title: Antioxidant potential, tannin and polyphenol contents of seed and pericarp of three Coffea species.
abstract: OBJECTIVE
  To investigate the antioxidant activity, total phenolic and total tannin content of the pericarp and the seed of Coffea benghalensis (C. benghalensis) and Coffea liberica compared to Coffea arabica (C. arabica).
  
  
  METHODS
  The antioxidant potential, total tannin and polyphenol contents of the immature and mature seed and pericarp of C. benghalensis and Coffea liberica were quantified and compared to C. arabica. Enhanced chemiluminescence (ECL), 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity, Folin-Ciocalteau method and total tannin content assays were used.
  
  
  RESULTS
  Trolox equivalent (TE/g plant material) values obtained by ECL and DPPH methods showed loose correlation (r(2) = 0.587) while those measured by oxygen radical absorbance capacity assay were higher without correlation in each plant. A closer correlation was detected between the ECL method and the percentage antioxidant activity of the DPPH technique (r(2) = 0.610 7) in each species, however the immature pericarp of C. benghalensis showed much higher DPPH scavenging potential than was seen in the ECL assay. The immature pericarp of C. benghalensis expressed the highest tannin and polyphenol content, and a high polyphenol level was also detected in the immature seed of C. arabica. The immature pericarp of Bengal and Liberian coffees showed the largest amount of phenolic contents.
  
  
  CONCLUSIONS
  The obtained data highlight the potential role of C. benghalensis as a new source of natural antioxidants and polyphenols compared to C. arabica.
authors.affiliation: Institute of Pharmacognosy, Medical School, University of Pécs, Rókus 2, Pécs, 7624, Hungary.
authors.forename: Éva Brigitta
authors.initials: ÉB
authors.lastname: Patay
authors.affiliation: Department of Laboratory Medicine, Medical School, University of Pécs, Ifjúság 13, Pécs, 7624, Hungary; János Szentágothai Research Center, Ifjúság 20, Pécs, 7624, Hungary.
authors.forename: Nikolett
authors.initials: N
authors.lastname: Sali
authors.affiliation: Department of Laboratory Medicine, Medical School, University of Pécs, Ifjúság 13, Pécs, 7624, Hungary; János Szentágothai Research Center, Ifjúság 20, Pécs, 7624, Hungary.
authors.forename: Tamás
authors.initials: T
authors.lastname: Kőszegi
authors.affiliation: Institute of Pharmacognosy, Medical School, University of Pécs, Rókus 2, Pécs, 7624, Hungary.
authors.forename: Rita
authors.initials: R
authors.lastname: Csepregi
authors.affiliation: Institute of Pharmacognosy, Medical School, University of Pécs, Rókus 2, Pécs, 7624, Hungary.
authors.forename: Viktória Lilla
authors.initials: VL
authors.lastname: Balázs
authors.affiliation: Department of Pharmacognosy, Faculty of Medicine and Pharmacy, University of Oradea, Piaţa 1 Decembrie u. 10, Oradea, 410073, Romania.
authors.forename: Tibor Sebastian
authors.initials: TS
authors.lastname: Németh
authors.affiliation: Department of Pharmacognosy, Faculty of Medicine and Pharmacy, University of Oradea, Piaţa 1 Decembrie u. 10, Oradea, 410073, Romania.
authors.forename: Tibor
authors.initials: T
authors.lastname: Németh
authors.affiliation: Institute of Pharmacognosy, Medical School, University of Pécs, Rókus 2, Pécs, 7624, Hungary. Electronic address: nora4595@gamma.ttk.pte.hu.
authors.forename: Nóra
authors.initials: N
authors.lastname: Papp
keywords: 2,2-Diphenyl-1-picrylhydrazyl; Coffee; Enhanced chemiluminescence; Folin-Ciocalteau; Oxygen radical absorbance capacity; Total tannin method