Integrated management of residues from tomato production: Recovery of value-added compounds and biogas production in the biorefinery context.

The biorefinery approach must be boosted in the management of agro-residues in the future. The present study aims to investigate the valorization of tomato production residues, namely rotten tomato (unfit for consumption - RT), green tomato (GT), and tomato branches (TB). The assessment involves the recovery of value-added compounds through the extraction process followed by biogas production through anaerobic digestion. A thorough characterization of the three residues (RT, GT, and TB) was carried out, including the identification of volatile compounds by solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS). The volatiles analysis revealed the presence of flavor enhancer compounds and molecules with insecticidal properties. A solid-liquid extraction with ethanol allowed the recovery of value-added compounds in the extracts, in particular phenolic compounds, ß-carotene, and lycopene, which contributed to the antioxidant activity. RT and TB extracts were found to be richer in total phenolic compounds (~27 mg GAE/gdb dry basis) and exhibited higher antioxidant activity (IC50 = 0.911 and 0.745 mg/mL). The tomato branches extract had the highest concentration of carotenoids with 37.23 and 3.08 mg/kgdb of ß-carotene and lycopene, respectively. The biochemical methane potential (BMP) was assessed in sealed reactors operating in anaerobic conditions for all the raw (RT, GT, and TB) and extracted substrates waste (RTe, GTe, and TBe). While the BMP of RT and GT was in the range of 232-285 mL CH4/g VS, a lower value of 141 mL CH4/g VS was obtained for TB. The methane production for each pair of raw and extracted substrates (RT/RTe, GT/GTe, and TB/TBe) was considered statistically similar at a 95 % confidence level. Overall, the value-added compounds recovery through ethanolic extraction did not compromise the methane production of the materials.

Role of serotonin 1A receptors in the median raphe nucleus on the behavioral consequences of forced swim stress.

Despite the intense research on the neurobiology of stress, the role of serotonin (5-HT)1A receptors still remains to be elucidated. In the hippocampus, post-synaptic 5-HT1A receptors activation induces anxiolytic effects in animals previously exposed to stressful situations. However, little is known about somatodendritic 5-HT1A receptors in the median raphe nucleus (MRN). Therefore, the aim of this study was to investigate the role of 5-HT1A receptors located in the MRN in rats exposed to forced swim stress. After recovering from surgery, rats were forced to swim for 15 min in a cylinder. Intra-MRN injections of saline, 8-OH-DPAT (3 nmol/0.2 µL) and/or WAY-100635 (0.3 nmol/0.2 µL) were performed immediately before or after pre-exposure or 24 h later (immediately before test). Non-stressed rats received the same treatment 24 h or 10 min before test. Our data showed that 8-OH-DPAT increased latency to display immobility while decreasing time spent immobile in almost all experimental conditions. These effects were not prevented by previous treatment with WAY-100635. No effects of different treatments were described in non-stressed animals. Taken together, our data suggest that in addition to activation of 5-HT1A, 5-HT7 receptors may also be involved in the behavioural consequences of exposure to swim stress.