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Erythorbyl oleate (EO), a novel emulsifier with multifunctional properties, was synthesized via lipase‐catalyzed solvent‐free esterification between erythorbic acid and oleic acid. The reaction produced EO of 30.75 ± 1.65 mM at 60 h, monitored by high‐performance liquid chromatography (HPLC) analysis. Purified EO was chemically identified as 6‐O‐oleoyl‐erythorbic acid by HPLC‐electrospray ionization/mass spectrometry (ESI‐MS), 1H nuclear magnetic resonance (NMR), and 13C NMR analyses, and further investigations on its multifunctionalities were conducted. EO displayed antioxidant activity equivalent to erythorbic acid in 2,2‐diphenyl‐1‐picrylhydrazyl and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radical scavenging activities. Investigation of the antibacterial activity of EO against foodborne pathogens showed MICs of 0.27 ± 0.09 and 0.40 mM for Bacillus cereus ATCC 10876 and Staphylococcus aureus ATCC 12692, respectively. EO also displayed interfacial properties, lowering interfacial tension between medium‐chain triglyceride oil and water to 3.40 ± 0.04 mN/m with a critical micelle concentration of 2.54 ± 0.03 mM. Dynamic light scattering analyses of the emulsion stabilized by EO demonstrated a similar polydispersity index (0.15 ± 0.00) to Tween 80‐stabilized emulsion (0.28 ± 0.01), with an average droplet size of 173.2 ± 1.8 nm. In addition, the EO‐stabilized emulsion exhibited a negative surface charge (−56.83 ± 4.30 mV) in zeta potential measurements, indicating sufficient electrostatic repulsion between droplets. These results suggest that EO is a multifunctional emulsifier to simultaneously control oxidative rancidification and bacterial spoilage in emulsion‐based foods. Practical Application: EO was synthesized via an enzymatic esterification reaction between erythorbic acid and oleic acid. The synthetic process excluded any use of organic solvent, diminishing potential health hazards or environmental pollution associated with chemical reactions. The interfacial properties of the resultant EO, along with excellent antioxidant and antibacterial activities, propose its potential application in emulsion‐based foods. Simultaneous control of bacterial spoilage and oxidative rancidification by EO would fulfill the industrial needs for extending shelf life and enhancing consumer safety. [ABSTRACT FROM AUTHOR]

Background: Pharmacological inhibition of aryl hydrocarbon receptor (AhR) activation after ischemia alleviates cerebral ischemia/reperfusion (IR) injury. Purpose: To investigate whether AhR antagonist administration after reperfusion was also effective in attenuating cerebral IR injury. Material and Methods: A total of 24 Sprague–Dawley rats were divided into the sham-operated group (no IR), control group (IR), and 6,2′,4′-trimethoxyflavone (TMF) group (IR + TMF administration), with 10 rats assigned to each group. Cerebral IR injury was induced by 60 min of middle cerebral artery occlusion followed by reperfusion. TMF (5 mg/kg) was used as the AhR antagonist and was administered intraperitoneally immediately after reperfusion. Cerebral IR injury was observed using magnetic resonance imaging (MRI) and neurobehavioral assessments at baseline, immediately after ischemia, and at 3 days after ischemia. Results: On MRI, the TMF group showed no significant differences in relative apparent diffusion coefficient (ADC), T2, and fractional anisotropy (FA) values; midline shift value; and infarct volume. In terms of neurobehavioral function, factors such as grip strength, contralateral forelimb use, time to touch, and time to remove adhesive tape from the forepaw, were also not significantly different between the control and TMF groups. Conclusion: This study demonstrated that AhR treatment after reperfusion had no noticeable effect on reducing cerebral IR injury in rats. [ABSTRACT FROM AUTHOR]

Climate change engendered by carbon emissions has become a major threat to human life and the world economy. Many of early studies corroborate that carbon tax and subsidy are effective policy tools to alleviate climate change. Most of them, however, use closed-economy models with a single firm to analyze the effects of these two policies. This paper explores the effects of carbon tax, subsidy and foreign carbon emissions on economic activities in an open macroeconomic model that features low- and high-carbon firms. The main findings suggest that carbon tax, subsidy and foreign carbon emissions all deliver heterogeneous outcomes by largely affecting high-carbon firms. The shortage of national income due to weak economic activities leads the economy to issue more international bonds. The takeaway from all the analyses is that government should introduce various carbon taxes that are geared towards target firms with different carbon emissions and adopt optimal means to manage national debt. [ABSTRACT FROM AUTHOR]

The literature on fiscal policy has identified wealth elasticity of labor supply and agent heterogeneity as the linchpin of shaping different transmission mechanisms for fiscal policy. In this paper, I build these two important edifices on an otherwise canonical business-cycle model to conduct quantitative analyses of various fiscal policies. To underscore the relative importance of agent heterogeneity, I compare results from the model with agent heterogeneity with those from a standard model without agent heterogeneity. I also compare results from changes in wealth elasticity to analyze how the model ingredient delivers different macroeconomic and fiscal dynamics. The main finding reveals that in the context of the model formulated in this paper, the capital tax is the least detrimental to business cycles and fiscal states and the consumption tax is the most appropriate policy tool since it yields positive output and tax-revenue multipliers in the short and long runs. All the results from counterfactual experiments suggest that macroeconomic and fiscal outcomes hinge fundamentally on agent heterogeneity and wealth elasticity. An important value that this paper adds to the literature is to offer results from a comprehensive analysis of all possible fiscal policies by considering both essential forces. [ABSTRACT FROM AUTHOR]