The study of the peptide composition of the supernatants from mealworm Tenebrio molitor larvae and goldfish Carassius auratus during cold acclimation

The molecular-mass distribution of peptides from supernatants, obtained from the tissues of larvae Tenebrio molitor and goldfish Carassius auratus during cold acclimation, has been determined by chromatography. The results showed that peptide spectrum of the supernatants from larvae T. molitor and C. auratus varied during cold acclimation. The supernatants from non-acclimated larvae of T. molitor and deacclimated fish possessed the highest number of peptide fractions. Furthermore, the cold-acclimated larvae of T. molitor had the peptide fractions of the low molecular weight (ca. 5.4⋅102 ÷22.6⋅102 Da), and non-acclimated insects had the peptides of the high molecular weight (ca. 46.8⋅102÷66⋅102 Da). Next, the organ-specific changes of the peptide composition of the goldfish during winter deacclimation have been revealed. Specifically, the low molecular weight peptides (ca. (14.1 ± 0.3)⋅102 and (6.75 ± 0.25)⋅102 Da), have been detected in the C. auratus muscles, and both the high (ca. (67.83 ± 0.21)⋅102 ( ca. 64.16 ± 0.26)⋅102 Da) and low (ca. (34.1 ± 1.0)⋅102 and (14.29 ± 0.15)⋅102 Da) molecular weight peptides have been detected in the liver. Quantitative and qualitative changes in the peptide spectra from supernatants of the T. molitor and C. auratus during cold acclimation could be one of the mechanisms of their natural adaptation to low temperatures.