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The increase in population-related and environmental issues has emphasized the need for more efficient and sustainable production strategies for foods and chemicals. Carbohydrates are macronutrients sourced from crops and undergone transformation into various products ranging from foods to chemicals. Continuous efforts have led to the identification of a promising hybrid system that couples the electrochemical reduction of CO2 to intermediates containing one to three carbons (C1–3) with the transformation of the intermediates using engineered microorganisms into valuable products. Here we use yeast to transform C1–3 substrates into glucose and structurally tailored glucose derivatives, such as the sugar alcohol myo-inositol, the amino monosaccharide glucosamine, the disaccharide sucrose and the polysaccharide starch. By metabolic rewiring and mitigation of glucose repression, the titre of glucose and sucrose reached dozens of grams per litre. These results provide directions for microbial sugar-derived foods and chemicals production from renewable reduced CO2-based feedstocks. [Figure not available: see fulltext.].

ObjectiveApplying the in vivo Mammalian Alkaline Comet Test， this study aimed to investigate the DNA damage caused by the food additive titanium dioxide and nano-titanium dioxide on rat liver cells.MethodsAccording to the guideline “In vivo mammalian alkaline comet assay” （OECD TG489）， male SD rats were randomly divided into nine groups，five rats per group. Food additive titanium dioxide was administered to three groups at doses of 1000， 500 and 250 mg/kg·BW， while pure water served as the negative control. Titanium dioxide nanoparticle was administered in three different doses： 500， 150， and 50 mg/kg·BW. The negative control group received 0.8% Tween + 3% FBS. Test substances were administered by gavage once a day for 15 d. Simultaneously， a positive control group was established， and the positive substance ethyl methyl sulfonate （EMS） was administered once daily on the 14th and 15th days via gavage， at a dosage of 200 mg/kg·BW·d. Animals were anesthetized six hours after the last administration，and the livers were harvested to prepare single-cell suspension smears. The sections were subsequently subjected to lysis，unwinding， electrophoresis， staining to acquire the comet images for analyzing.ResultsThere were no statistical differences （P>0. 05） in the percentages of tail DNA content between the treated and negative control rats. However， the percentage of tail DNA content of rat liver cells in the EMS group showed a significant difference compared to the negative control group （P

Understanding how students decide whether to participate during collaborative learning activities and what factors are their main concerns is important for efficient use of such activities in or out of the classroom. Based on evolutionary game theory, this study proposed a game model for collaborative learning that aimed to analyze the dynamic process by which bounded rational students adapt their strategies in collaborative learning. Based on the analysis of evolutional stable strategy in the model, the results identified perceived academic value, social gains, and social loss as motivators resulting in collaboration, while the cost of effort and time acted as the major barrier to collaborative learning. In addition, this study focused on the joint influence of these factors on students' collaborative learning behavior. It further provided several implications for developing theory-building of collaborative learning and educational policymaking.

The development of undergraduate students' soft skills is crucial because their chances to satisfactorily deal with the demands of various environments and interlocutors increases with the development of their soft skills. Based on the achievement goal theory, this study aimed to examine the role of the school environment in fostering students' soft skills. Structural equation modeling was conducted to examine the relationships between five environmental factors--learning task, teacher support, extracurricular activities, interaction with teachers and peers, and soft skills. These findings positively predicted soft skills in college environments with development and competence growth, for both in-class and out-of-class contexts. In addition, the findings revealed that the most effective methods to facilitate students' soft skills development included supporting extracurricular activities, engaging students in high-order learning tasks, facilitating peer learning, and providing structured guidance.

ObjectiveTo establish a zebrafish larva model for identifying antioxidants and screen candidate substances.MethodsZebrafish larvae with 3 d post fertilization （dpf） were treated with the fish culture water containing 12 known antioxidants， 2 oxidants and 4 candidate substances for 20 h. The maximum tolerant concentration （MTC） was determined by the acute toxic effect including death. With the highest dose of MTC， different dosages of tested substance were used to treat 3dpf larvae respectively， and the reactive oxygen species （ROS） indicator CM-H2DCFDA was added to the water at the same time. After 20 h treatment， fluorescent density was detected to calculate ROS clearance rate.ResultsEleven tested known antioxidants showed lower fluorescent density in treated zebrafish larvae compared to the control， which suggested their ROS clearance potency. Two oxidants increased the fluorescent density， and three of four candidate substances were found to decrease fluorescent density in zebrafish larvae.ConclusionThe study provided a sensitive test system for screening candidate antioxidants. The system was used to screen the products developed in the laboratory， and the results showed that it had certain application value.

ObjectiveThe risk assessment model of fatty liver accumulation in zebrafish larvae was established to identify the hepatotoxicity hazards of plasticizer butyl benzyl phthalate （BBP） using Di （2-ethylhexyl） phthalate （DEHP） and dibutyl phthalate （DBP） as positive control samples. This model was used to identify hepatotoxicity of butyl benzyl phthalate （BBP）.MethodsThe fatty liver signal intensity and expression of peroxisome proliferator activated receptor （PPAR） target gene CD36 in zebrafish liver after DEHP and DBP exposure were analyzed， and the hepatotoxicity model of zebrafish larvae was preliminarily constructed， which was used to evaluated the hepatotoxicity of BBP. In addition， liver density analysis， TG quantitative detection of zebrafish larvae and liver pathological examination of adult zebrafish were used to further verify the reliability of the model. The benchmark dose method （BMD） was used to derive the point of departure.ResultsDEHP and DBP showed significant risk of fatty liver induction （both P

ObjectiveTo establish the Food Toxicology Database （FoodTox）.MethodsA food toxicology database website was established. The priority list of the database was determined. The toxicological data of related substances through literature search was collected， and the systematic literature review （SLR） method was used to sort out the toxicological data of the substances in the library.ResultsThe food toxicology database has collected more than 1 600 substances with related data including toxicology-related information such as metabolism， acute toxicity， genotoxicity， reproductive and developmental toxicity， subchronic toxicity， chronic toxicity and carcinogenicity， population data， health guidance values and regulations of domestic and foreign management， related foods and symptoms etc.， which has been open to researchers in related fields.ConclusionThis database will provide the related professionals with the first-hand data， rapid technical support for emergency risk assessment and reference for priority substance evaluation.