Nutraceutical use of algae requires understanding of the diversity and significance of their active compositions for intended activities. Ishige okamurae (I. okamurae) extract is well-known to possess α-glucosidase inhibitory activity; however, studies are needed to investigate its active composition in order to standardize its α-glucosidase inhibitory activity. In this study, we observed the intensity of the dominant compounds of each I. okamurae extract harvested between 2016 and 2017, and the different potency of each I. okamurae extract against α-glucosidase. By comparing the anti-α-glucosidase ability of the dominant compounds, a novel Ishophloroglucin A with highest α-glucosidase inhibitory activity was identified and suggested for standardization of anti-α-glucosidase activity in I. okamurae extract. Additionally, a validated analytical method for measurement of Ishophloroglucin A for future standardization of I. okamurae extract was established in this study. We suggest using Ishophloroglucin A to standardize anti-α-glucosidase potency of I. okamurae and propose the significance of standardization based on their composition for effective use of algae as marine-derived nutraceuticals.

The metabolic pathway of phospholipids is one of the most important physiologic pathways in Mycobacterium tuberculosis , a typical intracellular bacterium. The hemolytic phospholipase lip gene (Rv0183) is one of 24 phospholipase genes that have been demonstrated to play critical roles in the metabolism of phospholipids in M. tuberculosis. Quantitative RT–PCR and flow cytometry were used to elucidate the immunological and pathogenic implications of the Rv0183 gene on the inflammatory response following persistent expression of Rv0183 in mouse alveolar macrophage RAW264.7 cells. Our results demonstrate that a time-course-dependent ectopic expression of Rv0183 significantly elevated the expression of IL-6, NF-κB, TLR-2, TLR-6, TNFα, and MyD88 in these alveolar macrophage cells. Furthermore, the persistent expression of Rv0183 induced RAW264.7 cell apoptosis in vitro. These findings demonstrate that the expression of Rv0183 induces an inflammatory response and cell apoptosis in the host cells, suggesting that Rv0183 may play an important role in the virulence and pathogenesis of M. tuberculosis infection.