Simultaneous HPTLC analysis of flavonoids in the leaves of three different species of bamboo

Flavonoids are the main functional compounds in a bamboo leaf extract. Because of their activity flavonoids are widely used in many of health products, cosmetics, and food supplements. A simple high-performance thin-layer chromatographic (HPTLC) method has been established for simultaneous quantification of vitexin, isovitexin, orientin, and isoorientin in the leaves of three different bamboo species: Phyllostachys pubescens Mazel ex H. de Lehaie, Phyllostachys glauca McClure, and Pleioblastus yixingensis S. L. Chen et S. Y. Chen. The method was validated for precision (expressed as the coefficient of variation, CV [%]), accuracy, sensitivity, and selectivity. Instrumental precision was found to be 0.37, 0.52, 0.39, 0.13, and 0.84% and the repeatability of the method 0.98, 0.91, 1.02, 1.04 and 0.87% for isovitexin, rutin, orientin, isoorientin, and vitexin, respectively. The accuracy of the method was determined by measurement of recovery at three different concentrations. Average recovery was 99.54% for isovitexin, 99.31% for orientin, and 100.55% for isoorientin from P. pubescens; 98.97% for orientin, 99.00% for isovitexin, and 99.58% for vitexin from P. glauca ; and 98.86% for orientin, 100.04% for isoorientin, and 99.63% for vitexin in P. yixingensis . In the fraction extracted from bamboo leaves known as Flavone Gruff the flavonoid content was 6.44% ( w/w ) for orientin, 3.45% for isovitexin, and 6.58% for isoorientin in P. pubescens ; 7.82% for orientin, 2.82% for isovitexin, and 13.7% for vitexin in P. glauca ; and 4.92% for orientin, 3.50% for isoorientin, and 22.5% for vitexin in P. yixingensis . Although the presence of rutin was confirmed in the bamboo leaves investigated, it could not be quantified because of its low concentration. The proposed HPTLC method was found to be simple, precise, selective, sensitive, and accurate for routine quality control of the leaves of different bamboo species and formulations containing bamboo-leaf flavonoids.