural components of biomembranes• hydrophobic domainhydrophobic domain: composed largely of fatty acids: composed largely of fatty acids• hydrophilic domainhydrophilic domain: containes phosphate or other polar groups: containes phosphate or other polar groups

SphingolipidsSphingolipids

• important components of animal and plant membranesimportant components of animal and plant membranes• contain long – chain amino alcohol, in animals contain long – chain amino alcohol, in animals sphingosinesphingosine

compose – skládat secompose – skládat se beeswax – včelí voskbeeswax – včelí vosk

sparmaceti - vorvaňovinasparmaceti - vorvaňovina

ReferencesReferences

• http://education.yahoo.com/reference/encyclopedia/entry/lipidhttp://education.yahoo.com/reference/encyclopedia/entry/lipid• http://encyclopedia.wikipedia.org/wiki/lipidhttp://encyclopedia.wikipedia.org/wiki/lipid• http://biology.clc.uc.edu/couses/bio104/lipids.htmhttp://biology.clc.uc.edu/couses/bio104/lipids.htm• http://www.cem.msu.edu/reusch/VirtualText/lipids.htmhttp://www.cem.msu.edu/reusch/VirtualText/lipids.htm

Thank you for your attentionThank you for your attention