Development of a Chitosan-Based Film from Shellfish Waste for the Preservation of Various Cheese Types during Storage.

The global concern about the use of disposable plastics has fed the research on sustainable packaging for food products. Among the virtuous materials, chitosan emerges as a valid alternative to conventional polyethylene films because of its abundance in nature. In this work, a novel film for food wrapping was developed by exploiting shellfish waste according to a vision of circular economy. Compared to previous studies, here, novel ingredients, such as polyvinyl alcohol (PVA), fibroin, and essential oils, were used in a synergistic combination to functionally postpone cheese deterioration. The fermentative procedure applied for the obtainment of chitin contributes to filling the existing gap in the literature, since the majority of studies are based on the chemical pathways that dramatically impact the environment. After pretreatment, the shrimp shell waste (SSW) was fermented through two bacterial strains, namely Lactobacillus plantarum and Bacillus subtilis. A deacetylation step in an alkaline environment transformed chitin into chitosan, yielding 78.88 g/kg SWW. Four different film formulations were prepared, all containing chitosan with other ingredients added in order of decreasing complexity from the A to D groups. The novel films were tested with regard to their physico-mechanical and antioxidant properties, including the tensile strength (12.10-23.25 MPa), the elongation at break (27.91-46.12%), the hardness (52-71 Shore A), the film thickness (308-309 µm), and the radical scavenging activity (16.11-76.56%). The performance as a cling film was tested on two groups of cheese samples: the control (CTR), wrapped in conventional polyethylene (PE) film; treated (TRT), wrapped in the chitofilm formulation deemed best for its mechanical properties. The volatiles entrapped into the headspace were investigated by means of the SPME-GC technique. The results varied across soft, Camembert, and semi-hard cheeses, indicating a growing abundance of volatiles during the conservation of cheese. The bacterial growth trends for mesophilic, enterobacteriaceae, and lactic acid bacteria were expressed as the mean colony forming units (CFU)/mL for each type of cheese at different sampling times (day 2, day 8, and day 22): the highest load was quantified as 8.2 × 106 CFU/mL at day 22 in the CTR Camembert cheese. The TRT samples generally exhibited inhibitory activity comparable to or lower than that observed in the CTR samples. The sensory analysis revealed distinctions in cheese taste between the TRT and CTR groups.

Opuntia ficus indica cladode as fermentation feedstock for lactic acid production by Lactobacillus acidophilus LA 5.

Opuntia ficus-indica cladodes are by-products which contain high amounts of fibres, bioactive and functional compounds. Given their high annual productivity per hectare, cladodes represent a cheap and suitable substrate, usable for fermentation processes. We investigated their potential as a substrate for the growth and production of lactic acid from Lactobacillus acidophilus LA-5. A separate hydrolysis and fermentation was performed. The concentration of reducing sugars obtained after the dilute acid and enzymatic hydrolysis was 28.45 g/L. The lactobacillus count ranged from 6.03 to 8.1 log CFU/mL, whereas lactic acid yield and productivity were 0.63 g/g and 0.73 g/L h, respectively. The maximum lactic acid concentration was found to be 17.5 g/L. This study reports the possibility of using the O. ficus indica cladode for lactic acid production by LA-5 aiming to reduce costs for sustainable industrial production.

Natural Pigments Production and Their Application in Food, Health and Other Industries.

In addition to fulfilling their function of giving color, many natural pigments are known as interesting bioactive compounds with potential health benefits. These compounds have various applications. In recent times, in the food industry, there has been a spread of natural pigment application in many fields, such as pharmacology and toxicology, in the textile and printing industry and in the dairy and fish industry, with almost all major natural pigment classes being used in at least one sector of the food industry. In this scenario, the cost-effective benefits for the industry will be welcome, but they will be obscured by the benefits for people. Obtaining easily usable, non-toxic, eco-sustainable, cheap and biodegradable pigments represents the future in which researchers should invest.

Monitoring Cannabinoids and the Safety of the Trace Element Profile of Light Cannabis sativa L. from Different Varieties and Geographical Origin.

Non-intoxicating Cannabis sativa L. (i.e., hemp) is increasingly used for industrial, cosmetic and food applications. Despite the fact that the EU has not yet established a regulatory framework on hazardous compounds (i.e., toxic inorganic elements), the monitoring of cannabis products is of paramount importance to safeguard consumers, also in view of the species propensity to accumulate toxic metals from the environment. The aim of this work was to assess the compliance with Law n. 242/2016 and the safety of hemp inflorescences from different varieties and Italian regions by monitoring the main cannabinoids and trace elements. All samples complied with the Italian law due to a THC content <0.6% counterbalanced by high CBD levels. However, inflorescences grown in Apulia and Lombardy, and from Finola and Tiborzallasi varieties accumulated higher Cu, Co, Cr, Ni and Pb contents than products from other producing areas (i.e., Sicily and Latium) and varieties (i.e., Antal, Futura75, Kompolti and Carmagnola), being moreover above the limits set by the US Pharmacopeia. A principal component analysis confirmed that trace elements, including toxic metals, were mainly affected by the geographical origin more than the botanical variety. Overall, this study highlights the need to continuously monitor hemp products and establish the earliest related regulatory frameworks.

Titanium Surface Modification for Implantable Medical Devices with Anti-Bacterial Adhesion Properties.

Pure titanium and titanium alloys are widely used in dentistry and orthopedics. However, despite their outstanding mechanical and biological properties, implant failure mainly due to post-operative infection still remains a significant concern. The possibility to develop inherent antibacterial medical devices was here investigated by covalently inserting bioactive ammonium salts onto the surface of titanium metal substrates. Titanium discs have been functionalized with quaternary ammonium salts (QASs) and with oleic acid (OA), affording the Ti-AEMAC Ti-GTMAC, Ti-AUTEAB, and Ti-OA samples, which were characterized by ATR-FTIR and SEM-EDX analyses and investigated for the roughness and hydrophilic behavior. The chemical modifications were shown to deeply affect the surface properties of the metal substrates and, as a consequence, their bio-interaction. The bacterial adhesion tests against the Gram-negative Escherichia Coli and Gram-positive Staphylococcus aureus, at 1.5 and 24 h of bacterial contact, showed good anti-adhesion activity for Ti-AUTEAB and Ti-OA samples, containing a long alkyl chain between the silicon atom and the ammonium functionality. In particular, the Ti-AUTEAB sample showed inhibition of bacteria adhesion against Escherichia Coli of about one log with respect to the other samples, after 1.5 h. The results of this study highlight the importance of chemical functionalization in addressing the antimicrobial activity of metal surfaces and could open new perspectives in the development of inherent antibacterial medical devices.

Chemical Characterization, Antibacterial Activity, and Embryo Acute Toxicity of Rhus coriaria L. Genotype from Sicily (Italy).

This study reports a full characterization of the Sicilian sumac, Rhus coriaria L. This fruit represents a potential source of fiber (33.21 ± 1.02%) and unsaturated fatty acids, being the contents of linoleic and α-linolenic acids, 30.82 ± 1.21% and 1.85 ± 0.07%, respectively. In addition, the content of phenolic and total anthocyanin was 71.69 ± 1.23 mg/g as gallic acid equivalents, and 6.71 ± 0.12 mg/g as cyanidin-3-O-glucoside equivalents, respectively. The high content in mineral elements, consisting mainly of potassium, calcium, magnesium, and phosphorus, followed by aluminum, iron, sodium, boron, and zinc, was detected by inductively coupled plasma mass spectrometry (ICP-MS). Moreover, its antimicrobial activity was evaluated against multidrug resistant (MDR) microorganisms, represented by Escherichia coli and Klebsiella pneumoniae strains isolated from poultry. The activity of seven different sumac fruit extracts obtained using the following solvents-ethanol (SE), methanol (SM), acetone (SA), ethanol and water (SEW), methanol and water (SMW), acetone and water (SAW), water (SW)-was evaluated. The polyphenol profile of SM extract, which showed better activity, was analyzed by ultra-high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS). The major component identified was gallic acid, followed by quercetin, methyl digallate, pentagalloyl-hexoside, and kaempferol 3-O-glucoside. The non-toxicity of Sicilian R. coriaria was confirmed by testing the effect of the same extract on zebrafish embryos.

Chemical Characterization of Different Products from the Tunisian Opuntia ficus-indica (L.) Mill.

Various dried (by-)products from the Tunisian O. ficus-indica were elucidated for their proximate composition, fatty acid (FA) composition, inorganic elements, sugars, and polyphenols. Nopal and prickly pear peel and seeds were abundant in fiber (respectively, 28.39, 12.54, and 16.28%). Seeds had also high protein (17.34%) and may be source of an edible oil, due to lipids (9.65%) poor in saturated FAs (14.12%) and rich in linoleic acid (61.11%). Nopal and peel showed the highest levels of Mg (493.57 and 345.19 mg/100 g), K (6949.57 and 1820.83 mg/100 g), Mn (59.73 and 46.86 mg/Kg) and Fe (23.15 and 15.23 mg/Kg), while the fruit pulp predominantly constituted of sugars, glucose and arabinose being predominant (42.57 and 13.56 g/100 g). Total polyphenols widely varied among the Opuntia products (108.36-4785.36 mg GAE/100 g), being mainly represented by hydroxycinnamic and hydroxybenzoic acids, and flavonoids as well. In particular, peel may be revalorized for these valuable bioactives, including 4-hydroxybenzoic acid (484.95 mg/100 g), cinnamic acid (318.95 mg/100 g), rutin (818.94 mg/100 g), quercetin (605.28 mg/100 g), and several isorhamnetin and kaempferol glycosides. Overall, the Tunisian prickly pear cactus could encourage a sustainable production, an effective waste management, and may provide several benefits for human health, in accordance with the model of the Mediterranean diet.