Models of estimation on the content of secondary metabolites in some Hypericum species

Abstract

In the present study, models for estimation of the content of main secondary metabolites, namely hypericin, pseudohypericin and hyperforin were developed for Hypericum originafolium Willd, Hypericum perfoliatum L. and Hypericum montbretii Spach. growing in Northern Turkey. Wild growing plants were harvested at vegetative, floral budding, full flowering, fresh fruiting, mature fruiting stages and dissected into stem, leaf and reproductive tissues. Actual secondary metabolite contents of plant materials were measured by High Performance Liquid Chromatography method. Multiple regression analysis with Excel 2003 computer package program was performed for each species and chemicals separately to develop multiple regression models. The produced equation for predicting the content of secondary metabolites in different tissues of the species was formulized as: SMC= [a + (b1 x S) + (b2 x L) + (b3 x RP) + (b4 x S²) + (b5 x (1/RP))] where SMC is whole plant secondary metabolite content, S is stem secondary metabolite content, L is leaf secondary metabolite content, RP is secondary metabolite content of reproductive parts and a, b1, b2, b3, b4, and b5 are coefficients?. The R2 coefficient values between predicted and observed contents of secondary metabolites were determined as 0.99 for H. originafolium, 0.95–0.98 for H. perfoliatum and 0.90–0.99 for H. montbretii. All R² values and standard errors were found to be significant at the P<0.05 level.