## 3 Results
### Effects of TA and LC on Inflammation Markers in DSS-Treated Mice  
Serum lipocalin-2 serves as a reliable marker of inflammation. In comparison to DSS-treated mice, lipocalin-2 levels exhibited a decrease of 21.2% in DTA, 17.80% in DLC, and 55.7% in DTL, with the DTL group demonstrating the most substantial reduction (Figure 4A). Markers of UC, encompassing inflammation-related cytokines such as IL-6, TNF-\(\alpha\), and IFN-\(\gamma\), representative of intestinal epithelial cells, were evaluated in colon tissue. The level of IFN-\(\gamma\) demonstrated a decrease of 44.2% in DTA, 39.3% in DLC, and 47.1% in DTL compared to the DSS group (Figure 4B). Additionally, in comparison to the DSS group, the level of TNF-\(\alpha\), a representative factor related to inflammation in UC, decreased by 20.7% in DTA, 62.9% in DLC, and 59.2% in DTL, with the DLC group  
Figure 3: Effects of phlorotannins (TAs) isolated from _E. bicyclis_ and _Lactobacillus casei_ (LC) in DSS-treated mice. (**A**) Body weight changes. (**B**) Histogram showing proportion of weight change. (**C**) DAI index. (**D**) Colon length of each group of mice on the day of sacrifice. (**E**) Quantification chart for colon length. (**F**) Spleen weight. (**G**) Chart quantifying histological scoring. (**H**) Representative images of colon tissues. Black arrows indicate crypt loss, while red arrows indicate inflammatory cell infiltrates. Mice were fed experimental extracts (50 mg/kg bw/day) or PBS via oral gavage for 30 days. Subsequently, from day 17 to day 24, 3% dextran sulfate sodium (DSS) was provided in the drinking water, and _Lactobacillus casei_ (1 \(\times\) 10\({}^{8}\) cells/100 \(\mu\)L) was administered from day 21 to day 28. All data are expressed as mean \(\pm\) SD (\(n\) = 8/group). * \(p\) \(<\) 0.05, **_p_ \(<\) 0.01, ***_p_ \(<\) 0.001, ***_p_ \(<\) 0.0001. One-way ANOVA followed by [PERSON]’s test. DSS: 3% DSS in drinking water for 7 days; DTA: DSS-Phlorotannin; DLC: DSS-_Lactobacillus casei_; DTL: DSS-Phlorotannin-_Lactobacillus casei_. exhibiting the most significant decrease (Figure 4C). However, no significant decrease in IL-6 levels was observed (Figure 4D). Effects of TA and LC on mRNA Expressions of Inflammatory Markers and Tight Junctions in DSS-Treated Mice  
To determine the mechanisms underlying the combined effects of TA and LC, we evaluated the genetic factors implicated in the development of inflammation. RNA was extracted from the mouse colon tissue to assess the mRNA expression of key inflammatory markers and tight junction genes. The measured inflammatory genetic factors included Nfkb, Cox2, and iNos mRNA, which are representative inflammatory markers. Compared with the DSS group, Nfkb exhibited a significant reduction in inflammation in all extract treatment groups, with the DTL group demonstrating the most substantial reduction (Figure 5A). Cox-2 mRNA showed the most significant reduction, notably by 37.9%, in the DTL group compared to the DSS group (Figure 5B). The expression of iNOS demonstrated a decrease of 43.1% in DTA, 35.2% in DLC, and 70.5% in DTL compared to the DSS group (Figure 5C). Moreover, tight junction genes (Mu2, Zo-1, Occludin, and Claudin1), crucial for protecting the epithelial barrier in inflammatory bowel disease, were assessed. The Muc2 gene increased by 29.3% in DTA and 64.2% in DTL, showing a significant improvement in tight junctions, specifically in the DTL group (Figure 5D). In comparison to the DSS group, all sample treatment groups exhibited an enhanced protective effect. Notably, the DTL group demonstrated a superior protective effect compared to the DTA and DLC groups, showing the highest significance in maintaining epithelial barrier integrity (Figure 5E-G). Figure 4: Effects of TA and LC on inflammatory cytokine levels in DSS-treated mice. (**A**) Lipocalin-2 in serum and (**B**) IFN-\(\gamma\), (**C**) TNF-\(\alpha\), and (**D**) IL-6 levels in colon tissue of mice were measured by ELISA assay. Mice were fed experimental extracts (50 mg/kg bw/day) or PBS via oral gavage for 30 days.