Materials and methods

The strain used was Pichia sp. (strain #2) obtained from Cambrium (Berlin, Germany). A microbial suspension was prepared by growing Pichia sp.strain in tubes containing 10 mL of YPD (glucose) broth overnight at 27 °C for 24 h. Growth kinetics were studied using a YPD (glycerol version), basal salts fermentation media prepared with glucose and glycerol, citric acid prepared with glucose and glycerol, one per each treatment. Sterile 96-well flat-bottomed plates were filled with 250 µL per well. YPD (glucose version) was used as positive control. The microbial suspension was diluted to an initial absorbance of 0.05 at 600 nm (OD600). Growth kinetics were determined by monitoring OD600 at 27 °C for 21 h in a microplate reader (Biotek, Winooski, VT, USA).

Data <- readxl::read_xlsx("/Users/jessmontzam/Library/CloudStorage/OneDrive-Personal/Laboral/CENIBiot/Proyectos/2022/2022 Cambrium/20220129 Pichia preliminary results.xlsx", sheet = "R") 
Filtro <- c("YPD - S", "YPD - G", "Basal salts - S", "Basal salts - G", "Citric acid - S", "Citric acid - G")

DataFiltrada <- Data %>%
    filter(Sample %in% Filtro)

DataFiltrada$Sample <- factor(DataFiltrada$Sample, levels = Filtro)

Overlay <- ggplot(DataFiltrada, aes(x = Time, y = OD600, color = Sample)) +
  geom_point(size = 2.5) +
  geom_errorbar(alpha = 0.5, aes(ymin = OD600 - Error, ymax = OD600 + Error)) +
  labs(x = "Tiempo (h)", color = "Muestra")

Overlay 

Fwrap <- ggplot(DataFiltrada, aes(x = Time, y = OD600, color = Sample)) +
  geom_point(size = 2.5) +
  geom_errorbar(alpha = 0.5, aes(ymin = OD600 - Error, ymax = OD600 + Error)) +
  labs(x = "Tiempo (h)", color = "Muestra") +
  facet_wrap(~Sample)

Fwrap

Conclusion

According to the results shown, YPD and citric acid media are selected for optimization of the culture medium.