Question

Antioxidant which is obtained from a desert plant and shows synergistic action with citric acid is:

• A. Maleic acid
• B. BHA
• C. Tocopherols
• D. Nordihydroguaiaretic acid (NDGA)

Answer 1

The Correct Option is D

The correct option is (D): Nordihydroguaiaretic acid (NDGA).

Answer 2

The question asks for a fat-soluble antioxidant that comes from a desert plant and works together with citric acid to protect fats and oils from rancidity. Let's look at each option on its own merits.

1. Maleic acid: Maleic acid is a small dicarboxylic acid used mainly as a chemical intermediate and acidulant. It does not act as a primary antioxidant in fats, and it has no link to a desert plant source.
2. BHA: Butylated hydroxyanisole is a widely used synthetic phenolic antioxidant made in the laboratory from petrochemical starting material. It works well in fats, but it is not obtained from a plant at all, desert or otherwise.
3. Tocopherols: Tocopherols (vitamin E) are natural fat-soluble antioxidants, but they come from vegetable oils such as wheat germ, corn, and soybean oil, not from a desert plant.
4. Nordihydroguaiaretic acid (NDGA): NDGA is extracted from the leaves and twigs of Larrea divaricata (creosote bush), a shrub native to the arid deserts of the southwestern United States and Mexico. It is a strong fat-soluble antioxidant, and because it also chelates trace metal ions, it shows a synergistic boost in activity when combined with citric acid, which is itself a metal chelator.

Only NDGA matches both parts of the question: a desert-plant origin and true synergism with citric acid through metal chelation.

So the correct answer is Nordihydroguaiaretic acid (NDGA).