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The exponential increase of waste derived from different human activities points out the importance of their reuse in order to create materials with specific properties that can be used for different applications. In this work, it was showed how the typical Mediterranean organic liquid waste, namely olive mill wastewater (OMWW), obtained during olive oil production, can be turned into an efficient reactive agent for the production of noble metals gold (Au) and silver nanoparticles (Ag NPs) with very well-defined physico-chemical properties. More than that, it was demonstrated that this synthetic procedure also leads to a drastic decrease of the organic pollution load of the OMWW, making it safer for environmental disposal and plants irrigation. Then, using healthy hepatic cell line mitochondria, the biological effects induced by these green metal NPs surrounded by a polyphenols shell, with the same NPs synthetized through a standard chemical colloidal reduction process, were compared, finding out that the green NPs are much safer. Graphical abstract: [Figure not available: see fulltext.].

Noble metals nanoparticles (NPs) and metal oxide NPs are widely used in different fields of application and commercial products, exposing living organisms to their potential adverse effects. Recent evidences suggest their presence in the aquifers water and consequently in drinking water. In this work, we have carefully synthesized four types of NPs, namely, silver and gold NPs (Ag NPs and Au NPs) and silica and titanium dioxide NPs (SiO2 NPs and TiO2 NPs) having a similar size and negatively charged surfaces. The synthesis of Ag NPs and Au NPs was carried out by colloidal route using silver nitrate (AgNO3) and tetrachloroauric (III) acid (HAuCl4) while SiO2 NPs and TiO2 NPs were achieved by ternary microemulsion and sol-gel routes, respectively. Once the characterization of NPs was carried out in order to assess their physico-chemical properties, their impact on living cells was studied. We used the human colorectal adenocarcinoma cells (Caco-2), known as the best representative intestinal epithelial barrier model to understand the effects triggered by NPs through ingestion. Then, we moved to explore how water contamination caused by NPs can be lowered by the ability of three species of aquatic moss, namely, Leptodictyum riparium, Vesicularia ferriei, and Taxiphyllum barbieri, to absorb them. The experiments were conducted using two concentrations of NPs (100 μM and 500 Μm as metal content) and two time points (24 h and 48 h), showing a capture rate dependent on the moss species and NPs type. Then, the selected moss species, able to actively capture NPs, appear as a powerful tool capable to purify water from nanostructured materials, and then, to reduce the toxicity associated to the ingestion of contaminated drinking water.

The agronomic and qualitative responses of the cherimoya (Annona cherimola Mill.) fruit grown in Mediterranean climate are not properly studied. Fruits of Fino de Jete, the most diffused worldwide cultivar of cherimoya, and Torre 1 a new genotype obtained by breeding program in Sicily, Italy, were collected at commercial ripening and subjected to productive (yield efficiency, number of fruits, crop load), analytical (fruit weight, transversal diameter, longitudinal diameter, total soluble solid content, titratable acidity, seed weight, seed number, peel and pulp weight, pulp/seed ratio and colorimetric analysis), bioactive compound content (total antioxidant activity, Phenolic and Carotenoid) and sensory evaluations by a semi-trained panel, recorded over two productive seasons. Even if the climatic conditions prevailing in Sicily differ from those of most cherimoya-growing regions, the two observed cultivars generally showed yields and fruit qualitative characteristics comparable with those harvested in other Mediterranean and Tropical areas. Fino de Jete confirmed its quality standard thanks to its yields performance and fruit weight. Despite of this, Torre 1 showed interesting physico-chemical, sensory properties and bioactive compounds, suitable for the consumer needs: less number of seeds and better pulp/seed ratio, better total solid soluble content/tritratable acidity ratio, higher phenolic content and antioxidant activity. These results suggest that cherimoya can be cropped for fresh production in Mediterranean environment with promising yields and good standards of fruit quality.

Resistance to antibiotics is one of the main current threats to human health and every year multi-drug resistant bacteria are infecting millions of people worldwide, with many dying as a result. Ever since their discovery, some 40 years ago, the antimicrobial peptides (AMPs) of innate defense have been hailed as a potential alternative to conventional antibiotics due to their relatively low potential to elicit resistance. Despite continued effort by both academia and start-ups, currently there are still no antibiotics based on AMPs in use. In this study, we discuss what we know and what we do not know about these agents, and what we need to know to successfully translate discovery to application. Understanding the complex mechanics of action of these peptides is the main prerequisite for identifying and/or designing or redesigning novel molecules with potent biological activity. However, other aspects also need to be well elucidated, i.e., the (bio)synthetic processes, physiological and pathological contexts of their activity, and a quantitative understanding of how physico-chemical properties affect activity. Research groups worldwide are using biological, biophysical, and algorithmic techniques to develop models aimed at designing molecules with the necessary blend of antimicrobial potency and low toxicity. Shedding light on some open questions may contribute toward improving this process.

Simple Summary Polyphenols are present in a broad variety of plants, and they are known to possess anti-inflammation and anticancer properties. We used extracts from Laurus nobilis to synthetize gold nanoparticles (Au NPs), on which polyphenols were absorbed to form a stable shell (Au NPs@polyphenols). Then, the macrophage inflammation response was assessed, with the aim of using the Au NPs@polyphenols as synergistic tools in the thermal treatment of cancer cell models. We showed that the thermal conductivity enhancement, induced by Au during thermal treatment, increased the anticancer effects of polyphenols. After demonstrating the effectiveness of this system in in vitro cancer cell models, the future challenge will be the in vivo application of Au NPs@polyphenols. Abstract Background: In recent decades, gold nanoparticle (Au NP)-based cancer therapy has been heavily debated. The physico-chemical properties of AuNPs can be exploited in photothermal therapy, making them a powerful tool for selectively killing cancer cells. However, the synthetic side products and capping agents often induce a strong activation of the inflammatory pathways of macrophages, thus limiting their further applications in vivo. Methods: Here, we described a green method to obtain stable polyphenol-capped AuNPs (Au NPs@polyphenols), as polyphenols are known for their anti-inflammatory and anticancer properties. These NPs were used in human macrophages to test key inflammation-related markers, such as NF-κB, TNF-α, and interleukins-6 and 8. The results were compared with similar NPs obtained by a traditional chemical route (without the polyphenol coating), proving the potential of Au NPs@polyphenols to strongly promote the shutdown of inflammation. This was useful in developing them for use as heat-synergized tools in the thermal treatment of two types of cancer cells, namely, breast cancer (MCF-7) and neuroblastoma (SH-SY5Y) cells. The cell viability, calcium release, oxidative stress, HSP-70 expression, mitochondrial, and DNA damage, as well as cytoskeleton alteration, were evaluated. Results: Our results clearly demonstrate that the combined strategy markedly exerts anticancer effects against the tested cancer cell, while neither of the single treatments (only heat or only NPs) induced significant changes. Conclusions: Au NP@polyphenols may be powerful agents in cancer treatment.

Hybrid Melanin-TiO2 nanoparticles are promising bioinspired antibacterial agents for biomedical coatings and food-packaging fields. However, due to a very low colloidal stability, they showed a high tendency to self-aggregate and rapidly precipitate, making not easy their use in aqueous medium to produce homogeneous antimicrobial coatings or nanocomposites. A valid strategy to improve their dispersion is the combination with a hydrophilic water-soluble polymer such as poly-vinyl-alcohol (PVA), which is a good choice to improve the colloidal stability of nanoparticles and to modulate their agglomeration. In this work, we propose an in-situ synthetic approach based on the hydrothermal route, by which the hybrid Melanin-TiO2 nanoparticles were prepared starting from the inorganic and organic precursors in the presence of PVA. Combined approach of TEM, XRD, TG/DSC, EPR and DLS techniques allows for assessing the PVA role in the formation of hybrids and on their morphological features as well as colloidal stability and aqueous dispersion. Antibacterial tests demonstrated the biocide activity of PVA/Melanin-TiO2 nanoparticles against Escherichia coli bacterial cultures, which resulted partially influenced by the PVA content. This study provides key information on the mutual influence of organic/inorganic components on the functional properties of the final hybrid nanocomposites, contributing to define a much more far-reaching implementation in the synthesis of bioinspired polymer-based nanocomposites.

Edible films and coatings gained renewed interest in the food packaging sector with polysaccharide and protein blending being explored as a promising strategy to improve properties of edible films. The present work studies composite edible films in different proportions of pectin (P), alginate (A) and whey Protein concentrate (WP) formulated with a simplex centroid mixture design and evaluated for physico-chemical characteristics to understand the effects of individual components on the final film performance. The studied matrices exhibited good film forming capacity, except for whey protein at a certain concentration, with thickness, elastic and optical properties correlated to the initial solution viscosity. A whey protein component in general lowered the viscosity of the initial solutions compared to that of alginate or pectin solutions. Subsequently, a whey protein component lowered the mechanical strength, as well as the affinity for water, as evidenced from an increasing contact angle. The effect of pectin was reflected in the yellowness index, whereas alginate and whey protein affected the opacity of film. Whey protein favored higher opacity, lower gas barrier values and dense structures, resulting from the polysaccharide-protein aggregates. All films displayed however good thermal stability, with degradation onset temperatures higher than 170 &deg, C.

The wide use of engineered nanomaterials in many fields, ranging from biomedical, agriculture, environment, cosmetic, urged the scientific community to understand the processes behind their potential toxicity, in order to develop new strategies for human safety. As a matter of fact, there is a big discrepancy between the increased classes of nanoparticles and the consequent applications versus their toxicity assessment. Nanotoxicology is defined as the science that studies the effects of engineered nanodevices and nanostructures in living organisms. This chapter analyzes the physico-chemical properties of the most used nanoparticles, the way they enter the living organism and their cytoxicity mechanisms at cellular exposure level. Moreover, the current state of nanoparticles risk assessment is reported and analyzed.

In the present research work, non-edible oil source Aamla plant was systematically identified for biodiesel production. The extracted oil percentage was achieved by up to 37.22% of the total dry seed weight. The free fatty acid content of crude oil was reduced from 4.12 mg KOH/g to 0.13 mg KOH/g, using esterification before the synthesis of biodiesel. The highest conversion yields of biodiesel were achieved at 88.77 & 90.31%, respectively using solid base catalyst oxides. The protocol for experiments was adjusted as follows: temperature (60 °C); different catalysts with various concentrations, time of reaction (2 h), stirring velocity (600 rpm) and 1:6 oil molar ratios. Qualitatively, the prepared biodiesel was characterized by GC chromatography, 13C & 1H NMR, FT-IR and AAS spectroscopy. In terms of fuel properties, the kinematic viscosity, density, Cloud Point, Pour Point, Cold Filter Plugging Point, acid number, Flash Point and cetane number of prepared biodiesel, its 4 blends i.e. B5, B10, B15 & B20 and petro-diesel sample were tested and compared with ASTM D6751 and EN 14214 standards. © 2015 Elsevier B.V. All rights reserved.

Introduction - The agronomic and qualitative responses of the litchi fruit (Litchi chinensis Sonn.) grown in Mediterranean climate are not yet studied. In this study, yield components, physico-chemical and sensory traits of four commercial litchi cultivars were recorded over two productive seasons. Materials and methods - Fruits of the cvs Tai So, Wai Chee, Brewster and Kwai Mai were collected at commercial maturity stage and subjected to productive (yield, efficiency, number of fruits, crop load), analytical (fruit weight, transversal diameter, longitudinal diameter, moisture, total soluble solid content (TSS), titratable acidity (TA), TSS/TA ratio, seed weight, peel weight, percentage of flesh and fiber, ash, fat, protein contents, K, Na, Ca, Mg, P, Fe, Cu, Mn and Zn contents, vitamin B1, B2, B3and C contents), and sensory evaluations. Results and discussion - Even if the climatic conditions prevailing in Sicily differ from those of most litchi-growing regions, the four observed cultivars generally showed yields and fruit qualitative characteristics in line with the affirmed cultivar harvested in many tropical areas. 'Tai So' in addition to its reasonable yielding, physicochemical traits, contents of protein and vitamin, had the highest sensory appeal. 'Kwai Mai' showed interesting percentage of flesh, TSS/TA and flesh mineral composition. 'Brewster' and 'Wai Chee' revealed interesting ground colour, vit. B2and vit. C contents. On the other hand, 'Brewster' and 'Tai So' presented alternate bearing causing to lose a market year. Conclusion - These results suggest the possibility to produce litchi in Mediterranean climate with promising yields and an elevated standard of fruit quality.

Some agricultural residues such as wheat or barley straw, as well as certain fast-growing plants like Leucaena leucocephala and Chamaecytisus proliferus, could be used as raw materials for the paper industry as an alternative to traditional plants (eucalyptus, pine, etc.). In the present study, four types of lignin obtained from the spent liquors produced by the pulping processes using the abovementioned feedstocks were isolated and characterized. Lignin samples were acquired through an acid precipitation from these spent liquors. The characterization of the precipitated lignin samples were performed using a Fourier transform infrared spectroscopy (FT-IR) and both liquid- and solid-state nuclear magnetic resonance spectroscopy (NMR) to analyse the chemical structure, and thermogravimetric analysis (TGA) for determining the thermal properties. Additionally, chemical composition of lignin fractions was also measured. Even though they were of different botanical origin, all the studied samples except for wheat straw lignin had a similar chemical composition and thermal behaviour, and identical chemical structure. Wheat straw lignin showed a greater amount of Klason lignin and lower carbohydrate content. Furthermore, this lignin sample showed a higher thermal stability and significantly different cross-peak patterns in the 2D-NMR experiments. The molecular structures corresponding to p-coumarate (PCA), ferulate (FA) and cinnamyl aldehyde end-groups (J) were only detected in wheat isolated lignin

The objective of this paper is to emphasize the fact that while consistent interest has been paid to the industrial use of chitosan, minor attention has been devoted to spread the knowledge of a good characterization of its physico-chemical properties. Therefore, the paper attempts to critically comment on the conflicting experimental results, highlighting the facts, the myths and the controversies. The goal is to indicate how to take advantage of chitosan versatility, to learn how to manage its variability and show how to properly tackle some unexpected undesirable features. In the sections of the paper various issues that relate chitosan properties to some basic features and to advanced solutions and applications are presented. The introduction outlines some historical pioneering works, where the chemistry of chitosan was originally explored. Thereafter, particular reference is made to analytical purity, characterization and chain modifications. The macromolecular characterization is mostly related to molecular weight and to degree of acetylation, but also refers to the conformational and rheological properties and solution stability. Then, the antimicrobial activity of chitosan in relation with its solubility is reviewed. A section is dedicated to the formulation of chitosan biomaterials, from gel to nanobeads, exploring their innovative application as active carrier nanoparticles. Finally, the toxicity issue of chitosan as a polymer and as a constructed nanomaterial is briefly commented in the conclusions.

Olive mill waste water (OMW), a by-product of the olive mill industry, is produced in large amounts in Mediterranean countries. Olive mill waste water contains a high organic load, substantial amounts of plant nutrients but also several compounds with recognized toxicity towards living organisms. Moreover, OMW may represent a low cost source of water. Thus, the use of OMW for soil fertigation is a valuable option for its disposal, provided that its impact on soil chemical and biochemical properties is established. Investigations were performed on the short-term influence of OMW on several chemical and biochemical properties of a soil from a continental semi-arid Mediterranean region (Morocco). The soil was amended with 0, 18 and 36 ml 100 g −1 soil of OMW (corresponding to a field rate of 0, 40 and 80 m 3 ha −1 , respectively) and changes in various functionally related properties such as microbial biomass, basal respiration, extractable C and N, and soil hydrolases and oxido-reductases activities were measured over time. The variations of the main physical and chemical properties as well as the residual phytotoxicity of OMW amended and non-amended soils as assessed by tomato seed germination tests were also monitored. Temporary and permanent changes in several chemical and biochemical soil properties occurred following OMW application, thus being these properties varied in sensitivity to the applied disturbance. A sudden increase of total organic C, extractable N and C, available P and extractable Mn and Fe contents were measured. Simultaneously, a rapid increase of soil respiration, dehydrogenase and urease activities and microbial biomass (at 14 day incubation) of OMW amended soils occurred. In contrast, the activities of phosphatase, β-glucosidase, nitrate reductase and diphenol oxidase decreased markedly. The soil became highly phytotoxic after OMW addition (large decline of soil germination capability), mainly at 80 m 3 ha −1 OMW. After 42 days' incubation, however, a complete recovery of the soil germination capability and a residual phytotoxicity of about 30% were observed with 40 and 80 m 3 ha −1 OMW, respectively. These findings indicate that the impact of OMW on soil properties was the result of opposite effects, depending on the relative amounts of beneficial and toxic organic and inorganic compounds present. The toxic compounds contained in OMW most likely counteracted the beneficial effect of organic substrates provided, which promoted the growth and activity of indigenous microorganisms.