title: Does propolis contain tannins?
abstract: Although polyphenols have been reported as common constituents of propolis, tannins have rarely been mentioned as its constituents. Propolis samples from seven localities in Brazil were analyzed for detection of proanthocyanidins (condensed tannins) and determination of the tannin content. Positive reaction for proanthocyanidins was observed for all samples tested. The contents of tannins varied in the range 0.6-4.1%. A high degree of correlation was noted between total phenols and tannin content. Red and green propolis contained high contents of tannins, while in brown propolis the content was lower. It is suggested that the contents of tannins should be a parameter to be considered in propolis characterization.
authors: University of Santo Amaro, Rua Professor Enéas de Siqueira Neto 340, 04829-900 São Paulo, SP, Brazil.
authors: Marco A S
authors: MA
authors: Mayworm
authors: Department of Botany, Institute of Biosciences, University of São Paulo, Rua do Matão 277, 05508-090 São Paulo, SP, Brazil.
authors: Carolina A
authors: CA
authors: Lima
authors: Department of Botany, Institute of Biosciences, University of São Paulo, Rua do Matão 277, 05508-090 São Paulo, SP, Brazil.
authors: Augusto C B
authors: AC
authors: Tomba
authors: Department of Botany, Institute of Biosciences, University of São Paulo, Rua do Matão 277, 05508-090 São Paulo, SP, Brazil.
authors: Caroline C
authors: CC
authors: Fernandes-Silva
authors: Department of Botany, Institute of Biosciences, University of São Paulo, Rua do Matão 277, 05508-090 São Paulo, SP, Brazil.
authors: Maria L F
authors: ML
authors: Salatino
authors: Department of Botany, Institute of Biosciences, University of São Paulo, Rua do Matão 277, 05508-090 São Paulo, SP, Brazil.
authors: Antonio
authors: 0000-0003-4538-8005
authors: A
authors: Salatino