This study was conducted to propose a suitable set of methods to evaluate the efficiency of two biotreatments. For this purpose, two sets of four 7.5 L bioreactors were followed over 90 days, containing natural sediments from the Bizerte Lagoon (Tunisia) contaminated with 35 mg·kg⁻¹ benzo(a)pyrene (BaP) and 28 mg·kg⁻¹ dichlorodiphenyltrichloroethane (DDT). One set was biostimulated with N/P and bioaugmented with the indigenous Pseudomonas stutzeri, Cupriavidus metallidurans and Rhodococcus equi, and the other set was only biostimulated. In the effluent, organic carbon decreased from 42 gC·L⁻¹ to 0.2 gC·L⁻¹ for the bioaugmented treatment compared to 15 gC·L⁻¹ for biostimulation. Statistical analyses confirmed a significant difference in BaP concentration after bioaugmention from 35 mg·kg⁻¹ to 21 mg·kg⁻¹ sediment, whereas no difference was found with biostimulation. Considering DDT, biostimulation was more efficient (8.5 mg·kg⁻¹ sediment final concentration) than bioaugmentation (15 mg·kg⁻¹ final concentration). Native organotin and metals were also monitored using bioluminescent bioreporter strains. The bioaugmented treatment brought about a significant decrease in TBT content, to below 0.01 µM, whereas its concentration remained significant after biostimulation. The biostimulation did not alter As³⁺, Cu²⁺, Cd²⁺, and Hg²⁺ concentrations, whereas bioaugmentation induced a decrease of 1 to 2 log for each metal. At the end of the experimental period, toxicity decreased to 90% in the effluent of the bioaugmented reactors compared with a drop of only 48% for biostimulation, and a significant decrease in mutagenicity appeared for bioaugmention only. Interestingly, not all the strains used in the treatments were maintained, as P. stutzeri and R. equi increased up to densities of 8.3 × 10¹³ and 5.2 × 10¹² DNA·g⁻¹ sediment, respectively, while in both treatments, C. metallidurans decreased down to the detection threshold. Among the different methods used, a restricted monitoring panel of analyses appears essential to follow the change occurring over the bioremediation process: (i) organic carbon measurement reporting all biodegradation events, as well as a specific method to monitor the main compounds; (ii) dissolved N, P, O₂ and pH measurements, (iii) a qPCR method to track the degraders; and (iv) measurements of the acute toxicity and the mutagenicity.

Food waste is one of the main problems contributing to climate change, as its piling up in landfills produces the greenhouse gas methane. Food waste occurs at every stage of food production; however, a major source of food waste occurs at businesses that supply food to consumers. Industry 4.0 technologies have shown promise in helping to reduce food waste in food supply chains. However, more innovative technologies, such as Raman spectroscopy, hold great promise in helping to reduce food waste, although this has largely been ignored in the literature. In this context, we propose a portable Raman platform to monitor food quality during transportation. The developed system was tested in conditions mimicking those present in a refrigerated truck by analyzing chicken samples stored at temperatures of 4 °C. Raman spectra were acquired for non-packaged and packaged samples over the duration of 30 days resulting in 6000 spectra. The analysis of Raman spectra revealed that the system was able to detect noticeable changes in chicken quality starting on day six. The main Raman bands contributing to this change are amide I and tyrosine. The proposed system will offer the potential to reduce food losses during transportation by consistently checking the food quality over time.