This study aimed to identify some histoanatomical features, to evaluate the polyphenolic content and antioxidant activity of cembran pine female cones.
Material and methods: The cross sections, obtained by usual techniques, were examined using a Novex microscope with a Canon A95 digital camera. For chemical and antioxidant assays dried cones were extracted with 80% aqueous methanol. The total phenolics, flavonoids and proanthocyanidins in cone extract were quantified by spectrophotometric methods. The antioxidant activity was investigated using different in vitro assays: ABTS radical cation scavenging assay, reducing power assay and ferrous ion chelating ability assay.
Results: The histo-anatomical study of the seed-bearing scale revealed many secretory channels. The cone extract had low contents of total phenolics (48.03 +/- 0.10 mg/g), flavonoids (8.11 +/- 0.27 mg/g) and proanthocyanidins (1.63 +/- 0.03 mg/g). The extract scavenged ABTS radical cation and reduced ferric ions to ferrous ions with EC50 values of 64.6 +/- 0.8 and 118.60 +/- 1.89 microg/ml, respectively being less active than the positive control, quercetin (EC50 = 1.16 +/- 0.05 and 2.58 +/- 0.00 microg/ml, respectively). In ferrous ion chelating ability assay the extract showed a good activity (EC50 = 1.2 +/- 0.0 mg/ml) while quercetin was inactive.
Conclusions: The ability of cone extract to chelate ferrous ions encourages further studies for identification of bioactive constituents and evaluation of their protective effects against ferrous ion-induced oxidative stress.