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The aim of the present study was to investigate starch-based materials, prepared in an environmentally friendly way and from renewable resources, suitable for the development of biodegradable active food packaging. For this purpose, a bioactive compound (thymol) was incorporated into thermoplastic starch (TPS) and a TPS blend with poly (ε-caprolactone) (TPS-PCL) by the supercritical CO

Edible polymers such as polysaccharides, proteins, and lipids are biodegradable and biocompatible materials applied as a thin layer to the surface of food or inside the package. They enhance food quality by prolonging its shelf-life and avoiding the deterioration phenomena caused by oxidation, humidity, and microbial activity. In order to improve the biopolymer performance, antimicrobial agents and plasticizers are also included in the formulation of the main compounds utilized for edible coating packages. Secondary natural compounds (SC) are molecules not essential for growth produced by some plants, fungi, and microorganisms. SC derived from plants and fungi have attracted much attention in the food packaging industry because of their natural antimicrobial and antioxidant activities and their effect on the biofilm’s mechanical properties. The antimicrobial and antioxidant activities inhibit pathogenic microorganism growth and protect food from oxidation. Furthermore, based on the biopolymer and SC used in the formulation, their specific mass ratio, the peculiar physical interaction occurring between their functional groups, and the experimental procedure adopted for edible coating preparation, the final properties as mechanical resistance and gas barrier properties can be opportunely modulated. This review summarizes the investigations on the antimicrobial, mechanical, and barrier properties of the secondary natural compounds employed in edible biopolymer-based systems used for food packaging materials.

In this study, a novel extraction method has been employed to obtain highly efficient cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs) from waste hemp fibers with maximum potential. By...

The aim of the present study was to investigate starch-based materials, prepared in an environmentally friendly way and from renewable resources, suitable for the development of biodegradable active food packaging. For this purpose, a bioactive compound (thymol) was incorporated into thermoplastic starch (TPS) and a TPS blend with poly (ε-caprolactone) (TPS–PCL) by the supercritical CO2 (scCO2) impregnation process. Impregnation experiments with scCO2 were carried out at a pressure of 30 MPa and temperatures in the range of 40–100 °C during 1 to 20 h. The structural, morphological, and thermal properties of the obtained materials were comprehensively evaluated. Bioactive component release kinetic studies were performed in water at 6 °C and 25 °C. It was shown that the scCO2 impregnation process could be successfully employed for thymol loading into TPS and TPS–PCL. The process was significantly influenced by the operating temperature and time as well as content of PCL. The samples showed a controlled release of thymol within seven days with a higher amount of released thymol from the TPS–PCL blend. The obtained materials are solvent-free and release the bioactive component in a controlled manner.

Since the potentialities of applications of low molecular weight poly-γ-glutamic acid (γ-PGA) chains have been so far only partially explored, the separation of diverse molecular families of them, as well as their characterization for potential bioactivity and ability to form films, were investigated. Two different approaches based on organic solvent precipitation or on ultra- and nano-filtration membrane-based purification of inexpensive commercial material were employed to obtain size-specific γ-PGA fractions, further characterized by size exclusion chromatography equipped with a triple detector array and by ultra-high-performance liquid chromatography to assess their average molecular weight and their concentration. The γ-PGA low molecular weight fractions, purified by ultra-filtration, have been shown both to counteract the desiccation and the oxidative stress of keratinocyte monolayers. In addition, they were exploited to prepare novel hydrocolloid films by both solvent casting and thermal compression, in the presence of different concentrations of glycerol used as plasticizer. These biomaterials were characterized for their hydrophilicity, thermal and mechanical properties. The hot compression led to the attainment of less resistant but more extensible films. However, in all cases, an increase in elongation at break as a function of the glycerol content was observed. Besides, the thermal analyses of hot compressed materials demonstrated that thermal stability was increased with higher γ-PGA distribution po-lymer fractions. The obtained biomaterials might be potentially useful for applications in cosmetics and as vehicle of active molecules in the pharmaceutical field.

Neofusiccocum batangarum is the causal agent of scabby canker of cactus pear (Opuntia ficus-indica L.). The symptoms of this disease are characterized by crusty, perennial cankers, with a leathery, brown halo. Characteristically, a viscous polysaccharide exudate, caking on contact with air, leaks from cankers and forms strips or cerebriform masses on the surface of cactus pear cladodes. When this polysaccharide mass was partial purified, surprisingly, generated a gel. The TLC analysis and the HPLC profile of methyl 2-(polyhydroxyalkyl)-3-(o-tolylthiocarbomoyl)-thiazolidine-4R-carboxylates obtained from the mixture of monosaccharides produced by acid hydrolysis of the three EPSs examined in this research work [the polysaccharide component of the exudate (EPSC) and the EPSs extracted from asymptomatic (EPSH) and symptomatic (EPSD) cladodes] showed the presence of d-galactose, l-rhamnose, and d-glucose in a 1:1:0.5 ratio in EPSC while d-galactose, l-rhamnose, d-glucose, and d-xylose at the same ratio were observed in EPSH and EPSD. The presence of uronic acid residues in EPSC was also showed by solid state NMR and IR investigation. Furthermore, this manuscript reports the chemical-physical characterization of the gel produced by the infected cactus pear.

Cardoon, Cynara cardunculus L. represents a biorefinery crop with a great potential in the bioplastic field. This work investigates the valorization of different cardoon components into high added value products, finally recombined into novel upgraded bioplastics. Bioprocesses for Polyhydroxybutyrate (PHB) and medium-chain-length Polyhydroxyalkanoates (mcl-PHA) production were set up starting from root inulin and seed oil respectively, highlighting the effect of process conditions on polymer properties. The ternary blend, in which the PHB polymer matrix was added with mcl-PHA and epoxidized cardoon oil, evidenced a synergic effect of both additives in modulating PHB structural and thermal properties, promoted by the physical interaction occurring among the components. This proof-of concept frames the paper in the holistic approach of circular economy applied to bioplastic production.

Bio-based composites made of poly(L-lactic acid) (PLLA) and β-cyclodextrin/d-limonene inclusion complex (CD-Lim) were prepared by melt extrusion. Encapsulation of volatile d-limonene molecules within β-cyclodextrin cages was proven to be a successful strategy to prevent evaporation during high-temperature processing. However, small amounts of limonene were released upon processing, resulting in the plasticization of the polymeric matrix. Morphological analysis revealed good dispersion of the filler, which acted as a nucleating agent, favoring the growth of PLLA crystals. The composites′ lowered glass transition temperature upon the addition of CD-Lim was also proved by thermomechanical analysis (DMA). Moreover, DMA revealed constant stiffness of modified materials at room temperature, which is crucial in PLLA-based formulations.

The transition toward “green” alternatives to petroleum-based plastics is driven by the need for “drop-in” replacement materials able to combine characteristics of existing plastics with biodegradability and renewability features. Promising alternatives are the polyhydroxyalkanoates (PHAs), microbial biodegradable polyesters produced by a wide range of microorganisms as carbon, energy, and redox storage material, displaying properties very close to fossil-fuel-derived polyolefins. Among PHAs, polyhydroxybutyrate (PHB) is by far the most well-studied polymer. PHB is a thermoplastic polyester, with very narrow processability window, due to very low resistance to thermal degradation. Since the melting temperature of PHB is around 170–180°C, the processing temperature should be at least 180–190°C. The thermal degradation of PHB at these temperatures proceeds very quickly, causing a rapid decrease in its molecular weight. Moreover, due to its high crystallinity, PHB is stiff and brittle resulting in very poor mechanical properties with low extension at break, which limits its range of application. A further limit to the effective exploitation of these polymers is related to their production costs, which is mostly affected by the costs of the starting feedstocks. Since the first identification of PHB, researchers have faced these issues, and several strategies to improve the processability and reduce brittleness of this polymer have been developed. These approaches range from thein vivosynthesis of PHA copolymers, to the enhancement ofpost-synthesisPHB-based material performances, thus the addition of additives and plasticizers, acting on the crystallization process as well as on polymer glass transition temperature. In addition, reactive polymer blending with other bio-based polymers represents a versatile approach to modulate polymer properties while preserving its biodegradability. This review examines the state of the art of PHA processing, shedding light on the green and cost-effective tailored strategies aimed at modulating and optimizing polymer performances. Pioneering examples in this field will be examined, and prospects and challenges for their exploitation will be presented. Furthermore, since the establishment of a PHA-based industry passes through the designing of cost-competitive production processes, this review will inspect reported examples assessing this economic aspect, examining the most recent progresses toward process sustainability.

In this study, mixtures based on β-glucans and proteins are extracted from barley, in mild (MA) and high (HA) alkaline conditions, and employed with zinc oxide (ZnO) to prepare bioactive films for wound healing. Composition of extracts and properties of resulting films depend on pH extraction conditions. MA based samples show weak physical interactions among mixture components, whereas in HA films the extent of these interactions is larger. Consequently, their chemico-physical properties are significantly different, as demonstrated by FT-IR, thermal, mechanical and morphological analyses. ZnO with its bound water molecules acts as a slight plasticizer in MA, as shown by the lower Tg and the decrease of elastic modulus. In HA, this effect is evidenced up to ZnO 1%, and above this concentration an increase of strength at break is observed. Finally, MA and HA films show intrinsic antimicrobial properties, enhanced by ZnO, which make them exploitable as wound dressings.

Introduction Barley is one of the most produced and cultivated cereal crops worldwide. Its grains are mainly composed by proteins and polysaccharides, in particular ?-glucans that are linear polysaccharides showing hypocholesterolemic and hypoglycemic activity and having interesting antimicrobial and wound healing properties. However, the process of extraction and purification for isolating ?-glucans from the other components is complex, expensive and may cause polymer chain degradations. In light of this, the aim of this work was the development of low-cost simultaneous extractions of proteins and polysaccharides from barley by-products, to prevent polymer degradation. It is well known that ZnO is widely used to prevent or treat topical and systemic diseases, due to its antimicrobial activity. Therefore, films based on different polysaccharide and protein extracted mixtures were prepared with and without ZnO to get cost-effective bioactive wound dressings.

Compression molded biodegradable films based on poly(butylene succinate) (PBS) and poly(butylene adipate-co-terephthalate) (PBAT) at varying weights were prepared, and their relevant properties for packaging applications are here reported. The melt rheology of the blends was first studied, and the binary PBS/PBAT blends exhibited marked shear thinning and complex thermoreological behavior, due to the formation of a co-continuous morphology in the 50 wt% blend. The films were characterized by infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), mechanical tensile tests, scanning electron microscopy (SEM), and oxygen and water vapor permeability. PBS crystallization was inhibited in the blends with higher contents of PBAT, and FTIR and SEM analysis suggested that limited interactions occur between the two polymer phases. The films showed increasing stiffness as the PBS percentage increased, further, a sharp decrease in elongation at break was noticed for the films containing percentages of PBS greater than 25 wt%. Gas permeability decreased with increasing PBS content, indicating that the barrier properties of PBS can be tuned by blending with PBAT. The results obtained point out that the blend containing 25 wt% PBS is a good compromise between elastic modulus (135 MPa) and deformation at break (390%) values. Overall, PBS/PBAT blends represent an alternative for packaging films, as they combine biodegradability, good barrier properties and reasonable mechanical behavior.

Compression molded biodegradable films based on poly(butylene succinate) (PBS) and poly(butylene adipate-co-terephthalate) (PBAT) at varying weights were prepared, and their relevant properties for packaging applications are here reported. The melt rheology of the blends was first studied, and the binary PBS/PBAT blends exhibited marked shear thinning and complex thermoreological behavior, due to the formation of a co-continuous morphology in the 50 wt% blend. The films were characterized by infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), mechanical tensile tests, scanning electron microscopy (SEM), and oxygen and water vapor permeability. PBS crystallization was inhibited in the blends with higher contents of PBAT, and FTIR and SEM analysis suggested that limited interactions occur between the two polymer phases. The films showed increasing stiffness as the PBS percentage increased; further, a sharp decrease in elongation at break was noticed for the films containing percentages of PBS greater than 25 wt%. Gas permeability decreased with increasing PBS content, indicating that the barrier properties of PBS can be tuned by blending with PBAT. The results obtained point out that the blend containing 25 wt% PBS is a good compromise between elastic modulus (135 MPa) and deformation at break (390%) values. Overall, PBS/PBAT blends represent an alternative for packaging films, as they combine biodegradability, good barrier properties and reasonable mechanical behavior.

Background The organic extracts (OEs) of Dittrichia viscosa, a ruderal plant common in the Mediterranean regions, proved to have herbicidal properties. In order to improve OE effectiveness and to develop novel eco-friendly bioherbicidal products, different amounts of OE were included in poly(butylene succinate)- and polycaprolactone-based films (PBS and PCL, respectively). Particular attention was given to the study of interactions between the polymers and OEs, with a deep spotlight concerning the influence of OEs on structural, morphological and thermal properties of both polymers, in order to assess the OE releasing kinetics from the matrices and its tuned herbicidal action against seeds. Results The bioassays carried out on Lepidium sativum and Phelipanche ramosa seeds evidenced a more controlled and effective OE release by PBS than PCL, and a longer lasting efficacy by the polymers with a higher OE content. The chemical-physical analyses were performed on films before and after biological assays. The thermogravimetric analysis confirmed that OE was a thermal stabilizer of the polymer; the presence of OE and polymer separated degradative kinetics suggested that only a partial and functional miscibility between polymers and OE occurred. The morphological analysis confirmed the good OE dispersion between PBS and PCL molecular chains. Infrared spectroscopy highlighted the enhanced hydrolysed structure of the doped polymers after the bioassays. These outcomes well matched the quantitative information outlined by release kinetics. Discussion The use of biodegradable polymers allows the effectiveness and tuning of the release of the formulated bioactive compounds to be improved. The easy-to-obtain and easy-to-formulate OE could become a suitable and environmentally friendly instrument in weed management programmes.

In this work, α−costic acid (α-CA), a metabolite coming from a perennial autochthon shrub Dittrichia viscose, was used as natural additive of polylactic acid (PLA), a biodegradable thermoplastic polymer, in order to modulate its chemico-physical properties, for the achievement of a wholly biobased packaging system. It’s the first time that α−costic acid is exploited for this appealing and novel application. The investigations performed on PLA/α-CA films, evidenced strong physical interaction occurring between the polymer and α-CA, as confirmed by NMR and FTIR-ATR analyses; SEM micrographs showed a good embedding of α-CA particles inside PLA polymer matrix; GPC analysis highlighted a slight hydrolysis of polymer matrix clearly evidenced in mechanical properties. DSC analysis underlined the significant decreasing of Tg, associated with the increase of PLA chain mobility. TGA thermograms evidenced one broad degradation profile of PLA/α-CA system, accounting for the weighty physical interaction occurring between the polar groups of both polymer and plasticizer. Finally, PLA surface wettability notably enhanced by the inclusion of α-CA polar groups. In conclusion, α-CA can be considered as a promising plasticizer of PLA and a worthy modifier of its overall properties.

In this study, chitosan (C) tripolyphosphate (T) sub-micro particles containing ungeremine (CTUn), an alkaloid particularly active against Penicillium roqueforti, a fungus responsible of the bakery products deterioration, were prepared through external gelation crosslinking process. The particles were included in a thermoplastic starch based polymer Mater-Bi (MBi), and MBi/CTUn bioactive biocomposites were obtained. The films showed bioactivity against P. roqueforti. In particular, the bioassays were performed on films with different concentration of CTUn and at different pH values. CTUn particles influenced MBi crystallization (DSC analysis) and promoted thermal degradation of MBi starch component (TGA). Morphological analysis confirmed even distribution of sub-micro particles into the polymeric matrix. Water permeability slightly increased, as expected, whereas oxygen permeability decreased. Tensile tests showed CTUN sub-microparticles improved rigidity and tensile strength of the films at the expense of ductility. Finally, MBi/CTUn biocomposites evidenced interesting performances potentially exploitable in bioactive bakery based food packaging materials.

A pectin coated dehydrated apple snack containing ≥9 log colony forming units/20 g portion of the probiotic Lactobacillus paracasei IMPC2.1, was developed. The strain was incorporated into the apple slices using vacuum impregnation (IP1) or soaking/stirring (IP2); apple slices were then coated with citrus pectin and dehydrated at 4 °C for 14 days. Microbial application led to colonization of the apple surface, as seen using scanning electron microscope images, and all probiotic products showed comparable radical scavenging activity and total phenol content. IP2 led to better bacterial survival during 30 days storage at 4 °C and color parameters comparable to the fresh apple. The simulated gastro-intestinal (GI) digestion suggested the ability of the strain to survive the digestive process. This inclusion/coating/dehydration process led to a probiotic snack, which could successfully deliver bacterial cells in a viable form to the GI tract.

Ulomoides dermestoides (UL) are macroinvertebrates insects belonging to Tenebrionidae Coleopteran family. They were used to hasten, in five days, the biodegradation-mineralization of thermoplastic starch (TPS)-poly(lactic acid) (PLA) films, otherwise biodegradable under composting conditions. After the contact of TPS-PLA film with UL for five days, TPS was metabolized and PLA was hydrolysed, as evidenced by decreasing of hydroxyl and carbonyl group peaks intensity by FTIR spectra, increasing of 13% of PLA crystallinity by DSC thermograms, reduction of PLA and TPS thermal stability by TGA analysis; faecal residues evidenced two glass transition temperature T

Background Weed control represents a major issue in plant cultivation in containers. Manual weed control is very expensive and the use of chemical herbicide or plastic mulch films has a large environmental impact. The aim of this study was to test the efficacy of an experimental biodegradable chitosan-based mulching spray in controlling weed growth in containers. This research also studied the effect of this mulch on the growth of Viburnum lucidum Mill. plants to test for possible phytotoxic effects. Results The study compared a total of six treatments derived from three types of weed control (no weed control; herbicide, oxadiazon; mulching spray) applied in containers either filled only with the sterile substrate or filled with the sterile substrate and then artificially inoculated with seeds of the weed species [Sonchus asper (L.) Hill subsp. asper and Epilobium montanum L.]. The mulch controlled the weeds effectively for more than 2 months after its application even under severe weed infestation. The mulching spray controlled the emergence of S. asper more efficiently than E. montanum plants, probably because the latter has a stronger capacity to penetrate the mulch film during emergence. Conclusions Three months after its application, the mulch started to degrade and this allowed some weeds to emerge in the containers, but, in general, the mulch performed better than the herbicide. The chitosan-based mulch did not have any negative effective on the growth of V. lucidum plants.

In this study, chitosan based microbeads containing Ungeremine, an antimicrobial alkaloid particularly active against Penicillium roqueforti, a filamentous fungus responsible of the bakery products deterioration, were prepared by external gelation by using sodium tripolyphosphate (TPP) as crosslinking agent. The stability of the beads, as well as the loading efficiency of the bioactive molecule, were assessed at different pH and TPP concentrations resulting particularly enhanced at low pH. All the microbeads evidenced antimicrobial activity against Penicillium roqueforti. The release kinetics of Ungeremine was tailored by opportunely modulating pH and TPP concentrations. Morphological analysis evidenced the improvement of the structural crosslinking density of microbeads including Ungeremine and spectroscopic analysis emphasized the active participation of Ungeremine to the crosslinking process occurring between chitosan and TPP. Finally, thermogravimetric analysis confirmed the increasing of free volume in three-dimensional networks and their liability to thermal degradation.

There is significant potential for industrial use of renewables for a wide range of materials demanded by society. Plants, trees and algae are increasingly attracting attention as sustainable sources for functionalised and polymerizable building blocks. In particular, the outer bark of the birch tree (Betula pendula) is a side stream of the forestry industry with so far very little utilisation besides energy recovery. It is composed of a macromolecular network, suberin, that could provide a renewable, low cost and competitive resource. Within raw suberin is the potentially very useful multifunctional extract cis-9,10-epoxy-18-hydroxyoctadecanoic acid (CHA). Our drive has been to develop a green and sustainable synthetic strategy to CHA-based polyesters, by exploiting supercritical carbon dioxide (scCO2) as a reaction medium and leveraging the regio- and chemo-selective properties of the biocatalyst Novozym 435 (Lipase B). Low temperature (35–55 °C) polycondensation in scCO2 shows significant advantages compared to traditional polymerisation methods leading to reasonably high molecular weight polyesters. The mild synthetic conditions also preserve the valuable epoxy groups of the CHA which we show can be exploited by post-polymerisation functionalisation to create sustainable resins for bio-renewable coatings.

This manuscript describes antifungal, structural, thermal and morphological properties of a novel, eco-friendly bioplastic film, based on poly(butylenesuccinate) and cavoxin, a chalcone phytopathogenic metabolite, isolated from cultures by the fungus Phoma cava and included inside the biodegradable polymeric matrix. The antagonistic activity of the film explored against two fungal food contaminants Penicilliumroqueforti and Aspergillusniger, highlighted that cavoxin was fungicide at MIC concentrations. The chemico-physical analysis were performed on films before and after antifungal activity. Thermal analysis evidenced both the higher thermal stability of poly(butylenesuccinate) and cavoxin blend and the sharp nucleating action of cavoxin on the polymer. Infrared spectroscopy highlighted the presence of physical interaction between the polar groups of the blend components, whereas gel permeation chromatography highlighted that the hydrolytic effect of cavoxin on poly(butylenesuccinate) was responsible for the diffusion and releasing of the biomolecule from the matrix and UV–Vis spectroscopy provided quantitative information of release kinetics. Finally, morphological analysis confirmed both the polymeric surface hydrolysis exerted by cavoxin, and the adhesion of fungal spores on films after contact occurred during the antifungal assay.

In this paper, lemon and fennel wastes were recovered and used as secondary-raw polysaccharide sources. These polysaccharides were exploited as natural plasticizers of sodium alginate (A) based films, in order to improve sodium alginate performances, limited by its fragility, extending its potential application in a cost effective and eco-friendly way. Different green processes, such as maceration (MAC), ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE), were carried out for obtaining high yield of lemon and fennel polysaccharides (LP and FP). Actually, HPAE-PAD and TLC analyses evidenced the presence of xyslose, galactose, glucose and rhamnose monomers and galacturonic acid, typical of polysaccharides like pectin and xyloglucan chains. These findings were confirmed by NMR and FTIR spectroscopic analyses. Moreovers, gel filtration chromatography assessed the high molecular weight of recovered polysaccharides, particularly of FP waste fraction. The extracted polysaccharides were used as eco-friendly and cost-effective plasticizers of sodium alginate films (AFP and ALP). DSC analysis evidenced a significant decreasing of glass transition temperature of the polymer, tensile tests showed an enlightened rising of elongation at break and TGA analysis showed a faster degradation kinetics of AFP and ALP films, as expected in a plasticized system.

One of the greatest problems in food packaging system is prevention of food from the mold contamination. In particular, in the bakery products Penicillium roqueforti (PR) is the main contaminator associated to the food deterioration. Food packaging systems are responsible to protect food substrate from physical damage, chemical and biological contaminations. In addition, packages are designed to preserve the food quality and safety, extending their shelf-life. However, finalized to enhance the food packaging performances recently, the attention of research and industrial partnerships is increasingly focused on bioactive packaging. Antimicrobial food packaging is based on the incorporation of natural bioactive metabolites into polymer or biopolymer matrices, acts to reduce, inhibit or hinder the growth of microorganisms able to develop not only in the food but also in the packaging material itself. In particular, some plants material showed antifungal activity with potential application in food packaging. In this respect, ungeremine (Un) is one of the most active plant metabolites against P.roqueforti. Ungeremine is a betaine type alkaloids isolated from Pancratium maritimim L., a well knows species of Amaryllidaceae collected on Egypt northern coasts. Ungeremine was also obtained from SeO2 oxidation of lycorine, the main Amaryllideacea alkaloids. In this study, chitosan (Ch) based sub-micro particles containing ungeremine were prepared by using sodium tripolyphosphate (TPP) and formulated into Mater-Bi (MBi) polymer matrix. The Ch_TPP_Un/MBi composites were obtained by compression molding. The bioassay result of the films evidenced their activity against P.roqueforti. In addition, determination of residual ungeremine into films after 72h inhibition showed that, depending on the different food substrate pH, the diverse releasing pattern of fungicide from the package system could be expected. The morphological analysis confirmed a homogeneous distribution of sub-micro particles into MaterBi polymer matrix. The tensile test analysis showed that sub-micro particles could significantly decrease the ductility and slight increase in the elastic modulus of the films. Finally, thermogravimetric analysis confirmed specific physical interaction between chitosan based sub-microparticles and the starch fraction of MBi which, in turn, resulted in a decrease of thermal stability of MBi starch segments.

One of the greatest problems in food packaging system is the prevention of food from the mold contamination. Indeed, food mold infestation is very dangerous for human health and also can considerably increase the financial cost. In particular, in the bakery products, Penicillium roqueforti and Aspergillus niger are the main contaminators. On the other hand, food packaging systems are responsible to protect food substrate from physical damage, chemical and biological contaminations. In addition, packages are designed to preserve the food quality and safety, extending their shelf-life. However, due to environmental impact of the conventional polymers recently, the attention of researchers and industrial sectors are mainly on bioactive packaging by using bio polymer based package system. Antimicrobial food packaging known as active packing is based on the incorporation of natural bioactive metabolites into the polymer or biopolymer matrices to reduce, inhibit or hinder the growth of microorganisms on the packaged food. In particular, some plants material showed antifungal activity with potential application in food packaging. This project assayed the inhibitory activity of 13 bacterial, fungal and plant metabolites against P.roqueforti and A.niger and selected the most active ones which were cavoxin, ungeremine and ?-costic acid. The potential application of those natural metabolites into bio packaging system was investigated by the formulation of those metabolites into the biopolymer matrix in order to obtain active packaging system to increase the quality of food packaging, the food shelf-life, and microbiological safety.

Cardoon seed oil (CO), derived from the nonedible Cynara cardunculus plant, growing in marginal and contaminated soils of Mediterranean regions, was successfully epoxidized (ECO) in a fed-batch modality. The cost-effective and environmentally friendly oils have been used as bioplasticizers of poly(lactic acid) (PLA), to improve the overall properties and broaden its industrial applications as a biodegradable packaging material. Hence, physical blends and films of PLA, containing 3% by weight of CO and ECO, were prepared by melt extrusion and compression molding, and the effect of the both bioplasticizers on structural, thermal, and mechanical properties of the obtained films was investigated. Cardoon oils induced the decreasing of glass transition temperature due to PLA free volume enhancement. This effect was particularly marked in PLA–ECO film. Thermal stability of PLA was meaningfully improved upon addition of the oils, and the mechanical properties made evident the increase of PLA ductility, particularly enhanced in the PLA–ECO system, where the polymeric matrix and the oil showed stronger physical interaction and improved phase compatibility, as also revealed by spectroscopic and morphological analyses. Therefore, the plasticization action exerted by very low concentrations of epoxidized cardoon oil efficiently overcomes PLA drawbacks, thus encouraging the feasibility of its use as a bioplastic for packaging material.

Cynara Cardunculus plant was used as source of seed oil. The epoxidized oil (ECO) and presscake waste fibers (CP) recovered from post-oil extraction, were recombined for developing PLA functional biocomposites, according to “zero waste” circular economy approach. Different compositions of PLA/CP and PLA/CP/ECO were prepared in form of platelets and investigated by thermal, morphological, structural and mechanical analyses. The poor interfacial adhesion between the hydrophobic PLA matrix and short, hydrophilic and randomly dispersed presscake fibers, well evidenced by morphological analysis, was responsible of PLA thermal degradation hastening, Tg decreasing and tensile properties dropping down, since no mechanical stress transfer occurred from the polymer to the dispersed phase. The inclusion of ECO slightly improved the above properties due to its mild compatibilizing action inducing a fairly tightening of the macromolecular structure. The recycling of CP waste fibers was effective in hastening the polymer biodegradation in common soil under environmental conditions. Indeed, biocomposites recovered after 90 days of soil burial tests evidenced morphological features typical of late stage PLA biodegradation, a drastic dropping down of molecular weights and a decreasing of PLA thermal stability. These experimental evidences, not detected in soil buried neat PLA, assessed that the inclusion of CP waste fibers inside PLA matrix, represented a valid route to promote a fast and easy PLA biodegradation if compared to the composting method commonly used, for which severe atmosphere conditions and specific microbial population are necessary.

Citrus pomace derived from the industrial processing of juice and essential oils mostly consists of pectin, cellulose, hemicellulose, and simple sugars. In this work, citrus pomace waste from an agricultural company in South Italy was used as source of pectin. The extraction conditions of the polysaccharide were optimized using a suitable combination of time and a concentration of a mild organic solvent, such as acetic acid, thus recovering high Mw pectin and bioactive molecules (flavonoids and polyphenols). The pectin was structurally (GPC, FTIR), morphologically (SEM), thermally (TGA/DTG), and mechanically characterized, while bioactive molecules were separated and the total phenolic content (TPC) and total flavonoids content (TFC) were evaluated. With the aim to develop novel biocomposite-based materials, the pectin extracted from citrus waste was reinforced with different amounts of lignocellulose fractions also recovered from citrus waste after polysaccharide extraction, according to a “zero waste” circular economy approach. The prepared biocomposites were morphologically and mechanically characterized to be used as biodegradable mulching systems for crop protection. Thus, the citrus waste biomass was recovered, fractionated into its main raw materials, and these were recombined to develop novel upgraded biocomposites for mulching applications, by means of a cost-effective and eco-sustainable approach.

The present paper reports on pectin based films modified with carboxymethyl cellulose intended for food packaging. The films are prepared by solvent-casting method with different carboxymethyl cellulose content and cross-linker concentration (Ca2+ ions) in the presence of glycerol as a plasticizer. FT-IR spectra of the prepared films propose that carboxyl group from pectin are mainly involved in interactions with CMC, whereas −OH groups are mainly involved in self-associated hydrogen bonding of neat polymers. Further, an addition of carboxymethyl cellulose improved mechanical properties compared to pure pectin films, while TGA analysis confirmed satisfying thermal stability regarding their potential application as packaging material. Finally, water vapor permeability values are in the range of 1.32 × 10−7 up to 2.03 × 10−7 g/m h Pa. The 24th Annual World Forum on Advanced Materials, Poznan, Poland, May 9–13, 2016

The aim of this study was the development of novel polysaccharide based films intended to be used as edible food packaging material. The films were prepared by solution casting method using highly methoxylated pectin (PEC) and poly(ethylene glycol) (PEG) of various molecular weights (400, 600 and 1000 gmol(-1)) in different ratios (5:1, 3:1 and 1:1). The film formation was supported by hydrogen bonding between PEC and PEG, which was evidenced by means of ATR-FTIR and NMR analysis. TGA revealed that generally PEG behaves like a pro-degrading agent for pectin, except in the case of PEC/PEG film with a ratio of 1:1. Furthermore, DSC thermograms indicated that PEG1000 exists as a separate phase in the pectin matrix while the formulations with PEG400 and PEG600 showed mainly amorphous morphology. The addition of PEG enhanced the plasticization of PEC films, as evidenced by progressive decreasing of the glass transition temperature values (T-g). The tensile test measurements showed that increasing concentration of PEG produced weaker and more flexibile films. Due to the increased molecular mobility, the pectin phase became more permeable to water vapor as the PEG concentration increased. The obtained results showed that the combination of both polymers resulted in interesting bio -inspired edible films with the potential to compete with commercially used synthetic package materials. This is the peer-reviewed version of the article: Šešlija, S., Nešić, A., Ružić, J., Kalagasidis Krušić, M., Veličković, S. J., Avolio, R., Santagata, G.,& Malinconico, M. (2018). Edible blend films of pectin and poly(ethylene glycol): Preparation and physico-chemical evaluation. Food HydrocolloidsElsevier Sci Ltd, Oxford., 77, 494-501. [https://doi.org/10.1016/j.foodhyd.2017.10.027] The published version: [https://cer.ihtm.bg.ac.rs/handle/123456789/2473]

Active packaging refers to packaging systems with active functions beyond the inert passive containment and protection of the product. It is commonly used with foods, as it helps extend shelf life, improve safety or sensory properties and maintain food quality [1]. Most diffused active packaging systems include the use of oxygen scavengers, carbon dioxide or ethylene emitters and scavengers, ethanol releaser, as well as antimicrobial and antioxidant agents. The active agent may be placed in the package with the food, within a small sachet or pad of permeable material, able to release volatile antimicrobial agents without allowing a direct contact with the food product. Incorporation of volatile active agents into polymers is a technological challenge, due to the need to avoid evaporation of the additive during melt processing of the polymer. Such challenge can be solved by incorporation of the volatile molecules within cyclodextrins (CD), as detailed in this contribution. Cyclodextrins are biocompatible, biodegradable cyclic oligosaccharides produced from a renewable natural material, starch [2]. Cyclodextrins can form inclusion complexes with various non-polar, aliphatic and aromatic compounds, including antibacterial molecules, whose release could enhance the quality of the packaged product and extend its shelf life [3]. In the research detailed below, b-CD was used as cage to include D-limonene (4-isopropenyl-1-methylcyclohexene), the major constituent in several citrus-derived essential oils, which is also a natural antimicrobial agent [4-6]. D-limonene is listed in the Code of Federal Regulations and generally recognized as safe flavoring agent and food preservative [7]. Its outstanding antimicrobial activities have already been tested with different species of food-related microorganisms, such as staphylococcus aureus, Listeria monocytogenes, Salmonella enterica, Saccharomyces bayanus [8, 9]. Unfortunately, D-limonene is susceptible to oxidative degradation, which directly results in its loss of activity [7, 10]. Moreover, similar to other volatile essential oils, limonene aroma could be easily released to the packaged food, thus contaminating it. In order to overcome to these drawbacks, D-limonene was included into CDs, and the inclusion complex CD-Lim thus obtained was dispersed into a biodegradable and bio-based polymer matrix, namely poly(butylene succinate) (PBS). PBS is a biodegradable and bio-based polyester, currently used for food packaging, and its use in this market area is expected to largely increase in the coming years [11]. The aim of this paper is to prepare a novel biodegradable polymeric-based system, as potential bioactive food packaging material, by dispersing CD-Lim inclusion complex into PBS polymeric matrix and to investigate the chemical-physical properties of the obtained blends.

Biodegradable polymer films based on polybutylene succinate (PBS) and polybutylene adipate terephthalate (PBAT) blends with varying weight ratios were prepared by extrusion and chill roll calendering. The films were characterized by infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), mechanical tensile tests, scanning electron microscopy (SEM), and rheology. In the blends with higher content of PBAT, PBS crystallization was inhibited. As for mechanical performance, increasing the PBS content in PBAT an increase in the stiffness and a decrease in the ductility of the blends is detected. Finally, rheological measurements evidence an increase in the viscosity of the blends with increasing the PBAT content.

Ungeremine is a betaine type alkaloid isolated from Pancratium maritimim L., 1 and thus could be synthesized by SeO2 oxidation of lycorine, which is the main Amaryllideacea alkaloid obtained in high yield from Sterbergia lutea Ker Gawl. a wild species coollected on the coasts Apulia region in South Italy. 2 Ungeremine have shown a very significant antifungal activity against Penicillium roqueforti,3 a filamentous fungus responsible of the bakery products deterioration. In this study, chitosan based microbeads containing ungeremine, were prepared by external gelation by using sodium tripolyphosphate (TPP) as crosslinking agent. The stability of the microbeads, as well as the loading efficiency of the antifungal metabolite were assessed at different pH and TPP concentrations and resulted particularly enhanced at low pH. All the microbeads evidenced antimicrobial activity against Penicillium roqueforti. The release kinetics of ungeremine was tailored by opportunely modulating pH and TPP concentrations. Morphological analysis evidenced the improvement of the structural cross linking density of microbeads including ungeremine and spectroscopic analysis emphasized the active participation of ungeremine to the crosslinking process occurring between chitosan and TPP. Finally, thermogravimetric analysis confirmed the increasing of free volume in threedimensional networks and their liability to thermal degradation.

In this paper, a novel and sustainable process for the fruit dehydration was described. Specifically, edible coatings based on pectin and honey were prepared and used as dehydrating and antimicrobial agents of cut fruit samples, in this way promoting the fruit preservation from irreversible deteriorative processes. Pectin-honey coating was tested on apple, cantaloupe melon, mango and pineapple. The analysis were performed also on uncoated dehydrated fruits (control). The coated fruit evidenced enhanced dehydration percentage, enriched polyphenol and vitamin C contents, improved antioxidant activity and volatile molecules profile. Moreover, the antimicrobial activity against Pseudomonas and Escherichia coli was assessed. Finally, morphological analysis performed on fruit fractured surface, highlighted the formation of a non-sticky and homogeneous thin layer. These outcomes suggested that the novel fruit dehydration process, performed by using pectin-honey coating, was able to both preserve the safety and quality of dehydrated fruits, and enhance their authenticity and naturalness.

Sargassum algae are brown free-floating seaweed found worldwide in temperate and tropical regions and provide shelter and food for many animal species. In recent years, their wide-spread presence has gone out of control, leaving dense clumps of rotting weeds and toxic waste along urban beaches. Nevertheless, this harmful brown seaweed is a valid source of sodium alginate (SA), a well-known biodegradable and biocompatible polysaccharide, widely used in food, pharmaceutical and biomedical applications due to its stabilizing and gelling properties. The aim of this paper was the extraction and chemico-physical characterization of sodium alginate from Sargassum seaweeds wastes by using unconventional ultrasound method.

In this study, pectin based films including different amounts of sodium alginate were prepared by casting method. All the films, with and without polyglycerol as plasticizer, were crosslinked with zinc ions in order to extend their potential functionality. The development of junction points, occurring during the crosslinking process with zinc ions, induced the increasing of free volume with following changing in chemico-physical properties of films. The inclusion of alginate in pectin based formulations improved the strength of zinc ions crosslinking network, whereas the addition of polyglycerol significantly improved mechanical performance. Finally, zinc-crosslinked films evidenced antimicrobial activity against the most common exploited pathogens: Staphylococcus Aureus, Escherichia Coli and Candida Albicans. These results suggest that zinc-crosslinked based films can be exploitable as novel bio-active biomaterials for protection and disinfection of medical devices. (C) 2016 Elsevier Ltd. All rights reserved.

Agricultural activities need plastics for many applications such as films for soil mulching and pots for plants transplanting. The use of plastic products, made of fossil raw materials, such as polystyrene, polyethylene, and polypropylene results in huge quantities of plastic wastes to be disposed of. In the past two decades, the growing environmental awareness strongly encouraged researchers and industries toward the use of biodegradable polymers for solving the plastic waste problem. Researchers have made strong efforts to identify new biopolymers coming from renewable sources as valid ecosustainable alternatives to petroleum based plastic commodities. The main research results and current applications concerning the biodegradable plastics in agriculture, such as thermo-extruded Mater-Bi and sprayable water-born polysaccharides based coatings, are described in this chapter. A lineup of biopolymers coming from raw and renewable sources, such as polysaccharides, are reported; the intrinsic chemico-physical properties of polysaccharides, responsible for the realization of dry water stable hydrogels, suitable for the formation of both soil mulching coatings and transplanting biopots, are investigated. A description of the natural additives, fillers and cellulosic fibers included in the polymeric matrices, able to enhance the mechanical performance of coatings and pots is provided, together with the outputs in the specific applications.

Pectin is a promising candidate to be employed as binder for manufacturing pellets for crayfish feeding. In this study, the gelling properties of different types of pectin and their effects on Cherax quadricarinatus performances have been analysed. Pectins with different degree of esterification from apple and citrus were screened to select those with the best gelling properties to be employed in pellet manufacturing. Three pectins were selected: low esterification degree apple pectin (LEAP), low esterification citrus pectin (LECP) and high esterification degree apple pectin (HEAP). Scanning electron microscopy analysis, nutrient leaching and water uptake indicated that LEAP showed the best aggregating properties, followed by LECP and HEAP pellets. Cherax quadricarinatus performances were affected by the pectin type, with redclaw fed LEAP pellets showing the highest (P

In this paper, physico-chemical, mechanical and antimicrobial properties of hydrogels based on alginate/N-succinylchitosan blends crosslinked by calcium or zinc ions containing cellulose microfibers were investigated and discussed. With respect to plain alginate hydrogels, the addition of N-succinylchitosan significantly improved properties such as swelling degree and stability in saline solution. The water vapour transmission rate confirmed that all the hydrogels were able to assure a moist wound environment. Morphological analysis showed a good embedding of fibres within the zinc crosslinked hydrogels. In addition, zinc-crosslinked hydrogels evidenced antimicrobial activity against two common skin pathogenic bacteria, Staphylococcus aureus and Escherichia coli. Cytotoxicity assays proved that the amount of zinc released is slightly over the toxic level. Overall, the characteristics of the zinc-crosslinked hydrogels showed their potential interest as materials for wound dressing.

Polymers which are biodegradable in vivo and in the environment, especially those of natural origin, are perceived by the public as a valuable alternative to non biodegradable plastics. However, biodegradability, although important, cannot be the only driving force for the market acceptance of so called "green" plastics and chemicals. The applications of traditional oil-based plastics and plastic additives span from commodities to specialties, due to their performances and sometimes affordable costs. Can naturally derived polymers and additives face the challenge of petro-plastics and chemicals? Can we use the experience acquired in the so-called "plastic age" to tailor the performances of natural polymers and polymer additives for a demanding technological world? Several experiences on the processing of natural biodegradable polymers and on their formulation with additives coming from natural sources to obtain modified plastics, blends or composites are reviewed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.