To the original BHE extract containing all groups of compounds. According to our chemical analyses, the CHCl3 fraction contains alkaloids, triterpenes and 7-deoxyloganic acid, the latter also found in the BuOH fraction, along with antioxidant substances such as phenolic glycosides and anthocyanidins. These observations are further supported by the DPPH results, which point out the BHE extract as the most effective free radical scavenger. Significant antioxidant activity in the BuOH fraction was detected, while the CHCl3 fraction had no antioxidant activity whatsoever. The results of this assay are in accordance to the aforementioned composition of these three substances and are adequate for the testing of our hypothesis. Expressive reduction in tumour weight and volume was observed in W256 tumour-bearing rats treated with both BHE extract and BuOH fraction. This restriction of tumour development was directly related with TWS119 increase in the survival rate, as shown in the figure 8B. All and two thirds of the rats treated with the BHE extract and BuOH fraction, respectively, survived for the tested period, while none of the animals treated with the CHCl3 fraction nor those who received vehicle survived. These results clearly show that by fractioning U. tomentosa extracts, active compounds that present anti-neoplastic effects are also separated, as well as constitute evidence of the importance of the oxidative stress modulation as part of the action mechanisms of this plant. The results obtained with the in vivo oxidative stress parameters also confirmed these findings. SOD and LPO measures in the liver and tumour tissue demonstrated a major beneficial effect of the U. tomentosa BHE extract and BuOH fraction, while the CHCl3 fraction consistently Tofacitinib JAK inhibitor produced negligible results. It is noteworthy that the BHE extract was significantly more successful than its BuOH fraction in heightening hepatic SOD levels, which were already increased in the control group as compared to the baseline group as a natural reaction to the considerable oxidative stress caused by the neoplastic process. Regarding Cat measures in both tissues, only the BHE extract achieved a statistically significant effect as compared to control, effectively increasing hepatic Cat levels to similar values as those of the baseline group. Despite the evident lower levels of GSH in tumour tissue found in the BHE extract and BuOH fraction-treated groups as compared to control, only those of the BHE extract were statistically significant. This is a favourable result, taking into account the important role that GSH plays in such cellular processes as the transport of amino acids, the synthesis of proteins and DNA, and even cellular detoxification. It seems appropriate to establish that the biological activities of U. tomentosa are indeed enhanced by the synergic action of its various components. It is remarkable to acknowledge that U. 
tomentosa seems to exert a degree of selectivity over its site of action, an observation which supports our previous findings. Indeed, in various parameters we observed that the BHE extract had different, if not opposite effects in the liver and tumour tissue. Even more important is the fact that this selectivity resulted in an apparent protection of the hepatocytes, which came along with a simultaneous attack to the neoplastic cells.