Vlianie na mancozeba vurhu reprodukciata na dugova pusturva (Oncorhynchus mykiss W.) i natrupvane na negovia kancerogenen metabolit etilen tiourea v ribnite produkti

Pesticides can be taken up from the water and accumulated in tissues of hydrobionts, often becoming multiplied thousands of times higher in the organism than in the surrounding water. The dithiocarbamate mancozeb is applied in plant protection as fungicide. In recent years the amount of mancozeb used in Europe significantly increased. It is carcinogen due to its metabolite - ethylene thiourea (ETU), which causes thyroid and pituitary tumors. The purpose of this study is to determinate the quantity of ethylene thiourea in products of rainbow trout (Oncorhynchus mykiss W.), reared in environment containing permissible, according to the European law, amount of mancozeb. Seeking an answer to the question: is this concentration limit really safe for the reproduction of rainbow trout and can the more toxic metabolite - ETU, be accumulated in the fish eggs and fillet and afterwards make them harmful to the consumers? The study included 3 stages: feeding, analysis of ethylene thiourea in fish eggs and fillet by a new developed and validated HPLC (high performance liquid chromatography) method and study of the reproductive indicators. The assays of ETU in all analyzed samples (fish and water) were below the limit of quantification of the method, 0.05 mg*l-1, so fish do not accumulate the carcinogen degradation product of mancozeb and the maximum residue level of mancozeb is really safe for the humans as consumers. But these environmental conditions caused reproductive disorders. They can be partly compensated by using sperm activation medium for artificial insemination of trout eggs, but successful fertilization does not guarantee successful hatching, especially of eggs in trout farms with presence of mancozeb in water, even in allowable concentration. The presented results confirm previous investigation, that Salmonidae are very sensitive fish species, react to the lowest deviations in concentration levels of xenobiotics and are used for indicator of non-polluted water.Pesticidite, popadnali vuv vodoemite, mogat da se poemat ot obitavashtite gi hidrobionti. Te sa v systoqnie da gi natrupat v svoite tukani i tiahnata koncetracia da se uvelichi, dori hiliadi puti, sravnena s tazi vuv vodata. Ditiokarbamatut mancozeb se prilaga v rastitelnata zashtita kato fungicide. Prez poslednite godini negovoto izpolzvano v Evropa kolichestvo znachitelno narasna. Kancerogennostta na mancozeba se dulji na metabolita mu, etilen tiourea (ETU), koiato prichiniava tumori na shtitovidnata jleza i hipofizata. Celta na tova izsledvane e da se opredeli sudurjanieto na etilen tiourea v produkti ot dugova pusturva (Oncorhynchus mykiss W.), otglejdana v sreda, sudurjashta dopustimo, suglasno evropejskoto zakonodatelstvo, kolichestvo mancozeb. Tursen e otgovor na vuprosa: tazi dopustima koncentracia naistina li e bezopasna za reprodukciata na dugovata pusturva i moje li da bude natrupan po-toksichniat metabolit - ETU, v haivera i fileto, koeto da gi napravi vredni za potrebitelite? Tova prouchvane vklyuchva 3 etapa: hranene, analiz na etilen tiourea v haiver i ribno file chrez novo razraboten i validiran HPLC (visokoefektivna techna khromatografia) metod i izsledvane na reproduktivnite indikatori. Kolichestvoto na ETU vuv vsichki analizirani probi (riba i voda) pokazaha sudurvanie pod granicata na kolichestveno opredeliane na metoda, 0.05 mg*l-1; ribata ne natrupva kancerogennia product na razgrajdane na mancozeba i maksimalno dopustimata mu koncentracia e naistina bezopasna za potrebitelite. Tezi uslovia na okolnata sreda obache prichiniavat reproduktivni razstroistva. Te mogat da budat chastichno kompensirani chrez izpolzvane na spermo-aktivacionna sreda za iskustveno osemeniavane na haiver ot pusturva. No uspeshnoto oplojdane ne garantira uspeshnoto izlyupvane, osobeno na haiver v pusturvovi stopanstva s nalichie na macozeb vuv vodata, dori v dopustimata koncentracia

Treatment of wastewater originating from aquaculture and biomass production in laboratory algae bioreactor using different carbon sources

The aim of present study was to explore the effect of different carbon sources on biomass accumulation in microalgae Nannochloropsis oculata and Tetraselmis chuii and their ability to remove N and P compounds during their cultivation in aquaculture wastewater. Microalgae cultivation was performed in laboratory bioreactor consisted from 500 mL Erlenmeyer flasks, containing 250 mL wastewater from semi closed recirculation aquaculture system. The cultures were maintained at room temperature (25-27ºC) on a fluorescent light with a light: dark photoperiod of 15 h: 9 h. The microalgae species were cultivated in wastewater with different carbon sources: glucose, lactose and saccharose. The growth of strains was checked for 96 h period. In the present study, N. oculata and T. chuii showed better growth in wastewater from aquaculture with saccharose carbon source during the experiment. The most effective reduce of nitrate and total nitrogen was proved in N. oculata cultivated in wastewater with glucose as carbon source. T. chuii cultivated in wastewater containing glucose showed 8.27% better cleaning effect in ammonium compared with N. oculata. T. chuii grew in wastewater with glucose as carbon source showed 19.5% better removal effect in phosphate compared with N. oculata strain

Treatment of wastewater originating from aquaculture and biomass production in laboratory algae bioreactor using different carbon sources

The aim of present study was to explore the effect of different carbon sources on biomass accumulation in microalgae Nannochloropsis oculata and Tetraselmis chuii and their ability to remove N and P compounds during their cultivation in aquaculture wastewater. Microalgae cultivation was performed in laboratory bioreactor consisted from 500 mL Erlenmeyer flasks, containing 250 mL wastewater from semi closed recirculation aquaculture system. The cultures were maintained at room temperature (25-27ºC) on a fluorescent light with a light: dark photoperiod of 15 h: 9 h. The microalgae species were cultivated in wastewater with different carbon sources: glucose, lactose and saccharose. The growth of strains was checked for 96 h period. In the present study, N. oculata and T. chuii showed better growth in wastewater from aquaculture with saccharose carbon source during the experiment. The most effective reduce of nitrate and total nitrogen was proved in N. oculata cultivated in wastewater with glucose as carbon source. T. chuii cultivated in wastewater containing glucose showed 8.27% better cleaning effect in ammonium compared with N. oculata. T. chuii grew in wastewater with glucose as carbon source showed 19.5% better removal effect in phosphate compared with N. oculata strain

Agro-ecological characterization of vermicomposted sewage sludge from municipal and poultry enterprise wastewater treatment plants

The purpose of this study was to make an agro-ecological characterization of vermicompost (VC) produced from sewage sludge (SS). As a substrate, SS from municipal and poultry meat processing enterprise wastewater treatment plants (MTP and PTP, respectively) was utilized. The substrates were vermicomposted by Red Californian earthworm (Lumbricus rubellus) for 120 days. For VC quality assessment, 19 physicochemical and 6 microbiological parameters were used. The evaluation of physicochemical parameters was done according to ISO standard methods and microbiological analysis-by plating 1 mL of sample dilutions on selective, chromogenic culture medium sheets. It was found that the vermicompost from MTP (VC-M) had higher levels of EC, mineral elements (N, P and K compounds in forms available to plants), heavy metals (Mn, Cu, Zn, Cr, Ni, Pb, Cd) and coliforms, and lower levels of pH, TOC, C/N ratio, Fe, total plate count (TPC), Enterobacteriaceae and Salmonella spp. counts compared to VC from PTP (VC-P). During the vermicomposting process, the substrates from both wastewater treatment plants (TPs) showed similar trends towards decrease in pH, TOC, N-NH4+, C/N ratio, TPC, coliforms, E. coli, Enterobacteriaceae and Salmonella spp. counts, whereas the opposite trends were established for EC, TKN, N-NO3-, TP, P2O5, TK, and K2O values. The vermicomposting had a negligible effect on heavy metal concentrations. In the final substrates E. coli were not detected, while the bacterial spore forms (Clostridium perfringens) were not eliminated. The final substrates cannot be used as fertilizers or soil amendments because of the presence of Salmonella spp. and C. perfringens over the permissible limits according to EU and Bulgarian regulations

Antimicrobial Resistance Distribution and Quorum-Sensing Regulation of Enterococcal Strains, Isolated from Hospitalized Patients

Background: Enterococci are intrinsically resistant/tolerant to various antimicrobial agents and can also acquire and combine different mechanisms of resistance, including quorum-sensing regulation, to most active compounds, which makes enterococcal infection treatment even more challenging. The aim of this study was to evaluate the pattern of antimicrobial resistance and to analyze the frequency of quorum-sensing asa1 and esp genes in clinical isolates representing the genus Enterococcus. Methods: Multiplex PCR assays were performed for the identification of 110 enterococcal isolates and the determination of their antibiotic susceptibility and the presence of asa1/esp genes. Additionally, the antibiotic resistance of the isolates was tested by the Kirby–Bauer disk diffusion method. Results: 90% of the isolates were identified as Enterococcus faecalis and 10% as Enterococcus faecium. Quorum-sensing regulation genes were present in 109 isolates. Aminoglycoside (aac(6′)/aph(2″)-, quinolone (emeA)-, β-lactams (TEM)-, and vancomycin (vanA)-resistance genes were detected in 108 isolates. All of the isolates tested were vanB negative. According to the Kirby–Bauer method, 39% of the isolates expressed multidrug resistance (MDR) and 33% of the MDR E. faecium were vancomycin-resistant. Conclusion: The large percentage of MDR enterococci possessing asa1/esp genes indicated a possible connection between quorum-sensing regulation and drug resistance. Therefore, the regular monitoring of the antimicrobial resistance of Enterococcus spp., and the identification of virulence factors are needed. It is also important to prevent host colonization through the elimination of factors leading to the expression of quorum-sensing genes

Antimicrobial Resistance Distribution and Quorum-Sensing Regulation of Enterococcal Strains, Isolated from Hospitalized Patients

Background: Enterococci are intrinsically resistant/tolerant to various antimicrobial agents and can also acquire and combine different mechanisms of resistance, including quorum-sensing regulation, to most active compounds, which makes enterococcal infection treatment even more challenging. The aim of this study was to evaluate the pattern of antimicrobial resistance and to analyze the frequency of quorum-sensing asa1 and esp genes in clinical isolates representing the genus Enterococcus. Methods: Multiplex PCR assays were performed for the identification of 110 enterococcal isolates and the determination of their antibiotic susceptibility and the presence of asa1/esp genes. Additionally, the antibiotic resistance of the isolates was tested by the Kirby–Bauer disk diffusion method. Results: 90% of the isolates were identified as Enterococcus faecalis and 10% as Enterococcus faecium. Quorum-sensing regulation genes were present in 109 isolates. Aminoglycoside (aac(6′)/aph(2″)-, quinolone (emeA)-, β-lactams (TEM)-, and vancomycin (vanA)-resistance genes were detected in 108 isolates. All of the isolates tested were vanB negative. According to the Kirby–Bauer method, 39% of the isolates expressed multidrug resistance (MDR) and 33% of the MDR E. faecium were vancomycin-resistant. Conclusion: The large percentage of MDR enterococci possessing asa1/esp genes indicated a possible connection between quorum-sensing regulation and drug resistance. Therefore, the regular monitoring of the antimicrobial resistance of Enterococcus spp., and the identification of virulence factors are needed. It is also important to prevent host colonization through the elimination of factors leading to the expression of quorum-sensing genes

Antifungal and Antioxidant Potential of Methanolic Extracts from Acorus calamus L., Chlorella vulgaris Beijerinck, Lemna minuta Kunth and Scenedesmus dimorphus (Turpin) Kützing

Plant extracts are an important alternative to antibiotics, which are ever more restricted because of their developing microbial resistance and some adverse effects that have been observed following frequent application. The aim of the present study was to determine the antifungal and antioxidant activity of the methanolic extracts of Acorus calamus, Chlorella vulgaris, Lemna minuta and Scenedesmus dimorphus. The antifungal activity of the extracts against strains of Aspergillus flavus, Aspergillus parasiticus, Aspergillus ochraceus, Aspergillus niger, Aspergillus carbonarius, Fusarium graminearum, Fusarium oxysporum, Penicillium chrysogenum and Alternaria alternata was evaluated via the agar well diffusion method. The antioxidant activity of the extracts was measured through the determination of three parameters—total phenolic content, total flavonoid content and radical scavenging potential (determined through UV/Vis analysis). A. calamus extracts had the highest antimicrobial activity against eight fungal strains, followed by the C. vulgaris, L. minuta and S. dimorphus extracts, which were inhibitory against two to three strains. Among the extracts from the species studied, the extract from S. dimorphus showed the highest antioxidant potential, as determined via the DPPH (1,1’-diphenyl-2-picrylhydrazil-radical) method. This correlated to its high total phenolic and flavonoid content. From A. calamus and L. minuta, methanolic extracts were obtained that exhibited similar values of the aforementioned parameters, followed by C. vulgaris extracts, which showed the lowest antioxidant activity. Based on the Pearson correlation coefficients, the impacts of the total phenolic content and the total flavonoid content on radical scavenging capacity are similar, and flavonoids were a significant part of the total phenolic compounds extracted from the plant materials studied

Comparative Study of Erythrocyte Sedimentation Rate after Aminoglycoside and Aminocyclitol Treatment in Goats (Capra hircus)

The aim of the present study was to follow up the erythrocyte sedimentation rate (ESR) in healthy female goats during and after 5-day parenteral treatment with amikacin (10 mg/kg), tobramycin (5 mg/kg), apramycin (20 mg/kg), gentamicin (4 mg/kg), kanamycin (10 mg/kg) and spectinomycin (20 mg/kg). Gentamicin and tobramycin caused an initial increase followed by a significant decrease of ESR on the 5th day for gentamicin and the 10th day for tobramycin, respectively, followed by recovery after the treatment. Reversely, amikacin and especially spectinomycin produced an increase of ESR without recovery several days post treatment. Kanamycin caused decrease of ESR on the 5th day without recovery in the subsequent days. Only apramycin did not give rise to increasing of ESR. In conclusion the aminoglycosides, especially tobramycin and gentamicin, caused more severe alterations of ESR than the aminocyclitols

Evaluation of the Anticancer and Probiotic Potential of Autochthonous (Wild) <i>Lacticaseibacillus paracasei</i> Strains from New Ecological Niches as a Possible Additive for Functional Dairy Foods

Probiotics such as Lactobacillus spp. could modulate the intestinal microbiota composition, supporting gastrointestinal tract barrier function and benefiting human health. To evaluate the anticancer and probiotic properties of potentially active autochthonous Lacticaseibacillus paracasei strains on proliferating and differentiated enterocytes, human colon adenocarcinoma cell line HT29 was used as a model. The lactic acid bacteria (LAB) were isolated from new ecological niches—mountain anthills populated by redwood ants (Formica rufa L.). Human colorectal adenocarcinoma cells (HT29, ATCC, HTB-38™) were treated for twenty-four hours with supernatants (SNs) derived from four strains of Lacticaseibacillus paracasei: P4, C8, C15 and M2.1. An MTT assay, alkaline phosphatase activity, IAP, Bax and Bcl-2 gene expression analysis (RT-qPCR) and the Bax/Bcl-2 ratio were evaluated. The MTT assay revealed that the observed effects varied among groups. However, 10% neutralized supernatants from P4, C8, C15 and M2.1 strains did not show cytotoxic effects. In contrast to non-differentiated cells, a significant (p p p p p p L. paracasei strains possess anticancer and probiotic properties and could be used as additives for functional dairy foods and thus benefit human health

An Assessment of Two Types of Industrially Produced Municipal Green Waste Compost by Quality Control Indices

Municipal green waste (MGW) has significantly increased with the development of urban green areas, and its utilization by composting is a good alternative to solve the problem. This paper presents the results from the quality assessment of two industrial composts (from the composting facility of a regional nonhazardous waste landfill) based on their physicochemical properties, hygienic safety (microbiological parameters), fertilizing potential (by fertilizing index, FI) and heavy metal polluting potential (by clean index, CI). Compost 1 (C1) was made from MGW (100%) and Compost 2 (C2) was made from MGW (75%) and discarded green peppers (25%). The evaluation of physicochemical parameters was conducted according to Bulgarian Standards (BDS) methods and microbiological analysis using selective, chromogenic detection systems. It was found that the EC, P, K, Mg, Cu, Cr and Ni were lower for C1 (p p E. coli were very low for both composts; presence of Salmonella was not detected. The estimated quality indexes (FI and CI) classified C1 as Class B compost (very-good-quality compost with medium fertilizing potential) and C2 as Class A compost (best-quality compost with high soil fertility potential and low heavy metal content). The C1 and C2 composts meet the requirements of EU and Bulgarian legislation and can be used as soil fertilizers