Crystallography, morphology, and thermal properties of starch in Fritillaria thunbergii and F. ussurensis as well as comparison with potato starch / 中草药

ABSTRACT

Objective To fully understand the medicinal plants of Fritillaria L. , the physicochemical properties of starch in two species of Fritillaria L. , F. thunbergii and F. ussurensis. were investigated by means of various analytical methods. Methods The properties of starch in the two different species of Fritillaria L. were compared by X-ray diffraction, scanning electron microscope (SEM) and themogravimetric analysis (TGA). Results The crystal type of starch in the two species of Fritillaria L.was the characteristic B-type which was in consistent with that of potato starch. The degrees of crystallinity of F. thunbergii starch and F. ussurensis starch were about 29.9% and 20.1%, respectively. However,the degree of crystallinity of the potato starch was 44.9%. From the crystallinity degree of the starch in two species of Fritillaria L. , it could be concluded that the content of amylose in F. ussurensis starch was higher than that in F. thunbergii starch. The granule size of the starch in two species of Fritillaria L.ranged from 5 to 40 μm, which were all smaller than that of the potato. The starch granule in two species of Fritillaria L. was in cycloidal or elliptic-shape. It could be concluded that the thermal stability of the starch in two species of Fritillaria L. was different due to the different structures of different starch in various plants by TGA. Conclusion The physicochemical properties of starch in two different species of Fritillaria L. differ a lot due to their geographical origin.