Enrichment of dimerumic acid in Monascus‐fermented rice and its in vivo antioxidant activity

Abstract

Monascus-fermented rice (MFR) has been used in traditional Chinese and Japanese medicine for the revitalization of blood, digestion problems, and cardiovascular disorders. Through a biotechnological approach, MFR is produced by the solid-state fermentation of rice by Monascus spp. MFR has remarkable therapeutic properties as it contains several bioactive compounds, and dimerumic acid is one of the important siderophore-based antioxidant fermentative metabolites found in it. This study aimed to screen out the medium composition for the production of dimerumic acid (DMA) and evaluate its antioxidant potential. Different strains of Monascus purpureus Microbial Type Culture Collection & Gene Bank (MTCC) 410, 369, 1090 and Monascus ruber MTCC 1880, 2326 and Monascus pilosus CBS 286.34, CBS 290.34 with different solid substrate were screened for maximum yield of DMA. Solid-state fermentation of longgrain rice (Oryza sativa) by Monascus pilosus CBS 290.34 was the best for DMA production. The optimized medium parameters in rice for the highest yield of DMA were glucose (75.13 mg/g), soya extract (19.33 mg/g), malt extract (35.14 mg/g), and calcium carbonate (0.29 mg/g). The predicted values for medium parameters were in good agreement with the experimental data. MFR enriched with DMA showed potent antioxidant and lipid lowering capacity in both in vitro and in vivo. It can be explored further for the development of nutraceuticals as a natural antioxidant.

Guideline for screening antioxidant against lipid‐peroxidation by spectrophotometer

“…Adding BHT into the system can improve the results (Tsikas, 2017). Although with the disadvantage of nonspecificity, it is still considered the gold standard for the determination of LPO for its simplicity as well as low cost, and is widely used in antioxidant screening (Félix et al, 2020; Khan et al, 2021; Oyeniran et al, 2021; Shrivastava et al, 2021).…”

Recent advances in dietary androgen receptor inhibitors

“…Both as azaphilone derivatives from the ethanol extract of red yeast rice fermented by Monascus pilosus BCRC 38093, 245,246 monascin and monascinol antagonized androgen-stimulated PSA promoter activity with IC 50 values of 67.5 and 7.0 µM, respectively, suggesting that they might serve as nonsteroidal AR antagonists. 124 In addition to the above natural antiandrogens, a series of other natural products have also been identified as potential AR inhibitors through virtual screening, 247,248 and the biological validation of their antiandrogenic activity needs to be performed before further clinical development.…”

Synthetic biology for Monascus: From strain breeding to industrial production

“…And the production of DMA in red yeast rice is primarily determined by the expression levels of siderophore biosynthesis genes ( sidF , sidH , sidI , and sidD ) and transporter genes ( mirB , mirC ). [ 151 ] The fermentation metabolism of Monascus can also produce GABA. The strategy to improve GABA yield mainly lies in fermentation optimization, [ 152 ] and there are few studies on the modifications of its synthetic pathway.…”