Cultural characteristics and extraction of the fungal pigment phleichrome from the phytopathogenic fungusCladosporium phlei

Characterization of a mutant strain of a filamentous fungus Cladosporium phlei for the mass production of the secondary metabolite phleichrome

“…In addition, the liquid culture of M0035 in V8 juice supplemented with 5% glucose and 2% malt extract yielded mycelial masses of 20.5 g/L after 15 days incubation, comparable to that of the wild-type strain, indicating no growth defects (Lee et al, 2007). However, when the conidial production of the M0035 on V8 juice agar plates was analyzed, a 1,000-fold reduction in the number of conidia per plate was observed regardless of the light exposure.…”

“…Numbers indicate sample preparations from the corresponding days after the incubation. Lane C in the TLC plate contains purified phleichrome from previous studies (Lee et al, 2007). stant low-level (<2,000 l x) light at 20°C and stored as frozen agar plugs harboring actively growing young hyphae in 5% DMSO solution at -70°C.…”

“…Briefly, 10 agar blocks of uniform size (0.5-cm-diameter) were excised from 0.5-cm behind margins of actively growing colonies and were gently agitated for 5 h in 2 ml of ethyl acetate (EtOAc) at 20°C (Smedsgaard, 1997). The samples were then centrifuged for 5 min at 5,000×g and the crude extract was analyzed using TLC with a resolving solution (CH2Cl2:MeOH=9:1, v/v) and a purified phleichrome as a control (Lee et al, 2007). As shown in Fig.…”

“…As pigmentation of the wild-type strain changed to a dark green color from the characteristic purple, we examined the phleichrome production according to the culture age using thin-layer chromatography (TLC) of the crude extract from the agar plugs, which contained actively growing mycelia (Lee et al, 2007). Briefly, 10 agar blocks of uniform size (0.5-cm-diameter) were excised from 0.5-cm behind margins of actively growing colonies and were gently agitated for 5 h in 2 ml of ethyl acetate (EtOAc) at 20°C (Smedsgaard, 1997).…”

“…Thus, as a preparation methodology for the sustainable production of phleichrome, the establishment of biological methodologies, including strain improvement and the optimization of the fermentation process, is considered as the best, probably the only, alternative option. Recently we reported the culture characteristics of C. phlei and the extraction of phleichrome, which resulted in 43 mg/L and 2 mg/L of phleichrome in mycelia and the culture filtrate, respectively (Lee et al, 2007). In addition, a fungal transformation system was recently established for the genetic manipulation of C. phlei (Kim et al, 2009).…”