Anti‐Lipogenic Effects of Iridoid‐Rich Lonicera caerulea Berry Extracts in a Cortisol‐Stimulated Adipocyte Model

ABSTRACT Berries of Lonicera caerulea (blue honeysuckle; haskap) have been used since ancient times in traditional medicine in China, Japan, and northern Russia. This study aimed to extract, characterize, and evaluate the biological activity of iridoid‐rich fractions from haskap berries using an in vitro adipocyte model. Liquid chromatography‐mass spectrometry (UPLC–MS) analysis was performed to quantify the major iridoid distribution among ten haskap cultivars. Two iridoid‐enriched extracts were prepared via ultrasonication‐assisted ethanolic extraction followed by C 18 solid‐phase fractionation (Extract 1) and subsequent iridoid concentration (Extract 2). Functional evaluation was carried out using a cortisol‐induced 3T3‐L1 adipocyte model. UPLC‐MS revealed pronounced genotypic variation in iridoid profiles among ten cultivars, with CBS‐5 exhibiting the highest total iridoid content (2.42 mg/g dry weight), dominated by loganic acid. UPLC–MS confirmed loganin and loganic acid as the predominant constituents in both extracts. The iridoid‐rich extracts significantly attenuated cortisol‐induced lipid accumulation and intracellular reactive oxygen species generation in 3T3‐L1 adipocytes. Consistently, authentic standards of loganin and loganic acid exhibited pronounced antioxidant and anti‐lipogenic activities. Collectively, these findings indicate that iridoid‐rich extracts from L. caerulea berries may modulate lipid dysregulation and oxidative stress, supporting their potential development as functional food ingredients or nutraceuticals. Practical Applications Iridoid‐rich haskap berry extracts demonstrate anti‐lipogenic and antioxidant effects in adipocytes, highlighting cultivar selection and extraction strategies for developing functional foods or nutraceutical ingredients targeting stress‐related lipid dysregulation and metabolic health, with potential applications in disease‐prevention formulations and ingredient standardization.