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This review article was prompted by a remarkable growth in the number of scientific publications dealing with the use of nanocellulose (especially nanofibrillated cellulose (NFC), cellulose nanocrystals (CNC), and bacterial cellulose (BC)) to enhance the barrier properties and other performance attributes of new generations of packaging products. Recent research has confirmed and extended what is known about oxygen barrier and water vapor transmission performance, strength properties, and the susceptibility of nanocellulose-based films and coatings to the presence of humidity or moisture. Recent research also points to various promising strategies to prepare ecologically-friendly packaging materials, taking advantage of nanocellulose-based layers, to compete in an arena that has long been dominated by synthetic plastics. Some promising approaches entail usage of multiple layers of different materials or additives such as waxes, high-aspect ratio nano-clays, and surface-active compounds in addition to the nanocellulose material.While various high-end applications may be achieved by chemical derivatization or grafting of the nanocellulose, the current trends in research suggest that high-volume implementation will likely incorporate water-based formulations, which may include water-based dispersions or emulsions, depending on the enduses. Resources; North Carolina State University, Raleigh, NC 27695, USA; b: Nalco Champion, an Ecolab Company, 7705 Highway 90-A, Sugar Land, TX 77478, USA; c: School of Clothing and Textiles, Jiangnan University, Wuxi, Jiangsu, China; d: Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, PO Box 16300, FI-00076 Aalto, Finland; * Corresponding author: hubbe@ncsu Table B -Barrier properties of NFC films 2144 2145 2145 2149 2151 2152 2153 2155 2155 2157 2157 2158 2158 2159 2159 2166 2170 2172 2173 2174 2175 2177 2179 2208 2208 2228 REVIEW ARTICLE bioresources.com . "Nanocellulose in packaging," BioResources 12(1), 2143-2233. 2144 Keywords: Barrier properties; Water vapor transmission; Food shelf life; Oxygen transmission; Packages; Cellulose nanomaterials Contact information: a: Department of Forest Biomaterials, College of Natural INTRODUCTIONThere has been explosive growth in the publication of peer-reviewed articles that combine key words related to "packaging" and "cellulose," in combination with the terms "nanocellulose," "nanocrystal*," or "nanofibril*". As of November 2016, a search of this combination of terms showed about as many publications since the start of 2015, compared to all preceding years combined. Given such an acceleration of research around the world, it makes sense to ask whether this high amount of research effort has yet borne significant fruit. In light of this question, the emphasis of this review article is on research publications that shed light on known challenges to the successful implementation of nanocellulose products to enhance the performance of packaging.In principle, a nano...

Lignins are used often in formulations involving proteins but little is known about the surface interactions between these important biomacromolecules. In this work, we investigate the interactions at the solid-liquid interface of lignin with the two main proteins in soy, glycinin (11S) and β-conglycinin (7S). The extent of adsorption of 11S and 7S onto lignin films and the degree of hydration of the interfacial layers is quantified via Quartz crystal microgravimetry (QCM) and surface plasmon resonance (SPR). Solution ionic strength and protein denaturation (2-mercaptoethanol and urea) critically affect the adsorption process as protein molecules undergo conformational changes and their hydrophobic or hydrophilic amino acid residues interact with the surrounding medium. In general, the adsorption of the undenatured proteins onto lignin is more extensive compared to that of the denatured biomolecules and a large amount of water is coupled to the adsorbed molecules. The reduction in water contact angle after protein adsorption (by ~40° and 35° for undenatured 11S and 7S, respectively) is explained by strong nonspecific interactions between soy proteins and lignin.

A molecular linkage map of cultivated oat composed of 561 loci has been developed using 71 recombinant inbred lines from a cross between Avena byzantina cv. Kanota and A. sativa cv. Ogle. The loci are mainly restriction fragment length polymorphisms detected by oat cDNA clones from leaf, endosperm, and root tissue, as well as by barley leaf cDNA clones. The loci form 38 linkage groups ranging in size from 0.0 to 122.1 cM (mean, 39 cM) and consist of 2-51 loci each (mean, 14). Twenty-nine loci remain unlinked. The current map size is 1482 cM and the total size, on the basis of the number of unlinked loci, is estimated to be 2932.0 cM. This indicates that this map covers at least 50% of the cultivated oat genome. Comparisons with an A-genome diploid oat map and between linkage groups exhibiting homoeology to each other indicate that several major chromosomal rearrangements exist in cultivated oat. This map provides a tool for marker-assisted selection, quantitative trait loci analyses, and studies of genome organization in oat.

Cellulose nanofi brils (CNF), also known as nanofi brillar cellulose (NFC), are an advanced biomaterial made mainly from renewable forest and agricultural resources that have demonstrated exceptional performance in composites. In addition, they have been utilized in barrier coatings, food, transparent fl exible fi lms and other applications. Research on CNF has advanced rapidly over the last decade and several of the fundamental questions about production and characterization of CNF have been addressed. An interesting shift in focus in the recent reported literature indicates increased efforts aimed at taking advantage of the unique properties of CNF. This includes its nanoscale dimensions, high surface area, unique morphology, low density and mechanical strength. In addition, CNF can be easily (chemically) modified and is readily available, renewable, and biodegradable. These facts are expected to materialize in a more widespread use of CNF. However, there is no clear indication of the most promising avenues for CNF deployment in commercial products. This review attempts to illustrate some exciting opportunities for CNF, specifi cally, in the development of aerogels, composites, bioactive materials and inorganic/organic hybrid materials.