绞股蓝提取液对蛋白核小球藻的化感效应及影响机理研究

以中草药植物绞股蓝Gynostemma pentaphyllum(Thunb.) Makino]为化感供体材料,研究其不同浓度的提取液(0、5、10、25、50 g/L)对蛋白核小球藻(Chlorella pyrenoidesa)生长及生理生化特征的化感效应。结果表明:(1)绞股蓝提取液对蛋白核小球藻生长均具有抑制作用,其抑制作用随提取液质量浓度增大和培养时间延长均呈增强趋势,且25 g/L绞股蓝提取液培养15 d时的抑制率达到最大(79.41%)。(2)各浓度绞股蓝处理组蛋白核小球藻细胞内的叶绿素a含量均低于对照组,且随着提取液浓度升高以及处理时间延长叶绿素a含量较对照的降低量越多,表明蛋白核小球藻光合作用受到的影响也越大。(3)绞股蓝处理组蛋白核小球藻细胞的膜透性(吸光度OD_(264))显著高于对照,且膜透性随着提取液浓度增大而增强;高浓度提取液处理下,藻细胞内部的可溶性蛋白质(OD_(280))及核酸(OD_(260))含量均显著高于对照,且随着处理时间延长,细胞膜透性增大,细胞内部的可溶性蛋白质及核酸向胞外渗透增多。研究发现,绞股蓝提取液能够抑制蛋白核小球藻生长,并随着提取液质量浓度增大而增强;绞股蓝提取液能促进藻细胞叶绿素分解、增加细胞膜透性,引起可溶性蛋白质和核酸向胞外渗透量升高,导致藻细胞结构受损,代谢功能紊乱,从而达到化感抑制作用。

Allelopathic Effect and Mechanism of Gynostemma pentaphyllum (Thunb.) Makino Extract on Chlorella pyrenoidesa

The growth and physiology of Chlorella pyrenoidesa were studied by using different concentrations of G. pentaphyllum extract (0, 5, 10, 25, 50 g/L). The results showed that: (1) G. pentaphyllum extract could inhibit the growth of C. pyrenoidesa, with the increasing concentration and the prolonging time of cultivate, the inhibition increased. And the inhibition rate reached the maximum that was 79.41% when C. pyrenoidesa was cultured for 15 days with 25 g/L of G. pentaphyllum extract. (2) Chlorophyll a content in the cells of each concentration treatment group was lower than that of control group. With the increase of extraction concentration and the extension of treatment time, chlorophyll a content decreased more than that of control group. This result indicated that the photosynthetic effect of C. pyrenoidesa was affected. (3) The cell membrane permeability (absorbance OD₂₆₄) of the treatment groups was significantly higher than that of control group, which meant the cell membrane permeability increased with the increase of the concentration of the extract. At high concentration, both OD₂₆₀ and OD₂₈₀ were significantly higher than that of control group. And the cell membrane permeability was increased with the extension time, and more soluble proteins and nucleic acid were infiltrate out of the cells. The experimental results indicated that inhibition was enhanced with the increase of the concentration, and its mechanism of action was to promote chlorophyll decomposition and increase cell membrane permeability as well as promote soluble protein and nucleic acid exosmosis. So the structure of algal cells damaged and metabolic disorders happened, thus allelopathic inhibition was achieved.