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Quantitative descriptive sensory analysis (QDSA), gas chromatography-ion mobility spectrometry (GC-IMS) and Heracles NEO electronic nose (E-nose) combined with chemometrics were used for differential analysis of volatile compounds in essential oils (EOs) extracted from sweet orange peels (blood and navel) using cold pressing (CP), microwave-assisted hydrodistillation (MAHD) or spinning cone column (SCC). The results indicated that significant variations in flavor composition were found among the three EOs. The CP oil had the highest sensory preference with stronger fruity, sweet, and floral aromas. The MAHD oil had stronger fatty, green, and woody aromas, and the SCC oil had a lower aroma intensity. A total of 64 volatile components were identified by GC-IMS, terpenes, alcohols and aldehydes being the major ones, followed by acids, esters and other compounds. The fingerprint indicated that the contents of terpenes in the CP and MAHD oils were significantly higher than that in the SCC oil, whereas the contents of alcohols and aldehydes in the MAHD and SCC oils were significantly higher than those in the CP oil. Based on relative odor activity value (ROAV), β-myrcene and linalool were identified as the major contributors to the flavor of sweet orange EO. Moreover, using GC-IMS combined with partial least square discriminant analysis (PLS-DA) and variable importance in the projection (VIP), 13 differential volatile compounds were identified as aroma markers to distinguish among the 6 oils. Additionally, E-nose combined with principal component analysis (PCA) and discriminant factor analysis (DFA) also successfully distinguished among the 6 EOs according to their volatile compounds.

Self-assembly of the microtubule-associated protein tau into neurotoxic oligomers, fibrils, and paired helical filaments, and cell-to-cell spreading of these pathological tau species are critical processes underlying the pathogenesis of Alzheimer's disease and other tauopathies. Modulating the self-assembly process and inhibiting formation and spreading of such toxic species are promising strategies for therapy development. A challenge in investigating tau self-assembly in vitro is that, unlike most amyloidogenic proteins, tau does not aggregate in the absence of posttranslational modifications (PTM), aggregation inducers, or preformed seeds. The most common induction method is addition of polyanions, such as heparin; yet, this artificial system may not represent adequately tau self-assembly in vivo, which is driven by aberrant phosphorylation and other PTMs, potentially leading to in vitro data that do not reflect the behavior of tau and its interaction with modulators in vivo. To tackle these challenges, methods for in vitro phosphorylation of tau to produce aggregation-competent forms recently have been introduced ( Despres et al. ( 2017 ) Proc. Natl. Acad. Sci. U.S.A. , 114 , 9080 - 9085 ). However, the oligomerization, seeding, and interaction with assembly modulators of the different forms of tau have not been studied to date. To address these knowledge gaps, we compared here side-by-side the self-assembly and seeding activity of heparin-induced tau with two forms of in vitro phosphorylated tau and tested how the molecular tweezer CLR01, a negatively charged compound, affected these processes. Tau was phosphorylated by incubation either with activated extracellular signal-regulated kinase 2 or with a whole rat brain extract. Seeding activity was measured using a fluorescence-resonance energy transfer-based biosensor-cell method. We also used solution-state NMR to investigate the binding sites of CLR01 on tau and how they were impacted by phosphorylation. Our systematic structure-activity relationship study demonstrates that heparin-induced tau behaves differently from in vitro phosphorylated tau. The aggregation rates of the different forms are distinct as is the intracellular localization of the induced aggregates, which resemble brain-derived tau strains suggesting that heparin-induced tau and in vitro phosphorylated tau have different conformations, properties, and activities. CLR01 inhibits aggregation and seeding of both heparin-induced and in vitro phosphorylated tau dose-dependently, although heparin induction interferes with the interaction between CLR01 and tau.

Food sensory evaluation mainly includes explicit and implicit measurement methods. Implicit measures of consumer perception are gaining significant attention in food sensory and consumer science as they provide effective, subconscious, objective analysis. A wide range of advanced technologies are now available for analyzing physiological and psychological responses, including facial analysis technology, neuroimaging technology, autonomic nervous system technology, and behavioral pattern measurement. However, researchers in the food field often lack systematic knowledge of these multidisciplinary technologies and struggle with interpreting their results. In order to bridge this gap, this review systematically describes the principles and highlights the applications in food sensory and consumer science of facial analysis technologies such as eye tracking, facial electromyography, and automatic facial expression analysis, as well as neuroimaging technologies like electroencephalography, magnetoencephalography, functional magnetic resonance imaging, and functional near‐infrared spectroscopy. Furthermore, we critically compare and discuss these advanced implicit techniques in the context of food sensory research and then accordingly propose prospects. Ultimately, we conclude that implicit measures should be complemented by traditional explicit measures to capture responses beyond preference. Facial analysis technologies offer a more objective reflection of sensory perception and attitudes toward food, whereas neuroimaging techniques provide valuable insight into the implicit physiological responses during food consumption. To enhance the interpretability and generalizability of implicit measurement results, further sensory studies are needed. Looking ahead, the combination of different methodological techniques in real‐life situations holds promise for consumer sensory science in the field of food research. [ABSTRACT FROM AUTHOR]

The stability of Glycyrrhiza polysaccharide / casein complex was analyzed by Zeta potential and turbidity, and the structural properties and interaction mechanism of GP/CS complex were investigated by fluorescence spectrum, infrared spectrum and circular dichroism spectrum, ect. The emulsifying stability of compound emulsion was also discussed. The results showed that GP/CS could form a stable complex. When pH=7, the Zeta potential values of GP/CS complexes were between CS and GP solution, with the average particle size increasing and fluorescence intensity decreasing, and the ultraviolet absorption intensity decreasing with blue shift, the intensity and peak width of the absorption peak of the infrared spectrum were changed, and the secondary structure of casein were changed. The electrostatic interaction, hydrogen bonding and hydrophobicity were involved in the formation of the composites. In addition, GP/CS complex could improve the stability of the emulsion. This study provides reference for the application of protein-polysaccharide complex in food field. [ABSTRACT FROM AUTHOR]