牛奶血清淀粉样蛋白A3含量与中红外光谱数据的关联性分析OA

To investigate the relationship between milk serum amyloid A3(SAA3)content and mid-infrared(MIR)spectral data,a total of 244 milk samples were collected.Milk SAA3 concentrations were quantified using enzyme-linked immunosorbent assay(ELISA),and transmission spectra were obtained in the 5 011-925 cm⁻¹ range at 1 060 wavenumbers using a CombiFoss FT+spectrometer.Data distribution was assessed using the Shapiro-Wilk test,and Spearman correlation analysis was performed to calculate the correlation coefficients between each spectral wavenumber and milk SAA3 content.The results showed that milk SAA3 concentrations ranged from 0.2 to 1.6 μg/mL,with an average of(0.65±0.21)μg/mL.The MIR spectrum was divided into five sub-regions based on spectral characteristics:short-wave infrared(SWIR,5 011-3 673 cm⁻¹),short-mid-wave infrared transition(SWIR-MWIR,3 669-3 052 cm⁻¹),mid-wave infrared 1(MWIR-1,3 048-1 701 cm⁻¹),mid-wave infrared 2(MWIR-2,1 698-1 586 cm ⁻¹),and mid-longwave infrared transition(MWIR-LWIR,1 582-925 cm ⁻¹).The SWIR-MWIR and MWIR-2 regions exhibited relatively high spectral variability.Correlation analysis revealed that 43 wavenumbers had relatively high correlations with milk SAA3 content,with absolute correlation coefficients greater than 0.1;among these,16 wavenumbers reached P<0.05,primarily distributed in the 3 155-3 148,1 562-1 539,and 1 466-1 446 cm⁻¹ regions,corresponding to N-H bond vibrations of proteins,amide II band absorption,and spectral features related to urea nitrogen and lipid metabolism,respectively.This study identified MIR spectral bands associated with milk SAA3 content,providing preliminary reference for selecting characteristic wavelengths for future quantitative prediction models based on machine learning.These findings also support the potential application of MIR spectroscopy in the clinical auxiliary diagnosis of bovine mastitis.