Study of Two Pools of Glycogen in Saccharomyces cerevisiae and their Role in Fermentation Performance

Abstract

Glycogen in Saccharomyces cerevisiae is present in two pools as cell wall bound and intracellular glycogen. The content of the cell wall bound glycogen was found to be almost three times higher than the intracellular glycogen. The content varied with the sugar concentration in the medium and an optimum value of 22.11 mg glycogen/g yeast was observed for the cell wall bound glycogen, while it was 7 mg/g yeast for the intracellular glycogen at a 12% medium sugar content. The two pools also varied with fermentation time reaching an optimal value at 36 h of fermentation. The cell wall bound glycogen was reduced by 85% during the first three hours after pitching, when sugar uptake was minimal and started to accumulate when almost 50% of the medium sugar was utilized. It was the cell wall bound glycogen that correlated with fermentation performance. Cells grown in 8% sugar content and rich in cell wall bound glycogen, when pitched into a 1% sugar medium showed an enhancement in ethanol content by 21%. The depletion of glycogen also affected fermentation performance.

Screening of Non- Saccharomyces cerevisiae Strains for Tolerance to Formic Acid in Bioethanol Fermentation

“…Accumulation of intracellular glycogen in yeast cells exposed to formic acid stress during fermentation was also determined. Higher accumulation of glycogen in yeast cells may act as an energy reserve maintaining cell viability when stressed [ 28 ]. Fig 7 revealed that increase in formic acid concentration decreased intracellular glycogen accumulation in all strains.…”

“…The intracellular glycogen may be playing a dual role according to Deshpande et al . [ 28 ], by providing energy and carbon skeleton required for cell growth as well as minimize leakage through plasma membrane by the stressful effect of formic acid. This agreed with Somani et al .…”

Structural differences on cell wall polysaccharides of brewer's spent Saccharomyces and microarray binding profiles with immune receptors

“…According to the linkage composition (Table 2), the solubilised material in hot water was similar in all species, composed mainly of t-Man, (2 → 6)-Man, and (1 → 2)-Man linkages, that together with the low content of total carbohydrates points to the presence of yeast mannoproteins (Coelho et al, 2011). The solubilised material in hot water was also composed of Glc-linkages, the most representative being the (1 → 4)-Glc, t-Glc and (1 → 4,6)-Glc (Table 2), suggesting the occurrence of soluble glycogen from cytosol (Deshpande et al, 2011). The main difference between the BSY from the two species is that the content of glucoselinkages in the solubilised material from S. cerevisiae was higher than that observed in the solubilised material from S. pastorianus, which in turn contains a higher content of mannose-linkages (Table 2).…”

The Improvement of Reserve Polysaccharide Glycogen Level and Other Quality Parameters of S. cerevisiae Brewing Dry Yeasts by Their Rehydration in Water, Treated with Low-Temperature, Low-Pressure Glow Plasma (LPGP)

“…The technology is mainly supported by data obtained in plant breeding, animal husbandry, cosmetology, medicine and food technology. Białopiotrowicz et al [15] treated water with LPGP in the presence of air (PTWAir), proving that the structure of the obtained water depends on the time of exposure (5,15,30,45,60 and 90 min) to plasma that changes nonlinearly. Other studies have described that PTWAir (plasma treated water under air atmosphere) stimulates various microorganisms [16], and promotes plant growth [17] and the healthy breeding of selected animals [18][19][20].…”