Abstract

Many biological activities have been reported for the Ilex genus. However, few studies in the literature have reported on guayusa. To address this gap in our knowledge, chemical analysis of guayusa leaves was made. Extracts were obtained by applying Soxhlet, maceration, supercritical CO₂ and pressurised liquid extraction techniques, using water and ethanol as solvent/cosolvent. Extracts were evaluated for their phenolic content and antioxidant capacity. The chemical profile was obtained from HPLC. In raw guayusa leaves were identified caffeine (2.27 ± 0.05%), protein (15.31 ± 0.07%) and lipids (11.81 ± 0.14%). Extracts presented the highest phenolic content (156.56 ± 1.32 mg GAE g⁻¹) and the best antioxidant activity (EC₅₀= 61.85 ± 0.21 µg mL⁻¹) when water was used as solvent/cosolvent. Through HPLC, three main substances were determined and quantified in the extracts: caffeine, theobromine and 5-caffeoylquinic acid. Based on these results, guayusa may be considered a natural source of compounds with potential application in the food and pharmaceutical industries.

摘要

已报道冬青属的许多生物活性。然而，文献中很少有关于guayusa的研究。为了弥补我们知识上的这一空白，对番石榴叶进行了化学分析。_{通过应用索氏提取、浸渍、超临界CO 2}和加压液体提取技术，使用水和乙醇作为溶剂/共溶剂获得提取物。评估了提取物的酚含量和抗氧化能力。从 HPLC 获得化学特征。在生番石榴叶中鉴定出咖啡因 (2.27 ± 0.05%)、蛋白质 (15.31 ± 0.07%) 和脂质 (11.81 ± 0.14%)。当水用作溶剂/共溶剂时，提取物呈现出最高的酚含量（156.56 ± 1.32 mg GAE g ⁻¹）和最佳的抗氧化活性（EC ₅₀ = 61.85 ± 0.21 µg mL ^{−1 ）。}通过 HPLC，对提取物中的三种主要物质进行了测定和定量：咖啡因、可可碱和 5-咖啡酰奎尼酸。基于这些结果，番石榴可能被认为是一种在食品和制药行业具有潜在应用潜力的化合物的天然来源。