Acta Biologica Szegediensis
ISSN / EISSN : 1588-385X / 1588-4082
Published by: University of Szeged (10.14232)
Total articles ≅ 82
Latest articles in this journal
Acta Biologica Szegediensis, Volume 65, pp 47-57; https://doi.org/10.14232/abs.2021.1.47-57
This work aimed to evaluate the antimicrobial eﬀect of Ganoderma lucidum mycelial growth filtrates (MGF) on the phytopathogen Erysiphe diffusa and their potential eﬀects on the embryonic development of Gallus gallus. The antimicrobial activity was evaluated on E. diffusa spores by the microdilution broth method. To evaluate embryotoxic and teratogenic eﬀects, fertile eggs of G. gallus received injections of solutions containing the filtrates of G. lucidum through the air chamber. After three days of incubation, we opened the eggs and evaluated egg viability, embryo survival, malformation occurrence, embryonic staging and heart rate. Live embryos were prepared using whole mount technique and the morphological analysis was performed. We used the generalized linear model to fit embryotoxicity and teratogenicity data. We verified that G. lucidum MGF showed inhibitory activity in vitro against E. diffusa and the minimum inhibitory concentrations ranged from 5 to 10 mg/mL. We could also observe that the filtrates did not present embryotoxic or teratogenic eﬀects on the early embryonic development of G. gallus, but induced significant diﬀerences in the embryonic mean heart rate and on the stage of embryonic development.
Acta Biologica Szegediensis, Volume 65, pp 1-9; https://doi.org/10.14232/abs.2021.1.1-9
In this study, the eﬀect of mild (100 µM), moderate (300 µM) and severe (500 µM) nickel (NiSO4.7H2O) toxicity on the photosynthetic activity, photosynthetic pigment content and some antioxidant enzymes in the leaves of a barley cultivars (Hordeum vulgare L. cv. Tarm-92) was investigated. Moderate and severe nickel toxicity decreased root length while shoot length was not aﬀected by nickel stress, probably due to over accumulation of nickel in roots. Similarly, biomass accumulation was declined by moderate and severe nickel toxicity as reﬂected by the lowered fresh and dry weight. Chlorophyll a, chlorophyll b and consequently total chlorophyll content decreased by all nickel applications, presumably because the reduced level of carotenoids. Chlorophyll a ﬂuorescence measurements showed that nickel toxicity blocked electron movement in some speciﬁc points of the photosynthetic electron transport system. The constant Fo value indicated that PSII reaction centers was not damaged in the leaves of barley under nickel toxicity while the reduced Fm value showed that acceptor side of PSII was more sensitive to nickel toxicity as compared to donor side. Changes in JIP test parameters in the leaves of barley showed that primary photochemical reactions are reduced, and thermal dissipation of excess energy is increased. SOD and CAT activity is elevated in the leaves of barley under moderate and severe nickel toxicity which demonstrate an eﬃcient superoxide dismutation. Severe nickel toxicity, however, did not aﬀect SOD and CAT activity. The ascorbate-glutathione cycle was activated in the leaves of barley plants under nickel toxicity, probably indicating an eﬃcient H2O2 detoxiﬁcation. However, considerable H2O2 and MDA accumulation was observed in the leaves of barley under nickel stress. As a result, it may be concluded that the barley genotype Tarm-92 is moderately tolerant to nickel toxicity.
Acta Biologica Szegediensis, Volume 65, pp 17-27; https://doi.org/10.14232/abs.2021.1.17-27
The present study was undertaken to analyze diallel data using GGE biplot model to gather information about genetic interrelationships among parents and identiﬁcation of heterotic combinations for yield and yield components in bread wheat varieties. For this purpose, 8 bread wheat genotypes tested across in half-diallel crosses design, GGE biplot technique was used. Parents included the genotypes of Kouhdasht, Karim, Ehsan, Mehregan, N-92-9, Line 17, N80-19 and Atrak. The hybrids obtained from the one-way cross (28 hybrids) in agricultural years of 2016-17 were evaluated as randomized complete block design in two replications on the research farm of Gonbad Kavous University. The evaluated traits included the grain yield, weight of spike grains, number of grains in spike and number of spikes. Additive main eﬀects and genotype × environment interaction (GGE) were employed in the evaluation of genotypes; analyses showed signiﬁcant (P< 0.01) G × E, (genotype × environment interaction) with respect to plant seed yield. GGE biplot analysis showed that Karim was as the best general combiners for grain yield, number grain per spike and grain weight per spike, whereas Ehsan had the highest GCA eﬀects for number of spikes. Ehsan and Karim had higher speciﬁc combining ability than other genotypes. The studied genotypes for this trait were divided into two heterotic groups where the ﬁrst group included the genotypes of Kouhdasht, N-92-9, N80-19 and Atrak and the second group contained the genotypes of Line 17, Mehregan and Karim. Mehregan line had a weak combining ability with all testers and N-92-9 had also more power than others. Based on the biplot, the Karim genotype with high general adaptation was introduced as the ideal genotype in terms of grain yield, spike number, grain number per spike and grain weight, so the Karim genotype can be adapted to obtain high yield hybrids.
Acta Biologica Szegediensis, Volume 65, pp 35-45; https://doi.org/10.14232/abs.2021.1.35-45
Aeluropus from Poaceae comprises 5 species in the world and 3 species in Iran. This halophytic perennial is distributed in salty and dry soils of Asia, Europe, and Africa. In addition to being used as fodder, it can stabilize the soil by its rhizome or stolon. These features make Aeluropus a valuable plant. In this study, lemma and palea of 10 populations of Aeluropus were studied micromorphologically by scanning electron microscope (SEM) to determine diagnostic features among species studied. Eight characters as micro-prickle, macro-hair, long cell outline, cork and silica cells, papilla, salt gland, and epicuticular wax were studied. The occurrence of salt glands and silica cells in populations/taxa studied showed the ability of Aeluropus to tolerate harsh habitats. Our result showed the taxonomic value of ﬂoret micromorphological features to separate Aeluropus species.
Acta Biologica Szegediensis, Volume 65, pp 29-34; https://doi.org/10.14232/abs.2021.1.29-34
In addition to various medicinal properties, Acorus calamus (sweet ﬂag) is used in health, food, and perfume industries. Since this species is a rare plant in Iran, its propagation and cultivation are of the great importance. The aim of this study was to investigate the effects of different plant growth regulators on micropropaga-tion of this plant and to select the appropriate population. The root, the rhizome and the leaf explants of three populations (Arzefon, Pelesk, and Alandan) were cultured on MS medium supplemented with different concentrations of α-naphthalene acetic acid (NAA) and 6-benzylaminopurine (BAP) for callus induction and plant regeneration. The results showed that only rhizome explant resulted in direct plant regeneration. Among different treatments, the 1 mg/l treatment of BAP and NAA - with the highest mean number of regenerated plants (3.75 ± 0.85), the highest percentage of grown explants (91.6%) and maximum average length of regenerated plants (12.06 ± 0.32 cm) - was the best treatment for regeneration of sweet ﬂag. The highest mean number of root (6.6 ± 0.1) was observed in Alandan population in 1 mg/l treatment of indole-3-butyric acid (IBA). According to the present study, Alandan population is suitable for cultivation purposes in Iran.
Acta Biologica Szegediensis, Volume 65, pp 113-117; https://doi.org/10.14232/abs.2021.1.113-117
Persister cells are defi ned as a subpopulation of bacteria in a dormant state with the ability to reduce bacterial metabolism and they are involved in antibiotic tolerance. Toxin-antitoxin (TA) systems have been previously suggested as important players in persistence. Therefore, this study aimed to study the involvement of TA systems in persister cell formation in methicillin-resistant Staphylococcus aureus following antibiotic exposure. Using TADB and RASTA database, two type II TA systems including MazF/MazE and RelE/RelB were predicted in S. aureus. The presence of these TA genes was determined in 5 methicillin-resistant S. aureus isolates and the standard strain S. aureus subsp. aureus N315 using PCR method. To induce persistence, isolates were exposed to lethal doses of ciprofl oxacin and the expression of the studied TA system genes was measured after 5 h using Real-Time PCR. According to our results, all the studied isolates harbored the TA system genes. S. aureus was highly capable of persister cell formation following exposure to sub-MIC of ciprofl oxacin and RT-qPCR showed a signifi cant increase in the expression of the MazEF and RelBE loci, indicating their potential role in antibiotic tolerance. Considering the importance of antibiotic tolerance, further studies on persister cell formation and TA systems involved in this phenomenon are required to effi ciently target these systems.
Acta Biologica Szegediensis, Volume 65, pp 93-103; https://doi.org/10.14232/abs.2021.1.93-103
Cytochrome P450 monooxygenases (CYPs or P450s) are catalytically versatile hemoproteins, associated with drug metabolism, substrate utilization and pathogenesis. Mycobacterium ulcerans is a human pathogen causing Buruli ulcer. The study intended to investigate frequency and diversity of CYPs from M. ulcerans strains, understand the pan-CYPome clustering patterns and interconnection of CYPs using bioinformatics tools. M. ulcerans strains demonstrated the presence of 261 CYPs categorized into 35 families and 38 subfamilies. CYP138, CYP140, CYP189 and CYP125 were the ﬂourishing families. Around, 20 CYP families and 20 subfamilies were conserved. Flourishing and conserved CYP families/subfamilies were associated with lipid metabolism, substrate utilization etc. CYP140 had a role in pathogenesis. CYP279 was the least dominant family. CYP135, CYP183, CYP190, CYP271 and CYP276 were diagnostic markers for M. ulcerans subsp. shinshuense strain ATCC 33728 and M. ulcerans strain P7741. The pan-CYPome specified that M. ulcerans is evolving by gaining CYPs. CYP centric clustering revealed diversity and resemblances among M. ulcerans strains. More diverse nature of the M. ulcerans strain Harvey could be attributed to its larger size and geographical location. Co-occurrence network demonstrated mutual associations amongst substantial number of CYP families/subfamilies. This work provided comprehensive understanding of previously unexplored CYPs from M. ulcerans.
Acta Biologica Szegediensis, Volume 65, pp 75-84; https://doi.org/10.14232/abs.2021.1.75-84
Our aim was to map the gut region-specific diﬀerences of the mucosa-associated microbiome distribution in a streptozotocin-induced diabetic rat model. Tissue samples from the duodenum, ileum and colon were collected 10 weeks after the onset of hyperglycaemia to analyse the mucosa-associated microbiota using next-generation DNA sequencing. Striking diﬀerences were observed in the mucosa-associated microbiota of the duodenum between diabetic and control rats. A significant invasion of the aerobic genus Mycoplasma was apparent in diabetes, and the abundance of the anaerobic phylum Firmicutes decreased massively. It is noteworthy that insulin treatment eliminated the Mycoplasma invasion in the duodenum and apparently restored the anaerobic environment in the mucosa. In the ileum the abundance of the phylum Firmicutes increased in the diabetic samples. Although the proportion of the phylum Proteobacteria decreased moderately, its composition changed significantly, and insulin treatment induced only minor alterations. In the diabetic samples of colon, the abundance of the phylum Firmicutes decreased slightly, the relative number of the bacteria in the phylum Bacteroidetes increased strongly as compared to the control values, and after insulin treatment this increase was more significant. Chronic hyperglycaemia has the most prominent eﬀect on the mucosa-associated microbiota in the duodenum.
Acta Biologica Szegediensis, Volume 65, pp 85-92; https://doi.org/10.14232/abs.2021.1.85-92
Acinetobacter baumannii (A. baumannii) is an important nosocomial pathogen, which may be a causative agent in a wide-range of human pathologies. Carbapenems are usually considered the last safe and eﬀective choice of drugs for the treatment of Gram-negative infections. The emergence of carbapenem-resistant A. baumannii (CRAB) is a critical public health issue as they leave clinicians with limited therapeutic options. In this study, phenotypic methods were used to characterize sixty-two (n = 62) A. baumannii isolates, which were included based on their suspected non-susceptibility to meropenem. Minimum inhibitory concentrations (MICs) of meropenem, levofloxacin, gentamicin, sulfamethoxazole/trimethoprim, tigecycline were determined using E-tests, while colistin MICs were determined using broth microdilution. The isolates were subjected to the modiﬁed Hodge test (MHT), the modiﬁed carbapenem-inactivation method (mCIM) and the imipenem/EDTA combined disk test (CDT). Eﬄux pump overexpression was studied using agar plates containing phenylalanine-arginine β-naphthylamide (PAβN). Assessment of bioﬁlm-formation was carried out using the crystal violet tube-adherence method. 64.5% of the strains showed meropenem MICs in the resistant range (>8 mg/L), resistance rates were similarly high to the other tested antibiotics. The MHT and mCIM assay were positive in 79.0% and 67.7% of cases, respectively; the presence of an MBL was suggested for 29.0% of isolates. Eﬄux-pump overexpression was seen in 12.9% of isolates. 54.8% of the isolates were characterized as strong bioﬁlm-producers. Microbiology laboratories have an important role in diﬀerentiating the distinct mechanisms by which these pathogens develop the CRAB phenotype, as plasmid-borne carbapenemases are signiﬁcant from the standpoint of public health microbiology.
Acta Biologica Szegediensis, Volume 65, pp 59-64; https://doi.org/10.14232/abs.2021.1.59-64
The red spider mite, Oligonychus coffeae (Nietner) serves as a serious threat to the Darjeeling tea plantations affecting the quality of the leaves. Various plant extracts are currently being researched as an alternative to the chemical pesticides to control the red spider mites. In the present study, the leaves of Vitex negundo L. and the bulb of Allium sativum L. were analyzed for their acaricidal activity on the larval, nymphal and adult stages of the mite. Both the extracts were found to have potent activity against red spider mites and may prove to be potential acaricides in future.