In vitro antifungal and demelanizing activity of Nepeta rtanjensis essential oil against the human pathogen Bipolaris spicifera

The antifungal activity of Nepeta rtanjensis Diklić & Milojević essential oil was tested against the human pathogenic fungus Bipolaris spicifera (Bainier) Subramanian via mycelial growth assay and conidia germination assay. The minimally inhibitory concentration (MIC) of the oil was determined at 1.0 μg ml-1, while the MIC for the antifungal drug Bifonazole in a positive control was determined at 10.0 μg ml-1. The maximum of conidia germination inhibition was accomplished at 0.6 μg ml-1. In addition, at 0.6 μg ml-1 and 0.8 μg ml-1 the oil was able to cause morphophysiological changes in B. spicifera. The most significant result is the bleaching effect of the melanized conidial apparatus of the test fungi, since the melanin is the virulence factor in human pathogenic fungi. These results showed the strong antifungal properties of N. rtanjensis essential oil, supporting its possible rational use as an alternative source of new antifungal compounds

Biofilm forming cyanobacteria, algae and fungi on two historic monuments in Belgrade, Serbia

Biofilm on the sandstone substrata of the bridge 'Brankov most' and on the granite substrata of the 'Monument of the Unknown Hero' contains a complex consortia of cyanobacteria, algae, and fungi. Coccoid and filamentous cyanobacteria, green algae and diatoms make up the photosynthetic part of the biofilm while hyphal fragments, chlamydospores, fruiting bodies and spores take part as fungal components. These structures make a dense layer by intertwining and overlapping the stone surface. Five cyanobacterial, 11 algal and 23 fungal taxa were found. The interaction of the biofilm's constituents results in the bioweathering of the stone substrata through mechanical penetration, acid corrosion and the production of secondary mycogenic biominerals.

Preserving the Danube Limes in Serbia: A Review on the Biodeterioration of Trajan’s Bridge

One of the most significant monuments of the Roman Danube Limes is Trajan's Bridge, built in the period from 103 to 105 AD. The remains of the pillars on the Serbian bank of the Danube were partially restored four decades ago. Today, the pillar that is closest to the river, which has not undergone conservation, is subject to different types of deterioration. During the comparison between the present condition of the pillar and those recorded in photos over the last six decades, we can estimate that its level of material loss has not overly changed. However, the difference in biological growth is visible. The primary aim of this study was to record the degree of the infestation and endangerment of the monument and check for possible risks for future mortar deterioration where mortar is in direct contact with severely infested bricks. Moreover, a characterisation of the biodeteriogens was performed. Special emphasis was given to fungi as the main agents of deterioration. A precise assessment of the level of risk they pose to this monument was made as a basis for the formulation and implementation of appropriate conservation treatments. Severe macrofouling by epilithic lichenised fungi and mosses was documented. Even in areas where pillars lack visible infestation, thriving microbial communities characterized by the presence of various fungal structures, as well as structures of trichal Cyanobacteria, and Chlorophyta were recorded. Similarities between communities documented on brick, mortar, and stone surfaces estimated via Sørensen’s quotient of similarity, were high, with the highest similarity documented between mortar and stone

Comparison of anti-Aspergillus activity of Origanum vulgare L. essential oil and commercial biocide based on silver ions and hydrogen peroxide

The antifungal activities of Origanum vulgare essential oil (EO) and of a biocide based on silver and hydrogen peroxide (Sanosil S003) against seven Aspergillus species isolated from different substrata (stone, brick, silk and paper) of cultural heritage objects in Serbia were evaluated. Microdilution, agar dilution and microatmosphere methods were used to determine minimal fungistatic and minimal fungicidal concentrations (MIC and MFC), and light microscopy to determine structural abnormalities. MIC and MFC values for O. vulgare EO ranged from 0.2 to 5 mg mL−1 and for Sanosil S003 from 5 to 250 mg mL−1. Aspergillus sp. sect. fumigati was the most susceptible isolate, where MIC and MFC values were achieved at 0.5 mg mL−1 for O. vulgare EO, while MIC and MFC values for Sanosil S003 were achieved at 5 and 10 mg mL−1, respectively. Morpho-physiological changes were documented in all isolates, including lack of sporulation, depigmentation of conidiogenous apparatus and conidia, and presence of aberrant fungal structures. O. vulgare EO exhibited stronger anti-Aspergillus activity than Sanosil S003, as demonstrated by the higher MIC and MFC values and fewer morpho-physiological changes observed in the tested Sanosil S003 concentrations. O. vulgare EO could be an excellent alternative to commercial biocides, with high potential in the field of cultural heritage conservation

Editorial: Chemical ecology of arthropods, plants, and fungi: bioactivity and importance of natural products

Bioactivity and Importance of Natural Products" was intended to be a collection of The authors declare that the research was conducted in the absence of any commercial 100 or financial relationships that could be construed as a potential conflict of interest.Publisher's note 103 104 All claims expressed in this article are solely those of the authors and do not 105 necessarily represent those of their affiliated organizations, or those of the publisher, the 106 editors and the reviewers. Any product that may be evaluated in this article, or claim that may 107 be made by its manufacturer, is not guaranteed or endorsed by the publisher

Mold attack on frescoes and stone walls of Gradac monastery

Microfungi can colonize stone surfaces and form sub-aerial biofilms which can lead to biodeterioration of historic monuments. In this investigation samples for mycological analyses were collected from stone material with visible alteration on stone walls of Gradac monastery exterior. The prevailing fungi found on stone walls were dematiaceous hyphomycetes with melanized hyphae and reproductive structures (Alternaria, Aureobasidium, Cladosporium and Epicoccum species). The frescoes inside the monastery building were also analyzed for the presence of mycobiota. The predominant fungi found on frescoes were osmophilic species from genera Aspergillus and Penicillium. The significant result is identification of human pathogen species Aspergillus fumigatus on frescoes

The effect of Nepeta rtanjensis essential oil on test micromycetes mycelia growth

The antifungal activity of Nepeta rtanjensis Diklić et Milojević essential oil on mycelia growth has been performed by macrodilution method. The most efficient impact of N. rtanjensis essential oil on mycelia growth in vitro was found in Alternaria species with the same value of minimal inhibitory quantity (MIQ) of 0.6 μl/ml. Bipolaris spicifera and Cladosporium cladosporoioides had MIQ values of 1.0 μl/ml whereas Trichoderma viride with MIQ value of 1.6 μl/ml showed the most efficient defense against the essential oil examined. The values of minimal fungicidal quantity (MFQ) in Alternaria sp. 2, B. spicifera and C. cladosporioides match the MIQ values whereas MFQ values in Alternaria sp. 1 is 0.8 μl/ml, and in T. viride 1.8 μl/ml.Makrodilucionom metodom testiran je uticaj etarskog ulja endemične biljke Nepeta rtanjensis (Lamiaceae) na micelijalni rast mikromiceta: Alternaria sp. 1, Alternaria sp. 2, Bipolaris spicifera, Cladosporium cladosporioides i Trichoderma viride. Hemijska analiza etarskog ulja N. rtanjensis pokazala je apsolutnu dominaciju 4aα, 7α, 7aβ nepetalaktona (79.89%). Najefikasniji uticaj na rast micelije in vitro zabeležen je kod vrsta roda Alternaria sa istom vrednošću minimalne inhibitorne količine (MIK) od 0.6 μl/ml. Bipolaris spicifera i Cladosporium cladosporioides su imali MIK 1.0 μl/ml, dok je Trichoderma viride, sa vrednošću MIK od 1.6 μl/ml, pokazala najveću otpornost na dejstvo ispitivanog ulja. Vrednosti minimalne fungicidne količine (MFK) se kod Alternaria sp. 2 (0.6 μl/ml), B. spicifera (1.0 μl/ml) i C. cladosporioides (1.0 μl/ml) poklapaju sa vrednostima MIK, dok je kod Alternaria sp. 1 MFK 0.8 μl/ml, a kod T. viride 1.8 μl/ml. Etarsko ulje N. rtanjensis pokazalo je jako antifungalno dejstvo na rast micelije testiranih mikromiceta.nul

Morphology, distribution, and histochemistry of trichomes of Thymus lykae Degen & Jav. (Lamiaceae)

Micromorphology, distribution, and histochemistry of the trichomes of Thymus lykae were studied using scanning electron microscopy (SEM)and confocal laser scanning electron microscopy (CLSM). The leaves, stem, and calyx bear numerous glandular and non-glandular trichomes. Two types of glandular trichomes are identified - peltate and capitate. Results of histochemical tests showed positive reactions to polysaccharides, proteins, and lipids. Yellow autofluorescence of secreted material was noticed in peltate and capitate trichomes. Strong reddish-yellow autofluorescence of the lipophilic and hydrophilic secreted material was observed with CLSM.Mikromorfologija, distribucija i histohemijska analiza trihoma kod vrste Thymus lykae urađena je korišćenjem skening elektronskog mikroskopa i konfokalnog laserskog skening mikroskopa. Nežlezdane, negranate i dva tipa žlezdanih trihoma - peltatne i kapitatne opisane suuovom radu. Brojne nežlezdane i žlezdane trihome nalazile suse kako na listovima (i na licu i na naličju)tako i na stablu i na čašici. Rezultati histohemijskih istraživanja pokazala supozitivne reakcije na polisaharide, lipide i proteine. Sekretorni produkti unutar peltatnih trihoma imali sujako žutu autofluorescenciju, dok je u kapitatnim trihomama zapažena slabija autofluorescencija. Korišćenjem CLSM uočena je jarko crveno-žuta autofluorescencija lipofilnih i hidrofilnih sekretornih materija u žlezdanim trihomama.Projekat ministarstva br. 14304

Antifungal activity of Nepeta rtanjensis essential oil

The chemical composition and antifungal activity of the essential oil of an endemic Serbian plant Nepeta rtanjensis Diklić & Milojević was studied. The essential oil was isolated from cultivated plants. Inhibition of mycelia growth of five micromycetes, two Alternaria species originally isolated from N. rtanjensis, Cladosporium cladosporoides, Trichoderma viride and Bipolaris spicifera, were tested using the agar dilution method. The essential oil of N. rtanjensis, the main component of which was 4aα,7α,7αβ-nepetalactone, showed strong antifungal activity against all the tested micromycetes. The minimum inhibitory concentration of N. rtanjensis essential oil ranged from 0.6 to 1.4 μg mL-1. The fungi most sensitive to the tested oil were Alternaria species, while Trichoderma viride was the most resistant.U ovom radu prezentovan je hemijski sastav i antifungalna aktivnost etarskog ulja endemične biljke Nepeta rtanjensis Diklić & Milojević. Etarsko ulje je izolovano iz kultivisanih biljaka. Inhibicija micelijalnog rasta pet mikromiceta, dve vrste roda Alternaria, izolovane sa N. rtanjensis, Cladosporium cladosporioides, Trichoderma viride i Bipolaris spicifera, testirana je makrodilucionom metodom. Etarsko ulje N. rtanjensis, čija je glavna komponenta 4aα,7α,7aβ-nepetalakton pokazuje jaku antifungalnu aktivnost u odnosu na sve testirane mikromicete. Minimalna inhibitorna koncentracija (MIC) etaskog ulja bila je u rasponu od 0,6 μg mL-1 do 1,4 μg mL-1. Najveću osetljivost na testirano ulje pokazale su vrste roda Alternaria dok je Trichoderma viride bila najotpornija.Projekat ministarstva br. 143041

Toxigenic and pathogenic fungi in Norway rat (Rattus norvegicus Berk., 1769) from natural populations in semiagricultural habitats

In this study, the presence of toxigenic and pathogenic fungi was detected in individuals of natural populations of Norway rats from semiagricultural habitats. The presence of fungi was noted in 19 out of 30 (63%) individuals examined. Six fungal species were isolated and identified, of which majority belonged to Hyphomycetes (Deuteromycotina) and Mucor racemosus from Zygomycotina. All of detected species are of public health importance and some of them might influence animals health.U ovom radu su prikazana istraživanja prisustva toksigenih i patogenih gljiva u jedinkama sivog pacova (Rattus norvegicus Berk., 1769) iz prirodnih populacija sa polupoljoprivrednih staništa (Omoljica, Kovin, Leštane, Ovča). Detekcija prisustva gljiva u biološkom materijalu (bris kože nosne šupljine i homogenat pluća) je vršena na selektivnoj Sabouraud Maltose Agar (SMA) podlozi. Istraživanje je pokazalo prisustvo šest vrsta gljiva od kojih pet pripada klasi Hyphomyceta (Deuteromycotina), a Mucor racemosus klasi Zygomycotina. Vrste roda Aspergillus su detektovane u homogenatima pluća šest jedinki, a Penicillium kod pet jedinki. Paecilomyces varioti je izolovan iz tkiva šest jedinki sivog pacova. Brisevi kože nosne šupljine su dali pozitivne rezultate u 15 (50%) od 30 jedinki (četiri pozitivna za Aspergillus, četiri za Penicillium, šest za Paecilomyces varioti i jedna za Mucor racemosus). Međutim, u samo 9 slučajeva zabeleženo je poklapanje prisustva gljiva u koži nosne šupljine i pluća. Nalazi koji pokazuju prisustvo patogena, izazivača teških gljivičnih oboljenja, ukazuju na sivog pacova kao na potencijalni rezervoar ovih agenasa. Dobijeni podaci predstavljaju, prema našem saznanju, prve podatke o prisustvu gljiva kod pacova iz prirodne sredine zabeležene kod nas.Projekat ministarstva br. 14303