## 3 Results and Discussion  
### CNC and LNP Synthesis  
Previously described protocols turned out to be adequate to synthesize CNC from both HP and HS (Figure 1). In terms of yield (calculated as percentage ratio between the weights of final cellulosic masses and initial raw materials) obtained, CPC-HP was about 28.2 \(\pm\) 1.7%, while CPC-HS showed a final yield of 23.9 \(\pm\) 2.3%. The acid hydrolysis yield, calculated using the method reported as UNI EN ISO 638:2009, was, respectively, 31.8 \(\pm\) 0.9% and 8.3 \(\pm\) 1.5% for HP CNC and HS CNC. While the obtained results for the pruning shoots seem to match the cellulose content in hazelnut branches and suckers, highlighting the appropriateness of the adopted protocol to isolate cellulose from the raw materials in terms of purity and quantity, the CNC yield is much lower when using the lignocellulosic biomasses coming from hazelnut shelling. To explain these results, we should first consider the different lignocellulosic composition of the shells, which have a smaller content of cellulose than the pruning shoots. Furthermore, the presence of a recalcitrant component mainly made of waves could have played an import role in making the matrix more inaccessible to the chemical reagents. There is evidence for this in the characterization analysis of CNC, which have demonstrated a more relevant presence of impurities and foreign substances in HS samples than in HP ones, as described in the following paragraph. In spite of everything, it is important to say that the reported approaches can be considered a successful first step to obtain cellulose and its crystalline nanoform from both hazelnut pruning and shelling waste. More improvements are being studied to enhance the CNC extraction and yield, such as including a more effective dewaxing treatment for HS, as it happened for other nuts residues, or diminishing the amount of used chemical reagents, in order to develop a more sustainable process.  
LNPs were synthesized according to the extraction protocols described in the Section 2.2.2 (Figure 2). The isolated lignin fractions showed a yield (calculated as percentage ratio between the weights of final ligninic masses and initial raw materials) of 4.1 \(\pm\) 0.8% and 3.1 \(\pm\) 0.5%, respectively, for HS and HP, while the final LNP yield (calculated as reported in the method UNI EN ISO 638:2009, after adding the final weights of the different LNP extractions) was about 79.9 \(\pm\) 1.8% and 39.9 \(\pm\) 1.7% for HP and HS, respectively. The proposed approaches of using an enzymatic pretreatment to isolate the lignin component from the lignocellulosic waste seems to be a very promising one since most common LNP synthesis protocols are based on large consumption of chemical reagents [46; 73; 74]. Nevertheless, more work is needed to enhance yield of the extraction process. The solvent-antisolvent method is based on the use of water and ethanol allowed to synthesize LNP without using heavy chemical reagents, with acceptable yields. The one concerning HS is much lower than HP since the starting matrix is composed of waves and other lipid fractions that lower the efficacy of the proposed treatments [75; 76]. In this sense, a much more effective dewaxing pretreatment is required in order to be able to exploit all the ligninic fraction in shells.