From Strain to Substance: A Novel Approach to Red Yeast Rice Quality Assessment and Chromatographic Fingerprinting

Red yeast rice has notable lipid-lowering efficacy, but strain diversity among Monascus sources complicates quality evaluation. To address this issue, a systematic analytical framework integrating morphological and molecular identification of Monascus strains, quantitative detection of key bioactive components, and chromatographic fingerprinting was established. Five Monascus species were identified by morphology and ITS sequencing. Quantitative analysis revealed wide concentration ranges for acid Monacolin K (0.15–23.29 mg/g), lactone Monacolin K (0.03–14.22 mg/g), ergosterol (0.94–22.79 mg/g), guanosine (10.35–852.19 μg/g), adenosine (0.06–147.96 μg/g), γ-aminobutyric acid (2.76–1217.43 μg/g), and β-glucan (0.08–4.73 mg/g). HPLC fingerprinting established eight characteristic common peaks with similarity coefficients above 0.802, and fingerprint-based analysis revealed considerable differences in bioactive component contents among species: M. sanguineus and M. ruber had the lowest levels, M. fumeus and M. fuliginosus the highest, and M. purpureus intermediate. This multi-dimensional framework integrating strain identification and component quantification provides a reliable tool for comprehensive quality assessment of red yeast rice.