Universidade do Estado da Bahia - UNEB, Departamento de Ciências Exatas e da Terra, Alagoinhas, BA, Brasil.
Universidade do Estado da Bahia - UNEB, Programa de Pós-graduação em Biodiversidade Vegetal - PPGBV, Senhor do Bonfim, BA, Brasil.
Braz J Biol. 2021 Jun 11;82:e242112. doi: 10.1590/1519-6984.242112. eCollection 2021.
Plants possess a renewable source of metabolites with enormous chemical structural diversity, which may have potential therapeutic relevance. Furthermore, this chemical diversity favors the possibility of finding new and different chemical constituents with antimicrobial, antioxidant and anti-tumor activities. This work analyzed preliminary phytochemical profiles and evaluated the antimicrobial, antioxidant and cytotoxic activities of hexane extracts of leaves of ten species of the family Melastomataceae. Phytochemical screening was performed using staining methods while total phenols and flavonoids were quantified by spectrophotometry. Antimicrobial activity was evaluated using the disk diffusion method. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazil (DPPH) method. Toxicity was recorded using the lethality test with Artemia salina Leach (1819). Cytotoxic activity of the extracts was assessed in vitro with acute monocytic leukemia cells (THP-1). Phytochemical analysis detected the presence of tannins, terpenes, steroids, polyphenols and flavonoids and the absence of alkaloids. Clidemia capitellata (Bonpl.) D. Don had the greatest amount of polyphenols (205.95 mg/g ± 4.14) while Clidemia hirta (L.) D. Don had the highest content of total flavonoids (143.99 mg/g ± 4.18). The hexane extracts did not show antimicrobial activity nor toxicity against Artemia salina. The extract of Tibouchina francavillana Cogn. was the most active in sequestering the DPPH radical. The extracts showed cytotoxicity in THP-1 cells with the appearance of apoptotic bodies and cell death. The extracts of Miconia amoena, Clidemia sericea and Clidemia capitellata are non-toxic against Artemia salina and induce the formation of apoptotic bodies and cell death of the THP-1 lineage.
植物具有丰富的代谢产物可再生资源，具有巨大的化学结构多样性，可能具有潜在的治疗相关性。此外，这种化学多样性有利于发现具有抗菌、抗氧化和抗肿瘤活性的新的和不同的化学成分。本工作分析了 10 种野牡丹科植物叶片的初步植物化学特征，并评价了其正己烷提取物的抗菌、抗氧化和细胞毒性活性。采用染色法进行植物化学筛选，采用分光光度法定量测定总酚和类黄酮。采用纸片扩散法评价抗菌活性。采用 2,2-二苯基-1-苦基肼（DPPH）法测定抗氧化活性。采用卤虫致死试验记录毒性。采用急性单核细胞白血病细胞（THP-1）体外法评估提取物的细胞毒性活性。植物化学分析检测到单宁、萜类、甾体、多酚和类黄酮的存在，以及生物碱的不存在。Clidemia capitellata（Bonpl.）D. Don 具有最高的多酚含量（205.95mg/g±4.14），而 Clidemia hirta（L.）D. Don 具有最高的总黄酮含量（143.99mg/g±4.18）。正己烷提取物对 Artemia salina 既没有抗菌活性，也没有毒性。Tibouchina francavillana Cogn. 的提取物对 DPPH 自由基的清除能力最强。提取物在 THP-1 细胞中表现出细胞毒性，出现凋亡小体和细胞死亡。Miconia amoena、Clidemia sericea 和 Clidemia capitellata 的提取物对 Artemia salina 无毒，诱导凋亡小体的形成，并导致 THP-1 系细胞死亡。
