Salinity and Temperature Influence Growth and Pigment Production in the Marine-Derived Fungal Strain Talaromyces albobiverticillius 30548

Abstract

Marine-derived fungi that inhabit severe changing environments have gained increasing interest for their ability to produce structurally unique natural products. Fungi belonging to the Talaromyces and the close Penicillium genera are among the most promising microbes for bioactive compound production, including colored metabolites. Coupling pigment producing capability with bioactive effectiveness would be a valuable challenge in some specific fields such as dyeing, cosmeceutical, or food industries. In this sense, Talaromyces albobiverticillius 30548, a red pigment producing strain, has been isolated from the marine environment of Reunion Island, Indian Ocean. In this research, we analyzed the effect of temperatures (21–27 °C) and salinity levels (0–9%) on fungal growth and pigment production. Maximum pigment yield was obtained in non-salted media, when cultured at 27 °C after 10 days of submerged fermentation in PDB. However, maximum dry biomass production was achieved at stressed condition with 9% sea salts concentrated media at the same temperature. The results indicate that salinity of the culture media positively influences the growth of the biomass. Inversely, pigment production decreases with increase in salinity over 6%. Color coordinates of secreted pigments were expressed in CIELAB color system. The hue angles (h°) ranged from red to yellow colors. This indicated that the color distribution of fungal pigments depends on the salinity in the culture media. This study emphasizes the impact of abiotic stress (salt and temperature) on the growth and metabolome of marine-derived fungal strains.

Fungi as a Potential Source of Pigments: Harnessing Filamentous Fungi

“…Talaromyces albobiverticillius 30548, a red pigment producer strain was also isolated from sediment obtained from Reunion Island (Indian Ocean). Most of the compounds identified from this strain have been characterized as azaphilones (Venkatachalam et al, 2019). With the interest in both red and yellow hues for food colouration marine sediments are an area that could be targeted for the identification of further pigments.…”

Isolation, characterization and biotechnological potential of tropical culturable rhizospheric fungi from four mangrove species in Kenya

“…Initially, there were few reports about the occurrence of this genus in the mangrove ecosystems since it was classified under the genus Penicillium. But following its formal separation from the genus Penicillium, most researchers have detected this genus in mangrove ecosystems (Lima et al, 2018;Venkatachalam et al, 2019). Members of the genus Talaromyces form part of the major fungi adapted to the extreme conditions in mangrove ecosystems and have been reported to be a source of biotechnologically relevant bioactive molecules (Jie et al, 2016).…”

“…Interestingly, about 30% of the isolates were closely related to members of the genera Aspergillus and Penicillium [with >97% sequence identity]. Members from these genera are widely distributed including in the marine ecosystem (Zhou et al, 2018;Venkatachalam et al, 2019). For instance, isolate SAG35F1 [MT543129] had 100% similarity with Aspergillus terreus (MT279489), which was isolated from marine sediment in Vietnam, while isolate RMG15F2 [MT543115] had 98% sequence identity with Penicillium parvum (KF706683), which was recovered from deep sea sediment in China (Table 3).…”

“…The physiological analysis revealed that all the isolates were able to grow at different pH ranges (from low to high pH values [pH 4 to 12]), but some had growth preference for either slightly acidic or alkaline environment ( Figure 2a [MT543128]) grew at significantly lower NaCl concentrations (5 and 7%NaCl) compared to others, indicating difference in salinity levels preference. This is attributed to the pH fluctuations and high salinity levels in mangrove ecosystems (Venkatachalam et al (2019); thus, these fungal isolates are adapted to such conditions. A related study by Venkatachalam et al (2019) revealed that marine-derived genera Talaromyces and Penicillium, were the most promising for the production of compounds such as pigmented secondary metabolites, which can be applied in cosmeceutical or food industries.…”

“…This is attributed to the pH fluctuations and high salinity levels in mangrove ecosystems (Venkatachalam et al (2019); thus, these fungal isolates are adapted to such conditions. A related study by Venkatachalam et al (2019) revealed that marine-derived genera Talaromyces and Penicillium, were the most promising for the production of compounds such as pigmented secondary metabolites, which can be applied in cosmeceutical or food industries. These authors also observed that the production of the pigmented metabolites was regulated by the concentration of salt in the growth media.…”