Agriculture Reference
In-Depth Information
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Bioactive ingredients
are those present in a food or supplement that elicit a spe-
cific reaction in the body. For example, antioxidants are bioactive because they
protect the body by controlling lipid oxidation. Another example of bioactivity
is the reduction in plasma cholesterol when isoflavones are added to the diet.
Demonstration of bioactivity of foods or supplements is difficult since many of
the activities delivered by bioactive ingredients have endpoint markers that may
not appear until later. For example, antioxidants that prevent lipid oxidation in the
short term can reduce lifetime risk of cardiovascular disease and some types of
cancer. Typically, potential bioactive ingredients are identified by their chemical
characteristics. A large number of such ingredients have been identified based on
chemical activity as antioxidants.
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The broad spectrum of bioactive ingredients can be broken down by chemical classes.
Figure 13.1 represents the major classes of bioactive ingredients found in functional
foods. For example, the terpenoids include the carotenoids and tocopherols, which
include β-carotene, vitamin A, and α-tocopherol (vitamin E). The phenolics rep-
resent an extremely diverse group of compounds, many of which exert significant
bioactivity. The isoflavones from soy help reduce LDL cholesterol, and the poly-
phenolics, anthocyanins, and phenolic acids all deliver antioxidant activity along
with altering the expression of various genes. For example, polyphenolics have been
shown to reduce the expression of proinflammatory genes in in vitro systems. The
carbohydrates generally deliver fiber, which enhances digestive health and includes
the prebiotics (listed under microbial). The prebiotics are fermented by the probiotic
bacteria, resulting in the production of short-chain fatty acids in the colon. These
short-chain fatty acids are a preferred substrate for the colonic cells, resulting in
Bioactive Ingredients
Te rpenoids
Phenolics
Carbohydrates
Protein or
Amino Acid
Based
Lipid Based
icrobial
Oligosaccharides
Cellulose
Pectin
Glucans
Resistant starch
Te rpenes
Carotenoids
To copherols
To cotrienols
N-3 PUFAs
MUFAs
Lecithin
Sphingolipids
Probiotics
Prebiotics
Flavanols
Flavonones
Isoflavones
Ta nnins
Lignin
Anthocyanins
Polyphenols
Phenolic acids
Amino Acids
Polypeptides
Choline
Allyl-S compounds
fIguRe 13.1
Categories of bioactive ingredients in functional foods. MUFAs, monoun-
saturated fatty acids; N-3 PUFAs, omega-3 polyunsaturated fatty acids.
