Characterization of a nontoxic pyomelanin pigment produced by the yeast Yarrowia lipolytica

Abstract

In this study, we report on the ability of the yeast Yarrowia lipolytica W29 to produce an extracellular melanin‐like brown pigment at high yield (0.5 mg/ml) in culture medium supplemented with L‐tyrosine. This pigment has been characterized as pyomelanin and its synthesis was found to occur by the so‐called HGA‐melanin pathway. The purified pyomelanin was found embedded with antioxidant properties as it exhibited a radical scavenging activity toward 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) with IC50 of 230 μg/ml. It was also characterized as noncytotoxic toward two mammalian cell lines, namely the mouse fibroblast NIH3T3 and human keratinocytes HaCaT. When blended with different commercial sunscreens, the purified pyomelanin increased significantly the sun protection factor (SPF) value, highlighting its potential utilization as UV‐filter in cosmetic preparations.

Occurrence of Yeasts in White-Brined Cheeses: Methodologies for Identification, Spoilage Potential and Good Manufacturing Practices

“…Recently, Ben Tahar et al (2020) verified production of melanin pigments in Y. lipolytica W29 via L-tyrosine catabolism. Interestingly, these pigments exhibited both antioxidant and antimicrobial activities, indicating perspectives for biotechnological applications of Y. lipolytica (Ben Tahar et al, 2020).…”

“…In this connection, bio-protective cultures offer a promising alternative to chemical preservatives (Crowley et al, 2013). Bio-protective cultures are referred as food cultures, deliberately applied as live microorganisms to control the microbiological status in food (EFFCA, 2018;Ben Said et al, 2019). As food additives, bio-protective cultures should have "generally recognized as safe" (GRAS) status and be included in the qualified presumption of safety (QPS) list in Europe (Ben Said et al, 2019).…”

“…Bio-protective cultures are referred as food cultures, deliberately applied as live microorganisms to control the microbiological status in food (EFFCA, 2018;Ben Said et al, 2019). As food additives, bio-protective cultures should have "generally recognized as safe" (GRAS) status and be included in the qualified presumption of safety (QPS) list in Europe (Ben Said et al, 2019). In addition to yeast inhibition, bio-protective cultures should be able to proliferate in dairy products without affecting the performance of other starter and adjunct cultures, and without changing the technological and sensory quality of the products (Schnürer and Magnusson, 2005).…”

“…On the opposite, the increased content of glucose correlated with a delay of browning in tyrosine-containing laboratory medium ( Carreira et al, 2001a , b ). The brown pigments, known as melanins, are produced by yeasts from L-tyrosine via dihydroxyphenylalanine (DOPA) pathway or through accumulation and autoxidation of a pigment precursor, homogentisic acid (HGA) ( Carreira et al, 2001b ; Schmaler-Ripcke et al, 2009 ; Ben Tahar et al, 2020 ). In Y. lipolytica , production of pigments includes synthesis and accumulation of HGA, followed by convertion of HGA into benzoquinone acetic acid by autoxidation, which is further turned into pyomelanin through self-polymerization ( Figure 2 ) ( Ben Tahar et al, 2020 ).…”

“…The brown pigments, known as melanins, are produced by yeasts from L-tyrosine via dihydroxyphenylalanine (DOPA) pathway or through accumulation and autoxidation of a pigment precursor, homogentisic acid (HGA) ( Carreira et al, 2001b ; Schmaler-Ripcke et al, 2009 ; Ben Tahar et al, 2020 ). In Y. lipolytica , production of pigments includes synthesis and accumulation of HGA, followed by convertion of HGA into benzoquinone acetic acid by autoxidation, which is further turned into pyomelanin through self-polymerization ( Figure 2 ) ( Ben Tahar et al, 2020 ). Recently, Ben Tahar et al (2020) verified production of melanin pigments in Y. lipolytica W29 via L-tyrosine catabolism.…”