ABSTRACT
The binding of rhaponticin to bovine serum albumin (BSA)-bovine lactoferrin (BLF) and the factors that affect BSA-BLF interaction have been studied by fluorescence spectroscopy and Fourier transform infrared spectroscopy. In the fluorescence experiment, RT quenched the fluorescence intensity of mixed proteome and the maximum emission wavelength of BSA, BLF and BSA-BLF proteins system. RT caused obvious red-shift fluorescence for an interaction between RT and proteome. The interaction between RT and proteome was impacted by single-component protein molecular interactions and the interaction between RT-BSA and RT-BLF, the microenvironment of solutions were the factors impacting the interactions between RT and proteome, which impacted quantitative expression of the general environment micro environmental factors. In the Fourier transform infrared spectroscopy, the secondary conformation of protein molecules of single component in the protein group were changed, and the difference of the molecules' structure was responsible for the differences in the molecular conformation changes. The molecules' interaction in the single-component protein affected secondary conformation of the proteins' molecule. The proteins' concentration ratio and the interaction were different in degree of molecular conformational change. These data demonstrates an example of combination of fluorescence spectrum experiment with Fourier transform infrared spectroscopy in the study of protein structura.
ABSTRACT
Objective To evaluate the effects and mechanisms of bovine lactoferrin(bLF)on cell viability,proliferation,and the protective roles in intestinal epithelial cell-6(IEC-6)treated by lipopolysaccharide(LPS).Methods The rat jejunum epithelial cell lines IEC-6 were cultured in vitro.The effects of bLF on cell viability and proliferation in IEC-6 cells were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide(MTT)assay and 5-Bromo-deoxyuridine(Brdu)assay,respectively.Inflammatory cytokines and their mRNA of interleukin-1β(IL-1β),interleukin-6(IL-6),tumor necrosis factor-α(TNF-α)and interleukin-8(IL-8)were analyzed by real-time PCR and enzyme-linked immunosorbent assay(ELISA).Western blot was used to measure the levels of mitogen-activated protein kinase(MAPK)activation and nuclear factor kappa β(NF-κB)nuclear translocation.Results Dose dependent effects of bLF on cell viability and proliferation were observed in IEC-6 cells in vitro(F=3.825,5.861,all P<0.05),especially in a dose of 100 mg/L,and bLF significantly stimulated cell viability and proliferation compared with non-treatment group(q=5.240,3.765,all P<0.05).The mRNA levels of IL-1β,IL-6 and TNF-α were decreased by co-stimulation of bLF and LPS compared with the LPS treatments alone in IEC-6 cells in vitro(q=14.28,10.12,16.45,all P<0.001).The secretion of IL-6 and TNF-α was also decreased by co-stimulation of bLF and LPS(q=15.06,6.74,all P<0.01).In vitro,bLF treatment at dose of 100 mg/L could inhibit the activation of MAPK/NF-κB signal pathway induced by LPS(q=12.96,18.54,all P<0.001).Conclusion In vitro,bLF can promote IEC-6 viability and proliferation,and have anti-inflammatory effects via inhibited activation of MAPK/NF-κB nuclear translocation.
ABSTRACT
OBJECTIVE:To study the stability of Bovine Lactoferrin.METHODS:The content of Bovine Lactoferrin and its hybridprotein were determined by RP-HPLC.The stability of the samples was tested by high-light exposure,accelerating experiment and room temperature storage observation method.RESULTS:The linear range for Bovine Lactoferrin was25～ 1000?g/ml,RSD=0.05%.Under the high-light exposure experiment,accelerating experiment and room temperature storage observation,all the criteria were found to be in line with the quality standard specification.CONCLUSION:Stored under room temperature and airtight condition,Bovine Lactoferrin is stable in quality.