响应面试验优化脆江蓠多糖提取工艺及其对肿瘤细胞的抑制作用

目的：研究脆江蓠多糖（Gracilaria chouae polysaccharides，GLP）的提取方法及其对肿瘤细胞生长的影响。方法：响应面法优化GLP提取工艺条件；四甲基偶氮唑蓝（methyl thiazolyl tetrazolium，MTT）法检测GLP对体外培养的人宫颈癌（HeLa）、食道癌（EC-109）、肝癌（HepG-2）以及乳腺癌（MCF-7）细胞生长的影响。结果：GLP最佳提取条件为预热温度93.1 ℃、料液比1∶61.5（g/mL）、超声时间35 min，在此条件下GLP提取率为16.75%。GLP在质量浓度200～1 000 μg/mL范围内对实验细胞均有抑制作用，且呈剂量依赖关系。当GLP质量浓度为1 000 μg/mL时，其对HeLa、HepG-2、MCF-7和EC-109细胞的抑制率分别为49.11%、41.18%、34.98%和31.33%。对HeLa细胞形态学观察以及Annexin V-FITC/PI荧光染色检测发现，随着GLP给药剂量的增加，凋亡和坏死细胞不断增多。结论：GLP对体外培养的人HeLa、EC-109、HepG-2以及MCF-7等癌细胞增殖有抑制作用，并能诱导肿瘤细胞凋亡。

Optimization of Extraction of Polysaccharides from Gracilaria chouae and Their Inhibitory Effects on Tumor Cells

Objective: To optimize the extraction of polysaccharides from Gracilaria chouae (GLP) and to investigate their
inhibitory effects on tumor cells. Methods: Response surface methodology was used to optimize the extraction process for GLP.
Methyl thiazolyl tetrazolium (MTT) method was used to determine the effects of GLP on the proliferation of HeLa, EC-109,
HepG-2 and MCF-7 cells. Results: The optimal extraction conditions were determined as follows: temperature, 93.1 ℃;
material-to-liquid ratio, 1:61.5 (g/mL); and ultrasonification time, 35 min. Under these conditions, the maximum yield of
polysaccharides of 16.75% was obtained. GLP revealed anti-proliferation effect on HeLa, EC-109, HepG-2 and MCF-7 cells
in a dose-dependent manner in the range of 200–1 000 μg/mL. When the concentration was up to 1 000 μg/mL, the percentage
growth inhibition of the above four cells were 49.11%, 41.18%, 34.98% and 31.33% respectively. With increasing GLP dose
over a certain range, the numbers of apoptotic and necrotic cells increased, as revealed by cell morphology observation and
Annexin V-FITC/PI fluorescence double staining detection. Conclusions: GLP could induce apoptosis of cancer cells.