# Production of Sustainable Postbiotics from Sugarcane Straw for Potential Food Applications
## 3 Results and Discussion
### Anti-Inflammatory Effect  
Interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-\(\alpha\)) are overexpressed in the intestine as a result of the inflammatory bowel disease, which is linked to immune system dysregulation [104]. The regulation of those biomarkers through diet could aid in disease prevention and be used as a co-adjuvant for disease treatment [105]. The possible inflammatory protective impact of sugarcane extract was evaluated using a pre-incubation of the Caco-2 cells media with extracts and a co-incubation (extract + IL-1 pro-inflammatory cytokine). The levels of three cytokines, IL-6, IL-8, and TNF-, were also assessed (Figure 7). The extract (3.125 mg/mL) was employed because it was the greatest dosage deemed physiologically safe for Caco-2 cells. IL-1 was used to provide the inflammatory stimulus. This cytokine is known to have a role in the beginning and amplification of inflammatory activity, which causes Caco-2 cells to produce biomarkers and inflammation mediators. [106]. In basal conditions, the presence of interleukins was not detected, and an amount of 11.4 pg/mL of TNF-\(\alpha\) was detected. The extract without stimulus was tested to verify if it has a pro-inflammatory effect, and cytokines quantities between 7 and 18 pg/mL were detected. After exposure to stimulus and with 3.125 mg/mL extract, a significant (\(p<0.05\)) decrease in IL-8 was detected from 876 to 806 pg/mL, compared to the positive control (challenge with IL-1\(\beta\)). IL-8 is a cytokine that promotes inflammation and is implicated in chemotaxis. Natural substances having the ability to block the synthesis of IL-8 are appealing because the expression of IL-8 by cancer cells enhances tumor angiogenesis, increases cancer cell proliferation and survival, and facilitates tumor escape from immune cells. Additionally, cancer patients' poor prognoses are linked to IL-8 expression by cancer cells [107]. The TNF-\(\alpha\) reduced from 65.7 to 54.4 pg/mL, corresponding to a decrease of 17%, while IL-6 increased from 55.0 to 142.6 pg/mL when compared with IL-1\(\beta\) stimulus. TNF-\(\alpha\) is produced by macrophages and is responsible to control the host immune response [108]. Meanwhile, IL-6 stimulates the differentiation or proliferation of several non-immune cells while also inducing an immunological response through the formation of effector T cells [109]. In this work, the fermented extract induced the production of IL-6 similarly to a work where a yeast-fermented Korean liquor by-product was tested which was mainly composed by polysaccharide fractions [110]. Monosaccharides showed  
Figure 7: Immunomodulatory effect on Caco-2 cell line after exposition to fermented sugarcane straw extract (0.625 mg/mL) with (SC+) and without _S. cerevisiae_ (SC-), using IL-1\(\beta\) as a pro-inflammatory stimulus. The concentration of interleukin-8 (IL-8), interleukin-6 (IL-6), and tumor necrosis factor (TNF-) (mean \(\pm\) SD) were measured. \({}^{\text{a,b,c,d}}\) Different letters indicate significant differences (\(p<0.05\)). immune-enhancing effects, and the activation of macrophages was dependent on the polysaccharides molecular weight [111]. Despite the fact that the exact processes by which polyphenols cause their anti-inflammatory effects are not entirely understood, it has been hypothesized that they do so by altering the synthesis of eicosanoids, blocking immune cells that have been activated, or by inhibiting nitric oxide synthase and xylooxygenase-2 through its inhibitory effects on nuclear factor NF-\(\kappa\)B [112; 113]. It was stated that fertile acid has a strong anti-inflammatory effect, and exerts protection action in the intestinal epithelial barrier dysfunction when stimulated with by LPS [114]. Some studies have discussed the potential of sugarcane polyphenols as anti-inflammatory agents. When Caco-2 cells were treated with IL-1B, a sugarcane stem aqueous extract (50 mol gallic acid equivalent/L) caused a 1.5-fold reduction in IL-8 release [115].