Variability of macro and microelement content in pods and leaves of the carob tree (Ceratonia siliqua L.) in Croatia

The pods, seeds and leaves of the carob tree (Ceratonia siliqua L.) are widely used in the pharmaceutical industry, and especially in the food industry. In this study, the mineral content was investigated in carob pods and leaves in twelve Croatian carob populations. Macro and microelement contents, as highly important nutrients, were determined by inductively coupled plasma mass spectrometry (ICP-MS). Total ash content, determined by the gravimetric method, ranged from 2.30 to 2.97% in pods and from 4.95 to 7.90% in leaves. Among the macroelements, K content was highest in pods (9,020.09–11,208.97 mg/kg), while Ca was highest in leaves (11,059.67–22,756.81 mg/kg). Microelement contents ranged from 0.00 mg/kg (Cr) to 136.70 mg/kg (Na) in pods, and from 0.02 mg/kg (Cr) to 243.55 mg/kg (Na) in leaves. The results of the macro and microelement analyses were evaluated using multivariate analysis (PCA and UPGMA).