Cancer is a serious health burden on global societies. The discovery and development of new anti-cancer therapies remains a challenging objective. Although it has been shown that lichen secondary metabolites may be potent sources for new anti-cancer agents, the Indonesian- grown folious lichens, Physcia millegrana, Parmelia dilatata and Parmeila aurulenta, have not yet been explored. In this study exhaustive preparative high-performance liquid chromatography was employed to isolate the lichen constituents with spectroscopic and spectrometric protocols identifying nine depsides 9–17, including the new methyl 4-formyl-2,3-dihydroxy-6-methylbenzoate 13. The cytotoxicity of the depsides towards cancer cells was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results indicated lowest toxicity of the depsides towards human A549 lung cancer cells. Importantly, the di-depsides (11, 12 and 17) showed greatest toxicity, indicating that these structures are biologically more active than the mono-depsides against the HepG2 liver cancer, A549 lung cancer and HL-60 leukemia cell lines.

中文翻译：

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从印度尼西亚多叶地衣中分离的 Depsides 的抗癌评价：Physcia millegrana、Parmelia dilatata 和 Parmelia aurulenta

癌症是全球社会的严重健康负担。新的抗癌疗法的发现和开发仍然是一个具有挑战性的目标。尽管已经表明地衣次生代谢物可能是新型抗癌剂的有效来源，但尚未对印度尼西亚生长的叶地衣Physcia millegrana、Parmelia dilatata和Parmeila aurulenta进行探索。在本研究中，采用详尽的制备型高效液相色谱分离地衣成分，并通过光谱和光谱分析方法鉴定了九种糖苷9 – 17，包括新的 4-甲酰基-2,3-二羟基-6-甲基苯甲酸甲酯13. 使用 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基溴化四唑 (MTT) 测定法评估 depsides 对癌细胞的细胞毒性。结果表明，depsides 对人 A549 肺癌细胞的毒性最低。重要的是，二缩酚酸（11，12和17）显示出最大的毒性，这表明这些结构是生物学不是对肝癌HepG2，人肺腺癌A549和HL-60白血病细胞系中的单缩酚酸更具活性。