[Pini cembrae coni: histo-anatomical and chemical studies, assessment of antioxidant activity]

This study aimed to identify some histoanatomical features, to evaluate the polyphenolic content and antioxidant activity of cembran pine female cones.

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.

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.

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.