Matrix-assisted Laser Desorption/ionization Time-of-flight Mass Spectrometry-Based Biotyping of Silk. II. Differences in 34 Local Silkworm Race Cocoons

Silk proteins and silk fibers from silkworm (Bombyx mori L.) cocoons were partially hydrolyzed by acids, and the cleaved peptide mass fragments (PMFs) were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Cleaved PMFs obtained via MALDI-TOF MS analysis were compared among 34 local silkworm race cocoons. Dendrograms were created based on the cleaved PMFs of raw, heat-treated, sodium carbonate-treated, Marseille soap-treated, and hydrogen peroxide-treated silk fibers against Marseille soap-treated silk fibers. The identified differences suggested that it was possible to distinguish between races of silkworm cocoons and fibers based on the cleaved PMFs.