Certain omega-3 fatty acids can be found only in animal sources, such as fatty fish. Two of these are eicosapentaenoic acid (EPA) [20:5] and docosahexaenoic acid (DHA) [22:6], both of which are ω-3 fatty acids. DHA has been shown to be important in healthy brain development, so it has recently been added to infant formulas. Breast milk is rich in DHA as long as the mother maintains a healthy diet that includes fish. Draw skeletal structures of the fatty acids EPA and DHA.

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Welcome back everyone. Meat acid 22 3 is an omega nine fatty acid in the human body. A high amount of meat acid in the body indicates a deficiency of essential fatty acids. On the other hand, stoic acid 18 to 4 is an omega three fatty acid found in hemp and black. Current draw the skeletal structures of meat acid and stoic acid. So let's begin with the first one which is meat acid. Let's understand the notation, it says 20 to 3, which means that we have 20 carbons and three double bonds in the structure, right? Considering only the double bonds from the carbon carbon, double bonds, not including Carbel. And our Omega nine essentially means that the first double bond starts at carbon. Number nine, not according to the OPEC rules, but relative to the methyl carbon. So what we want to do is simply begin by adding the first carbon from the methyl group, right? Let's add it. Car number one, number two, number three, number four, number five, number 678 and mine. And this is where the first double bond starts because we have omega nine, right? So 123456789. We want to draw the double bond in the cis configuration, meaning the alkyl groups must be on the same side relative to the double bond. And now we can draw carbon number 10. Now, we have two more double bonds to assign and we have to recall that they appear in intervals of three, so 123. And then once again, we get a double bond, 12 3rd carbon. And once again, the next carbon is going to have another double bond. According to the notation, we must have three double bonds, 123, double bonds. Now, if we need 20 carbons, we can count how many we already have. 123456789, 1011, 1213, 1415, 1617. So we need three more 18, 19 and 20. And that carbon essentially is going to form carboxyl because we must have an acid, right? So now let's look at the structure. We have 20 carbons, we double bonds. The first double bond starts at carbon number nine, relative to the methyl, not relative to carboxyl. And of course, we must have carboxyl present because this is an acid. So we have our first structure. Now, let's consider a steroid donic acid. According to the context, we have 18 to 4 omega three. So the first double bond is going to start at carbon number three, relative to the methyl group. So 12 and three. And once again, we want to draw this configuration and we must have four double bonds. Let's recall the interval of three. So essentially, we want to draw CH two followed by another double bond, another C two, another double bond in this configuration. And we need the fourth one. Well done. Now, we have four double bonds, omega three and a total of 18 carbons. So 123456789, 1011, 1213, 14. So four more one to we and for, and of course, this is an acid. So at the end of the chain, we're just adding carboxy and that's it. We have drawn the two required structures. Thank you for watching.

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Key Concepts

Omega-3 Fatty Acids

Skeletal Structures of Fatty Acids

Role of DHA in Brain Development