# Quality and Safety of Dried Mushrooms Available at Retail Level
## 3 Results and Discussion
### Detection of Foodborne Pathogens  
_L. monocytogenes, Listeria_ and _Salmonella_ spp. were not detected in any sample of the dried mushroom samples in this study. On the other hand, the presence of _Salmonella_ spp. in dried mushrooms has been regularly reported [9; 11]. _L. monocytogenes_ was more commonly associated with fresh mushrooms, and both cultivated and wild mushrooms were affected [11; 12; 13; 14]. Presumptive BC were identified in 36 samples (59.0%). In dried mushrooms analyzed in Germany, pBC were isolated from 81.5% and, recently, 64.3% [8,10]. However, in our study, the pBC counts were low to moderate (1.0-3.4 log cfu/g). These results are consistent with previous reports that found pBC between 0.5 and 3.6 log cfu/g both for dried and fresh mushrooms [33,34]. According to the _panC_ gene sequencing and toxin gene typing, the 42 BC isolates were affiliated to the phylogenetic groups II, III, IV, V, and VI and toxin profiles A (_uhe+_, _hbl+_, _cytk2+_), C (_uhe+_, _hbl+_), D (_nhe+_, _cytk2+_), and F (_nhe+_) (Figure 2). Based on the PCR, none of the isolates were positive for the _ces_ gene, but in previous studies, BC isolates possessing the _ces_ gene were observed in both fresh (3.0%) and dried (8.1%) mushroom samples [8,34]. The _panC_ IV cluster in combination with toxin gene profile A was identified most frequently (52.8%/36 BC-positive samples) in our study and was observed in every group except _Pezizomycotina_. Subsequently, the _panC_ group toxin profile combinations VI/C, VI/F, II/C, and V/C were found in 19.4%, 13.9%, 11.1%, and 5.6% of the positive samples, respectively (Figure 2). This is in agreement with a study by [PERSON] et al. [26], who also found a predominance of the _panC_ cluster IV/A in 33.0% and VI/C in 10.4% of different food products. In fresh mushrooms, toxin gene profile A was also the most common (62%) among isolates [34]. Isolates assigned to toxin profile F in combination with _panC_ groups II, III, IV, and V were present in one sample each. The _cry  
Figure 1: Samples with microbiological values above the specified limits in at least one parameter A, purchased from online shops and Austrian supermarkets. Percentage (%) of total (\(n=61\)) and number of samples within each group. A \(\Delta\)MC, EB, yeasts, molds, and BC; B  this group represented different species without gills. gene, which is characteristic of _B. thuringiensis_, a species that also belongs to the BC group, was detected in only four (6.5%/42) of these isolates, associated to the mushroom samples of the _Agaricales_, _Agaricomycotina_ (wood ear mushroom), and _Chanterellales_ (Figure 2). _B. thuringiensis_ is present naturally in the environment, and defined subspecies use it as a biological insecticide to promote plant production [35]. Assessing the potential health risk posed by BC, the combination of enterotoxin profiles, the presence of the _ces_ gene, and the contamination level in the food has to be taken into account. In cell bioassays, the cytotoxic activity of the enterotoxin toxin profiles (A, C, D, and F) that were also found in this study appears to be variable and ranged from low to high [36]. Outbreaks were often associated with pBC counts above 5.0 log cfu/g in the foodstuff [37]. On the other hand, cases induced by lower BC counts could be traced back to strains encoding cereulide and diarral toxin genes [38]. The mushrooms investigated in the present study contained low BC counts, except for one _Boletus_ sample, which had a pBC count above the critical limit of 3.0 log cfu/g [20], and the _ces_ gene, which induces the pre-formation of the heat-stable emetic toxin cerebellar in food, was not detected in any BC isolate. Considering food safety issues, it is important to note that foodborne pathogens can survive the common drying technologies in fruits, vegetables, and mushrooms [4; 31; 39; 40; 41]. Current studies showed that after the drying process at 55 to 90 \({}^{\circ}\)C, the populations of _Salmonella_ spp., _L. monocytogenes_, and _B.