Quantitative analysis of colony number in mouldy wheat based on near infrared spectroscopy combined with colorimetric sensor

摘要

Current work presented a novel method based on colorimetric sensor (CS) combined with visible/near-infrared spectroscopy (VNIRs) for the detection of volatile markers in wheat infected by Aspergillus glaucus. Wheat samples with different mouldy degree was cultivated for backup under temperature of 25?28 ?C in incubator. The total colony number was determined by flat colony counting method. Through employing chemo-responsive dyes including 8-(4-nitrophenyl)-4, 4-difluoro-BODIPY (NO2BDP), 8-(4-bromophenyl)-4,4-difluoro-BODIPY (BrBDP) and 8-phenyl-4,4-difluoro- BODIPY(HBDP) as capture probes of colorimetric sensor for volatile organic compounds (VOCs). The spectral data of CS-VNIRs were scanned and used to build synergic interval partial least squares (Si-PLS) models. The optimized Si-PLS model based on HBDP sensor gave a better detection performance, and the correlation coefficient of the prediction set Rp = 0.9387. The achieved high correlation rates imply that the technique may be deployed as a panacea to identify and quantify the colony number of different mouldy wheat.