Methods: Chemical profiling of P. blanda was carried out using gas chromatography mass spectrometry (GCMS) followed by isolation of bioactive compounds by column chromatography. DPPH• and FRAP assays were used to evaluate antioxidant activity and the MTT assay was performed to estimate the cytotoxicity activity against three cancer cell lines, namely MCF-7, HL-60 and WEHI-3, and three normal cell lines, MCF10A, WRL-68 and HDFa.
Results: X-ray crystallographic data for peperomin A is reported for the first time here and N,N'-diphenethyloxamide was isolated for the first time from Peperomia blanda. Methanol and dichloromethane extracts showed high radical scavenging activity with an IC50 of 36.81 ± 0.09 µg/mL, followed by the dichloromethane extract at 61.78 ± 0.02 µg/mL, whereas the weak ferric reducing activity of P. blanda extracts ranging from 162.2 ± 0.80 to 381.5 ± 1.31 µg/mL were recorded. In addition, petroleum ether crude extract exhibited the highest cytotoxic activity against all the tested cancer cell lines with IC50 values of 9.54 ± 0.30, 4.30 ± 0.90 and 5.39 ± 0.34 µg/mL, respectively. Peperomin A and the isolated mixture of phytosterol (stigmasterol and β-sitosterol) exhibited cytotoxic activity against MCF-7 and WE-HI cell lines with an IC50 of (5.58 ± 0.47, 4.62 ± 0.03 µg/mL) and (8.94 ± 0.05, 9.84 ± 0.61 µg/mL), respectively, compared to a standard drug, taxol, that has IC50 values of 3.56 ± 0.34 and 1.90 ± 0.9 µg/mL, respectively.
Conclusion: The activities of P. blanda extracts and isolated compounds recorded in this study underlines the potential that makes this plant a valuable source for further study on anticancer and antioxidant activities.
PRACTICAL APPLICATION: The results of this study provide a better understanding on the stability of bioactive compounds and antioxidant activities in oil-in-water nanoemulsions that stabilized by similar ternary emulsifiers during storage at different temperatures. In addition, this study could be used as a predictive model to estimate the shelf life of bioactive compounds encapsulated in the form of nanoemulsions.
METHODS AND RESULTS: We performed a systematic search of all available RCTs conducted up to 21 February 2019 in the following databases: PubMed, Scopus, and Cochrane. The choice of fixed- or random-effect model for analysis was determined according to the I2 statistic. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence interval (CI). Pooling of 12 effect sizes from seven articles revealed a significant reduction of Lp(a) levels following PS supplementation (MD: -0.025 mg/dl, 95% CI: -0.045, -0.004, p = 0.017) without significant heterogeneity among the studies (I2 = 0.0%, p = 0.599). Also, PS supplementation significantly lowered FFA (MD: -0.138 mg/dl, 95% CI: -0.195, -0.081, p = 0.000) without significant heterogeneity among the studies (I2 = 0.0%, p = 0.911). The results for meta-regression and sensitivity analysis were not significant.
CONCLUSION: The meta-analysis suggests that oral PS supplementation could cause a significant reduction in serum Lp(a) and FFA.