Authors:R. S. Bedi, V. K. Gauttam, and A. N. Kalia
A simple, selective, precise, and reproducible high-performance thin-layer chromatography (HPTLC) method for the analysis of vicine in herbal extracts and formulations containing Momordica charantia was developed. The study was performed on aluminum-based pre-coated TLC plates (silica gel 60F254). The chromatograms of samples were developed in twin trough glass chamber pre-saturated with mobile phase comprised of ethyl acetate-methanol-water-formic acid (7.5:3:1:0.1, v/v/v/v) at room temperature (25 ± 2°C). The densitometric analysis was carried out in absorbance mode at 278 nm. The optimized mobile phase showed a compact spot of vicine (RF = 0.31 ± 0.02) from the other constituents present in the samples. The linear regression analysis data for the calibration plots showed good linearity (r2 = 0.9990) with respect to peak area in the range of 200–1400 ng spot−1. The method was validated as per International Conference on Harmonization (ICH) guidelines. The limits of detection and quantification (50 and 150 ng spot−1, respectively) were also established. The proposed method has shown the excellent recovery (98.01–99.33%), which supports the suitability of the method for the analysis. Statistical analysis of the obtained data showed the selectivity of the proposed method for vicine estimation in the herbal samples.
The study demonstrated that cultivation of Pleurotus ostreatus var. florida, Pleurotus eryngii, Pleurotus cornucopiae and Pleurotus djamor on selenium enriched substrate did not significantly affect biological efficiency (%), but total soluble protein content, total phenolic content, flavonoid content and free radical scavenging activity (%) were found to be significantly improved in Se enriched fruit bodies as compared to the control. Elemental analysis of the Se biofortified Pleurotus mushrooms through SEM-EDS showed signals characteristic for selenium on surface of P. ostreatus. var. florida and P. djamor confirming that selenium was incorporated into the cell wall of these fruiting bodies. The Se content was found to be 22.34 μg g−1 dw in Se enriched wheat straw and 0.059 μg g−1 dw in respective non-enriched wheat straw. Se contents of Se-enriched fruit bodies were found to be higher compared to non-enriched Pleurotus spp. FT-IR spectra of proteins from Pleurotus spp. indicated an increase in the flexibility, unfolding, hydrophilicity of the proteins upon Se supplementation.