How does the pH level affect the growth and lipid production in yeast?
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The pH level significantly influences the growth and lipid production in yeast. Research indicates that slightly acidic conditions are commonly favored for oleaginous yeast cultivation, but an acidic pH exacerbates the inhibitory effect of volatile fatty acids (VFAs) due to their undissociated form . In contrast, maintaining a pH of 6 optimizes cell growth and lipid accumulation in Yarrowia lipolytica, enhancing lipid content and dry cell weight . Controlling pH in Y. lipolytica cultures boosts lipid and citric acid production, showing a 15% increase compared to uncontrolled pH conditions . Moreover, maintaining a pH of 6 in Y. lipolytica cultures optimizes cell growth rate, intracellular lipid accumulation, and reduces foaming, highlighting the importance of pH regulation for efficient lipid production . Additionally, Lipomyces starkeyi growth is inhibited at pH 5 but thrives at pH 6, with co-consumption of xylose and acetic acid enhancing lipid production in fed-batch cultures .
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| Papers (5) | Insight |
|---|---|
50 Citations | pH significantly impacts growth and lipid production in Lipomyces starkeyi; growth halted at pH 5 with 10% hydrolysate, while pH-regulated fed-batch cultures enhanced lipid production from hemicellulose. |
10 Citations | At pH 6, Yarrowia lipolytica shows optimized growth rate, lipid accumulation, and reduced foaming in multiphasic bioreactors, highlighting the significant impact of pH on yeast physiology and bioprocess efficiency. |
| In Trichosporon cutaneum, pH 6.0-7.0 induces unicellular yeast cells with higher lipid content and dry cell weight compared to acidic conditions, enhancing lipid production through up-regulation of key metabolic pathways. | |
29 Citations | Controlling pH enhances lipid production by 15% in Yarrowia lipolytica SKY7, with no significant impact on biomass, showing a direct correlation between growth and lipid production. |
| Alkaline conditions (pH 8) alleviate inhibitory effects of high-content volatile fatty acids on Yarrowia lipolytica, enhancing biomass and lipid production significantly compared to acidic conditions. |
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