Screening And Application Of Monascus Pigments With Anti-inflammatory Activity

Monascus pigment is a secondary metabolite produced by monascus fermentation.Many studies have shown that monascus pigment has functional activities such as lowering blood lipid,anti-allergy,anti-diabetes,anti-oxidation,maintaining vascular homeostasis,alleviating insulin resistance and non-alcoholic steatohepatitis.In this study,seven monascus pigments R1,R2,O1,O2,MC,MS and AK were extracted and purified in the laboratory,and the pigments with anti-inflammatory effect were evaluated by LPS-induced RAW264.7 cell inflammatory model to provide theoretical basis for application of monascus pigments in anti-inflammatory medicine and health food.The main methods and results are as follows:Firstly,the safe concentration range of seven pigments was determined by MTT assay,and RAW264.7 cells were treated with LPS as an in vitro inflammatory model,it was found that LPS concentration of 2 μg/m L had the best inflammatory effect.Then RAW264.7 cell inflammatory model was treated with different pigments within the safe concentration range,and it was found that R1,R2,MC,MS and AK could obviously inhibit NO production.The same plate cells were used to evaluated again,and the anti-inflammatory effect of MC,MS and AK was significant(p< 0.01),and the effect was not different from that of positive control dexamethasone(p> 0.05),but the survival rate of MS decreased significantly(p< 0.01).The results of cell scratch test showed that MC and MS had a good ability to inhibit the migration of macrophages to the inflammatory site.RNA-Seq analysis showed that LPS upregulated several gene expressions and significantly upregulated genes in Toll-Like receptor signaling pathway,at the same time,the inflammation-related genes were significantly down-regulated with 6 μg/m L MC,which were mainly related to JAK-STAT signaling pathway.Among them,the expression level of IL6 family gene IL11 was changed most obviously.RNA-Seq analysis was further verified by RT-q PCR and ELISA.The results showed that the expression of IL6 and IL11 were significantly reduced by three yellow pigments(p < 0.01),and the cytokines IL6 and IL11 were also inhibit at a statistical level(p < 0.01).All the above indicated that MC has effective anti-inflammatory effect,which can provide basis for the development of functional food.In addition,making jelly drops with red yeast rice containing yellow pigments could have a variety of biological activities.