Corncob hydrolysate, an efficient substrate for Monascus pigment production through submerged fermentation

Abstract

Monascus pigment has traditionally been produced by the fermentation of Monascus using rice powder or glucose as a culture substrate. Submerged fermentation can produce stable Monascus pigment yield and control the accumulation of the by-product, citrinin, which can then be more easily removed. To reduce the cost of Monascus submerged fermentation, the feasibility of corncob hydrolysate as an alternative substrate was investigated. Results showed that, when compared with a conventional glucose medium, the corncob hydrolysate medium produced an equivalent pigment yield without stimulating citrinin accumulation. Furthermore, the corncob hydrolysate medium and cultivation conditions were optimized to enhance pigment production and decrease citrinin synthesis. When Monascus sp. was cultured under dark conditions in the presence of caprylic acid, pigment production was increased to 25.8 ± 0.8 UA500 /mL, which was higher than that achieved in a glucose medium (24.0 ± 0.9 UA500 /mL), and those obtained in previously reported Monascus submerged fermentations using the same yield unit; on the other hand, citrinin accumulation was decreased to 26.2 ± 1.9 µg/L, which was significantly lower than that generated in the glucose control (44.3 ± 2.2 µg/L) and in those previously reported fermentations. Thus, corncob hydrolysate was proved to be an efficient alternative substrate for Monascus pigment production through submerged fermentation, which showed significant advantages over a conventional glucose substrate.

Production of Melanin Pigment by Fungi and Its Biotechnological Applications

“…The fungi grown under red light have no effect, and green or yellow light resulted in worsening effect in all the fungi, thus postulating the existence of photoreceptors responsive to dark and light in all the fungi. In a similar study, [56] noted that the production of pigment by Monascus species also was favored when the fungus was grown in the dark.…”

Red pigment production by Monascus purpureus using sweet potato-based medium in submerged fermentation

“…Studies on red pigment production by submerged fermentation is limited, but this method has many advantages over the solid-state process such as easy control of process parameters, high productivity, large volume processing, reduced fermentation time and cost [13]. Carbon and nitrogen sources constitute the major cost of the fermentation medium and several studies on alternate sources reported economical production of red pigment using various agroproducts and byproducts [14][15][16][17][18][19]. In our study, we used sweet potato powder as an alternate low-cost carbon source for red pigment production by submerged fermentation which has not been reported previously in the literature.…”

Soybean isoflavones reduce citrinin production by Monascus aurantiacus Li AS3.4384 in liquid state fermentation using different media

“…Lee and Lee found that the content of citrinin was obviously different with different culture medium and that the content of monacolin K was obviously increased during fermentation with Monascus using ganghwayakssuk as culture medium . Zhou et al found that citrinin was not present in corn hydrolysate medium used for fermentation with Monascus . Recently, some studies reported that mycotoxins were inhibited by polyphenol and flavonoid compounds.…”

“…34 Zhou et al found that citrinin was not present in corn hydrolysate medium used for fermentation with Monascus. 35 Recently, some studies reported that mycotoxins were inhibited by polyphenol and flavonoid compounds. Telles et al reported that chlorogenic and gallic acids had protective effects against the production of AFB 1 .…”