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An expert consensus panel convened by the Italian Association for Inherited and Familial Gastrointestinal Tumors (Associazione Italiana per lo Studio della Familiarita ed Ereditarieta dei Tumori Gastrointestinali, AIFEG) reviewed the literature and agreed on a number of position statements regarding the definition and management of polyposis coli without an identified pathogenic mutation on the APC or MUTYH genes, defined in the document as NAMP (non-APC/MUTYH polyposis).

A biorefinery process was set up to simultaneously produce cellulose nanocrystals (CNCs) and an inorganic-organic material composed by silica and lignin starting from rice husk, a largely available agricultural side product. The opportunity to synthesize this new material, combining lignin and silica at the microscopic level, ensued naturally as the two substances were extracted simultaneously during the process. The main parameters influencing the yield, the composition, and the properties of the lignin-silica material (LSM) were optimized. The overall yield of the process was 35% (12% CNCs and 23% LSM). The sub-micrometric irregular particles constituting the LSM were approximately equally composed by lignin and silica. Larger batches were produced to assess the possibility to use the LSM as a reinforcing biofiller in elastomeric composites based on natural rubber. The lignin-silica material reinforced natural rubber (Ultimate elongation +17%, ultimate strength +198%). The overall effect was rationalized in terms of individual contributions of the two constituents: silica was supposed to contribute largely to the reinforcement, whereas lignin seemed to protect natural rubber from degradation, conveniently enhancing the elongation at break and lowering the total density of the biofiller.

An integrated biorefinery process based on acidic leaching, alkaline treatment and concentrated sulfuric acid hydrolysis was set up for the simultaneous recovery of lignin, hemicelluloses, silica, and cellulose nanocrystals (CNCs) from Arundo donax and rice husk. These fractions can serve as viable source of bio-chemicals with potential high-value applications. A chromatographic and spectroscopic characterization demonstrated that a combined acidic-alkaline treatment enhanced the degradation of lignin-carbohydrates complexes releasing lignin and hemicelluloses in higher yield and purity than the sole alkaline treatment. The remaining cellulose rich solid was bleached through a totally chlorine free process, and then hydrolyzed for cellulose nanocrystals isolation. A. donax cellulose nanocrystals were extracted and characterized for the first time in literature. Moreover, from rice husk, pure amorphous silica was obtained almost in 90% yield and 99% purity, avoiding incineration. In term of mass balance, it was possible to refine the investigated biomasses for the production of lignin, hemicelluloses, silica and CNCs in almost 40% overall yield.