《Analysis of the differences in the chemical composition of monascus rice and highland barley monascus》

作者：Jia Chen,Qi Zheng,Zhenxing Zheng,Yirou Li, Hailang Liao, Hui Zhao, Dale Guo, and Yuntong Ma

ABSTRACT:

Monascus rice (MR) and highland barley monascus (HBM), the monascus fermented products, are applied in food and medicine to reduce cholesterol and promote digestion. Due to the fermentation substrates,their compositions are difffferent. However, the exact difffferences have not been reported to date. By UPLC-Q-Orbitrap HRMS analysis, multiple components of twenty batches of MR and HBM samples were identifified. In total, 100 components were confifirmed (e.g., monacolins, pigments, decalin derivatives,amino acids). Then, principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were used to fifilter the components of MR and HBM. In the PCA model, 88.1% of the total variance was uncovered. The OPLS-DA model showed better discrimination between MR and HBM,and the values of R2 X, R2 Y, and Q2 were 0.837, 0.996, and 0.956, respectively. Based on the value of the variable importance in projection (VIP) and the result of the t-test, 424 components (VIP > 1, p < 0.05) were acquired. Finally, 11 difffferential components were selected as the characteristic compounds to discriminate between MR and HBM: the content of 9 monacolins (3-hydroxy-3,5-dihydrodehydromonacolin K, monacolin K, dehydromonacolin K, dehydromonacolin J hydroxy acid, monacophenyl, dihydromonacolin J hydroxy acid, monacolin L, dehydromonacolin J, and monacolin R) in HBM was higher than the content in MR, but the content of 2 pigments (ankaflflavin and monascin) was lower in HBM and higher in MR. The fifindings revealed the similarities and difffferences in the chemical composition between MR and HBM, which is expected to provide a basis for quality control of HBM.

Experimental：

ankaflavin and luteolin were purchased from Naturewill Biotechnology Co., Ltd (Chengdu, China).