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Carotenoids are natural pigments that contribute to light harvesting and photo-protection in photosynthetic organisms. In this study, we analyzed the carotenoid profiles, including mono-hydroxy and epoxy-carotenoids, in the economically valuable red seaweed Pyropia yezoensis, to clarify the detailed biosynthetic and metabolic pathways in the order Bangiales. P. yezoensis contained lutein, zeaxanthin, α-carotene, and β-carotene, as major carotenoids in both the thallus and conchocelis stages. Monohydroxy intermediate carotenoids for the synthesis of lutein with an ε-ring from α-carotene, α-cryptoxanthin (β,ε-caroten-3’-ol), and zeinoxanthin (β,ε-caroten-3-ol) were identified. In addition, β-cryptoxanthin, an intermediate in zeaxanthin synthesis from β-carotene, was also detected. We also identified lutein-5,6-epoxide and antheraxanthin, which are metabolic products of epoxy conversion from lutein and zeaxanthin, respectively, by LC-MS and 1H-NMR. This is the first report of monohydroxy-carotenoids with an ε-ring and 5,6-epoxy-carotenoids in Bangiales. These results provide new insights into the biosynthetic and metabolic pathways of carotenoids in red seaweeds.

Fructophilic lactic acid bacteria (FLAB) are a group of lactic acid bacteria (LAB) with unique growth characteristics and are regarded as promising candidates for foods or food ingredients. The present study characterized levels of viable FLAB cells in honeybee-based food products, especially focusing on fresh honey. FLAB were recovered from 88% of fresh honey samples (harvested within a week) tested, and 29% of the fresh honey samples contained FLAB with levels of over 105 CFU/g. FLAB species found in the tested fresh honeys were mostly Apilactobacillus kunkeei and Fructobacillus fructosus. FLAB were not recovered from aged honey samples (aged over 2 weeks after harvest). Fresh comb honey and bee pollen samples occasionally contained low levels of FLAB. When FLAB were inoculated into honeys (linden honey and clover honey), their viability markedly reduced during a week. One of the reasons for this decrease was presence of H2O2 in the honeys, and supplementation of catalase significantly improved their survivability in linden honey. The long history of human consumption of fresh honey suggests that viable FLAB cells do not present health concerns.

Scope Fucoxanthin is converted to fucoxanthinol and amarouciaxanthin A in the mouse body. However, further metabolism such as cleavage products (i.e., apocarotenoids) remains unclear. The fucoxanthin‐derived apocarotenoid in vivo is investigated and the anti‐inflammatory effect of apocarotenoids with fucoxanthin partial structure such as allenic bond and epoxide residue against activated macrophages and adipocytes in vitro is evaluated. Methods and Results LC‐MS analysis indicates the presence of paracentrone, a C31‐allenic‐apocarotenoid, in white adipose tissue of diabetic/obese KK‐Ay and normal C57BL/6J mice fed 0.2% fucoxanthin diet for 1 week. In lipopolysaccharide‐activated RAW264.7 macrophages, paracentrone as well as C26‐ and C28‐allenic‐apocarotenoids suppresses the overexpression of inflammatory factors. Further, apo‐10′‐fucoxanthinal, a fucoxanthin‐derived apocarotenoid which retained epoxide residue, exhibits a most potent anti‐inflammatory activity through regulating mitogen‐activated protein kinases and nuclear factor‐κB inflammatory signal pathways. In contrast, β‐apo‐8′‐carotenal without allenic bond and epoxide residue lacks suppressed inflammation. In 3T3‐L1 adipocytes, paracentrone, and apo‐10′‐fucoxanthinal downregulate the mRNA expression of proinflammatory mediators and chemokines induced by co‐culture with RAW264.7 cells. Conclusion Dietary fucoxanthin accumulates as paracentrone as well as fucoxanthinol and amarouciaxanthin A in the mouse body. Allenic bond and epoxide residue of fucoxanthin‐derived apocarotenoids have pivotal roles for anti‐inflammatory action against activated macrophages and adipocytes.

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