Antidiabetic Potential and Chemical Profiling of Chloroform Fraction from Euclea racemosa subsp. schimperi In Vitro

Background: The chloroform fraction (CHCl3 Fr.) of Euclea racemosa subsp. schimperi has enormous interest for its potential therapeutic properties in managing diabetes and oxidative stress-related conditions. This study aimed to evaluate the chemical composition and biological activities of CHCl3 Fr. through LC-ESI-MS/MS and GC-MS analyses. Methods: The CHCl3 Fr. was analyzed using LC-ESI-MS/MS for identification of bioactive compounds, and its inhibitory effects on α-amylase and α-glucosidase were assessed in vitro. Additionally, the impact on insulin secretion, C-peptide levels, and oxidative stress markers (MDA and NO) were measured. Results: Nineteen bioactive compounds, including flavonoids, pentacyclic triterpenes, and monounsaturated fatty acids, were identified in the chloroform fraction (CHCl3 Fr.). It significantly inhibited α-amylase and α-glucosidase, with IC50 values of 21.16 ± 2.13 and 13.49 ± 0.83 µg/ml, respectively. In insulin-resistant Huh7 cells, CHCl3 Fr. reduced glucose levels and increased insulin and C-peptide levels (p < 0.05). While it decreased malondialdehyde and nitric oxide, it did not significantly enhance catalase or total antioxidant capacity (p > 0.05). Compared to metformin, CHCl3 Fr. showed less efficacy but may improve insulin resistance and reduce oxidative stress, likely due to its bioactive compounds. Conclusion: The presence of diverse bioactive compounds contributes to the antidiabetic effects of CHCl3 Fr. from E. r. ssp. shimperi, showed its potential as a natural therapeutic agent for diabetes management and oxidative stress reduction. Further investigations are warranted to explore its clinical applications and underlying mechanisms.