Evaluation of Anti-Inflammatory Activity in Methanolic Seed Extracts of International Sorghum bicolor L. Resources

Abstract

Sorghum is an important cereal with high value as a health food ingredient because it contains various phenolic compounds. Anti-inflammatory activity was assessed using 12 sorghum resources collected from various countries to explore their potential as medicinal resources. The findings revealed that, at extract concentrations of 25 µg/mL and 50 µg/mL, cell survival rates were observed to be between 70 and 80% for most varieties, with the exception of K159081. In the analysis of anti-inflammatory activity, measured by the rate of nitric oxide (NO) production, sorghum varieties K159041 and K159081 exhibited NO production rates of 0.46 ± 0.38% and 2.58 ± 0.20%, respectively, indicating significant anti-inflammatory properties. The investigation into anti-inflammatory effects also included examining the expression of the inducible nitric oxide synthase (iNOS) gene, which is related to the inflammatory response triggered by LPS in macrophages. Varieties K159041, K159048, K159077, K159078, K159081, K159089, and K159096 were analyzed for this purpose. Further, an expression test of the cyclooxygenase 2 (COX-2) gene revealed values less than 0.4 in K159077, K159081, and K159089, suggesting these sorghum lines possess higher anti-inflammatory activity compared to others. Additionally, the expression analysis of tumor necrosis factor alpha (TNF-α), a gene identified as an inflammatory cytokine, showed that the mRNA levels in the lines K159048, K159077, K159078, K159088, K159089, K159093, and K159096 were expressed at lower levels relative to other sorghum resources, categorizing them as having high anti-inflammatory activity. Notably, the K159081 line exhibited the lowest expression level of all genes associated with inflammation, marking it as a valuable medicinal resource with potential development as an anti-inflammatory agent.