Highlighting Protective Effect of Encapsulation on Yeast Cell Response to Dehydration Using Synchrotron Infrared Microspectroscopy at the Single-Cell Level

Abstract

In the present paper, the Layer by Layer (LbL) method using β-lactoglobulin and sodium alginate was performed to individually encapsulate Saccharomyces cerevisiae cells in microorganized shells in order to protect them against stresses during dehydration. Higher survival (∼1 log) for encapsulated yeast cells was effectively observed after air dehydration at 45°C. For the first time, the potentiality of Synchrotron-Fourier Transform InfraRed microspectroscopy (S-FTIR) was used at the single-cell level in order to analyze the contribution of the biochemical composition of non-encapsulated vs. encapsulated cells in response to dehydration. The microspectroscopy measurements clearly differentiated between non-encapsulated and encapsulated yeast cells in the amide band region. In the spectral region specific to lipids, the S-FTIR results indicated probably the decrease in membrane fluidity of yeast after dehydration without significant distinction between the two samples. These data suggested minor apparent chemical changes in cell attributable to the LbL system upon dehydration. More insights are expected regarding the lower mortality among encapsulated cells. Indeed the hypothesis that the biopolymeric layers could induce less damage in cell by affecting the transfer kinetics during dehydration-rehydration cycle, should be verified in further work.

Pulsed Electric Field (PEF) Enhances Iron Uptake by the Yeast Saccharomyces cerevisiae

“…The ATR-FTIR spectra of lyophilized yeast cells stained from the control sample (C1), the iron-enriched samples both without PEF treatment (C2) and with the use of PEF at optimal conditions (Fe + PEF) were recorded in the region between 4000 and 750 cm −1 . The location of the characteristic bands corresponds to the data reported in the literature [40][41][42][43][44], (Figure S1, Table S1).…”

Diffraction-limited mid-infrared microspectroscopy to reveal a micron-thick interfacial water layer signature

“…Infrared microspectroscopy down to the diffraction limit has been widely applied to study biological samples in the past 40 years. It allowed exploring individual cells for revealing the damage mechanisms and modification of protein structure, 2,3 diagnosing diseases, [4][5][6][7][8] studying microbiology and bacteria, [9][10][11][12][13] biochemical and bio-physical modification processes, [14][15][16][17][18][19] and variation of chemical composition. [20][21][22][23] In all that, working at the diffraction limit was crucial to downscale at the size of the individual biological object.…”

Hydrogen Bonding‐Based Layer‐by‐Layer Assembly of Nature‐Derived Eggshell Membrane Hydrolysates and Coffee Melanoidins in Single‐Cell Nanoencapsulation

“…Tsukruk, Kaplan et al. used silk fibroin and its derivatives for the SCNE of microbial and mammalian cells, [22–25] and the LbL pairs of alginate/chitosan, [26,27] alginate/gelatin, [28] alginate/β‐lactoglobulin, [29,30] and alginate/starch [31] also have been used for SCNE. In addition to the LbL‐SCNE, Sakai et al.…”

“…[19,20] For example, Akashi, Matsusaki et al reported a layer-by-layer (LbL)-SCNE approach to the construction of three-dimensional, multilayered tissues with gelatin and fibronectin as LbL building blocks. [21] Tsukruk, Kaplan et al used silk fibroin and its derivatives for the SCNE of microbial and mammalian cells, [22][23][24][25] and the LbL pairs of alginate/ chitosan, [26,27] alginate/gelatin, [28] alginate/β-lactoglobulin, [29,30] and alginate/starch [31] also have been used for SCNE. In addition to the LbL-SCNE, Sakai et al constructed the hydrogel sheaths through the horseradish peroxidase-catalyzed oxidative coupling of phenolic moieties made present in biopolymers (e. g., alginate and gelatin).…”