Antioxidant Activity, Total Phenols and Carbohydrate and Mineral Concentrations of Pistacia lentiscus L. Sp. Pl. Portulace oleracea L. Sp. Pl. and Rubus sanctus Schreber. L con. Descr. Pl plants

Abstract

This study presents a comparative chemical evaluation of leaf and stem tissues from Pistacia lentiscus L. Sp. Pl., Portulaca oleracea L. Sp. Pl., and Rubus sanctus Schreber. L con. Descr. Pl., collected from multiple sites between the Al-Quba and Derna regions. The investigation focused on assessing antioxidant activity, total phenolic content, total carbohydrate levels, and the concentrations of selected mineral elements, namely sodium, potassium, and calcium. A combination of spectrophotometric techniques was employed to quantify antioxidant capacity, total phenols, and carbohydrates, while mineral analysis was performed using flame photometry. The results demonstrated that total phenolic content varied notably among samples, with concentrations ranging from 197.05 to 351.72 ppm. Antioxidant activity exhibited limited variation across the studied tissues, with values between 9.2 and 9.6 ppm in leaves and between 9.99 and 10.74 ppm in stems. Carbohydrate levels were consistently low in both leaves and stems across all investigated species, indicating that secondary metabolites rather than primary energy-storage compounds dominate the chemical composition of these plants. Mineral analysis revealed that calcium was present at lower concentrations compared to sodium and potassium. Potassium content showed marked variability, ranging from 6.36 to 77.16 ppm in leaves and from 52.36 to 84.36 ppm in stems, reflecting tissue-specific accumulation patterns and potential environmental influences. Overall, the findings highlight distinct differences in phytochemical and mineral profiles between plant organs and among species, underscoring the importance of tissue type and geographical origin in determining the chemical characteristics of medicinal plants.