Broth depending production of extracellular enzymes by enterobacteria isolated from dairy food (Serbian cheese)

In this paper, we investigated, for the first time, the enzyme activity of enterobacteria from cheese from Southeastern Serbia (Sokobanja), which was produced in a traditional way. The tested bacteria were selected from the spring, summer, and autumn collections and grown in two different broths. The enzyme activity was investigated in the two broths and measured using spectrophotometry method. It was concluded that there were differences in the amount of extracellular enzymes depending on the broths. A statistically significant rise in the amount of enzymes was demonstrated in Tripton soy broth. Bacteria in cheese do not possess the ability to produce extracellular enzymes in large amounts. Therefore, they do not change the organoleptic characteristics of the cheese. There is a possibility that if they are found outside their natural environment (cheese), without interactions with antagonists, they may exhibit stronger enzyme activity.Publishe

Detection of enzymes produced by lactic acid bacteria isolated from traditionally made Serbian cheese and their role in the formation of its specific flavor

Nine species (sixteen isolates) of lactic acid bacteria (LAB) isolated from traditionally made Serbian cheese were evaluated for their enzymatic activities in order to select indigenous strains of technical interest for the manufacture of cheese. These strains were selected based on their previously determined biochemical and physiological characteristics, as well as their antimicrobial activity, and were identified as Lactococcus lactis subsp. lactis (one isolate), Lc. lactis subsp. lactis biovar. diacetylactis (five isolates), Lactobacillus fermentum (two isolates), Lb. plantarum (one isolate), Lb. brevis (one isolate), Enterococcus faecalis (three isolates), E. faecium (one isolate), E. durans (one isolate) and E. hirae (one isolate). The enzymatic activities (acid and alkaline invertases, alkaline phosphatase, alkaline protease, a-amylase) were measured by using the spectrophotometric method. The results indicated that all Lactobacillus isolates showed protease, amylase, and alkaline phosphatase activities, while the activities of acid and alkaline invertases were not observed. The Lactococcus isolates showed protease, acid invertase and alkaline phosphatase activities, except the KGPMF50 isolate, which showed no alkaline phosphatase activity. The tested Enterococcus isolates showed weakly and strain-specific enzymatic activity. The results indicated that the enzymes produced by the investigated strains have a role in the formation of the specific flavor of cheese and that these isolates, especially Lactobacillus isolates, showed the potential for use in the dairy industry or applied biotechnology.Publishe

The application of benthic diatoms in water quality assessment (Mlava River, Serbia)

The main objective of this study was to assess the ecological status of the Mlava River based on epilithic diatoms and to test the use of diatom indices as a tool for estimating the quality of flowing waters in Serbia. Quantitative analysis showed that in April Achnanthidium minutissimum was dominant at each site, except at the fi fth site, where Amphora pediculus was dominant. In July and September, Achnanthidium minutissimum, Achnanthidium pyrenaicum, Amphora pediculus, Denticula tenuis, Diatoma vulgaris, Gomphonema elegantissimum, Cocconeis pseudolineata and Cocconeis placentula var. lineata dominated. Detrended correspondence analysis (DCA) was used to detect the major patterns of variation in species composition. The first DCA axis summarizes the distribution of the diatom community, mainly through temperature, conductivity, oxygen and water hardness gradient. The second DCA axis was weakly correlated with few variables. Based on the average values of the pollution sensitivity index (IPS), commission for economical community metric (CEE) and biological diatom index (IBD), the water of the Mlava River belonged to water class I during all three seasons. Values of the diatom-based eutrophication/pollution index (EPI-D) indicated class II water quality. According to calculated trophic diatom index (TDI) values, water of the Mlava River was characterized by intermediate nutrient concentrations during three seasons. Principal components analysis was used to represent the correlation between diatom indices, and the highest correlation among the selected diatom indices is seen between EPI-D, IPS and IBD

Sinteza I karakterizacija kompleksa cinka(II), paladijuma(II) I platine(II) sa 2’-[1-(2-piridinil)etiliden]oksamohidrazidom - kristalna struktura bis {2’-[1-(2-piridinil)etiliden]oksamohidrazido}cink(II) trihidrata

Complexes of Zn(II), Pd(II) and Pt(II) with 2'-[1-(2- pyridinyl)ethyhdene]oxamohydrazide (Hapsox) were synthesized and their structures were determined. All the complexes are of a neutral type with two apsox ligands coordinated to Zn(II) and one apsox ligand coordinated to Pd(II) or Pt(II). In each case. the polydentate was coordinated via pyridine and hydrazone nitrogens and alpha-oxyazine oxygen. forming an octahedral geometry around Zn(II). and a square planar one around Pd(II) and Pt(II). The structure determination was performed by IR. H-1-NMR and C-13-NMR spectroscopy, and for the Zn(II) complex by X-ray structure analysis.U ovom radu opisana je sinteza i strukturna karakterizacija kompleksa Zn(II) Pd(II) i Pt(II) sa 2’-[1-(2-piridinil)etiliden]oksamohidrazidom (Hapsox). Sva tri dobijena kompleksa su neutralnog tipa sa dva koordinovana apsox liganda u slučaju kompleksa Zn(II), odnosno jednim apsox ligandom u slučaju Pd(II) i Pt(II) kompleksa. Koordinacija polidentata je u svim kompleksima ostvarena preko piridinskog azota, hidrazonskog azota i α-oksiazinskog kiseonika gradeći oktaedarsku geometriju oko Zn(II), odnosno kvadratno planarnu geometriju oko Pd(II) i Pt(II).Potvrdu za ovakve strukture dobili smo iz IC 1H-NMR i 13C-NMR spektara, dok je za Zn(II) kompleks urađena i rendgenska strukturna analiza

Herpesviruses in Periapical Pathoses: An Updated Systematic Review

Apical periodontitis represents a chronic inflammation and destruction of periradicular tissue caused by polymicrobial infection of endodontic origin. The aim of this systematic review was to make an update on findings related to Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) presence in periapical pathoses and to correlate these findings with clinical, histopathological and radiographic features of periapical lesions. Methods were based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. A search was performed using PubMed, Web of Science and SCOPUS. Search key words included the following medical subjects heading terms: (periapical disease OR apical periodontitis OR periapical lesions OR periapical abscess) AND (viruses OR herpesvir*). A manual search involved references from articles retrieved for possible inclusion. The search, evaluation, and critical appraisal of articles were performed by two independent judges. Collected data were analyzed using the measures of descriptive statistics. The final review has included twenty nine articles related to herpesviral presence periapical pathoses. Qualitative analysis indicated that EBV HCMV, and HHV-8 were the most prevalent species in periapical pathoses. Our findings suggest that there is wide variety of herpesviruses detection rates in periapical pathoses in relation to their clinical, histopathological and radiographic features

Atmospheric Deposition in Forest Ecosystem of Europe and Research of New Methods for Determination of Phosphorus and Ammonia Within a Framework of ICP Forests

U sklopu programa ICP Forests, provode se intenzivna i stalna motrenja stanja šumskih ekosustava Europe s posebnim osvrtom na atmosfer ska taloženja.Istražuju se nove metode određivanja pojedinih kemijskih ele menata zbog specifičnosti uzoraka. Fosfor i dušik su za biosferu elementi od najveće važnosti. Stoga je određivanje koncentracija fosfora i dušika od ne procjenjive važnosti u poznavanju, kontroli i modeliranju biokemijskih ciklusa šumskog ekosustava. U ovom radu ispitana je primjenjivost nove kolorimetrijske metode na au tomatskom analizatoru za određivanje fosfora i amonijakalnog dušika u uzor cima atmosferskih oborina, u svrhu unapređenja postojeće metodologije koja se koristi u ICP Forests, međunarodnom istraživačkom programu. Do sada korištene standardne metode određivanja fosfora i amonijakalnog dušika su metode spektrofotometrijske analize.U postupku validacije nove kolorimetrij ske metode na automatskom analizatoru primijenjeni su sljedeći kriteriji: gra fička analiza rezultata mjerenja, točnost, linearnost metode, radno područje metode, granica detekcije i granica kvantifikacije te ponovljivost. Rezultati odre đivanja pokazuju da je nova metoda određivanja fosfora i amonijakalnog du šika linearna u ispitivanom području, a t-testom je potvrđeno, da razlike re zultata određivanja pomoću dviju metoda određivanja fosfora i amonijakal nog dušika uz razinu pouzadnosti od 99,99 %, nisu značajne. Na osnovi kon trolnih karata te utvrđenih granica detekcije i kvantifikacije određenih novom metodom, utvrđena je dobra ponovljivost i veća osjetljivost nove me tode. Nova metoda određivanja može se s potpunom sigurnošću primijeniti u znan stveno-istraživačkom radu i biti dobra zamjena postojećim standardnim me todama. Ova metoda s potpunom sigurnošću će se moći primjenjivati u znanstve no-istraživačkom radu i ICP Forsets programu, jer je prilagođena upravo specifičnostima uzoraka uzetih iz šumskog ekosustava.The ICP Forests and EU Regulation aim to conduct intensive and continous monitoring on forests ecosystem as a means of evaluating the damage caused atmosferic pollution and other factors influencing forest con-dition.There is no doubt that phosphorus and nitrogen are among the most im portant elements for the biosphere and its biochemical cycles. Therefore, to get the most correct information about the concentration of different types of these elements is invaluable for understanding the control and creating bioc hemical cycles.In this work the implementation and validation of new colori metric method on automatic analyser for determination of phosphorus and ammonia has been investigeted. The investigation was performed on samples precipitated water in the forest ecosystem.Until now standard methods, spec trophotometry has been used for determination of phosphorus and ammonia.In the validation procedure following criteria have been investiga ted: graphical analyses of measured results, accuarcy, linearity in the working range, the limit of detection, the limit of quantification and the repeatability. The results showed that the method for determination of phosphorus and am monia on automatic analyser is linear in the range of investigation (Table 1), while the t-test has showed that differences between these two methods are not significant being 99,99 %. From the control charts it is obvious that the repeatability (Figure 7 and 8) of the results obtained with new method is good. The limit of detection and the limit of quantification shows more sensibility (Table 2). Therefore, the new method seem to be a good alternative to the standard methods and can be used in the scientific research of ICP Forests because is adapted to specifics of samples from forest

Heavy Metals in the Soil of the Kamenjak Public Institution

Javna ustanova Kamenjak nositelj je zaštićenih područja veoma važnih ekoloških (zaštitnih) i općekorisnih funkcija. Značajno povećanje negativnog antropogenog utjecaja, ponajviše u obliku korištenja motornih vozila, uvelike se odražava na sadržaj onečišćujućih tvari u tlu poput bakra (Cu), kadmija (Cd), olova (Pb), cinka (Zn), što potencijalno negativno može utjecati na čitav hranidbeni lanac, uključujući i ljudsko zdravlje. Uzimajući u obzir iznimnu važnost krajobraza kao zaštićenog područja u svakodnevnom životu ljudi, biljnog i životinjskog svijeta, cilj ovog istraživanja bio je utvrditi prisutnost navedenih teških metala i potencijalno toksičnih elemenata u tlu, njihove koncentracije te stupanj onečišćenja. Također, monitoring je uključivao i rekognosciranje terena, s naglaskom na biljne vrste koje su ujedno i indikatori ekoloških čimbenika te potencijalnih ekstremnih prilika. Istraživanje je provedeno na sveukupno 5 lokacija u periodu od svibnja 2018. do srpnja 2019. godine, uz naknadnu fizikalno-kemijsku analizu prikupljenih uzoraka tla unutar laboratorija Hrvatskog šumarskog instituta. Dobiveni rezultati u obliku povišene razine metala kadmija, cinka, uz nešto manju koncentraciju metala bakra i olova na većini lokaliteta, ukazuju na promjene ekoloških uvjeta te na važnost nastavka ovakvih oblika istraživanja u svrhu očuvanja i održivog korištenja ovog područja.Kamenjak Public institution is the holder of protected areas of very important natural unctions and ecosystem services. Significant increase in negative anthropogenic impact, mainly with the increasing number of motor vehicles during the summer months, is largely reflected in the content of soil pollutants such as copper (Cu), cadmium (Cd), lead (Pb) and zinc (Zn), which can potentially negatively affect the entire food chain, including human health. Considering the exceptional importance of landscape as a protected area in everyday life of people, flora and fauna, the aim of this study was to determine the presence of these heavy metals and potentially toxic elements in soil, their concentrations as well as contamination levels. The research was conducted at 5 localities in the period from May 2018 to July 2019. The field research included recording species that stand out for their cover abundance, with special emphasis on indicators with a certain habitat characteristic. Soil samples were collected on a monthly basis at depths of 0-5 cm and 5-10 cm. The analysed vegetation cover belongs to grassland vegetation habitat type in early succession phase. Also, some bioindicator species indicate extreme environmental conditions in the soil (pH) and former fires. The results obtained elevated levels of cadmium and zinc with slightly lower concentrations of copper and lead in most localities. This indicates changes of environmental conditions as well as the importance of continuing research for the purpose of conservation and sustainable use of this protected area

Epilithic diatoms in environmental bioindication and trout farm’s effects on ecological quality assessment of rivers

The main aim of this study was to investigate the application of benthic diatoms and the efficiency of diatom indices in water ecological assessment of rivers in Serbia, as well as the influence of trout farms on rivers water quality. Research was conducted in one year period along the Crnica and Radovanska rivers (Eastern Serbia), in 11 sampling sites (taking into account the position of trout fish farms that are built on both rivers). Results showed that fish farms affect the physical and chemical parameters, as well as diversity of the epilithic diatom assemblage along the rivers. Canonical correspondence analysis (CCA) indicated that among tested physical and chemical parameters, conductivity “EC”, water hardness “WH”, sulfates “SO42-”, ionized ammonia fraction “NH4+”, nitrates “NO3– “, “pH”, mud, stone and depth were the most important variables affecting the distribution of diatom species. A total of 206 epilithic diatom taxa were recorded in the Radovanska and 170 in the Crnica River. Based on diatom indices, trout fish farms have no significant negative impact on the water quality of the investigated rivers (indices are not enough sensitive). Redundancy analysis (RDA) showed a high degree of correlation between the majority of indices which mostly indicated to good water quality of studied rivers. TID and TDI were the only two indices indicating moderate and poor water quality of both rivers. Water quality based on the TIDRS, the first proposed diatom index for Serbia was differ in two classes in most sites compairing with TID