Phytochemistry

Question 1

Phytochemistry

Answer 1

Phytochemistry is the study of chemicals derived from plants and includes primary metabolites and secondary metabolites

Question 2

Primary metabolites

Answer 2

Primary metabolites — compounds in the plant that are needed for the plant to grow and function. Includes:

– Starch for energy storage.

– Chlorophyll for carbohydrate production.

– Cellulose to withstand cellular pressure.

– Lignin for structural support.

Primary metabolites are important in nutritional medicine e.g., starch provides energy, cellulose and lignin provide digestive fibre.

Question 3

Secondary metabolites

Answer 3

Secondary metabolites assist the plants’ survival within its environment e.g., defence against plant pathogens, protection from decomposition, compounds that attract pollinators.

• They are pharmacologically active in humans and central to the effects of herbal medicines e.g., coffee beans contain the alkaloid caffeine, a natural pesticide that protects the fruits against insect attacks. In human physiology caffeine acts as a CNS stimulant.
• Tannins in plants e.g., green tea protect the woody parts of the plant from decomposition and insects. Tannins astringe mucous membranes and reduce watery secretions (runny nose, diarrhoea).

Question 4

Alkaloids

Answer 4

Strong stimulant effects on the nervous system

Berberis vulgaris (berberine)

Question 5

Anthraquinones

Answer 5

Cause powerful evacuation

Senna

Question 6

Flavonoids

Answer 6

Anti-oxidant and anti-viral

Hawthorn berry

Question 7

Saponins

Answer 7

Adaptogenic and steroidlike effects

Liquorice

Question 8

Tannins

Answer 8

Astringent (bind to proteins) and dry out wounds

Yarrow