Rita Pagiotti

Antimicrobial activities of various essential oils against foodborne pathogenic or spoilage moulds

The use of essential oils in the food industry, as natural sanitizing agents, requires the definition of optimal conditions. The aim of the present work was to evaluate some antimicrobial activity parameters as mycelial growth inhibition, minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of six essential oils against Aspergillus niger, Aspergillus terreus,Chaetomium globosum, Penicillium chrysogenum, Penicillium pinophilum, Trichoderma harzianum and Trichoderma viride. The antimicrobial activity of essential oils was monitored by the macrodiluition technique. The mycelial growth inhibition, fungistatic and fungicidal concentrations were recorded for each strain that showed sensitivity to the essential oils. The essential oils of catnip, cinnamon, tea tree and thyme essential oils exhibited a large spectrum antimicrobial activities; those of clary sage and laurel inhibited the mycelial growth in a few fungal strains. The essential oils of cinnamon and thyme had the lowest MIC and MFC values against all the fungi assayed, followed by catnip, tea tree, clary sage and laurel. The use of these natural products rather than, the currently used antifungal chemicals, may be of interest given that: i) essential oils are of natural origin which means they are safer for human health and the environment and ii) there is less chance that the pathogenic microorganisms will develop resistance.

Identification and characterisation of human pathogenic filamentous fungi and susceptibility to Thymus schimperi essential oil

Twenty‐eight clinical fungal isolates were characterised by morphological (macro‐ and micro‐features and growth response at 25, 30 and 37 °C) and molecular (nuclear rDNA‐internal transcriber spacer, calmodulin, cytochrome c oxidase 1 and the largest subunit of RNA polymerase II) analyses. The clinical fungal isolates were ascribed to the following taxa: Penicillium chrysogenum, Verticillium sp., Aspergillus tubingensis, Aspergillus minutus, Beauveria bassiana and Microsporum gypseum. In addition, in vitro susceptibility testing of the isolates to conventional antifungal agents and to two chemically well‐defined chemotypes of Thymus schimperi essential oil was performed. Most of the isolates were resistant to amphotericin B (except A. minutus), and itraconazole, while terbinafine was quite active on these fungi. T. schimperi essential oil showed antifungal activity against all of the tested fungal isolates with minimal inhibitory concentration values similar or lower than those of terbinafine. Transmission electron microscopy analyses revealed that fungal growth inhibition by essential oil was accompanied by marked morphological and cytological changes.

Investigation of the cytotoxic, genotoxic, and apoptosis-inducing effects of estragole isolated from fennel (Foeniculum vulgare).

The present study was undertaken to evaluate, in the HepG2 human hepatoma cell line, the in vitro cytotoxic, genotoxic, and apoptotic activities of estragole (1), contained in the essential oil of Foeniculum vulgare (fennel) and suspected to induce hepatic tumors in susceptible strains of mice. Toward this end, an MTT cytotoxicity assay, a trypan blue dye exclusion test, a double-staining (acridine orange and DAPI) fluorescence viability assay, a single-cell microgel-electrophoresis (comet) assay, a mitochondrial membrane potential (Δψm) assay, and a DNA fragmentation analysis were conducted. In terms of potential genotoxic effects, the comet assay indicated that estragole (1) was not able to induce DNA damage nor apoptosis under the experimental conditions used.

Glaucopine C, a new diterpene from the fruiting bodies of Sarcodon glaucopus

In this work the mushroom Sarcodon glaucopus was studied. A new cyathane, glaucopine C (1), was isolated from the hexane extract and identified by 1H and 13C NMR spectra analysis. Glaucopine C showed anti-inflammatory acitvity.

Antibiofilm and Antioxidant Activity of Propolis and Bud Poplar Resins versus Pseudomonas aeruginosa

Pseudomonas aeruginosa is a common biofilm-forming bacterial pathogen implicated in lung, skin, and systemic infections. Biofilms are majorly associated with chronic lung infection, which is the most severe complication in cystic fibrosis patients characterized by drug-resistant biofilms in the bronchial mucus with zones, where reactive oxygen species concentration is increased mainly due to neutrophil activity. Aim of this work is to verify the anti-Pseudomonas property of propolis or bud poplar resins extracts. The antimicrobial activity of propolis and bud poplar resins extracts was determined by MIC and biofilm quantification. Moreover, we tested the antioxidant activity by DPPH and neutrophil oxidative burst assays. In the end, both propolis and bud poplar resins extracts were able to inhibit P. aeruginosa biofilm formation and to influence both swimming and swarming motility. Moreover, the extracts could inhibit proinflammatory cytokine production by human PBMC and showed both direct and indirect antioxidant activity. This work is the first to demonstrate that propolis and bud poplar resins extracts can influence biofilm formation of P. aeruginosa contrasting the inflammation and the oxidation state typical of chronic infection suggesting that propolis or bud poplar resins can be used along with antibiotic as adjuvant in the therapy against P. aeruginosa infections related to biofilm.

Diagnostic of the conservation state in the crypt of the Abbey of Montecorona: biological, microclimatic and geophysical evaluations

The Abbey S Salvatore of Montecorona, an important Benedictine monastary of the eleventh century, is placed at Umbertide, on the Northwest of Perugia (Italy). The site is in the Umbria region, characterized by a well-documented historical and instrumental seismicity, which periodically exposes this area to hazards with widespread damage for the population and the built-up environment. This paper focused on the study of the conservation state of the crypt of the Abbey. A multidisciplinary approach, using biological and physical non-destructive methods, is proposed. First, we investigated the microbial biodiversity of the crypt, analysing the presence of microorganisms by microscopic and cultivation methods. The second step was the study of the influence of the environment on the colonization and growth of these microorganisms, with a continuous monitoring of the microclimate inside the crypt, especially the thermo-hygrometric conditions. Moreover, with the aims of localizing the structures involved in the deterioration process, such as fractures, moisture, etc, ground penetrating radar (GPR) surveys, with different methodologies, were carried out in the crypt: reflection mode on the floor and traveltime tomography on the ceiling. From GPR data, a structure of archaeological interest was evidenced and, by means of a frequency signal analysis, the underground water content of the stone was also evaluated, assessing the correlation between the spectral content and moisture degree. The integration of information from these different methods provided some interesting results, also addressing possible interventions for protection and conservation of the crypt.

Chemical composition and fungicidal activity of the essential oil of Laserpitium garganicum from Italy

Laserpitium garganicum subsp. garganicum (Ten.) Bertol.(= Laserpitium siler L. subsp. garganicum (Ten.) Arcangeli) is a perennial herb belonging to the Apiaceae family. The distribution is limited to the southern area of the Balkan peninsula and Italy [1]. In Italy this plant is found in the central Apennines, Sicily and Sardinia [2]. This plant is described as a subspecies of L. siler or a species of Laserpitium in the Flora Europaea [1] and the Flora d’Italia [2] respectively. A few studies have reported the biologically active components isolated from L. siler, mainly sesquiterpene lactones [3–8], and one refers to sesquiterpene lactones from the roots of L. garganicum [9]. The essential oil composition of L. siler was also reported [10–13], but to the best of our knowledge, this is the first report on the GC/MS determination of the essential oil composition of the L. garganicum subsp. garganicum (Ten.) Bertol. Since the biological activity of this plant has not been studied, we focused our investigation on the antifungal activities of this essential oil against some phytopathogens and opportunistic human fungi. Fifty-six compounds were identified in L. garganicum essential oil, representing 92.3% of the total oil [14–19]. Table 1 shows the list of components identified and their percentages and retention indices. Compounds are listed in order of their elution from an HP-5. The most abundant compounds were myrcene (15.7%), β-phellandrene (14.4%), sabinene (9.7%), and γ-muurolene (7.8%). Monoterpene hydrocarbons made up 47.0% of the total oil; myrcene (15.7%) was the most abundant compound. Significant amounts of sesquiterpene hydrocarbons (25.0%) were found, with γ-muurolene (7.8%) being the main component. The oxygenated sesquiterpene fraction made up 9.8% of the total oil, with spathulenol (4.0%) having the highest content. The oxygenated monoterpenes (7.7%) also contributed with a similar content to the essential oil. This fraction was dominated by terpinen-4-ol (4.3%). Esters and ketones represented 1.8% and 0.6% of the total oil, respectively. The oil of L. garganicum differs markedly from the fruit oil of L. siler from southern France [13]; the later is characterizated by perillaldehyde (75.0%) and limonene (22.0%), compounds that were not found in L. garganicum oil. The oil from fruits of L. siler analyzed by Motl [10] contained perillaldehyde (89.5%) and limonene (10.5%). According to Adcock and Betts [11] the lack of perillaldehyde and limonene in L. garganicum is reason to consider these plants as a species of Laserpitium instead of a subspecies of L. siler despite the morphological similarities. Based on chemical composition, the plants analyzed in the present work were more similar to the other Laserpitium species reported by Adcock and Betts [11] (L. prutenicum L., L. hispidum Bieb., L. glaucum L., L. halleri Crantz, L. krapfii Crantz, L. archangelica Wulfen, L. latifolium L., and L. gallicum L.) than to L. siler. The antimycotic activity of essential oils depends on their chemical composition and may play a fundamental role in the host/pathogen relationship. Systemic fungal infections are important problems in medicine. Infections caused by fungal species are common in immunocompromised patients and result in significant treatment costs and mortality. Table 2 shows the antimicrobic activity of the essential oil of L. garganicum.

Composition of the Oil of Sideritis syriaca L. from Italy

Abstract The oils from leaves and inflorescences of Sideritis syriaca L. grown and harvested in Italy were analyzed by GC/MS. The major components in the oil from leaves contained hexadecanoic acid (31.1%), epi-α-bisabolol (14.5%), benzyl benzoate (7.5%), and (E)-caryophyllene (6.4%), while in the oil from the inflorescences contained epi-α-bisabolol (25.7%), benzyl benzoate (17.7%), hexadecanoic acid (7.8%), β-caryophyllene (7.3%), and (Z)-α-bisabolene (6.0%).

Human α-mannosidase produced in transgenic tobacco plants is processed in human α-mannosidosis cell lines

Deficiency in human lysosomal α-mannosidase (MAN2B1) results in α-mannosidosis, a lysosomal storage disorder; patients present a wide range of neurological, immunological, and skeletal symptoms caused by a multisystemic accumulation of mannose-containing oligosaccharides. Here, we describe the expression of recombinant MAN2B1 both transiently in Nicotiana benthamiana leaves and in the leaves and seeds of stably transformed N. tabacum plants. After purification from tobacco leaves, the recombinant enzyme was found to be N-glycosylated and localized in vacuolar compartments. In the fresh leaves of tobacco transformants, MAN2B1 was measured at 10,200 units/kg, and the purified enzyme from these leaves had a specific activity of 32-45 U/mg. Furthermore, tobacco-produced MAN2B1 was biochemically similar to the enzyme purified from human tissues, and it was internalized and processed by α-mannosidosis fibroblast cells. These results strongly indicate that plants can be considered a promising expression system for the production of recombinant MAN2B1 for use in enzyme replacement therapy.

Phytochemical Investigation on Leaf Extract of Cordia salicifolia Cham.

The dichloromethane extract of leaves of Cordia salicifolia Cham. (Family Boraginaceae) was fractionated by SiO(2) column chromatography and analyzed by gas chromatography, gas chromatography-mass spectrometry, and nuclear magnetic resonance spectroscopy. The apolar extract is characterized by a very high content of (+)-spathulenol (0.53%). The major component of the extract exhibited a very weak activity as an inhibitor of growth of Helicobacter pylori in vitro (minimum inhibitory concentration = 200 microg/mL).