Comparative assessment of antioxidant capacity and phytochemical profiles of Tilia, Mentha and Salvia herbal teas

Herbal teas prepared from Tilia (linden), Mentha (mint), and Salvia (sage) species are widely consumed due to their potential health benefits and their traditional use in the management of respiratory disorders and cold-related symptoms. These plants contain various bioactive compounds, including phenolics, flavonoids, and carotenoids, which may contribute to their antioxidant properties. The present study aimed to comparatively evaluate the antioxidant potential and phytochemical composition of methanol and water extracts obtained from Tilia, Mentha and Salvia sp. The antioxidant activities of the extracts were assessed using DPPH radical scavenging activity, reducing power, and metal chelating activity assays. In addition, the levels of important bioactive compounds, including total phenolics, total flavonoids, β-carotene, and lycopene, were determined to investigate their relationship with antioxidant activity. The results revealed notable differences among the tested plant species and extraction solvents. The water extract of Salvia sp. exhibited the strongest DPPH radical scavenging activity (IC50: 0.157 mg/ml), while Mentha sp. extracts demonstrated the highest reducing power (EC50: 0.305 mg/ml) and metal chelating activity (IC50: 0.756 mg/ml). Phytochemical analyses showed that the methanol extract of Mentha sp. contained the highest β-carotene and lycopene levels, whereas the highest total phenolic content was detected in the water extract of Mentha sp. In contrast, Salvia sp. extracts, particularly the methanol extract, displayed the highest flavonoid content. These findings suggest that phenolic and flavonoid compounds play a major role in the antioxidant activity of the extracts, while carotenoids may further enhance their antioxidant potential. Overall, the findings highlight the importance of Tilia, Mentha, and Salvia sp. as natural sources of antioxidant compounds. Among the tested plants, Mentha and Salvia extracts demonstrated comparatively stronger antioxidant properties, indicating their potential value as functional ingredients in nutraceuticals and herbal beverages.