Fig 1.
Morphological appearance of Chlorella sorokiniana UTEX 1230 grown in monosaccharide-supplemented medium.
Photos of C. sorokiniana UTEX 1230 cultivated for 7 days in medium supplemented with different concentrations of monosaccharides. Left (black bar) and right (white bar) panels show flasks cultured under dark and light conditions, respectively. The photos were taken with a digital camera against a white background.
Fig 2.
Pigment contents of Chlorella. sorokiniana UTEX 1230 grown in monosaccharides-supplemented mediums.
The contents of DMSO extracted pigment from C. sorokiniana UTEX 1230 were determined by the optical density under corresponding wavelength. The line graph was drawn, x- and y-axes on the graph correspond to monosaccharide concentration and pigment contents, respectively. The left panel (black bar) showed the pigment extracted from cultures under dark condition. The right panel (blank bar) showed the pigment extracted from cultures under light condition. Data shown as mean +/-SD, n = 3. ChlA: chlorophyll a; ChlB: chlorophyll b; Carot: total carotenoid.
Fig 3.
Cell density alterations to Chlorella sorokiniana UTEX 1230 grown in monosaccharide-supplemented medium.
The density of C. sorokiniana UTEX 1230 cells collected after 7 days culture in monosaccharide-supplemented medium were determined by spectrophotometry at 750 nm. a, b, c, and d show cell densities following culture in glucose-, fructose-, galactose- and xylose-supplemented media, respectively. Data shown as mean +/-SD, n = 3. Black bar: dark conditions; white bar: light conditions.
Fig 4.
Biomass analysis of Chlorella sorokiniana UTEX 1230 in monosaccharide-supplemented medium.
C. sorokiniana UTEX 1230 cells were collected after 7 days and dried to a constant weight at 80 °C to weigh biomass. X- and y-axes on the graph correspond to monosaccharide concentration and biomass (g/L), respectively. a, b, c and d show the biomass of cells cultivated in glucose-, fructose-, galactose- and xylose-supplemented media, respectively. Data shown as mean +/-SD, n = 3. Black bar: dark conditions; white bar: light conditions.
Fig 5.
Lipid yield of Chlorella sorokiniana UTEX 1230 in monosaccharide-supplemented medium.
Lipid yield of C. sorokiniana UTEX 1230 cells collected from monosaccharide-supplemented medium after 7 days culture was determined by the sulfo-phospho-vanillin method. Lipid yield per mL of culture was calculated. X- and y-axes on the graph correspond to monosaccharide concentration and lipid yield (μg/mL), respectively. a, b, c and d show the lipid yield of cells cultivated in glucose-, fructose-, galactose- and xylose-supplemented media, respectively. Data shown as mean +/-SD, n = 3. Black bar: dark conditions; white bar: light conditions.
Fig 6.
Residual monosaccharide after 7 days cultivation of Chlorella sorokiniana UTEX 1230.
Residual monosaccharides (final concentration at 7 days) as measured by the dinitrosalicylic acid method and calculated based on a standard curve. a, b, c and d show remaining monosaccharide from glucose-, fructose-, galactose- and xylose-supplemented media, respectively. Data shown as mean +/-SD, n = 3. Black bar: dark conditions; white bar: light conditions.
Fig 7.
Relative protein abundances of Chlorella sorokiniana UTEX 1230 cells cultivated in glucose-supplemented medium.
C. sorokiniana UTEX 1230 cells cultured in glucose-supplemented medium were harvested. Extracted total protein was separated by SDS-PAGE (10%) and stained with Coomassie brilliant blue (a). Arrows designated the bands with changed intensity at different glucose concentration. Signal intensities were extracted by ImageJ software, and showed as relative protein abundance per unit culture volume (b). Relative protein abundance per unit dry weight (c) was calculated by dividing with the amount of biomass. Data shown as mean +/-SD, n = 3. Black bar: dark conditions; white bar: light conditions.