Fibroin, a fibrous protein found in silk
cocoon was extracted from Thai silkworms
(Bombyx mori L. var. Nangnoi Sisaket-1,
family Bombycidae). It is essential to
dissolve fibroin into solution prior to use.
Comparison of the protein pattern by
sodium dodecyl sulfate polyacrylamide gel
electrophoresis (SDS-PAGE) from 2
methods of fibroin solubilization between
lithium bromide (LiBr) to obtain FP-1
(fibroin powder from method 1) and the
tertiary system of CaCl2:EtOH:H2O (1:2:8
molar ratio) to obtain FP-1 (fibroin powder
from method 2) showed that the heavy
chain subunits of FP-1 was mostly degraded
whereas FP-2 giving clearly bands of 37 and
52 kDa. The difference of protein patterns
between FP-1 and FP-2 was also shown
from SDS-PAGE of the ammonium sulfate
precipitation. Under the inverted
microscope, the fibroin gel which was
formed by the SDS sample buffer was able
to bind to the color of aqueous extract from
Rosa spp petals. This binding capability of
fibroin gel suggests a complexation
between fibroin and anthocyanin. Thus, this
finding lead to further investigation for a
new method of anthocyanin stabilization.