| Porcine lung contains a lot of nutrients, including protein, fat, calcium, phosphorus, iron, niacin, vitamin B1, vitamin B2 and so on. Currently, most lungs directly sold or processed that lead additional value is considerable low. Therefore, exploitation lung is not only increasing raw material resources for food, medicine and other industries and effectively reduce slaughterhouse waste pollution of the surrounding ecological environment, but also can improve the comprehensive utilization rate of the porcine lung and with good economic and social benefits. In this paper, porcine lung was used as the materials to extract heparin sodium, antioxidant peptides and proteins. The physicochemical properties of them were determined and analyzed. The main research contents and results are as follows:(1) Extraction, separation and purification of heparin sodium. With the hexuronic acid extraction rate as index, the optimal conditions were obtained by response surface methodology (RSM) based on single-factor. The optimum extraction temperature was 53℃, the extraction time was 4 h, and the pH value was 8.5. Under these conditions, the hexuronic acid extraction rate was 5.49%. The extraction yield of crude product was 0.81% and the potency was 6.5 U/mg. The heparin sodium with high purity was obtained after removal of proteins, ethanol precipitation and purified by chromatography. At this time, the extraction yield of purified product was 0.05% and potency was 108.3 U/mg.(2) The physical-chemical properties of heparin sodium. The agarose gel electrophoresis showed that the purified and standard product had same migration distance and spots. An IR spectrum showed the characteristic absorption peaks were 890 cm’1 and 940 cm-1, UV spectrum displayed the maximum absorption wavelength was 207.5 nm meanwhile there were not absorption wavelength at 260 nm and 280 nm In 1H-NMR, the 1H of acetyl glucosamine appeared at δ=5.53; the 1H of sulfated iduronic acid arised at δ=5.19; the 5H of GlcNs6s showed at δ=4.93; the 4H of GlcNS6S emerged at δ=3.61; the 1H of N-sulfated glucosamine taken at 5=3.30; the methyl of N-acetyl glucosamine discovered at δ=2.05. In 13C-NMR, the C-2 of GlcNs6s found at δ=57.95; the C-2 of IdoA2s observed at δ=75.74; the C-6 of carbonyl in IdoA2s surveyed at δ=174.65.(3) Extraction, separation and purification of antioxidant peptide. On the basis of single-factor experiment, the optimization of technological condition was obtained by RSM with the DPPH radical scavenging activity as index. The optimum extraction conditions as follows:Solid-liquid ratio was 1:3, extraction time was 6 h and enzyme concentration was 6500 U/g. Meanwhile, the DPPH radical scavenging was 66.89%, and the extraction yield of rude antioxidant peptide was 9.78%. After the separation and purification of dextran gel Sephadex G-50, G-25 and G-10, receiving the most active antioxidant component C5, its extraction rate was 1.29%. Finally, by liquid chromatography mass spectrometry (LC-MS) measured the molecular weight of C5 was 452.00 Da.(4) The physical-chemical properties of antioxidant peptides. The UV spectrum displayed the maximum absorption wavelength was 224 nm. Scanning electron microscopy indicated that C5 had smooth surface and in the shape of lump. An IR spectra showed that the bending vibration of the carboxyl at 1402 cm-1, the presence of an amine at 3427 cm-1, the inner surface of the bending vibration of the hydroxyl group at 1405 cm-1, the signal of a carbonyl at 1640 cm-1. The EC50 of the DPPH radical scavenging, superoxide anion radical scavenging activity, ABTS radical scavenging, and hydroxyl radical scavenging activity were 0.073 mg/mL,0.989 mg/mL,0.192 mg/mL and 1.261 mg/mL, respectively.(5) Extraction and characterization of proteins. With the extraction rate of protein as index, the optimal conditions were received by RSM based on single-factor. The optimum extraction conditions were as follows:Solid-liquid ratio was 1:3, extraction time was 1.5 h, and pH value was 9.7. Meanwhile, the extraction rate of protein was 8.28%. The UV spectrum demonstrated the maximum absorption wavelength was 279 nm. Amino acid automatic analyzer discovered there were 18 amino acids including glutamate, leucine, aspartate, arginine, and valine and so on. Among these amino acid, leucine and valine amino acids were not synthesized by body. The synchronous thermal analyzer illustrated protein began to degrade at 200℃ and the degradation ended at 600℃, showing their better thermal stability. Scanning electron microscopy displayed that protein had smooth surface and in the shape of linear. |
PDF Full Text Request