## 3 Results
### Bacterial Biodiversity
The DNA sequence reads obtained were assigned to operational taxonomic units (OTUs). OTUs were grouped by taxonomic level. The mean values of sample replicates are shown. The statistical analysis of the differences in the main bacterial groups found in the pure samples with or without treatments is shown in Figure 5. _Enterobacteriaceae_ (others) had relative abundances of 40% in both the control sample and in the sample inoculated with _Paenibacillus_; however, this percentage decreased significantly (\(p<\) 0.05) to 20% when treated with eluate E and 30% when treated with eluate A. Genus _Pseudomonas_ was represented with quite similar percentages of approximately 20%, both in the control and in the sample inoculated with _Paenibacillus_, but instead it increased up to 50% in the sample treated with _Paenibacillus_. Figure 4: Global comparison of the means of biodiversity percentages obtained for the main taxonomic levels found in the puree samples, represented with Krona tools. (**A**) Untreated controls. (**B**) Puree inoculated with _Paenibacillus dendritiformis_ UJA2219. (**C**) Puree treated with partially-purified extract (1.5 M eluate). (**D**) Puree treated with partially-purified extract (60% acetonitrile). eluate E and decreased significantly (\(p\) < 0.05), almost to zero, in the sample treated with eluate A. For the genera _Acinetobacter_ and _Enterobacter_, which represented between 10% and 14% of the total OTUs, treatment with the NaCl eluate reduced their relative abundances by at least half. The relative abundance of _Acinetobacter_ increased after _Paenibacillus_ inoculation or treatment with acetonitrile eluate. The treatment with the acetonitrile eluate (A) significantly (\(p\) < 0.05) increased the relative abundance of _Bacillus_, _Enterococcus_ and _Lactococcus_. Treatment with NaCl eluate significantly (\(p\) < 0.05) decreased the population of _Enterococcus_ while it significantly (\(p\) < 0.05) increased that of _Stenotrophomonas_. The differences between samples were also analyzed comparing the global results of relative abundances at the genus level using principal coordinate analysis (PCoA). The results (Figure 6) revealed that the control sample and the sample inoculated with _Paenibacillus_ are very similar; however, there is a large difference between the samples treated with the eluates with respect to the control and to each other. Figure 5: Comparison of the differences in relative abundance of the most representative genera found in the puree samples. Y axis represents relative abundance (average of three replicates \(\pm\) standard deviation). X axis indicates sample type (C, controls; P, treatment with _Paenibacillus_ strain; E, treatment with NaCl eluate; A, treatment with acetonitrile eluate. Asterisk denotes statistically significant (\(p\) < 0.05) differences with controls. Each graphic represents a different genus or taxonomic group: (**A**) _Pseudomonas_; (**B**) fam. _Enterobacteriaceae_ (others); (**C**) _Acinetobacter_; (**D**) _Enterobacter_; (**E**) _Bacillus_; (**F**) _Enterococcus_; (**G**) _Klebsiella_; (**H**) _Lactococcus_; (**I**) _Stenotrophomonas_.