highly significantp < 0.01
a decreasing trendp < 0.05
In general terms (in both ZnO/PLA and ZnO@PDA/PLA composites), there is a decreasing trend in total bacterial growth (p < 0.05 when each composite is compared with pure PLA) and, in the case of 3% ZnO/PLA, the difference is statistically highly significant (p < 0.01).