Enhancement of plant growth stimulation activity of irradiated alginate by fractionation

照射アルギン酸の分画による植物生長刺激活性の増大

Luan, L. Q.*; 長澤 尚胤; Ha, V. T. T.*; Hien, N. Q.*; 中西 友子*

Luan, L. Q.*; Nagasawa, Naotsugu; Ha, V. T. T.*; Hien, N. Q.*; Nakanishi, Tomoko*

海洋多糖類であるアルギン酸の線照射した分解生成物が植物生長促進効果を有しているが、その最適な分子量範囲,濃度を見いだすために、分画を行いムギ及びダイズの生長促進効果を検討した。200kGy照射して平均分子量が約1万4千に低下したアルギン酸は、約100ppmの濃度でムギとダイズに対して成長促進効果を与えた。その分解生成物を分画すると、分子量範囲1,000から3,000のアルギン酸が20ppmの低濃度で最も成長促進効果が高いことがわかった。

Alginate with the weight-average molecular weight () approximately 900 kDa and ratio of M (mannuronate)/G (guluronate) about 1.3 was irradiated by Co-60 in aqueous solution at doses up to 200 kGy. The irradiation dose was shown to be a function for reducing and molecular weight distribution of irradiated alginates. The distribution of oligomer fractions in irradiated products was also investigated by separation using ultrafiltration membranes. The irradiated alginate with approximately 14.2 kDa was found to have a positive influence for growing of barley and soybean. The irradiated oligoalginate fraction with ranging from 1 to 3 kDa displayed the strongest effect on the growth and development of the mentioned plants at low concentration (20 ppm). It is suggested that oligoalginate with in the range 1-3 kDa is a trigger for the growth and development of plants.