Rosmarinic Acid and Ulvan from Terrestrial and Marine Sources in Anti-Microbial Bionanosystems and Biomaterials

In order to increase their sustainability, antimicrobial renewable molecules are fundamental additions to consumer goods. Rosmarinic acid is extracted from several terrestrial plants and represents an effective anti-microbial agent. Ulvan, extracted from algae, is an anti-microbial polysaccharide. The present review is dedicated to discussing the sources and the extraction methodologies for obtaining rosmarinic acid and ulvan. Moreover, the preparation of bioanosystems, integrating the two molecules with organic or inorganic substrates, are reviewed as methodologies to increase their effectiveness and stability. Finally, the possibility of preparing functional biomaterials and anti-microbial final products is discussed, considering scientific literature. The performed analysis indicated that the production of both molecules is not yet performed with mature industrial technologies. Nevertheless, both molecules could potentially be used in the packaging, biomedical, pharmaceutical, cosmetic, sanitary and personal care sectors, despite some research being required for developing functional materials with specific properties to pave the way for many more applications.

Effect of Different Inorganic Substrates on Growth Performance of African Catfish (Clarias gariepinus, Burchell 1822) and Lettuce (Lactuca sativa L.)

Lettuce (Lactuca sativa L.) and African catfish (Clarias gariepinus) were preferred to grow in aquaponics due to their high and fast productivity growth. However, limited research was conducted on the impact on different inorganic substrates’ growth performance in aquaponics. In this study, lettuce’s growth performance was determined in four different kinds of inorganic substrates in Nutrient Film Technique (NFT) aquaponics by measuring final weight, daily growth rate, stem diameter, plant and root lengths, leaf number per plant and shoot/root ratio. Polyester fiber, rock wool, zeolite, and gravel were used as inorganic substrate materials. A constant flow rate of 0.3 L/min was maintained using with a submersible pump motor. At the end of the study, the African catfish’s feed conversion ratio was estimated to be 0.66, while the specific growth rate (SGR) was 2.3%. Total lettuce yields for polyester fiber, rock wool, zeolite and gravel were obtained as 5.072,22 kg/m2, 4.934,03 kg/m2, 6.067 kg/m2, and 5.382,64 kg/m2 respectively. There were statistically significant differences for daily growth rate between the inorganic substrates that the significantly highest values were recorded in the zeolite. The results revealed that initial plant length and shoot/root ratio were the significant factors on the growth performance for lettuce in aquaponic system tested. The best lettuce yield performance was observed in zeolite substrate but, economically available option was found as gravel for hydroponic troughs.

Study of the Bond Capacity of FRCM- and SRG-Masonry Joints

Fiber-reinforced cementitious matrix (FRCM) and steel-reinforced grout (SRG) have been increasingly applied as externally bonded reinforcement to masonry members in the last few years. Unlike fiber-reinforced polymer (FRP), FRCM and SRG have good performance when exposed to (relatively) high temperature and good compatibility with inorganic substrates, and they can be applied to wet surfaces and at (reasonably) low temperatures. Although numerous studies investigated the mechanical properties and bond performance of various FRCM and SRG, new composites have been developed recently, and their performance still needs to be assessed. In this study, the bond behavior of three FRCM composites and one SRG composite applied to a masonry substrate is investigated. Sixteen single-lap direct shear tests (four tests for each composite) are performed. The FRCM studied comprised one layer of carbon, PBO (polyparaphenylene benzobisoxazole), or alkali-resistant (AR)-glass bidirectional textile embedded within two cement-based matrices. The SRG composite comprised one layer of a unidirectional stainless-steel cord textile embedded within a lime-based matrix. The results show a peculiar bond behavior and failure mode for each composite. Based on these results, the behavior of the carbon and PBO FRCM is modeled solving the bond differential equation with a trilinear cohesive material law (CML).

Microfluidic devices based on textile threads for analytical applications: state of the art and perspectives

Microfluidic devices based on textile threads have interesting advantages when compared to systems made with traditional materials, such as polymers and inorganic substrates (especially silicon and glass). One of these...

The use of sewage sludge and diatomite as growing medium in scots pine (Pinus sylvestris L.) seedling production and evaluation of its land performance

Although several organic and inorganic substrates are added to growing media for improving its physical and chemical characteristics, the need for search of new materials and/or mixtures that reduces the high-priced peat content in substrates is still interesting. This study evaluated the feasibility of reducing the peat content in substrates by replacing it with different amounts of diatomite and sewage sludge for Scots pine seedling (Pinus sylvestris L.) growth and their land performance. In order to evaluate the feasibility of reducing the peat content in substrates by replacing it with different amounts of diatomite and sewage sludge, an experiment was carried out in a temperature-controlled greenhouse under natural light. To evaluate the land performance of Scots pine seedlings grown in different substrates, a trial was established between the years 2013-2017 in Sarıkamış, Kars (NE Anatolia). Sewage sludge application, due to its high organic matter and macro and micronutrient content, has improved the composition of the rhizosphere, thereby resulting in growth acceleration. As a result of the evaluations made in terms of both seedling morphological characteristics and land performance; the best performance was determined in the 9^th (50%P+50%SS) and 3^rd (75%SS+25%DE) mixtures.

Laser-induced graphitization of polydopamine leads to enhanced mechanical performance while preserving multifunctionality

Polydopamine (PDA) is a simple and versatile conformal coating material that has been proposed for a variety of uses; however in practice its performance is often hindered by poor mechanical properties and high roughness. Here, we show that blue-diode laser annealing dramatically improves mechanical performance and reduces roughness of PDA coatings. Laser-annealed PDA (LAPDA) was shown to be >100-fold more scratch resistant than pristine PDA and even better than hard inorganic substrates, which we attribute to partial graphitization and covalent coupling between PDA subunits during annealing. Moreover, laser annealing provides these benefits while preserving other attractive properties of PDA, as demonstrated by the superior biofouling resistance of antifouling polymer-grafted LAPDA compared to PDA modified with the same polymer. Our work suggests that laser annealing may allow the use of PDA in mechanically demanding applications previously considered inaccessible, without sacrificing the functional versatility that is so characteristic of PDA.

Electrosynthetized copper based nanoantimicrobials for the inhibition of biofilms

<ol> <li><strong>S. I. Hossain<sup>1,3,*</sup>, M. C. Sportelli<sup>1,2,3</sup>, R. A. Picca<sup>1,3</sup>,</strong> <strong>N. Ditaranto<sup> 1,3</sup>, N. Cioffi<sup>1,3</sup></strong></li> </ol> <p><sup>1</sup>Dipartimento di Chimica, Università degli Studi di Bari “Aldo Moro”, Bari, Italy; <sup>2</sup>CNR, Istituto di Fotonica e Nanotecnologie UOS, Bari, Italy;       <sup>3</sup>CSGI (Center for Colloid and Surface Science) c/o Dept. Chemistry, via Orabona 4, 70125 Bari, Italy.</p> <p> </p> <p>Copper nanoparticles (CuNPs) are considered as potential antimicrobial agents due to their improved stability and safety, and longer active period than that of organic nanomaterials, with multi-targeted mechanism of action [1]. Nevertheless, metal NPs can suffer from agglomeration, reducing their antibacterial activity [2]. Cu incorporation in inorganic substrates such as metal oxides or montmorillonite (MMT) plays an important role due to the possibilities of creating an antibacterial nanomaterial with slow release of Cu species in order to obtain a prolonged antibacterial activity. Therefore, CuNPs were synthesized via a rapid electrochemical method using the inorganic micro-powders as carrier. Characterization studies on the nanocomposite were done by Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The as-prepared Cu-based nanocomposites could be employed for inhibiting the growth of biofilms.</p> <p><strong>References</strong></p> <ol> <li>Nanotechnology 25, (2014), 135101</li> <li>ACS Appl. Mater. Interfaces 4, (2012), 178–184</li> </ol> <p><strong>Acknowledgements</strong></p> <p>"Financial support is acknowledged from European Union’s 2020 research <br /> and innovation program under the Marie Sklodowska-Curie Grant <br /> Agreement No. 813439."</p>

Advanced ceramics and relevant polymers for environmental and biomedical applications

Ceramics result from combinations and structural arrangements of inorganic substrates for metals and nonmetals. They bind covalently forming ceramic with distinctive properties. Advanced ceramics can be applied in progressive applications. They comprise advanced heat engines for communication and energy transmission. They are developing among the required materials for advanced technologies. Advanced ceramics are getting along modern technological applications. Researches and studies focus on enhancing and optimizing the desired properties. They are trying to overcome some disadvantages such as brittleness and poor mechanical properties. Polymers play an important role in either forming ceramics or blending with them to form efficient composites. Some polymers are classified as inorganic and organic materials such as polysilazanes. They consist of silicon, nitrogen, hydrogen and carbon in certain cases. Polysilazanes act as precursors to SiO2, Si3N4 and SiC ceramics. Perceramic polymers are pyrolyzed polymeric materials in an inert atmosphere producing ceramic materials. Ceramics can be applied in the absence or the presence of polymers in various fields. They comprise wear related, environmental and electrical applications as well. Bioceramics and biopolymers were used as implants in orthopaedics. Zirconia based ceramics act as successful materials to be applied in dental applications.

Spatial distribution and substrate preferences of the non-indigenous amphipod Gammarus roeselii Gervais, 1835

Gammarus roeselii is one of the successful non-indigenous species recently established in the Ticino River basin (Northern Italy). G. roeselii is not usually considered to be a real threat to native gammarids because no evidence has been reported so far on its effects on biodiversity and habitats. In this study, we assessed the spatial distribution of G. roeselii in the secondary hydrographic system of the southern part of the sub-lacustrine Ticino River basin and examined substrate preferences on the basis of laboratory experiments. We found that G. roeselii is well established in this area, occurring in almost all the seminatural streams, reaching high densities. Furthermore, we found that this species has a preference for two distinct types of substrate: empty shells of the bivalve Corbicula fluminea, which provide a suitable shelter for the introduced amphipod, and aquatic plants, which provide food resources. Conversely, preference for inorganic substrates, such as stones, was lower. In addition, the results indicate that G. roeselii easily inhabits the water column. The high adaptability of G. roeselii, combined with its capacity to exploit different niches and its swimming ability, are ecological characteristics that can favour its colonisation of new areas.