Cacao catechin

The cacao plant, Theobroma cacao, is the source of chocolate which is well known and highly prized in international commerce. The cacao pods contain beans which are fermented and pressed to provide a brown liquid which is the raw material for chocolate. The press cake is ground and sold as cocoa and it also provides a brown colorant. The pods, beans, shells, husks and stems have also been suggested as colorants. They contain a very complex mixture of acyl acids, leucoanthocyanins, flavonoid polymers, tannins, and catechin-type polymers.33... 

Gotti, R., Furlanetto, S., Pinzauti, S., and Cavrini, V. (2006). Analysis of catechins in Theobroma cacao beans by cyclodextrin-modifled micellar electrokinetic chromatography.. Chromatogr. A 1112, 345-352. 

Catechin and the proanthocyanidin prodelphinidin B3 are, respectively, the major monomeric and dimeric flavan-3-ols found in barley and malt where prodelphinidin B3 is the main contributor for the radical scavenging activity [Dvorakova et al., 2007], Proanthocyanidins have also been detected in nuts. Hazelnuts (Corylus avellana) and pecans (Carya illinoensis) are particularly rich in proanthocyanidins containing ca. 5 g kg, whereas almonds (Prunus dulcis) and pistachios (Pistachio vera) contain 1.8-2.4 mg kg 1, walnuts (Juglans spp.) ca. 0.67 g kg, roasted peanuts (Arachis hypgaea) 0.16 g kg, and cashews (Anarcardium occidentale) 0.09 g kg 1 [Crozier et al., 2006c]. Dark chocolate derived from the roasted seeds of cocoa (Theobroma cacao) is also a rich source of procyanidins [Gu et al., 2004], Monomeric flavan-3-ols and the proanthocyanidin B2, B5 dimers, and Q trimer are found in fresh cocoa beans (Fig. 1.13). Flavan-3-ols have also been detected in mint... 

The last decade has seen quite remarkable advances in our knowledge of the structure and properties of the proanthocyanidins. Viscosity measurements were made of solutions of procyanidins isolated from Theobroma cacao and Chaenomeles speciosa with number-average degrees of polymerization of 6.1 and 11.8, respectively, in water and 1% sodium hydroxide at 25 °C. Procyanidins are apparently completely crosslinked by formaldehyde up to a chain length of 6 units, but few units are crosslinked in polymeric procyanidins. The second order rate constants observed for the formaldehyde reaction with catechin or epicatechin are approximately six times higher than that observed for the C. speciosa polymer. 

Procyanidins. Catechin (Fluka) and epicatechin (ex. cacao beans) were recrystallized and dried before use. The oligomers epicatechin-(4/ — 8)-epicatechin and [epicatechin-(4/ — 8)]3-epicatechin were obtained from the ethyl acetate sol-... 

Suhagio, A. Sari, P. Morita, N. Simultaneous determination of (+ )-catechin and (— )-epicatechin in cacao and its products by high-performance liquid chromatography with electrochemical detection. Phytochem. Anal. 2001, 12, 104-109. 

The polyphenols in cocoa (Theobroma cacao L.) and cocoa products can be attributed mainly to procyanidins (flavan-3-ols) (37%) [15]. The procyanidins identified range in size from monomers (catechin and epicatechin) to long polymers (with a degree of polymerization higher than 10 or decamers). The concentrations of polyphenols in cocoa products depend on their origin [16] and the cocoa processing... 

In Klein s Handbuch (loc. cit., p. 410), very few identifications of catechins are recorded. Apart from tea and cacao, recent work has shown them to be present in (1) apples (epzcatechin, commonly, catechin in some cider varieties (Bradfield, 1952, Williams, 1952)) (2) pears epi-catechin only in perry varieties in small amounts (Williams, 1952)) (3) peaches (d-catechin (Johnson et al., 1951)). 

Traditionally, there are two main types of cacao, Forastero ( foreign ) in which the beans are purple in section, and CrioUo ( native ) in which they are cream-colored. The purple pigment of the former was shown by Robinson (c/. Knapp, 1937) to be a cyanidin-3-glycoside. The latter were shown by Knapp and Hearne (1939) to contain a leuco-anthocyanin and Forastero beans were found by Hallas (1949) to contain a leuco-anthocyanin in addition to anthocyanin. Both types contain Z-ept catechin (Freudenberg et al., 1932). 

Seeds of Theobroma cacao are worldwide in use for production of cocoa butter and confectionary products. The production of raw cocoa from fresh seeds is based on a complex fermentation process, which leads to the aroma precursors. This process enhances the amount of peptides and free amino acids in the seeds, but it also reduces the amount of phenolic compounds, especially the proantho-cyanidins. These antioxidative compounds are mostly composed of catechin and epicatechin monomers and oligomers up to decamers. The fermentation has to take into account that both factors, production of aroma precursors as well as... 

Kim and Keeny [55] detected between 43,270 and 21,890-mg kg epicatechin in eight different cacao genotypes Tomas-Barberm et al. [56] quantified 25,650-mg kg fat-free dry matter Gotti et al. [57] reported on 15,300-5,700 mg kg It is still unclear whether environmental or genotypic factors dominate the variation. The diastereoisomer (+) catechin is lower in mature cocoa seeds 646 mg kg [56], 450-140 mg kg [57]. 

Raw cocoa seeds contain approximately 6.9—18 % proanthocyanidins of defatted dry weight [61, 62]. Porter et al. [63] described (2R,3S)-(+)-catechin, (2R, 3R)-( )-epicatechin, and the dimers epicatechin-(4(3 8)-catechin (procyanidin Bl, see above) procyanidin B, epicatechin-(4p 6)-epicatechin, and epicatechin-(4p 8)-epicatechin (procyanidin Cl) as the dominating compounds in cacao seeds [63]. Two glycosides 3-0-p-D galactopyranosyl-ent-epicatechin-(2a 7,4 a 8) epicatechin and 3-0-L-arabinopyranosyl ent-epicatechin-(2a 7, 4a 8)-epicatechin were found in addition to epicatechin-(2(i 5,4(3 6)-epicatechin [63,64]. 

Osakabe N, Yasuda A, Natsume M, Takizawa T, Terao J, Kondo K (2002) Catechins and their oligomers linked by C4 - > C8 bonds are major cacao polyphenols and protect low-density lipoprotein from oxidation in vitro. Exp Biol Med 227 51-56... 

Haslam (57) noted earlier that two distinct and very common patterns may be distinguished in the procyanidins (i) those based on epicatechin-4 (T and M) units with also an epicatechin terminal (B) unit, and (ii) those based on epicatechin-4 (T and M) with a contrasting catechin terminal (B) unit. Those included in Type (i) were procyanidins from Malus pumila, Crataegus oxyacantha, Theobroma cacao, Cotoneaster sp., Cydonia oblonga, Prunus cerasus, and Aes-cuius hippocastanum. We have confirmed that this holds true for the procyanidin polymers as well, and others of this type include those from Chaenomeles chinen-sis, Persea americana, and Actinidia chinensis. 

The flavan-3-ols (-l-)-catechin and (—)-epicatechin are among these important dietary constituents owing to their potent antioxidant and anti-inflammatory properties [38]. These compounds usually occur together in plants. Nowadays, separation of catechins most often is achieved with such methods as HPLC or CE. For example, a micellar electrokinetic chromatography method was developed for the separation of (-l-)-catechin and (—)-epicatechin in Theobroma cacao beans. The method also proved suitable for the enantioseparation of ( )-catechin [39]. 

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