Studia Universitatis Babeş-Bolyai Biologia
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Contributions to the knowledge of amphipod fauna (Crustacea, Amphipoda) from the Danube Delta, Romania
No full textThe amphipod species Pontogammarus maeoticus (Sovinskij, 1894) was identified in two locations from the Danube Delta, Romania (Sfântu Gheorghe and Sulina beaches) in July 2019. This is an eurybiont species, able to withstand high salinity variations characteristic to mixing fresh and sea waters. The individuals presented a special character in their morphology, a depression on the basis of pereiopod V. The present paper contributes to the knowledge of existing amphipod fauna from the Danube Delta, in the Black Sea coast area.
Purcari et al sc (PDF)
Article history: Received 8 April 2020; Revised 7 December 2020; Accepted 10 December 2020; Available online 20 December 2020
Last meal: food composition of road-killed Lacerta viridis (Reptilia: Lacertidae) from Romania
No full textFood composition of road-killed Lacerta viridis was studied on 41 individuals from the scientific collection of the University of Oradea, Romania. They were collected from different roads in the country between 1998-2019. All lizards had stomach contents. Although in most cases the stomach contents were partially digested, the preys could be identified at a taxonomical level comparable with the one achieved in other lizard feeding studies. The analysed L. viridis individuals had consumed 275 preys, which belong to 25 taxa, as well as inorganic elements and vegetal remains. The most important preys were Orthoptera, Araneidae and Coleoptera. The differences in lizards` food composition according to geographic origin were not significant. Our results confirm that this species food composition can be studied on road killed individuals, but also proves the uniformity of its food, at least in the Balkan Peninsula.
Maier et al (PDF
Pseudomonas aeruginosa at the dawn of a post-antibiotic era: clinical significance, resistance mechanisms, novel antibiotics and alternative treatments
No full textSince their discovery, antibiotics have helped treat diseases prior to which many were untreatable, saving millions of lives. However, due to the overuse of antibiotics in medicine and agriculture, the advent of resistant strains of bacteria followed shortly after. The current antibiotic resistance crisis is bringing humanity closer to a post-antibiotic era, when all the advancements made by modern medicine could easily be reversed. Pseudomonas aeruginosa is a Gram-negative, rod-shaped bacterium, ubiquitous owing to its minimal nutritional and growth requirements. P. aeruginosa is one of the pathogens included in the priority list of the WHO, being assessed as critical due to its high antimicrobial resistance, leaving only a few effective treatment options to combat it. As an opportunistic pathogen, P. aeruginosa establishes infection in immunocompromised patients, primarily in hospital settings. In order to initiate infection, it requires several virulence factors that mediate the invasion of the pathogen into host cells. Owing to the multiple resistance mechanisms of P. aeruginosa, it has developed resistance to most classes of antibiotics. Due to its increased resistance, treating P. aeruginosa infections is a great challenge for clinicians. Several β-lactam/β-lactamase combinations have been approved and are available as treatment options, which overall show high efficacy against P. aeruginosa. Moreover, novel antibiotics are currently in development as possible antipseudomonal agents, including a Pseudomonas-specific formulation. In addition, new strategies such as bacteriophage therapy, pyocins or the inhibition of the quorum sensing system are being investigated for the treatment of P. aeruginosa infections.
Kovacs et Jakab (PDF)
Article history: Received 8 September 2020; Revised 11 November 2020; Accepted 3 December 2020; Available online 20 December 202
Microbial activity in soils from the Făgăraș Mountains
No full textThe aim of this paper was to assess the microbial activity and detection of some enzymes from soils of mountain zones in order to understand the complex processes that occur in these habitats. The sampling sites are located in three zones from the Făgăraș Mountains (woodside, forest and grassland). Six soil samples from these zones were subjected to microbiological and enzymological studies. The physical-chemical analyses were carried out using a portable multiparameter (pH, Eh, electrical conductivity and salinity). The following four ecophysiological bacterial groups have been studied: aerobic mesophilic heterotrophs, ammonifiers, nitrifiers and denitrifiers. The presence of all ecophysiological bacterial groups was registered in all the soil samples. The studied bacterial groups present fluctuations according with the sampling zones. The descending ranking of their abundance in the soil samples was: aerobic mesophilic heterotrophs, ammonifiers, nitrifiers, denitrifiers. Based on the bacteria number of each ecophysiological group, the bacterial indicators of soil quality (BISQ) were calculated. All of the four enzymatic activities analysed in soils (phosphatase, catalase, actual and potential dehydrogenase) were registered at every sampling site. Based on the absolute values of enzymatic activities, the enzymatic indicator of soil quality (EISQ) was obtained. The EISQ and BISQ values indicate a good intensity of these activities in all the analysed zones.
Culda et al (PDF
12TH CONFERENCE ON HALOPHILIC MICROORGANISMS “HALOPHILES 2019”, 24‐28 JUNE 2019, CLUJ‐NAPOCA
No full text12TH CONFERENCE ON HALOPHILIC MICROORGANISMS “HALOPHILES 2019”, 24‐28 JUNE 2019, CLUJ‐NAPOCA: BOOK OF ABSTRACTS.
Studia UBB Biologia 64_1_2019 (PDF
Growth and development of salinity-exposed rice (Oryza sativa) rhizo-inoculated with Bacillus subtilis under different pH levels
No full textThe study investigated the effects of varying pH levels on the growth and development of salt-exposed rice (Oryza sativa L.) after inoculation with Bacillus subtilis. Germinated rice seedlings (var. FARO 44) were sown in garden soils amended to 100 mM NaCl, and were thereafter inoculated with Bacillus subtilis. The transplants were subsequently exposed to periodic wetting with 5 mL of pH-buffered water (pH 3, 5, 7, 9 and 11) every day, and with 5 mL of 100 mM NaCl every 4 days. The set up was monitored during a 30-day period. Results showed significant reduction in chlorophyll a and b as well as lycopene and tocopherol contents of leaves due to changes in the lipid-to-protein ratio of pigment-protein complex or increased chlorophyllase activity and drought stress. There were improved morphological characteristics such as plant height, sheath and foliar dimensions due to inoculation of B. subtilis. Increase in salinity resulted in a decrease in plant height, leaf length and sheath. Inoculation not only promoted rice growth, but also enhanced rice tolerance towards salinity owing to the fact that FARO 44 is a salinity-tolerant rice variety. A better understanding of the interaction between microbial inoculants and soil conditions is required to harness the desired benefits towards improving crop development.
Igiebor et al (PDF
Chlorophyll a measurement as an index of phytoplankton bloom and primary production in the Gulf of Guinea, Nigeria, West Africa
No full textChlorophyll a levels of oceanic waters in Nigeria located in the Gulf of Guinea and adjoining water bodies were investigated in this study. Sample collections were done at quarterly intervals from March 2014 to January 2015 from fifty-five sites and spanned over eight coastal states. Integrated water sample for chlorophyll analysis was taken from a depth of 10m to the surface using a silicone hose. Determination of chlorophyll was done by a combination of filtration, extraction, homogenization, centrifugation and spectrophotometry using the trichromatic method. The range of chlorophyll a concentration was 27.5 – 1419.35 µgL-1 in oceanic waters and 32.79 – 1649.64 µgL-1 in adjoining water bodies. Chlorophyll a concentrations varied spatially and temporally, with a general observation of higher concentrations in the south-west oceanic locations in the Bight of Benin axis of the Gulf of Guinea, compared to the south-south oceanic locations in the Bight of Bonny axis of the Gulf of Guinea In the adjoining coastal waters, the Gbaji River in Badagry, Lagos, located in the South-West, had the highest overall total chlorophyll a concentration while the Brass River in Bayelsa, located in the South-South had the lowest overall total chlorophyll a concentration throughout the study period. The mean primary production, ranging from 439.85 µgL-1 to 1051.89 µgL-1, were included in six categories of <500 µgL-1; 600-699 µgL-1; 700-799 µgL-1; 800-899 µgL-1; 900-999 µgL-1 and >1000 µgL-1. Principal component analysis showed strong positive correlations of chlorophyll a with total biomass of major phytoplankton groups (Bacillariophyta, Dinophyta and Cyanophyta) and dissolved oxygen levels; negative correlation of chlorophyll a with Fe, NO3, PO4, TDS, SiO3 and turbidity.
Kadiri et al (PDF
The relation between natural and sexual selection – study case on the phenotypic characteristics that influence mate choice in a North-West Romanian human population
No full textThe force of sexual selection acts upon the mating process of all beings, this great force is influenced by different factors as phenotypic characteristics. Related to mate choice, in humans, recent studies have shown that, along with eye color, hair color is considered a relevant physical trait (Frost, 2006). Thereby, the purpose of this study is to reveal how these two factors influence mate choice by analyzing the hair color preference of a small population from Romania. Additionally, we explore how different types of selection influence each other and assume that both contribute in choosing a partner. In order to obtain basic data, a socio-demographic survey was addressed to adult male and female individuals. Based on their answers, disregarding the gender, a considerable number of individuals are brown-haired, as we expected from this area of the globe. Among the results obtained, the following considerations are worth mentioning: the most common hair color in Romania is brown, individuals with this trait are considered the most attractive for the opposite sex and parents’ hair color represents a predictor for future partners. These preferences are both in concordance and in contrast with natural selection. However, much more research is needed, approaching other areas such as genetics and forensics to determine how all these mechanisms, as well as others, affect the process of mating.
Popa-Cordun et Stermin (PDF
Ultrastructural aspects of Eriogaster catax and Eriogaster lanestris (Lepidoptera: Lasiocampidae)
No full textEriogaster catax (Linnaeus, 1758) and E. lanestris (Linnaeus, 1758) are two related species in the family Lasiocampidae with decreasing distribution areas and extremely isolated populations, thus being vulnerable to numerous threats, particularly human impact. Until presently, the biological and ecological studies regarding the species in question are scarce, particularly for E. catax, a species protected through Annexes II and IV of the Council Directive 92/43/EEC, Annex II of the Bern Convention and Law no. 49/2011 in Romania. Taking into account the importance of the E. catax species and the insufficient information reported on the ecological need of the species, a highly detailed analysis at an ultrastructural level could provide valuable information. The primitive aspect of the wings explained the weak distribution of adults. The different flight period of adults and egg laying season were reflected on the structure, adherence and size of eggs. Also, the structure of the fibers was correlated with the different ways in which E. catax and E. lanestris use the nest.
Sitar et Ciorita (PDF
Effects of vegetation and water seasonal variation on habitat use of herons (Aves, Ardeidae) in Tonga Lake (North-East Algeria)
No full textThe present study was aimed to determine the effect of some environmental factors such as water features and vegetation cover on the distribution and habitat use of herons over different seasons of the bird’s life (breeding, passage and wintering) in Tonga Lake (North East Algeria) from March 2017 to February 2018. We used remote sensing techniques to study the environmental factors variations, we adopted the normalized difference vegetation index (NDVI) to give an estimate of vegetation cover and we used the normalized difference water index (NDWI) to study the water features. In our study, we determine that the abundance and richness of herons species is largely influenced by the water features and vegetation cover. The seasonal variations in the amount of these environmental factors are known to affect the availability of various food items for herons. Eight species of herons were identified during the study period. Pearson’s Correlation Coefficient was used to examine the effect of NDVI and NDWI on the distribution of herons. The results showed that the NDVI was significantly positively correlated with richness and abundance of herons respectively (r=0.728, p<0.05) (r=0.651, p<0.05), whereas the NDWI was significantly negatively correlated with the richness and abundance of herons (r=-0.65, p<0.05) (r=-0.69, p<0.05) respectively.
Chettibi et al (PDF