The occurrence of flavonoids and tannins in the leaves of some African acacia species
Thieme, H.; Khogali, A.
Die Pharmazie 30(11): 736-743
1975
ISSN/ISBN: 0031-7144 PMID: 1219777 Document Number: 93753
Using chromatography of methyl alcohol extracts, each of the 13 taxa studied showed 2 or more flavonoids, with a total of 14 flavonoids found. Most were quercetin glycosides, chiefly as the 3-rutinoside, but also apigenin(I)-6,8-bis-C-glucoside, and luteolin-7-glucoside; sporadically present were myricetin (II) glycosides, II-4'-methyl ether-3-rhamnoside, the 8-C- and 6-C-glucosides of II, and isorhamnetin-3-rutinoside. Total flavonoid content varied between 0.06-2.2%. Leaves of all 13 taxa contained condensed tannins. One species, A. nilotica, showed a particularly high content. Other taxa studied were A. cyanophylla, A. farnesiana, A. horrida, A. longifolia, A. mellifera, A. polyacantha ssp. campylacantha, A. saligna, A. seyal and its var. fistula, A. sieberana, and A. tortilis. Many taxa contained phenolic carboxy acid; some leaves contained salicylic acid. (+)-Catechol, (+)-gallocatechol, (-)-epicatechol-3-gallate and (-)-epigallocatechol-3-gallate were found in a few taxa.