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Plastic waste has become a serious global challenge that calls for sustainable solutions and requires rapid actions. Biocatalysis could present an adequate answer to this problem by providing different enzymes capable of degrading plastic polymers. Streptomyces strains as predominant soil inhabitants have also adapted to the presence of variety of plastic waste in natural environments, so they have been examined for the plastic degrading capabilities. The aim of this work was to improve the biocatalytic properties of Streptomyces strains for their use in biodegradation of plastic polymers and develop a system for heterologous expression of polyethylene therephtalate (PET) degrading enzymes in Streptomyces spp. Well studied Streptomyces lividans TK24 and S. albus NRRL B-1335, as well as two newly isolated Streptomycetes were used for expression of benchmark PETases and cutinases. Enzymes were cloned into pGM1202 Escherichia coli–Streptomyces shuttle vector and subsequently introduced into Streptomyces hosts either by polyethylene glycol-mediated protoplasts transformation or by electroporation. Cell-free extracts and supernatants of transformed cells were tested on different plastics using bis(2-hydroxyethyl) terephthalate (BHET), polycaprolactone (PCL) and Impranil as substrates in plate assays. Expression of leaf-branch compost cutinase in S. albus and S. lividans resulted in an 8.5- and 2.5- times increase in esterase activities, respectively. Introduction of the enzyme into newly isolated strains that already showed some plastic degrading activity resulted in synergistic activity of the recombinant strains.

The book Perspectives on Mentorship – Reinventing Mentoring in Arts and Creative Industries Management offers a holistic view with multiple perspectives to the topic of mentorship in arts and cultural context. It can be used as a course book for mentorship programmes, providing further knowledge for anyone working in mentorship or planning to build a mentorship programme in the context of arts management education within art or cultural institutions. It provides a unique exploration of this subject by presenting different perspectives, raising thought provoking questions, and examining ways to manage a mentoring programme. It is important to remember that mentoring does not happen by itself, and that it requires management and intervention in order to be sustainable. University students interested in arts management will find the book invaluable in obtaining a better understanding of how mentoring could be approached and help them in the development of their professional identity. It does not present one universal truth or method, but instead is about sharing experiences. From the academic perspective, the book encourages readers to approach mentoring with an open mind, offering tools to reflect on the process of building programmes around the core of mentoring – a dynamic human relationship which affects the identity of both parties – and then to build on the different layers around that foundation. The book seeks to provide insights into the different layers that are created during the mentoring process. It poses a variety of questions that can apply to specific programmes and helps readers understand how to effectively manage and sustain mentorship relationships.

A wide occurrence of wilt and rot caused by Fusarium species has been observed in the last few years in many vegetable-growing areas in the Republic of Serbia. Symptoms of rot and wilt of celery, garlic, and onion were noticed and after determination, Fusarium spp. was identified as the main causal agent of the disease. Most of the Fusarium species that cause disease on vegetable crops (garlic, onion, celery) overwinter in soil debris and soil. This study was conducted to isolate and identify Fusarium from soil samples by conventional and molecular methods. Soil samples were taken under the diseased plant, and 25 samples were collected in order to perform isolation of Fusarium species that cause rot and wilt during production.

The results of long-term groundwater monitoring in the Bileća reservoir adjacent (eastern Herzegovina, Bosnia and Herzegovina) indicate that there is a good hydraulic connection between the reservoir and the karst aquifer located in the right bank of the reservoir. In remote parts of the right-bank karst aquifer, due to complex lithostratigraphic characteristics and a tectonic structure, the influence of the reservoir is very variable and has been insufficiently studied up until now. This paper presents the analysis and synthesis of new, relevant hydrogeological data, as a basis for the creation of a 3D spatial model, i.e., the analysis of the karst system’s behaviour, both under regular and artificial hydrological conditions of surface reservoir construction and its continuous use (filling and emptying). The interactive connection of the model and complex surface and groundwater time series monitoring data of this system is presented through the analysis of its hydrodynamic characteristics, which completes the spatial model of the karst regime caused by low and high groundwater levels and low and high reservoir water levels. The integration of all the data into one model and further multiparametric analyses revealed the different types of hydrodynamic conditions prevailing in the karst aquifer with regard to the influence of the high or low waters of the reservoir.

Objectives: The study aimed to determine the relationship between the mandibular asymmetry index according to Kjellberg between patients with painful unilateral anterior disc displacement (DD) and asymptomatic volunteers without disc displacement. Vertical measurements were performed on a panoramic single-image radiograph, and the disc status was confirmed by magnetic resonance imaging (MRI). Material and methods: Two groups of subjects were retrospectively selected, 40 patients (the overall mean age was 35.5 years; 75% female) with temporomandibular disorder symptoms confirmed by RDC/TMD axis I and manual functional analysis. Unilateral DD was determined by MRI. A comparative group of asymptomatic volunteers (20 dental students with a mean age of 23.4 years; 72% female) had the physiological position of the disc determined by MRI. The vertical asymmetry of the condyle was determined by the method of Kjellberg et al. The symmetry of the gonial angle of the mandible was also measured. Results: A comparison of the mean of the asymmetry index between patients (average 90.89±7.08%) and asymptomatic volunteers (mean 95.86±4.44%) showed a statistically significant difference (p=0.0029). There was no difference (p=0.088) in gonial angle symmetry between the patients (mean 96.48±2.96°) and the asymptomatic volunteers (mean 97.52±2.31°). The distribution of the presence of individual DD diagnoses (partial and total displacement with reduction, displacement without reduction) in patients diagnosed with asymmetry of the mandible was without statistical significance (p>0.05). Conclusion: This study actually points to the asymmetry of the mandible as a potential morphological risk of anterior DD., Svrha istraživanja: Cilj istraživanja bio je utvrditi povezanost indeksa asimetrije mandibule prema Kjellbergu između pacijenata s bolnim unilateralnim anteriornim pomakom diska i asimptomatskih dobrovoljaca bez pomaka diska. Vertikalna mjerenja obavljena su na ortopatomogramima, a status diska potvrđen je magnetskom rezonancijom. Materijal i metode: Retrospektivno su odabrane dvije skupine ispitanika od 40 pacijenata (prosječna dob 35,5 godina; 75 % ženskoga spola) sa simptomima temporomandibularnog poremećaja potvrđenima RDC/TMD-om os I i manualnom funkcijskom analizom. Unilateralni pomak diska ustanovljen je magnetskom rezonancijom. Usporednoj skupini asimptomatskih dobrovoljaca (20 studenata stomatologije prosječne dobi 23,4 godine; 72 % ženskoga spola) utvrđen je fiziološki položaj diska magnetskom rezonancijom. Vertikalna asimetrija kondila određena je metodom prema Kjellbergu i suradnicima. Mjerena je i simetrija gonijalnog kuta mandibule. Rezultati: Usporedba prosjeka indeksa asimetrije između pacijenata (prosjek 90,89 ± 7,08 %) i asimptomatskih dobrovoljaca (prosjek 95,86 ± 4,44 %) pokazala je statistički značajnu razliku (p = 0,0029). Nije bilo razlike (p = 0,088) u simetriji gonijalnog kuta između pacijenata (prosječno 96,48 ± 2,96°) i asimptomatskih dobrovoljaca (prosječno 97,52 ± 2,31°). Bez statističke značajnosti (p > 0,05) bila je distribucija prisutnosti pojedinih dijagnoza pomaka diska (djelomični i potpuni pomak s redukcijom, pomak bez redukcije) kod pacijenata kojima je utvrđena asimetrije mandibule. Zaključak: Ova studija dopušta povezivati asimetriju manidbule kao potencijalni morfološki rizik za nastanak anteriornoga pomaka diska.

The ambigols are cyanobacterial natural products characterized by three polychlorinated aromatic building blocks connected by biaryl and biaryl ether bridges. All ambigols known to date possess promising biological activities. Most significantly, ambigol A was reported to have antibacterial activity against Gram-positive bacteria, such as Bacillus megaterium and B. subtilis. We established a diverse compound library for in-depth biological evaluation building on our previous bio- and total synthetic research on this natural product family. To explore the antimicrobial potential in detail and to determine initial structure–activity relationships of this product class, a large set of dimeric and trimeric compounds were screened against selected bacterial and Candida target strains. Our results reveal exceptional antibiotic activity of the ambigols, especially against challenging clinical isolates.

Antibacterial hydrogels, as an advanced approach, can create optimal conditions for wound healing, even in the fight against stubborn and difficult-to-treat wound infections. Interestingly, pH is an often neglected clinical parameter, although it has a significant impact on the wound healing process. At different stages of wound healing, the pH in the wound bed changes from slightly alkaline to neutral to acidic. To develop novel pH-sensitive antibacterial hydrogel dressings, Zn2+-loaded poly(2-hydroxyethyl acrylate/itaconic acid) hydrogels were synthesized. The hydrogels exhibit pH-sensitive swelling in the physiologically relevant pH range, with a pronounced swelling ability at neutral pH. The controlled release of Zn2+ occurs in a buffer of pH 7.40 at 37°C. The liquid transport mechanism and release kinetics are evaluated using the specific kinetic models of Ritger-Peppas and Peppas-Sahlin. The effect of Zn2+ on structural, thermal, swelling, cytocompatibility, and antibacterial properties is evaluated by Fourier transform infrared spectroscopy, differential scanning calorimetry, swelling studies, MTT, and antibacterial tests. The hydrogels show excellent antibacterial activity against Escherichia coli. The research opens new perspectives for efficient wound healing management, and the extension of the study will be orchestrated by optimising the hydrogel composition to achieve improved performance. This article is protected by copyright. All rights reserved

In the present study, synthesis of silver(I) and gold(III) coordination compounds with 1,6-naphthyridine (1,6-naph), {[Ag(1,6-naph)(H2O)](BF4)}n (1) and [AuCl3(1,6-naph)] (2), was reported. The methods used for the structural characterization of a new compound 1 included IR, NMR (1H and 13C) and UV-Vis spectroscopy, cyclic voltammetry and single-crystal X-ray diffraction analysis. The crystallographic results showed that compound 1 represents silver(I) coordination polymer, in which 1,6-naph ligand acts as a bidentate bridging ligand connecting two Ag(I) ions via its N1 and N6 nitrogen atoms, while the third coordination site of the metal ion is occupied by the water oxygen atom, resulted in a T-shape geometry. Compounds 1 and 2 were evaluated in vitro for antimicrobial activity against five bacterial and two Candida species, while their cytotoxicity was tested on the normal human lung fibroblast cell line (MRC-5). Compound 1 has manifested a remarkable antifungal activity on both tested Candida strains (C. albicans and C. parapsilosis) with minimal inhibitory concentrations (MICs) of 1.43 and 11.38 µM (0.49 and 3.9 µg/mL), respectively, while no significant antimicrobial activity was observed for 2. Moreover, silver(I) coordination polymer 1 inhibits the hyphae formation of C. albicans at subinhibitory concentration. The binding affinity of both compounds 1 and 2 with calf thymus DNA (ct-DNA) and bovine serum albumin (BSA) was studied by fluorescence spectroscopy, indicating their ability to interact with these biomolecules, with compound 2 being more reactive.

The myxobacterial natural product myxocoumarin A from Stigmatella aurantiaca MYX-030 has remarkable antifungal activity against agriculturally relevant pathogens. To broaden the initial evaluation of its biological potential, we herein completed the first total synthesis of myxocoumarin A. This synthetic access facilitated stereochemical investigations on the natural product structure, revealing its (R)-configuration. Biological activity profiling showed a lack of activity against Candida spp. and Gram-negative bacteria but revealed strong antibiotic activities against Bacillus subtilis and Staphylococcus aureus, including MRSA.

The genus Streptomyces has been studied for the vast secondary metabolite production, biological activity of crude extracts, as well as colouring properties on textile materials [1, 2]. Streptomyces sp. BV365 is a potent producer of yellow pigments, used to efficiently colour different natural textiles [3]. Utilization of food waste for bacterial growth and production of pigments and antifungals [4] could contribute to conversion of waste to valuable molecules, providing more economically acceptable and more eco-friendly generated biotherapeutics, enzymes and pigments.

Cisplatin is one of the most used anticancer agents, and along with carboplatin and oxaliplatin, is a part of more than 50% of clinically applied anticancer regimens [1]. However, the side effects of cisplatin are severe and include dose-limiting toxicity, such as neurotoxicity, nephrotoxicity and ototoxicity. Platinum(II) complexes with different structure from cisplatin provide many opportunities for design of novel antitumor drugs with improved pharmacological properties. Considering this, in the present study, new platinum(II) complexes with phenothiazine (phtz) and N-methylphenothiazine (N-Mephtz), [PtCl2(phtz)(CH3CN)] (1) and [PtCl2(N-Mephtz)(CH3CN)] (2), were synthesized. These complexes were characterized by elemental microanalysis, NMR (1H and 13C) and IR spectroscopic measurements, while the structure of complex 1 was determined by single-crystal X-ray diffraction analysis. The antitumor activity of the platinum(II) complexes was tested in vitro against a panel of human cancer cell lines, including A549 (lung cancer), A375 (melanoma, skin cancer), MDA-MB-231 (breast cancer), and HCT116 (colon cancer). To check the selectivity of the synthesized complexes 1 and 2, a healthy MRC-5 cell line (lung fibroblasts) was also included in this study.

Potato industry is one of the major food industries that generates considerable amounts of potato peels and wastewater (1). These wastes can then be utilized as components of microbial media in biotechnological production of pyocyanin (PYO) and 1-hydroxyphenazine (1-HP) using Pseudomonas aeruginosa (2). PYO and 1-HP possess important biological activities, thus could be applied in the field of medicine, and can be used as biocontrolling agents (2). However, their application is hindered due to high costs associated with their large scale production. In this work, we established a fermentation process which utilizes either potato peels or potato wastewater as the sole nutrient source to obtain PYO and 1-HP. P. aeruginosa BK25H strain was selected from our in-house collection. This approach afforded 10 mg/l PYO and 9 mg/l 1-HP using potato wastewater and 15 mg/l PYO and 11 g/l 1-HP using potato peels after 24 h incubation. This work is the step towards zero-pollution and conversion of waste to valuable microbial products.

U radu se analiziraju prostorni raspored i mogućnosti antifašističke materijalne baštine za razvoj memorijalnog turizma u općinama i gradovima Južne Istre. U prvoj polovici 20. stoljeća antifašistička borba u Istri bila je ključni dio nekoliko političkih prekretnica. Te povijesne prekretnice imale su dalekosežne posljedice i najvećim dijelom bile su obilježene oružanim sukobima, pojedinačnim i masovnim ljudskim žrtvama i terorom nad stanovništvom. Motiv putovanja u memorijalnom turizmu ovdje je obilazak mjesta gdje su se ovi tragični događaji dogodili i komemoracija žrtvama. Cilj istraživanja bio je utvrditi geografski raspored antifašističke materijalne baštine u Južnoj Istri i njezinu pogodnost za razvoj memorijalnog turizma. Dodatni cilj bio je predložiti tematske rute memorijalnog turizma u općinama i gradovima Južne Istre. Korištene su metode analize povijesnih istraživanja, terenskog rada, sudioničkog promatranja, prostorne i GIS analize. Istraživanje je pokazalo da šest južno istarskih općina i dva grada imaju 167 dobro očuvanih i obilježenih materijalnih spomenika antifašizma. Najveći broj spomenika nalazi se u središnjem dijelu grada Pule. Glavni doprinos ovog članka bio je prevrednovanje materijalne baštine antifašizma kao potencijalnog resursa za razvoj memorijalnog turizma kao inovacije u turističkoj ponudi Istre., This paper analyses the spatial layout and possibilities of the antifascism tangible heritage for memorial tourism development in the municipalities and towns of Southern Istria. In the first half of the 20th century, the antifascist struggle in Istria was a crucial part of several political turning points. Those historical turning points had far-reaching consequences and, for the most part, were marked by armed conflicts, individual and mass human casualties and terror over the population. The motive of travel in memorial tourism here is to visit the places where these tragic events occurred and commemorate the victims. The aim of the research was to determine the geographical distribution of the antifascism tangible heritage in Southern Istria and their suitability for the development of memorial tourism. An additional objective was to propose thematic routes of memorial tourism in Southern Istrian municipalities and towns. Methods of analyses of historical research, fieldwork, participant observation, spatial and GIS analysis were used. The survey indicated that six South Istrian municipalities and two towns have 167 well-preserved and marked tangible antifascism monuments. The largest number of monuments are located in the central district of the city of Pula. The main contribution of this article was to provide re-evaluation of antifascism tangible heritage as the potential resource for the memorial tourism development as the innovation in the tourism supply of Istria.

This is the first report on the separation and biological assessment of all metabolites derived from Pulicaria armena (Asteraceae) which is an endemic species narrowly distributed in the eastern part of Turkey. The phytochemical analysis of P. armena resulted in the identification of one simple phenolic glucoside together with eight flavon and flavonol derivatives whose chemical structures were elucidated by NMR experiments and by the comparison of the spectral data with the relevant literature. The screening of all molecules for their antimicrobial, anti-quorum sensing, and cytotoxic activities revealed the biological potential of some of the isolated compounds. Additionally, quorum sensing inhibitory activity of quercetagetin 5,7,3’ trimethyl ether was supported by molecular docking studies in the active site of LasR which is the primary regulator of this cell-to-cell communication system in bacteria. Lastly, the critical molecular properties indicating drug-likeness of the compounds isolated from P. armena were predicted. As microbial infections can be a serious problem for cancer patients with compromised immune systems, this comprehensive phytochemical research on P. armena with its anti-quorum sensing and cytotoxic compounds can provide a new approach to the treatment.