Natural Biocides to Prevent the Microbial Growth On Cultural Heritage

Many historic, cultural and artistic objects and buildings are made of stone. Like all materials, stone is subject to inexorable deterioration. Along with chemical and physical weathering factors, microbial growth plays an important role in this process. Stones type and local climatic differences have a great impact on the biodeterioration process and their outcomes. Microbial metabolism results in deteriorating agents such as organic and inorganic acid, chelating agents, enzymes and extracellular polymeric substances (EPS) causing e.g. biocorrosion and biomineralization; furthermore phototropic and heterotropic microorganism (ex. Firmicutes and fungi) are able to penetrate into stone mineral [1,2,3]. In addition to structural damage, rock biofilms cause aesthetic damage. In general the biocides used to prevent the growth of microbes are mostly based by using chemical methods, but they show a restricted efficiency and can cause discolorations and severe damages to the cultural heritage and ,also, they affect higher organisms including humans. Recently, the biotechnology and the applied microbiology (the use of antagonistic organisms or their metabolites products against the biodeteriorating agents) offers a wide range of new procedures for the cleaning and conservation of the artistic substrata [4-9]. The case of the study regards two historical bridges: the “San Vito Bridge” located in Potenza and “Della Vecchia Bridge” located in Campomaggiore, a little village near Potenza. The bacteria isolated belong to a wide variety of phylogenetic group being closely related to species of 10 genera within the Proteobacteria, the Firmicutes and the Actinobacteria; the number of fungi was slightly lower than those of bacteria. The fungi isolated on two bridges belong to Aspergillus, Penicillium and Stemphylium genera. In this work secondary metabolites of Burkholderia gladioli pv. agaricicola (Bga) ICMP 11096 strain and glycoalkaloids derived from Solanacee extracts, were used against bacteria and fungi isolated. Results show that all secondary metabolites inhibited in vitro and in vivo the growth of these colonising confirming that the application of biopesticides will be is a promising alternative to synthetic pesticides over traditional technologies. In fact, the use of these natural substances consents a more homogeneous removal of the surface deposits without compromising the substrata structure and the preservation of patina noble ; in addition, bio-cleaning has proven to be more selective than chemicals

Use of plant growth promoting bacteria (PGDB) for promoting tomato growth and its evaluation as biological control agent.

The plant growth promoting effect of some bacteria usable to control plant diseases has a potential for resolving technical problems of plant production. The effects of Burkholderia gladioli pv. agaricicola ICMP11096 on development of tomato seedlings development and control of their infection by Fusarium oxysporum and Sclerotinia sclerotiorum were evaluated in the present study. Bacterized plants showed a higher shoot and root weight and a more extended root system in terms of total length and root density than non-bacterized plants. The bacter-izing treatments gave rise to significant reduction of disease symptoms such as leaf wilting induced by F. oxysporum infection and/or root ne-crosis and leaf yellowing by S. sclerotiorum. The potential use of Burkholderia gladioli pv. agaricicola ICMP11096 in biocontrol of fungal patho-gens and to enhance seedling growth parameters is underlined as a tool to achieve a high commercial quality of nursery tomato plants

Engineered Extracellular Vesicles From Human Periodontal-Ligament Stem Cells Increase VEGF/VEGFR2 Expression During Bone Regeneration

Bone regeneration represents still a challenge, in particular for calvarium defects. Recently, the development of biomaterials with the addiction of stem cells is giving promising results for the treatment of bone defects. In particular, it was demonstrated that scaffolds enriched with mesenchymal stem cells (MSCs) and/or their derivatives, such as conditioned medium (CM) and extracellular vesicles (EVs), may improve bone regeneration. Moreover, given the deep link between osteogenesis and angiogenesis, a successful approach must also take into consideration the development of vascularization. In this work we evaluated the bone regeneration capacity of a collagen membrane (3D-COL) enriched with human periodontal-ligament stem cells (hPDLSCs) and CM or EVs or EVs engineered with polyethylenimine (PEI-EVs) in rats subjected to a calvarial defect. We evaluated also their capacity to induce angiogenic factors. At first, in vitro results showed an increased expression of osteogenic markers in hPDLSCs cultured with the 3D-COL and PEI-EVs, associated also with the increased protein levels of Vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2). The increased expression of these proteins was confirmed also in vivo in rats implanted with the 3D-COL enriched with hPDLSCs and PEI-EVs. Moreover, histological examination evidenced in this group of rats the activation of bone regeneration and of the vascularization process. Also MicroCT imaging with morphometric analysis confirmed in rats transplanted with 3D-COL enriched with hPDLSCs and PEI-EVs an important regenerative process and a better integration level. All together, these results evidenced that the 3D-COL enriched with hPDLSCs and PEI-EVs may promote bone regeneration of calvaria defects, associated also with an increased vascularization

Potato leaf extract and its component, alpha-solanine, exert similar impacts on development and oxidative stress in galleria mellonella L.

WOS: 000340608000003PubMed: 25041927Plants synthesize a broad range of secondary metabolites that act as natural defenses against plant pathogens and herbivores. Among these, potato plants produce glycoalkaloids (GAs). In this study, we analyzed the effects of the dried extract of fresh potato leaves (EPL) on the biological parameters of the lepidopteran, Galleria mellonella (L.) and compared its activity to one of the main EPL components, the GA alpha-solanine. Wax moth larvae were reared from first instar on a diet supplemented with three concentrations of EPL or alpha-solanine. Both EPL and alpha-solanine affected survivorship, fecundity, and fertility of G. mellonella to approximately the same extent. We evaluated the effect of EPL and alpha-solanine on oxidative stress in midgut and fat body by measuring malondialdehyde (MDA) and protein carbonyl (PCO) contents, both biomarkers of oxidative damage. We evaluated glutathione S-transferase (GST) activity, a detoxifying enzyme acting in prevention of oxidative damage. EPL and alpha-solanine altered MDA and PCO concentrations and GST activity in fat body and midgut. We infer that the influence of EPL on G. mellonella is not enhanced by synergistic effects of the totality of potato leaf components compared to alpha-solanine alone. (C) 2014 Wiley Periodicals, Inc

Insecticidal properties of Solanum nigrum and Armoracia rusticana extracts on reproduction and development of Drosophila melanogaster

Plant-derived substances, because of high biological activity, arouse interest of many scientists. Thus, plant extracts and pure substances are intensively studied on various insects as potential insecticides. In such studies, D. melanogaster is one of the most important model organisms. In our studies, we analysed the contents of two plant extracts and tested the activity of their main components against fruit flies and compared observed effects to effects caused by crude extracts. Then, we assessed the development of the next, unexposed generation. The chemical analysis of extracts revealed the presence of numerous glycoalkaloids and glucosinolates in Solanum nigrum and Armoracia rusticana extracts. These extracts, as well as their main components, revealed lethal and sublethal effects, such as the altered developmental time of various life stages and malformations of imagoes. Interestingly, the results for the extracts and pure main compounds often varied. Some of the results were also observed in the unexposed generation. These results confirm that the tested plants produce a range of substances with potential insecticidal effects. The different effects of extracts and pure main components suggest the presence of minor compounds, which should be tested as insecticides

A review of bioinsecticidal activity of solanaceae alkaloids

Only a small percentage of insect species are pests. However, pest species cause significant losses in agricultural and forest crops, and many are vectors of diseases. Currently, many scientists are focused on developing new tools to control insect populations, including secondary plant metabolites, e.g., alkaloids, glycoalkaloids, terpenoids, organic acids and alcohols, which show promise for use in plant protection. These compounds can affect insects at all levels of biological organization, but their action generally disturbs cellular and physiological processes, e.g., by altering redox balance, hormonal regulation, neuronal signalization or reproduction in exposed individuals. Secondary plant metabolites cause toxic effects that can be observed at both lethal and sublethal levels, but the most important effect is repellence. Plants from the Solanaceae family, which contains numerous economically and ecologically important species, produce various substances that affect insects belonging to most orders, particularly herbivorous insects and other pests. Many compounds possess insecticidal properties, but they are also classified as molluscides, acaricides, nematocides, fungicides and bactericides. In this paper, we present data on the sublethal and lethal toxicity caused by pure metabolites and crude extracts obtained from Solanaceae plants. Pure substances as well as water and/or alcohol extracts cause lethal and sublethal effects in insects, which is important from the economical point of view. We discuss the results of our study and their relevance to plant protection and management

Solanum tuberosum and Lycopersicon esculentum Leaf Extracts and Single Metabolites Affect Development and Reproduction of Drosophila melanogaster.

Glycoalkaloids are secondary metabolites commonly found in Solanaceae plants. They have anti-bacterial, anti-fungal and insecticidal activities. In the present study we examine the effects of potato and tomato leaf extracts and their main components, the glycoalkaloids α-solanine, α-chaconine and α-tomatine, on development and reproduction of Drosophila melanogaster wild-type flies at different stages. Parental generation was exposed to five different concentrations of tested substances. The effects were examined also on the next, non-exposed generation. In the first (exposed) generation, addition of each extract reduced the number of organisms reaching the pupal and imaginal stages. Parent insects exposed to extracts and metabolites individually applied showed faster development. However, the effect was weaker in case of single metabolites than in case of exposure to extracts. An increase of developmental rate was also observed in the next, non-exposed generation. The imagoes of both generations exposed to extracts and pure metabolites showed some anomalies in body size and malformations, such as deformed wings and abdomens, smaller black abdominal zone. Our results further support the current idea that Solanaceae can be an impressive source of molecules, which could efficaciously be used in crop protection, as natural extract or in formulation of single pure metabolites in sustainable agriculture

Development of <i>D</i>. <i>melanogaster</i> fruitflies–effect of α-solanine.

<p>(a) exposed to α-solanine; (b) the next (non-exposed, F₁) generation.</p

Effect of <i>S</i>. <i>tuberosum</i> leaf extract, α-chaconine and α-solanine on parental (exposed) generation of <i>D</i>. <i>melanogaster</i>.

<p>Effect of <i>S</i>. <i>tuberosum</i> leaf extract, α-chaconine and α-solanine on parental (exposed) generation of <i>D</i>. <i>melanogaster</i>.</p