How Do Reference Points Influence the Representation of the N200 for Consumer Preference?

Recent studies have suggested that event-related brain potential (ERP) can represent consumer preference, and there is consensus that the N200 is the best indicator of consumer preference. Measurement of reference-dependent consumer preference, in turn, requires a reference point, but it remains largely unknown how reference points modulate the preference-related N200. We designed an experiment to investigate how reference points affect the N200 based on classical paradigms. In the single-reference condition, one product was displayed in each trial; in the conjoined-reference condition, a pair of products was displayed simultaneously. Our results showed that in the single-reference condition, low-preference products elicited more negative N200 than high-preference products, replicating previous results, but the N200 could not distinguish between low- and high-preference products when viewing two options of similar subjective value in the conjoined-reference condition. These findings suggest that reference points modulate the representation of the N200 on consumer preference. When only viewing one product, participants make a value judgment based on their expectations. However, when viewing two products simultaneously, both their expectation and the alternative product can serve as reference points, and whether the N200 can represent consumer preference depends on which reference point is dominant. In future research, reference points must be controlled when the N200 is used to explore value-related decision-making.

Preparation of a crosslinked bioimprinted lipase for enrichment of polyunsaturated fatty acids from fish processing waste.

Geotrichum sp. lipase modified with a combined method composed of crosslinking and bioimprinting was employed to selectively hydrolyze waste fish oil for enrichment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in glycerides. Crosslinked polymerization by monomer (polyethylene glycol 400 dimethyl acrylate), crosslinker (trimethylolpropane trimethylacrylate), and photoinitiator (benzoin methyl ether) coupled to bioimprinting using palmitic acid as imprint molecule, resulted in much more effective enzyme preparation used in aqueous hydrolysis reaction. Since the crosslinked polymerization modification maintained bioimprinted property and gave good dispersion of enzyme in reaction mixture, the crosslinked bioimprinted enzyme exhibited higher hydrolysis temperature, enhanced specific activity, shorter hydrolysis time, and better operational stability compared to free lipase. Crude fish oil was treated at 45 degrees C with this crosslinked bioimprinted lipase for 8 h, and 46% hydrolysis degree resulted in the production of glycerides containing 41% of EPA and DHA (EPA+DHA), achieving 85.7% recovery of initial EPA and DHA. The results suggested that bioimprinted enzymes did not lose their induced property in aqueous environment when prepared according to the described crosslinking-bioimprinting method. It could also be seen that the crosslinked bioimprinted lipase was effective in producing glycerides that contained a higher concentration of polyunsaturated fatty acid with better yield.