The effect of the addition of weak acids into CO 2 -loaded solvents or rich solvents on the energy requirement of CO 2 desorption was investigated experimentally. The commercially available CO 2 solvent monoethanolamine (MEA) was used to absorb different amounts of CO 2 . Subsequently, a few weak acids such as suberic acid, phthalic acid, and oxalic acid were added into the solvents to study the effect of acid amount on the rate of CO 2 release. It was found that CO 2 could be released much faster and in much larger quantity with the addition of weak acids while the other desorption conditions were maintained the same. The amount of CO 2 released was found to be proportional to the amount of acid added. Acid addition could be potentially used to reduce the energy requirement for CO 2 desorption from solvent.

Late embryogenesis abundant (LEA) proteins are essential to the ability of resurrection plants and orthodox seeds to protect the subcellular milieu against irreversible damage associated with desiccation. In this work, we investigated the structure and function of six LEA proteins expressed during desiccation in the monocot resurrection species Xerophyta schlechteri (XsLEAs). In silico analyses suggested that XsLEAs are hydrophilic proteins with variable intrinsically disordered protein (IDP) properties. Circular dichroism (CD) analysis indicated that these proteins are mostly unstructured in water but acquire secondary structure in hydrophobic solution, suggesting that structural dynamics may play a role in their function in the subcellular environment. The protective property of XsLEAs was demonstrated by their ability to preserve the activity of the enzyme lactate dehydrogenase (LDH) against desiccation, heat and oxidative stress, as well as growth of Escherichia coli upon exposure to osmotic and salt stress. Subcellular localization analysis indicated that XsLEA recombinant proteins are differentially distributed in the cytoplasm, membranes and nucleus of Nicotiana benthamiana leaves. Interestingly, a LEA_1 family protein (XsLEA1-8), showing the highest disorder-to-order propensity and protective ability in vitro and in vivo, was also able to enhance salt and drought stress tolerance in Arabidopsis thaliana. Together, our results suggest that the structural plasticity of XsLEAs is essential for their protective activity to avoid damage of various subcellular components caused by water deficit stress. XsLEA1-8 constitutes a potential model protein for engineering structural stability in vitro and improvement of water-deficit stress tolerance in plants.