桑葉中の微量成分に関する研究

(第1報)桑葉中アルギニン配糖体の分離について

抄録

The authors found a new substance, argine-glucoside, in mulberry leaves. It was isolated from the fraction of an alcoholic basic lead acetate precipitation by the following treatment.
Dried mulberry leaves (1.45kg)
extract with 20l water
Residue Filtrate
add lead acetate
Filtrate ppt.
pH=8.0, NH₄OH₁
treat with basic lead acetate
Filtrate ppt.
condense in vaccuo.
treat with alcoholic basic lead acetate
ppt. Filtrate
H₂S
Pbs Filtrate
condense in vaccuo.
add alcohol
ppt. (1.8g)
developed by chromatopile
fraction: R_F 0.171_??_0.297
elute with (water)
White-powder (0.3g)
This substance is a white, hydroscopic powder giving a spot, its R_F value is 0.29 before hydrolysis, in paper-chromatography (developer; butanol: glacial acetic acid: water=4:1:2, the coloring agent is ninhydrin buthanol solution), and it gives spots pf glucose and arginine after hydrolysis. The authors supposed it to be arginine-glucoside, but it was very difficult to obtain a pure substance to analysis, so the authors tried to prove it by synthesis with glucose and arginine. This synthesized substance gives the same R_F value in paper-chromato-graphy as a natural substance before and after hydrolysis. And also, the percentage of nitrogen was in accordance with the theoretical percentage.
(N%: calcd. 16.7, found 16.85)
[α]^30.6_D=-0.4035°×100/0.5×10.793=-7.48 (water)
Then authors believe that the substance extracted from mulberry leaves is arginine-glucoside. The authors tried to obtain a crystalline acetylated substance, but could only get some unknown nitrogen-free substance. Perhaps, it might be decomposed by acetylation. The authors will report on this substance in latter papers.