Antiproliferative potential of pinebark

The anti-tumour agents from natural sources attract growing attention in recent years. Therefore, a great number of plant species have been investigated in order to identify potent biological components. Pine bark as a valuable source of bioactive polyphenols presents an attractive raw material. The aim of the research was to investigate in vitro the antiproliferative effects of Pinus nigra Arnold bark. Pinus nigra Arn. bark was sampled from mountains Tara and Mokra Gora (Republic of Serbia). Cell growth effects of Pine bark were evaluated in human cervix epithelioid carcinoma (HeLa) and breast adenocarcinoma (MCF7) cell lines by measuring the total protein by colorimetric sulforhodamine B assay after 48h of incubation. Based on the obtained IC50 parameter (the concentration that inhibited the cell growth by 50%), pine bark from both localities impaired the growth of all investigated cell lines in the low concentration range (28-65 μg/mL). The highest activity was observed for Pinus nigra Arn. bark from Tara locality. In addition, in order to identify higher selectivity towards tumour cells compared to healthy tissue, non-tumour/tumour IC50 ratio (NT/T) was calculated. Bark from both localities showed the highest selectivity. The most encouraging NT/T ratio was obtained for breast adenocarcinoma cell lines.The obtained results suggest that Pinus nigra Arn. bark from Tara and Mokra gora locality are significant source of anti-tumour agents and as such, are recommended in the development of future anti-tumour or chemopreventive agents.