Question

Which type of plant secondary metabolite is best known for the antioxidant properties of human foods such as blueberries, tea, and grape juice? a. alkaloids b. cannabinoids c. carotenoids d. phenolics e. terpenoids

Short answer

The correct answer is d. Phenolics.

Step-by-step solution

Review options

Begin by understanding the role of each option in the list. Alkaloids, cannabinoids, carotenoids, phenolics, and terpenoids are all types of secondary metabolites in plants, but each one has distinct properties.

Identify antioxidant compounds

Next, we want to identify which of these secondary metabolites is known for being an antioxidant in human diets. This requires either previous knowledge or research.

Choose known antioxidant

From research and material learned, it's understood that phenolics are a group of chemical compounds found abundantly in nature, they are strong antioxidants because of their ability to scavenge free radicals. Foods such as blueberries, tea, and grape juice are known for their high content of these compounds.

Key concepts

Phenolics

When we talk about the wide array of compounds plants produce, phenolics warrant special attention. These are a group of chemical substances that are characterized by the presence of more than one phenol unit or building block per molecule. Phenolics are produced by plants primarily as a defense mechanism against stressors like infections or injury.

Phenolics have garnered interest owing to their antioxidant activities. They can neutralize free radicals and thereby reduce oxidative stress in plants. This same characteristic is what makes them valuable in human nutrition as well. Consuming foods high in phenolic content, such as blueberries, strawberries, and black tea, helps our body combat oxidative damage that can lead to chronic diseases. In the context of the exercise, phenolics are correctly identified as the antioxidative compounds present in foods like blueberries, tea, and grape juice.

Antioxidants in Human Diet

Antioxidants are a frontline defense system in the human body against oxidative stress that can lead to cell damage and a variety of chronic diseases. They play a pivotal role in maintaining health by protecting cells from the damage caused by excess free radicals.

The term 'antioxidant' covers a range of compounds, including vitamins C and E, flavonoids, and phenolics. These can be found in fruits, vegetables, nuts, and whole grains. Regular consumption of antioxidant-rich foods can boost the body's natural defense system. For instance, lycopene in tomatoes and beta-carotene in carrots are antioxidants that contribute to the vibrant colors of these foods while offering health benefits. In the case given in the exercise, phenolics function as antioxidants and contribute significantly to the health-promoting properties of certain human foods.

Biochemical Compounds of Plants

Plants synthesize a plethora of biochemical compounds, known as secondary metabolites, that are not directly involved in their growth, development, or reproduction. These compounds are incredibly diverse and serve various ecological functions, including defense against herbivores, diseases, and as part of the plant's response to stress.

Secondary metabolites are typically grouped into several categories such as alkaloids, terpenoids, glycosides, and phenolics. Phenolics, for instance, are one class of secondary metabolites that have significant roles in plant defense and also contribute to the color, taste, and aroma of the plant. Understanding these biochemical compounds of plants not only helps in identifying how plants interact with their environment but also opens up possibilities for their use in human medicine and nutrition, as seen in the antioxidant properties of phenolics.