Department of Biology and Pharmaceutical Botany, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Łódź.
Department of Cosmetic Raw Materials Chemistry, Faculty of Pharmacy, Medical University of Lodz, Muszyńskiego 1, 90-151 Łódź.
Biomolecules. 2020 Sep 29;10(10):1391. doi: 10.3390/biom10101391.
The study examines the phenolic compounds in hydromethanolic extracts of (L.) leaves and bark as well as their antioxidant activity and cytotoxic potential. UPLC-PDA-Q/TOF-MS analysis showed a total of 29 phenolic compounds in leaves and 34 in bark. Total phenolic compound content was 5575.96 mg/100 g of dry weight (DW) in leaves and 2330.31 mg/100 g DW in bark. The compounds were identified as derivatives of phenolic acids (seven in leaves and five in bark), flavanols and procyanidins (eight in leaves and 26 in bark) and flavonols (14 in leaves and three in bark). Both extracts exhibited strong antioxidant potential, assessed by radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS), but the bark extract was even stronger than the ascorbic acid used as a standard. The cytotoxicity of both extracts was evaluated against human skin fibroblasts and human epidermal keratinocytes cell lines using the Presto Blue cell viability assay. The keratinocytes were more resistant to tested extracts than fibroblasts. The leaf and bark extracts at concentrations which exhibited antioxidant activity were also not toxic against the keratinocyte cell line. Thus, extracts, especially the leaf extract, offer promise as a nontoxic natural antioxidant, in cosmetic products or herbal medicines, and as a source of bioactive secondary metabolites.
本研究考察了水甲醇提取物中（L.）叶和树皮中的酚类化合物及其抗氧化活性和细胞毒性。UPLC-PDA-Q/TOF-MS 分析表明，叶中有 29 种酚类化合物，树皮中有 34 种。叶中总酚含量为 5575.96mg/100g 干重（DW），树皮中为 2330.31mg/100g DW。这些化合物被鉴定为酚酸（叶中 7 种，树皮中 5 种）、黄烷醇和原花青素（叶中 8 种，树皮中 26 种）和类黄酮（叶中 14 种，树皮中 3 种）的衍生物。两种提取物均表现出较强的抗氧化潜力，通过对 1,1-二苯基-2-苦基肼（DPPH）和 2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸（ABTS）的自由基清除活性进行评估。然而，与用作标准品的抗坏血酸相比，树皮提取物甚至更强。通过 Presto Blue 细胞活力测定法，对两种提取物对人皮肤成纤维细胞和人表皮角质形成细胞系的细胞毒性进行了评估。与成纤维细胞相比，角蛋白细胞系对测试提取物的抗性更强。在表现出抗氧化活性的浓度下，叶和树皮提取物对角蛋白细胞系也没有毒性。因此，提取物，特别是叶提取物，有望成为一种无毒的天然抗氧化剂，用于化妆品或草药药物，并作为生物活性次生代谢物的来源。
