Polymeric Substrates Modification with Biobased Functional Compounds

Editorial to the Special Issue "Polymeric Substrates Modification with Biobased Functional Compounds

Natural Polymers and Cosmeceuticals for a Healthy and Circular Life: The Examples of Chitin, Chitosan, and Lignin

The present review considers the design and introduction of new cosmeceuticals in the market, based on natural polymers and active molecules extracted from biomass, in a biomimetic strategy, starting with a consideration of the biochemical mechanisms, followed by natural precision biopolymer production. After introducing the contest of nanobiotechnology in relationship with its applicability for skin contact products and classifying the currently available sustainable polymers, some widely selected abundant biopolymers (chitin, chitosan, and lignin), showing specific functionalities (anti-microbial, anti-oxidant, anti-inflammatory, etc.), are described, especially considering the possibility to combine them in nanostructured tissues, powders, and coatings for producing new cosmeceuticals, but with potentialities in other sectors, such as biomedical, personal care, and packaging sectors. After observing the general increase in market wellness and beauty forecasts over the next few years, parallelisms between nano and macro scales have suggested that nanobiotechnology application expresses the necessity to follow a better way of producing, selecting, and consuming goods that will help to transform the actual linear economy in a circular economy, based on redesigning, reducing, recycling, and reusing

Evaluation of mechanical and interfacial properties of bio-composites based on poly(lactic acid) with natural cellulose fibers

The circular economy policy and the interest for sustainable material are inducing a constant expansion of the bio-composites market. The opportunity of using natural fibers in bio-based and biodegradable polymeric matrices, derived from industrial and/or agricultural waste, represents a stimulating challenge in the replacement of traditional composites based on fossil sources. The coupling of bioplastics with natural fibers in order to lower costs and promote degradability is one of the primary objectives of research, above all in the packaging and agricultural sectors where large amounts of non-recyclable plastics are generated, inducing a serious problem for plastic disposal and potential accumulation in the environment. Among biopolymers, poly(lactic acid) (PLA) is one of the most used compostable, bio-based polymeric matrices, since it exhibits process ability and mechanical properties compatible with a wide range of applications. In this study, two types of cellulosic fibers were processed with PLA in order to obtain bio-composites with different percentages of microfibers (5%, 10%, 20%). The mechanical properties were evaluated (tensile and impact test), and analytical models were applied in order to estimate the adhesion between matrix and fibers and to predict the material's stiffness. Understanding these properties is of particular importance in order to be able to tune and project the final characteristics of bio-composites

Pullulan for advanced sustainable body- And skin-contact applications

The present review had the aim of describing the methodologies of synthesis and properties of biobased pullulan, a microbial polysaccharide investigated in the last decade because of its interesting potentialities in several applications. After describing the implications of pullulan in nano-technology, biodegradation, compatibility with body and skin, and sustainability, the current applications of pullulan are described, with the aim of assessing the potentialities of this biopolymer in the biomedical, personal care, and cosmetic sector, especially in applications in contact with skin

A comprehensive characterization of Hermetia illucens derived chitosan produced through homogeneous deacetylation

The increasing demand for chitin and chitosan is driving research to explore alternative sources to crustaceans. Insects, particularly bioconverters as Hermetia illucens, are promising substitutes as they process food industry waste into valuable molecules, including chitin. Chitosan can be produced by chitin deacetylation: hot deacetylation to obtain a heterogeneous chitosan, the commonly produced, and cold deacetylation to obtain a homogeneous chitosan, not widely available. The two different treatments lead to a different arrangement of the amine and acetyl groups in the chitosan structure, affecting its molecular weight, deacetylation degree, and biological activity. This is the first report on the production and chemical-physical and biological characterization of homogenous chitosan derived from H. illucens larvae, pupal exuviae, and adults. This work, in addition to the report on heterogeneous chitosan by our research group, completes the overview of H. illucens chitosan. The yield values obtained for homogeneous chitosan from pupal exuviae (3 and 7 %) are in the range of insect (2–8 %) and crustaceans (4–15 %) chitosan. The evaluation of the antioxidant activity and antimicrobial properties against Gram-negative (Escherichia coli) and Gram-positive (Micrococcus flavus) bacteria confirmed the great versatility of H. illucens chitosan for biomedical and industrial applications and its suitability as an alternative source to crustaceans

Electrosprayed shrimp and mushroom nanochitins on cellulose tissue for skin contact application

Cosmetics has recently focused on biobased skin-compatible materials. Materials from natural sources can be used to produce more sustainable skin contact products with enhanced bioactivity. Surface functionalization using natural-based nano/microparticles is thus a subject of study, aimed at better understanding the skin compatibility of many biopolymers also deriving from biowaste. This research investigated electrospray as a method for surface modification of cellulose tissues with chitin nanofibrils (CNs) using two different sources—namely, vegetable (i.e., from fungi), and animal (from crustaceans)—and different solvent systems to obtain a biobased and skin-compatible product. The surface of cellulose tissues was uniformly decorated with electrosprayed CNs. Biological analysis revealed that all treated samples were suitable for skin applications since human dermal keratinocytes (i.e., HaCaT cells) successfully adhered to the processed tissues and were viable after being in contact with released substances in culture media. These results indicate that the use of solvents did not affect the final cytocompatibility due to their effective evaporation during the electrospray process. Such treatments did not also affect the characteristics of cellulose; in addition, they showed promising anti-inflammatory and indirect antimicrobial activity toward dermal keratinocytes in vitro. Specifically, cellulosic substrates decorated with nanochitins from shrimp showed strong immunomodulatory activity by first upregulating then downregulating the pro-inflammatory cytokines, whereas nanochitins from mushrooms displayed an overall anti-inflammatory activity via a slight decrement of the pro-inflammatory cytokines and increment of the anti-inflammatory marker. Electrospray could represent a green method for surface modification of sustainable and biofunctional skincare products

New physical characterization of the Fontana Lapilli basaltic Plinian eruption, Nicaragua

The Fontana Lapilli deposit was erupted in the late Pleistocene from a vent, or multiple vents, located near Masaya volcano (Nicaragua) and is the product of one of the largest basaltic Plinian eruptions studied so far. This eruption evolved from an initial sequence of fluctuating fountain-like events and moderately explosive pulses to a sustained Plinian episode depositing fall beds of highly vesicular basaltic-andesite scoria (SiO2 > 53 wt%). Samples show unimodal grain size distribution and a moderate sorting that are uniform in time. The juvenile component predominates (> 96 wt%) and consists of vesicular clasts with both sub-angular and fluidal, elongated shapes. We obtain a maximum plume height of 32 km and an associated mass eruption rate of 1.4 × 108 kg s−1 for the Plinian phase. Estimates of erupted volume are strongly sensitive to the technique used for the calculation and to the distribution of field data. Our best estimate for the erupted volume of the majority of the climactic Plinian phase is between 2.9 and 3.8 km3 and was obtained by applying a power-law fitting technique with different integration limits. The estimated eruption duration varies between 4 and 6 h. Marine-core data confirm that the tephra thinning is better fitted by a power-law than by an exponential trend