Wang Yi-Ting, Yang Chih-Hui, Huang Ting-Yu, Tai Mi-Hsueh, Sie Ru-Han, Shaw Jei-Fu
Department of Biological Science and Technology, I-Shou University, Taiwan.
Pharmacy Department of E-Da Hospital, Taiwan.
Evid Based Complement Alternat Med. 2019 Jul 15;2019:9494328. doi: 10.1155/2019/9494328. eCollection 2019.
Chlorophyllide (chlide) is a natural catabolic product of chlorophyll (Chl), produced through the activity of chlorophyllase (chlase). The growth inhibitory and antioxidant effects of chlide from different plant leaf extracts have not been reported. The aim of this study is to demonstrate that chlide in crude extracts from leaves has the potential to exert cytotoxic effects on cancer cell lines. The potential inhibitory and antioxidant effects of chlide in crude extracts from 10 plant leaves on breast cancer cells (MCF7 and MDA-MB-231), hepatocellular carcinoma cells (Hep G2), colorectal adenocarcinoma cells (Caco2), and glioblastoma cells (U-118 MG) were studied using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and DPPH (1,1-diphenyl-2-picrylhydrazyl) assays. The results of the MTT assay showed that chlide in crude extracts from sweet potato were the most effective against all cancer cell lines tested. U-118 MG cells were the most sensitive, while Caco2 cells were the most resistant to the tested crude extracts. The cytotoxic effects of chlide and Chl in crude extracts from sweet potato and of commercial chlorophyllin (Cu-chlin), in descending order, were as follows: chlide > Chl > Cu-chlin. Notably, the IC of sweet potato in U-118 MG cells was 45.65 g/mL while those of Chl and Cu-chlin exceeded 200 g/mL. In the DPPH assay, low concentrations (100 g/mL) of chlide and Cu-chlin from crude extracts of sweet potato presented very similar radical scavenging activity to vitamin B2. The concentration of chlide was negatively correlated with DPPH activity. The current study was the first to demonstrate that chlide in crude extracts from leaves have potential cytotoxicity in cancer cell lines. Synergism between chlide and other compounds from leaf crude extracts may contribute to its cytotoxicity.
叶绿素酸酯（叶绿素ide）是叶绿素（Chl）的天然分解代谢产物，通过叶绿素酶（叶绿素酶）的活性产生。不同植物叶片提取物中叶绿素酸酯的生长抑制和抗氧化作用尚未见报道。本研究的目的是证明叶片粗提物中的叶绿素酸酯对癌细胞系具有潜在的细胞毒性作用。采用MTT（3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐）和DPPH（1,1-二苯基-2-苦基肼）法研究了10种植物叶片粗提物中叶绿素酸酯对乳腺癌细胞（MCF7和MDA-MB-231）、肝癌细胞（Hep G2）、结肠腺癌细胞（Caco2）和成胶质细胞瘤细胞（U-118 MG）的潜在抑制和抗氧化作用。MTT试验结果表明，红薯粗提物中的叶绿素酸酯对所有测试癌细胞系的效果最为显著。U-118 MG细胞最敏感，而Caco2细胞对测试的粗提物最具抗性。红薯粗提物中叶绿素酸酯和叶绿素以及商业叶绿酸铜（Cu-chlin）的细胞毒性作用由强到弱依次为：叶绿素酸酯>叶绿素>叶绿酸铜。值得注意的是，红薯粗提物在U-118 MG细胞中的半数抑制浓度（IC）为45.65μg/mL，而叶绿素和叶绿酸铜的IC超过200μg/mL。在DPPH试验中，红薯粗提物中低浓度（100μg/mL）的叶绿素酸酯和叶绿酸铜表现出与维生素B2非常相似的自由基清除活性。叶绿素酸酯的浓度与DPPH活性呈负相关。本研究首次证明叶片粗提物中的叶绿素酸酯对癌细胞系具有潜在的细胞毒性。叶绿素酸酯与叶片粗提物中其他化合物之间的协同作用可能有助于其细胞毒性。
