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Alkali pretreatment of anaerobic digestion (AD) was investigated as a strategy to degrade complex organic matter such as fats. AD of food waste (FW) with alkali pretreatment was conducted using batch assays and long-term experiments for 70 days in two reactors. The aim of this study was to compare the impact of alkali pretreatment on solubilization and biogas production and to evaluate the performance in reactors with that of the untreated FW. The alkali pretreatment enhanced the solubilization of organic matter. The best biogas yield (829 mL/g VS) and methane content (65.48%) were obtained by the pretreatment with 1% CaO with the highest P i, n (66.06%) of biodegradable soluble materials. The long-term reactors with pretreatment performed more steadily with higher biogas production under organic loading rates (OLR) over 5 g VS/(L⋅d). The bacterial community structure was different under various conditions. Methanosaeta and Methanospirillum were the dominant archaea in this study, while Methanosaeta increased in R1 at OLR of 6 g VS/(L⋅d). The study concluded that alkali pretreatment with 1% CaO appeared as a potential strategy for AD of FW., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In order to study the e of formaldehyde exposure on learning and memory ability of mice. We used Kun Ming (KM) mice to demonstrate the neurotoxic effects of FA, and Balb/c mice to explore the neurobiological mechanism. The Morris water maze (MWM) test showed that the exposure of gaseous formaldehyde could cause spatial learning and memory impairment in mice. H & E staining showed that in the 3.0 mg/m 3 formaldehyde exposed group, the arrangement of pyramidal cells in CA1 area of mouse hippocampus was loose and disordered, the cell morphology was swollen and deformed, and the apical dendrites were shortened or even disappeared. Biochemical indicators revealed high doses of FA exposure could cause oxidative damage in brain. Compared with the control group, there were significant differences in the levels of ROS, MDA, GSH and 8-OHDG in the 3.0 mg/m3 group (P < 0.01), also the monoamine neurotransmitters content and the content of TNF-α, IL-1β and Caspase-3 (P < 0.01). Furthermore, the concentrations of cAMP, cGMP, NO and the activity of NOS in the cerebral cortex, hippocampus and brain stem after high doses of FA exposure were significantly different from those in the control group, indicating that FA exposure could interfere with the transduction of NO/cGMP signaling pathway. The results showed that FA could induce cognitive deficits and this extended investigation found that the toxicity of FA to the mouse nervous system is related to the NO/cGMP and cAMP signaling pathways., Competing Interests: Declaration of competing interest The authors declare no conflict of interest. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)