ABSTRACT
Cellulose fibers can be freed from the cell-wall skeleton via high-shear homogenization, to produce cellulose nanofibers (CNF) that can be used, for example, as the reinforcing phase in composite materials. Nanofiber production from agro-industrial byproducts normally involves harsh chemical-pretreatments and high temperatures to remove noncellulosic polysaccharides (20-70% of dry weight). However, this is expensive for large-scale processing and environmentally damaging. An enzyme-only pretreatment to obtain CNF from agro-industrial byproducts (potato and sugar beet) was developed with targeted commercial enzyme mixtures. It is hypothesized that cellulose can be isolated from the biomass, using enzymes only, due to the low lignin content, facilitating greater liberation of CNF via high-shear homogenization. Comprehensive Microarray Polymer Profiling (CoMPP) measured remaining extractable polysaccharides, showing that the enzyme-pretreatment was more successful at removing noncellulosic polysaccharides than alkaline- or acid-hydrolysis alone. While effective alone, the effect of the enzyme-pretreatment was bolstered via combination with a mild high-pH pretreatment. Dynamic rheology was used to estimate the proportion of CNF in resultant suspensions. Enzyme-pretreated suspensions showed 4-fold and 10-fold increases in the storage modulus for potato and sugar beet, respectively, compared to untreated samples. A greener yet facile method for producing CNF from vegetable waste is presented here.
Subject(s)
Biotechnology/methods , Cellulose/analogs & derivatives , Industrial Waste , Nanofibers/chemistry , Vegetables/chemistry , Beta vulgaris/chemistry , Biocatalysis , Hydrolysis , Solanum tuberosum/chemistryABSTRACT
Five hundred eighty-six patients with epilepsy were treated with borax (hydrated sodium tetraborate) between 1912 and 1948 at the Kolonien Filadelfia Epilepsy Hospital, Dianalund, Denmark. A rough estimation shows that less than 5% experienced a more than 50% reduction in the total number of seizures. Charts were reviewed to find a connection between the concept of Bacillus epilepticus (1916) and the so-called renaissance of borax treatment described in 1923, and to find an explanation for the popularity of this seemingly ineffective antiepileptic drug.
