## 3 Results
### Catalytic Activity
Figure 6: Glucose (**A**) and levulinic acid (**B**) yields after the hydrolysis of the original barley straw and barley straw solids obtained (Solid I and Solid II) after treatment with ISH. Figure 7: Glucose (**A**) and levulinic acid (**B**) yields after the hydrolysis of the original pruning waste and pruning waste solids obtained (Solid I and Solid II) after treatment with ISH. Glucose production depended on the cellulose contents in the solid used in the reaction, and similar yields from solids with different starting cellulose contents implied that there were different glucose concentrations in the reaction media (see Figures S7, S9, and S11 in the Supplementary Information). The amount of glucose produced from Solid II was higher than that obtained from other samples. In summary, in all studied biomasses, an improvement in the reactivity in hydrolysis reactions was observed by obtaining glucose and levulinic acid when treated with the inorganic salt hydrate. Solid II exhibits the highest yield of glucose, and therefore levulinic acid, because it has a higher content of structural carbohydrates compared to Solid I and the starting biomass. The main proportion of hemicellulose was dissolved in the pretreatment and remains in the liquid, as depicted previously. However, a very small amount of hemicellulose is present in the solids, so we have detected some products from hemicellulose hydrolysis such as xylose and furfural. In all cases, the amount was very small, with similar profiles (Figures S8, S10, and S12). The xylose profile shows that all samples reach a maximum and then decrease for longer reaction times. This behavior is typical of intermediate behavior in consecutive reactions. Furfural is obtained after dehydration of xylose upon contact with the acid catalyst in the medium. The furfural concentration profiles increase with increasing reaction time. The increase in the reactivity of the treated samples is very small with respect to the original samples, because the main part of the hemicellulose is dissolved in the treatment and remains unreacted. In addition to glucose and xylose, in the hydrolysis process, oligomers with soluble units are obtained due to the breaking of the polymer chains of cellulose and hemicellulose into smaller fragments. For this reason, the final reaction liquid was analyzed (after 5 h of reaction) and the content of total reducing sugars (TRS) was calculated. The obtained results are shown in Table 6, where Solid I and Solid II are compared with their corresponding untreated biomasses. The TRS values are higher than the TRS values obtained after the sum of monomeric sugars provided by the HPLC analysis, showing that there were some oligomers in the reaction medium. This result disagrees with the data from the untreated biomass samples in all cases. Figure 8: Glucose (**A**) and levulinic acid (**B**) yields after the hydrolysis of the original vine shoots and vine shoot solids obtained (Solid I and Solid II) after treatment with ISH. The TRS is greater when the sample has been treated because the chains are more accessible after treatment and it is easier for the acid catalyst to act on them. The yield of sugars, which has been calculated considering the TRS obtained and the maximum total monomeric sugars that can be obtained according to the composition of the corresponding sample, decreases according to the following order: Solid II (rich in structural carbohydrates > Solid I (rich in lignin but with traces of structural carbohydrates) > original biomass, which coincides with the conversion table shown above (Table 5). The selectivity of reducing sugars is higher in Solid II (between 78 and 88% depending on the biomass), which has a greater amount of structural carbohydrates than Solid I and is consistent with data obtained in previous studies with another ionic liquid treatment [10], which were the highest described in the literature [51; 52; 53; 54; 55; 56; 57].