Min Jung Kim

Background: Heat-treated red ginseng contains pharmacologically active ginsenosides such as Rg5 and Rk1 and is increasingly used as a functional food. Because herbal products are frequently co-administered with conventional medications, evaluation of potential cytochrome P450 (CYP)-mediated drug–drug interactions is essential. This study examines their effects on nine cytochrome P450 isoforms to evaluate potential drug–drug interactions. Methods: The CYP enzyme inhibition method was assessed by determining IC50 values using human liver microsomes and specific substrates. Various concentrations of ginsenosides Rg5 and Rk1 were tested, and the reactions were analyzed via UPLC-MS/MS. Positive control inhibitors were included for comparison. Results: Ginsenoside Rg5 and Rk1 exhibited potent inhibitory effects on CYP2A6, with IC50 values of 1.04 and 0.98 μM, respectively, with moderate inhibitory effects observed for several other CYP activities and little or no inhibition observed for the remaining CYP activities. Conclusions: The results indicate potential adverse drug reactions with CYP2A6-metabolized drugs, highlighting the need for further in vivo safety evaluations. These findings provide important information regarding CYP-mediated herb–drug interaction potential associated with heat-processed ginsenosides.

Bitterness limits the development of palatable foods containing bioactive ingredients. This study investigated whether long-chain fatty acids (LCFAs) modulate the human bitter taste receptor TAS2R16 using a HEK293T cell-based calcium assay with salicin as an agonist. None of the tested LCFAs directly activated TAS2R16. Under co-treatment, only oleic acid inhibited salicin-induced calcium responses, shifting the salicin EC50 from 1.82 ± 0.11 mM to 3.55 ± 1.22 mM at 30 μM (p < 0.01). Pretreatment with all LCFAs inhibited TAS2R16 concentration-dependently. Reliable IC50 values were obtained for palmitic acid (8.67 ± 1.44 μM), stearic acid (0.082 ± 0.002 μM), and oleic acid (0.41 ± 0.12 μM), whereas lower plateaus were not reached for myristic, linoleic, and α-linolenic acids. LCFA treatment did not consistently change membrane fluidity, and inhibition was attenuated in the TAS2R16 N96T mutant. These findings demonstrate compound- and treatment-dependent modulation of TAS2R16 by food-derived LCFAs.

Visual cues play an important role in food selection by providing early information about taste properties before consumption. However, the large-scale neural mechanisms underlying the perception of different tastes from visual food cues remain poorly understood. Using electroencephalography and whole-brain functional connectivity analysis, we conducted an exploratory, hypothesis-generating investigation of large-scale brain network responses to visual food cues associated with three basic taste qualities, including sweet, sour, and salty. We computed functional connectivity across 100 cortical parcels, and examined the distribution of significant connections across seven canonical brain networks. Brain network connectivity differed across taste categories. Sweet food images engaged default mode network connectivity with somatomotor and attention networks. Sour food images showed significant limbic and salience network connectivity, suggesting heightened affective evaluation. Salty food images evoked the most widespread engagement, with significant control network involvement alongside visual, default mode, and attention networks. Our findings suggest that large-scale network interactions vary with the inferred taste profile of visual food cues. This network-level characterization provides exploratory evidence for taste-associated brain-wide communication during visual food processing.

Lemon myrtle essential oil (LMEO), a popular food-flavoring and perfume, has anti-inflammatory and antioxidant properties, and contains citral in abundance. Citral-enriched essential oils exhibit anti-obesity effects; however, the effect of LMEO on adipogenesis and the precise mechanism of citral have not been elucidated. This study evaluated the anti-adipogenic activity of commercial LMEO and its components, geranial, neral and citral (a mixture of geranial and neral), in 3T3-L1 cell differentiation and identified the anti-adipogenic mechanism of citral. Treatment of 3T3-L1 preadipocytes with various concentrations of LMEO, neral, geranial, and citral for 24 h and 48 h showed that LMEO (12.5–25 μg/mL) inhibited 3-isobutyl-1-methylxanthine, dexamethasone, and insulin (MDI)-induced differentiation of preadipocytes. Citral, accounting for 88.67% of total compounds in LMEO, also suppressed MDI-induced differentiation and expression of adipogenic transcription factors (PPARγ, C/EBPα, and Fabp4). Additionally, citral inhibited the early stages of differentiation, particularly mitotic clonal expansion (MCE), by deactivating cell cycle-related factors (cyclins and cyclin-dependent kinases) and arresting the cell cycle at G0/G1 phase, which was caused by inhibiting upstream signaling pathways, especially PI3K/AKT pathway. Therefore, regulation of early stages of adipogenesis, especially MCE, is a key mechanism underlying the anti-adipogenic activity of citral. LMEO and citral can be potentially used as anti-obesity agents.

Journal of Animal Science and Technology (JAST) is a peer-reviewed, open access journal publishing original research, review articles and notes in all fields of animal science. Topics covered by the journal include: genetics and breeding, physiology, nutrition of monogastric animals, nutrition of ruminants, animal products (milk, meat, eggs and their by-products) and their processing, grasslands and roughages, livestock environment, animal biotechnology, animal behavior and welfare.