SCREENING OF Monascus purpureus STRAIN WITH MONACOLIN K ACTIVITY AND CITRININ-FREE CHARACTERISTICS FOR RED YEAST RICE PRODUCTION BY LC-MS/MS ANALYSIS BY LC-MS/MS ANALYSIS

Abstract

Red yeast rice is produced from rice using Monascus purpureus fungus, which results in the red colour of the fermented rice. Red yeast rice has been used for a thousand years as a food preservative and in traditional medicine to support vascular and digestive health. The compound known as monacolin K is the main active component that helps decrease blood cholesterol. However, the byproduct of fermentation is citrinin, which causes hepato-nephrotoxic mycotoxin. This study used Liquid Chromatography-Mass Spectrometry (LC-MS/MS) to concurrently analyse citrinin and monacolin K produced by M. purpureus strain. The pigmentations were varied when cultured on various media such as PDA, PGA, MGA, MCM, and SDAY media. MGA (61.12 – 1,996.20 AU/g) and PGA (8.78 – 507.26 AU/g) displayed the highest levels of red pigment, while SDAY (10.55– 31.79 AU/g) showed the lowest levels. Morphological examination revealed typical features of Monascus sp., including spherical or oval shapes and spore chains of two to four spores. Qualitative analysis of chromatographic plates TLC revealed consistent bands of Monacolin K standard across most strains, indicating their potential for producing this compound, with exceptions like strain BS3-GLTT. Notably, strains C3.12, C5.17, C4.1, C1.15, and BS3-GLTT exhibited either faint or absent spots corresponding to citrinin, suggesting their potential as citrinin-free strains. Furthermore, the C5.17 strain identified as Monascus purpureus, under specific conditions, yielded a monacolin K concentration of 292,32 ppm, with no detectable citrinin by LC-MS/MS analysis, highlighting its suitability for monacolin K production.