## 3 Results and Discussion
### Cytotoxic Properties of WSP  
It has been reported that many mushroom polysaccharides show direct cytotoxicity to cancer cells [62]. To determine the response of cells to water soluble mushroom polysaccharides (WSP) we used MTT assay that measures the reduction in cell viability when exposed to cytotoxic substances. The control T47D and MCF-7 cells viability was assessed as 100%. Our results showed a dose dependent cytotoxic effect of crude polysaccharide extract from _Lentius edodes_ on MCF-7 cells  
Figure 3: Antioxidant capacity of WSP.  
(Figure 4a). The control, a not processed WSP sample, caused a 73% and 41.7 \(\pm\) 4.7% decrease of MCF-7 cell viability after treatment with 50 and 250 \(\upmu\)g/mL concentration respectively. The processing of _Lentiinus edodes_ fruiting bodies particularly blanching and blanching with further fermentation had suppressed cytotoxic activity of applied WSP. After incubation with the highest polysaccharides concentration MCF-7 cells viability reached 74.0 \(\pm\) 5.7% and 82.5 \(\pm\) 3.5%, respectively. Boiling in water changed cytotoxic properties of polysaccharides in the least degree. MCF-7 cells viability after treating with (250 \(\upmu\)g/mL) WSP from boiled mushrooms was 57.9 \(\pm\) 5.8% [63]. [PERSON] et.al. achieved a 50% reduction in viability of MCF-7 cells, however the time of incubation with 73 \(\pm\) 14 \(\upmu\)g/mL of water extract from _Lentiinus edodes_ took 48 h. Moreover, it is known that whole mushroom extracts contain a lot of substances other than polysaccharides with very well documented direct cytotoxic activities achieved 50% reduction in viability of MCF-7 cells, however, the time of incubation with 73 \(\pm\) 14 \(\upmu\)g/mL of water extract from _Lentiinus edodes_ took 48 h. It is known that whole mushroom extracts contain a lot of substances other than polysaccharides with very well documented direct cytotoxic activities [64].  
In the cell line T47D (Figure 4b), we have assessed no significant sensitivity to polysaccharides fractions from processed and control (_Lentiinus edodes_ fruiting bodies) mushrooms. Viability of T47D cells treated with maximal WSP concentration was consecutively 87.2 \(\pm\) 4.5% for blanched, 84.9 \(\pm\) 0.6% for blanched with further fermentation and 83.7 \(\pm\) 1.8% for control sample. Interestingly boiling in water have led to complete loss of WSP antiproliferative activity (cells viability was 97.0 \(\pm\) 0.5%).  
These observations are consistent with the results of previous studies [23] carried out on _Pleurotus ostreatus_ fungus where it was stated that hydro-thermal processing of mushrooms cause  
Figure 4: Cytotoxic effect of water soluble polysaccharides (WSP) from blanched, boiled, blanched and fermented _Lentiinus edodes_ on MCF-7 (**a**) and T47D (**b**) cell lines.  
the loss of direct cytotoxic activity of mushroom derived polysaccharides. Similarly other authors reported that different ways of mushrooms conservation treatment and cooking affect the composition of nutritional values and their antioxidant properties [18]. To sum up, from both studied breast cancer cell lines MCF-7 and T47D, the first one seemed to be more sensitive to water soluble polysaccharides. The strongest antiproliferative activity to MCF-7 cells was stated for water soluble polysaccharides from non-processed _Lentiinus edodes_ fruiting bodies.