Zou Ping, Lu Xueli, Zhao Hongtao, Yuan Yuan, Meng Lei, Zhang Chengsheng, Li Yiqiang
Marine Agriculture Research Center, Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, China.
State Key Laboratory of Bioactive Seaweed Substances, Qingdao, China.
Front Plant Sci. 2019 Jan 31;10:48. doi: 10.3389/fpls.2019.00048. eCollection 2019.
Soil salinity reduces plant growth and is a major factor that causes decreased agricultural productivity worldwide. Seaweed polysaccharides promote crop growth and improve plant resistance to abiotic stress. In this study, polysaccharides from brown seaweed polysaccharides (LNP) were extracted and further separated and fractionated. Two acidic polysaccharides (LNP-1 and LNP-2) from crude LNP were obtained and characterized. The latter had a lower molecular weight (MW) (40.2 kDa) than the former (63.9 kDa), but had higher uronic acid and sulfate content. Crude LNP and LNP-2 were composed of mannose, glucuronic acid, fucose, and xylose, whereas LNP-1 has little mannose. Moreover, the effects of the three polysaccharides on plant salt tolerance were investigated. The results showed that crude LNP, LNP-1, and LNP-2 promoted the growth of plants, decreased membrane lipid peroxidation, increased the chlorophyll content, improved antioxidant activities, and coordinated the efflux and compartmentation of intracellular ion. All three polysaccharides could induce plant resistance to salt stress, but LNP-2 was more effective than the other two. The present study allowed to conclude that both MW and sulfate degree contribute to salt resistance capability of polysaccharides derived from .
土壤盐分降低植物生长，是导致全球农业生产力下降的主要因素。海藻多糖促进作物生长并提高植物对非生物胁迫的抗性。在本研究中，从褐藻中提取了多糖（LNP），并进一步进行分离和分级。从粗LNP中获得并表征了两种酸性多糖（LNP-1和LNP-2）。后者的分子量（MW）（40.2 kDa）低于前者（63.9 kDa），但糖醛酸和硫酸盐含量更高。粗LNP和LNP-2由甘露糖、葡萄糖醛酸、岩藻糖和木糖组成，而LNP-1几乎不含甘露糖。此外，研究了这三种多糖对植物耐盐性的影响。结果表明，粗LNP、LNP-1和LNP-2促进植物生长，降低膜脂过氧化，增加叶绿素含量，提高抗氧化活性，并协调细胞内离子的外流和区室化。所有三种多糖都能诱导植物对盐胁迫的抗性，但LNP-2比其他两种更有效。本研究得出结论，分子量和硫酸化程度均有助于褐藻来源多糖的抗盐能力。
