Thesis-Final 03 June 2011 pdf - Jacobs University

Background Chapter 2
Hydroxycinnamic acids such as caffeic, ferulic, sinapic and p-coumaric acids are
present in a large variety of fruits and vegetables including blueberries, grapes, apples,
cereal brans, broccoli, spinach and lettuce (Figure 12).
Sinapic acid trans-Cinnamic acid p- Coumaric acid Ferulic acid Caffeic acid
Figure 12: Structure of five most common hydroxycinnamates. The hydroxy
cinnamates all have a single phenolic ring structure and differ in their side chain.
The important source of cinnamates reviewed by Clifford 63 and divided into two
categories i) a particular cinnamate (independent of the conjugate type and extent of
hydrolysis in the gastrointestinal tract) and ii) a particular conjugate (Table 3).
Class of compound
(i) Cinnamates
Caffeic acid
p-Coumaric acid
Ferulic acid
Sinapic acid
(ii) Conjugates
Caffeoylquinic acids
p-Coumaroylquinic acids
Feruloylquinic acids
Tartaric conjugates
Malic conjugates
Rosmarinic acid
Cell wall conjugates
Main dietary source
Coffee beverage, blueberries, apples, ciders
Spinach, sugar beet, cereal brans
Coffee, citrus juices, sugar beet fibre, cereal brans
Broccoli, kale, other leafy brassicas, citrus juices
Coffee beverage, blueberries, apples, ciders
Sweet cherries
Coffee
Spinach, lettuce, grapes, wines
Lettuce, spinach, possibly legumes
Culinary herbs, mixed herbs, possibly stuffings
Spinach, sugar beet fibre, cereal brans.
Table 3 : Important source(s) of (i) individual cinnamates (regardless of conjugate
type) and (ii) each major class of conjugate.
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