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Öğe Anatolian medicinal plants as potential antiviral agents: bridging traditional knowledge and modern science in the fight against COVID-19 and related viral infections(TUBITAK, 2024) Tilkat, Engin; Jahan, Israt; Hoşer, Ayşe; Kaplan, Alevcan; Özdemir, Oğuzhan; Onay, AhmetThe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was the cause of the coronavirus 2019 (COVID-19), commonly known as the coronavirus pandemic. Since December 2020, COVID-19 vaccines have been extensively administered in numerous countries. In addition to new antiviral medications, the treatment regimen encompasses symptom management. Despite sustained research efforts, the outbreak remains uncontrolled, with affected patients still lacking proper treatment. This review is a valuable asset for researchers and practitioners aiming to delve into the yet unexplored potential of Anatolian flora in the fight against COVID-19 and other viral infections. Numerous medicinal plants in Anatolia, such as thyme, sage, cannabis, oregano, licorice root, and Origanum sp., contain bioactive compounds with proven antiviral properties that have been used in the region for centuries. The rich legacy of traditional Anatolian medicine (TAM), has significantly influenced modern medicine; thus, the profusion of medicinal plants native to Anatolia holds promise for antiviral drug development, making this review essential for researchers and practitioners.Öğe EDI3 knockdown in ER-HER2+ breast cancer cells reduces tumor burden and improves survival in two mouse models of experimental metastasis(BioMed Central Ltd., 2024) Glotzbach, Annika; Rohlf, Katharina; Gonscharow, Anastasia; Lüke, Simon; Demirci, Özlem; Overbeck, Nina; Tibbe, Brigitte BegherBackground: Despite progress understanding the mechanisms underlying tumor spread, metastasis remains a clinical challenge. We identified the choline-producing glycerophosphodiesterase, EDI3 and reported its association with metastasis-free survival in endometrial cancer. We also observed that silencing EDI3 slowed cell migration and other cancer-relevant phenotypes in vitro. Recent work demonstrated high EDI3 expression in ER-HER2+ breast cancer compared to the other molecular subtypes. Silencing EDI3 in ER-HER2+ cells significantly reduced cell survival in vitro and decreased tumor growth in vivo. However, a role for EDI3 in tumor metastasis in this breast cancer subtype was not explored. Therefore, in the present work we investigate whether silencing EDI3 in ER-HER2+ breast cancer cell lines alters phenotypes linked to metastasis in vitro, and metastasis formation in vivo using mouse models of experimental metastasis. Methods: To inducibly silence EDI3, luciferase-expressing HCC1954 cells were transduced with lentiviral particles containing shRNA oligos targeting EDI3 under the control of doxycycline. The effect on cell migration, adhesion, colony formation and anoikis was determined in vitro, and significant findings were confirmed in a second ER-HER2+ cell line, SUM190PT. Doxycycline-induced HCC1954-luc shEDI3 cells were injected into the tail vein or peritoneum of immunodeficient mice to generate lung and peritoneal metastases, respectively and monitored using non-invasive bioluminescence imaging. Metabolite levels in cells and tumor tissue were analyzed using targeted mass spectrometry and MALDI mass spectrometry imaging (MALDI-MSI), respectively. Results: Inducibly silencing EDI3 reduced cell adhesion and colony formation, as well as increased susceptibility to anoikis in HCC1954-luc cells, which was confirmed in SUM190PT cells. No influence on cell migration was observed. Reduced luminescence was seen in lungs and peritoneum of mice injected with cells expressing less EDI3 after tail vein and intraperitoneal injection, respectively, indicative of reduced metastasis. Importantly, mice injected with EDI3-silenced cells survived longer. Closer analysis of the peritoneal organs revealed that silencing EDI3 had no effect on metastatic organotropism but instead reduced metastatic burden. Finally, metabolic analyses revealed significant changes in choline and glycerophospholipid metabolites in cells and in pancreatic metastases in vivo. Conclusions: Reduced metastasis upon silencing supports EDI3’s potential as a treatment target in metastasizing ER-HER2+ breast cancer.Öğe Biosynthesis, characterization, and biomedical applications of gold nanoparticles with cucurbita moschata duchesne ex poiret peel aqueous extracts(Mdpi, 2024) Kaval, Uğur; Hoşgören, HülyaIn this study, AuNPs were biosynthesized from Cucurbita moschata fruit peel extracts. Biosynthesized AuNPs exhibited maximum absorbance at a 555 nm wavelength, and XRD analysis indicated that the CM-AuNPs had a particle size of less than 100 nm and a cubic crystal structure. TEM scans revealed that the gold particles exhibited a spherical morphology, with an average size of 18.10 nm. FTIR analysis revealed strong peaks indicating the presence of functional groups involved in the reduction reactions. The surface charge of the biosynthesized AuNPs was determined to be -19.7 mV. The antibacterial and antifungal activities of AuNPs against pathogen strains were assessed by the minimum inhibitory concentration (MIC) method. The cytotoxic effects of CM-AuNPs on cancer cell lines (Sk-Ov-3, CaCo2, and A549) and healthy cell lines (HUVEC) were investigated using the MTT method. The findings indicated that AuNPs biosynthesized by the green synthesis method using C. moschata peel aqueous extract had high inhibition on the growth of pathogenic microorganisms and effective cytotoxic activity against cancerous cell lines at low doses. As a result, it can be concluded that CM-AuNPs will be eminently effective in the production of antibacterial and/or anticancer drugs in the pharmaceutical, food, and cosmetic industries.Öğe Phylogeny and biogeography of the family Cyprinidae in the Middle East inferred from cytochrome b DNA -: Evolutionary significance of this region(Academic Press Inc Elsevier Science, 2002) Durand, J.D.; Tsigenopoulos, C.S.; Ünlü, E.; Berrebi, P.The phylogenetic relationships of cyprinid species from the Middle East and neighboring biogeographical areas were investigated using cytochrome b sequence variation in order to test hypotheses that consider the Middle Eastern area as an important interchange area or a center of speciation for the freshwater fauna. A total of fit cyprinid species were analyzed over the complete cytochrome b fragment (1140 bp); 28 belong to the Leuciscinae subfamily and 34 to the Cyprininae. All the Leuciscinae lineage fish recorded in the Middle East are also found in Europe, which was interpreted as an important Palearctic influence in the Middle Eastern ichthyofauna consistent with the Lago Mare dispersion. However, it has also been suggested that several Danube species have their origins in the Middle East. In contrast, the Cyprininae subfamily showed three highly divergent lineages, one shared with the Euro-Mediterranean area (Barbus/Luciobarbus genus) relict of the Lago Mare dispersion, one shared with Africa (Carasobarbus/Varacorhinus subgenus), and the third shared with Asia (Garra genus). Furthermore, clades observed in the phylogenetic reconstructions are not consistent with morphometric or karyological data and disagree with previous taxonomic assumptions. Lastly, the dispersion history in the Middle East of this subfamily appears much more complicated and ancient than that of the Leuciscinae. However, taking into account Cyprininae and Leuciscinae distribution, the Middle East appears more like an important interchange area for the freshwater ichtyofauna than a center of speciation. (C) 2002 Elsevier Science.Öğe Effect of starch induced bacterial growth and amylase production in bacillus subtilis(Wiley-V C H Verlag Gmbh, 1995) Ensari, N.Y.; Otludil, B.; Aytekin, M.C.The amylases produced by a Bacillus subtilis were purified from three different media which occurred nonstarch, starched and after eight hours shocked by starch media. Purified enzymes were compared each other Km, purification steps, thermal stability, pH and bacterial growth. In shocked medium, bacterial growth and amylase production are much more than in starched medium. The enzyme was stable at 65 degrees C in three media. Km values were found different in three media where maltose inhibited the amylase activity. This inhibition is a competitive inhibition.Öğe Levels of transaminases, alkaline phosphatase, and protein in tissues of clarias gariepienus fingerlings exposed to sublethal concentrations of cadmium chloride(Wiley, 2008) Velmurugan, Babu; Selvanayagam, Mariadoss; Cengiz, Elif I.; Uysal, ErsinThe freshwater fish, Clarias gariepienus fingerlings, were exposed to sublethal concentrations (1.7 and 3.4 mg/L) of cadmium chloride for 12 days. Aspartate aminotransferase (AAT), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and total protein levels were assayed in the gill, brain, and muscle of the fish at regular intervals of 6 and 12 days. The activities of AAT, ALT, and ALP of the treated fishes increased significantly in all the tissues compared with the control fish. Protein level in all the tissues showed a significant decrease in comparison to unexposed controls throughout the experimental periods. These results revealed that cadmium chloride effects the intermediary metabolism of C. gariepienus fingerlings and that the assayed enzymes can work as good biomarkers of contamination. (C) 2008 Wiley Periodicals, Inc. Environ Toxicol 23: 672-678, 2008.Öğe Production, purification, and characterization of thermostable ?-amylase from thermophilic Geobacillus stearothermophilus(Wiley-V C H Verlag Gmbh, 2014) Fincan, Sema Agüloğlu; Enez, BarışThe -amylase (-1-4-D-glucan glucanohydrolase; EC 3.2.1.1) secreted by Geobacillus stearotermophilus was purified and characterized. Maximum enzyme production was achieved after 24h cultivation at pH 7.0 and 55 degrees C. The enzyme was active in a broad temperature range, between 50 and 80 degrees C, with an optimum at 70 degrees C; and maximum activity was at pH 7.0. The enzyme was purified using 80% ammonium sulfate precipitation, dialysis, Sephadex G-100 gel filtration, and DEAE-cellulose column chromatography, with a 46-fold and 65% recovery and showed a MW of 63kDa by SDS-PAGE. It was determined that the purified enzyme was stable at 50 and 60 degrees C, and pH 7.0. It was determined that the purified enzyme was stable at 50 and 60 degrees C at the end of 2h. The enzyme retained 100% activity pH 7.0 at the end of 3h. The enzyme was activated by Ca2+, Mn2+, and Triton X-100, but strongly inhibited by Cu2+, Zn2+, Fe2+, and Hg2+. The enzyme follows Michaelis-Menten kinetics with K-m and V-max values of 0.051mM and 1.424mol/min, respectively.Öğe The antimicrobial activity of essential oils of Hypericum scabrum, Hypericum scabroides and Hypericum triquetrifolium(Wiley, 2004) Kızıl, Göksel; Toker, Zuhal; Özen, Hasan Çetin; Aytekin, ÇetinThe essential oils of Hypericum scabrum, Hypericum scabroides and Hypericum triquetrifolium were studied for the first time for their antimicrobial activity against nine organisms. All the essential oils exhibited some broad spectrum antibacterial activity, at a concentration of 80 mug/mL. The essential oils of Hypericum species showed antibacterial activity against the tested organisms and a yeast. Copyright (C) 2004 John Wiley Sons, Ltd.Öğe Water quality assessment and apportionment of pollution sources of Tigris River (Turkey) using multivariate statistical techniques-a case study(Wiley, 2012) Varol, M.; Gökot, B.; Bekleyen, A.; Şen, B.The Tigris is one of the most important transboundary rivers in western Asia and originates in the Toros mountains of the Eastern Anatolia region of Turkey. Multivariate statistical techniques, such as cluster analysis (CA), principal component analysis (PCA) and factor analysis (FA), were applied for the evaluation of temporal/spatial variations and the interpretation of a water quality data set for the Tigris River, which was obtained during 1?year of monitoring. This study presents the usefulness of multivariate statistical techniques for the evaluation and interpretation of complex water quality data sets and apportionment of pollution sources/factors to obtain better information about water quality and the design of a monitoring network for the effective management of water resources. Hierarchical CA grouped 12?months into two periods (the first and second periods) and classified seven monitoring sites into three groups, that is, less polluted sites, medium polluted sites and highly polluted sites, based on similarities in the water quality characteristics. PCA/FA identified five factors in the data structure, which explained 77.5% of the total variance of the data set. This allowed us to group the selected parameters according to common features and to evaluate the influence of each group on the overall variation in water quality. Varifactors obtained from the factor analysis indicated that the parameters responsible for water quality variation were mainly related to soluble salts (natural), organic pollution and nutrients (anthropogenic). Copyright (C) 2011 John Wiley & Sons, Ltd.Öğe Evaluation of the taxonomy and conservation status of Podonosma sintenisii (Boraginaceae)(Nature Research Centre, 2024) Kaya, Ömer Faruk; Ertekin, Alaattin SelçukThe current taxonomic status of an endemic species, Podonosma sintenisii, is discussed, and its morphology is compared with that of the closely related species Podonosma orientalis. Nutlet, leaf, and pollen micrograp-hs of the species are presented using scanning electron microscopy. The identification key and geographical distribution map of Podonosma sintenisii and related species are presented, and the threat category is defined according to IUCN.Öğe The new records of the Rose-Ringed Parakeet alexandrinus krameri (Scopoli, 1769) from the province of Diyarbakır, Türkiye(Pleiades Publishing, 2024) Karakaş, RecepAbstract: The Rose-ringed Parakeet Alexandrinus krameri (Scopoli, 1769) firstly reported from Diyarbakır province, South-eastern Anatolia, Türkiye. The species have been identified in three different locations in Diyarbakır and totally, nine individuals have been determined between January 2021 and June 2022 periods. The records and observations of species were evaluated for the occurrence of species together with available data. Although no breeding has been detected so far, there are suitable habitats in Diyarbakır that will enable the species to breeding and establishing a new population. The species may be seen more widely in the near future due to the fact that the species is settled in the neighbouring provinces to the Diyarbakır. Rose-ringed Parakeet records were evaluated for Diyarbakır province where is species newly reported. This may allow us to estimate changes in population size and range expansion of species in this part of Türkiye in the future. Monitoring of the species is recommended to predict future effects of it on local fauna in this part of Türkiye.Öğe A new record of three-band garden slug ambigolimax valentianus (A. Férussac, 1822) (Gastropoda: Limacidae) from Turkey(Turkiye Klinikleri Journal of Medical Sciences, 2018) Ekin, İhsan; Şeşen, RıdvanAmbigolimax valentianus (A. Férussac, 1822), the three-band garden slug, is originally native to the Iberian Peninsula (Spain, Portugal, and the Balearic Islands); however, it has been spread by human activities to many other parts of the world. There is no distributional record of the slug in Turkey to date. The species was recorded for the first time in Turkey during a biological survey carried out in the accommodation area of Dicle University (Diyarbakır) in October 2017. Some of the slugs were transferred to the laboratory for their morphological determination and dissection. Notably, more than 50 species of slugs dwell on Turkish lands and most of them are distributed in the Northern Anatolia Region. A. valentianus is observed here for the first time on Turkish lands. The purpose of the study is to present the first record of A. valentianus in Turkey and contribute to the checklist of Turkish gastropods.Öğe Biomarkers of environmental pollutants(Hindawi Publishing Corporation, 2014) Kaviraj, Anilava; Ünlü, Erhan; Gupta, Abhik; El Nemr, AhmedThousands of pollutants enter daily into environment and exert various kinds of stress on organisms and ecosystems. Risk assessment of these pollutants to organisms and ecosystems is challenging because of diversities in chemical nature and mode of toxicity of the pollutants as well as variation in sensitivities of the organisms exposed to the pollutants. Even low, relatively innocuous concentrations of pollutants often produce deleterious effects on organisms, which are difficult to be predicted, because measurable effects are expressed only after prolonged exposure. But it may be too late to take remedial actions or steps to reduce risk when these incipient effects are expressed. Therefore, it is necessary to develop early warning signals or biomarkers that convincingly reflect adverse biological responses towards anthropogenic environmental toxins even at minute concentrations.Öğe Investigation of the fatty acid contents of edible snails Helix lucorum, Eobania vermiculata and non-edible slug Limax flavus(ACG Publications, 2017) Ekin, İhsan; Şeşen, RıdvanThe purpose of this work is to reveal the fatty acid composition of phospholipids, neutral and total lipid content of edible land snails Helix lucorum, Eobania vermiculata and non-edible land slug Limax flavus (Gastropoda: Pulmonata). The analyses revealed that the snails and slug are rich in C16:0, C18:0, C18:1ω9 and C18:2ω6 acids. Phospholipid fractions contained very high amounts of C20:4ω6 (15.37% in H. lucorum, 12.37% in E. vermiculata and 8.59% in L. flavus) which is the most important precursor of eicosanoids. The level of ΣPUFA, in edible snails, was found to be higher than ΣSFA and ΣMUFA. However, in the slug, ΣMUFA level was higher than ΣSFA and ΣPUFA levels in neutral and total lipid contents. Ʃω6 / Ʃω3 (Omega 6 / Omega 3) ratio was defined to be very high in the phospholipid of H. lucorum, E. vermiculata and L. flavus; 6.07, 8.29 and 5.39, respectively. Furthermore, the study showed that all three species are valuable sources of omega 6 and essential fatty acids; C18:2ω6 and C18:3ω6.Öğe Birds of Mount Nemrut National Park Area, Turkey(Verlag der Oesterreichischen Akademie der, 2018) Karakaş, Recep; Biricik, MuratBird species diversity at Mount Nemrut (Adıyaman province, south-eastern Turkey) and in the surrounding areas was studied during the period 2009–2010. Data was collected using the point-count method at predefined observation sites. Birds of 107 different species were recorded, of which 20 were certainly breeding, 17 were probably breeding, and 29 were possibly breeding in the study area. Including species reported by other sources, a total of 160 bird species has so far been detected in the Mount Nemrut area, while the white-throated dipper was recorded for the first time. Diversity was calculated by using the Shannon-Wiener diversity index. Highest diversities were detected in woodland habitats (including oak groves), rocky areas and woodland habitats. Bird diversity showed peaks corresponding to spring and autumn passage migrations, and bird numbers were highest in mid-winter. Although part of Mount Nemrut has been declared one of Turkey’s key biodiversity areas and has already been given the status of a National Park, threats occur, notably the harmful effects of mass tourism and illegal hunting, because of ineffective protection measures. Better knowledge of local avifauna and its habitat requirements may help to ensure better protection of this unique area.Öğe Variations in the fatty acid compositions of the liver and gonad tissue of spiny eel (Mastacembelus mastacembelus) from Atatürk Dam Lake(Turkish Biochemistry Society, 2017) Kaçar, Semra; Başhan, MehmetObjective: The aim of the study was to investigate quantitative and qualitative fatty acid profiles of the gonad and liver tissue of female Mastacembelus mastacembelus (spiny eel). Methods: Total lipids were extracted with 5 mL of chloroform-methanol (2:1 v/v). Samples containing gonad and liver lipid were transesterified with acidified methanol. The fatty acid methyl esters were extracted with hexane. Fatty acids were detected by gas chromatography (GC). Results: The major saturated fatty acids (SFAs) were myristic acid (C14:0), palmitic acid (C16:0) and stearic acid (C18:0) in both gonad and liver tissue. Oleic acid (C18:1 ω-9) and palmitoleic acid (C16:1 ω-7) were the prominent monounsaturated fatty acid (MUFA). The dominant polyunsaturated fatty acids (PUFAs) were linoleic acid (LA, C18:2 ω-6), arachidonic acid (AA, C20:4 ω-6), docosapentaenoic acid (C22:5 ω-3) and docoesahexaenoic acid (DHA, C22:6 ω-3). The ratio of ω-3/ω-6 ranged from 1.55 to 3.44 and 1.18 to 2.71 in the gonad and liver tissue, respectively. Conclusion: The findings of this study will be useful for understanding the seasonal distribution of fatty acid composition in the liver and gonad of spiny eel.Öğe Elicitors enhanced the production of bioactive compounds in shoot cultures of Hypericum amblysepalum(Institute of Botany and Botanical Garden "Jevremovac", University of, 2023) Asan, Hilal SurmuşIn this study, we examined the effects of elicitors MeJA (Methyl jasmonate) and JA (Jasmonic acid) (50, 100, and 200 µM) on the growth and production of 15 phenolic compounds in shoot cultures of Hypericum amblysepalum using the LC-MS/MS method. The biomass production increased on shoots elicited with 50 µM JA and MeJA. However, higher concentrations of these elicitors had a negative effect on the growth of the shoot cultures, while simultaneously resulting in an increase in the secondary metabolite content. The elicitor MeJA (especially 200 µM MeJA) was more effective in terms of increasing the phenolic compound contents. The highest amounts of rutin (2.8 fold), astragalin (2.4 fold), protocatechuic acid (2.4 fold), hesperidin (2 fold), pseudohypericin (1.9 fold), chlorogenic acid (1.4 fold), and hypericin (1.9 fold) were obtained from the shoots elicited with MeJA (200 µM). In addition, the application of elicitor JA 200 µM increased the amount of luteolin (2 fold), quercitrin (1.9 fold), apigetrin (4 fold), apigenin (2.9 fold), and hyperoside (1.3 fold). The current study revealed that specific secondary plant metabolites can be regulated by exogenous elicitors in shoot cultures of H. ambysepalum, thus highlighting their promise as a very valuable source of raw materials for the pharmaceutical industry.Öğe Recombination provides evidence for ancient hybridisation in the Silene aegyptiaca (Caryophyllaceae) complex(Springer Verlag, 2017) Pfeil, Bernard E.; Toprak, Zeynep; Oxelman, BengtRecombination events among distinct alleles complicate phylogenetic estimation. Various in vivo and in vitro processes can bring distinct alleles into the same genome to then undergo recombination, which may subsequently mislead phylogenetic inference if not assessed properly. Among the processes bringing divergent alleles together, hybridisation is perhaps the simplest and most likely, but alternatives need to be considered before hybridisation can be accepted as the underlying cause. Such alternatives include the presence of paralogues or deeply coalescing alleles, as well as amplification artefacts. Here, we document a recombination event that apparently took place between two divergent lineages of the Silene aegyptiaca complex in the flowering plant family Caryophyllaceae. We evaluate several possible mechanisms that might be responsible for the observed pattern. An ancient introgressive hybridisation event was the simplest explanation for the observations, compatible with geographic proximity of the affected lineages, whereas paralogy and deep coalescence are difficult to reconcile with the evidence obtained from a species tree of the group based on six different, non-recombinant genes and gene trees inferred using two partitions of the recombinant locus.Öğe Enhanced production of anticancer triterpenoids in optimized Pistacia lentiscus L. callus cultures via methyl jasmonate and silver nitrate elicitation(Elsevier B.V., 2023) Tilkat, Engin; Süzerer, Veysel; Asan, Hilal Surmuş; Ertaş, Abdulselam; Demir, Elif; Yılmaz, Mustafa Abdullah; Hoşer, Ayşe; Onay, AhmetPistacia lentiscus L. is a traditional medicinal plant from the Mediterranean region with a long history of use. Elicitor-based strategies have proven effective in enhancing the production of secondary metabolites (SMs) with therapeutic potential in callus cultures. In addition, optimizing callus cultures is crucial for the synthesis and stability of SMs production. In this study, we have successfully established practical and optimized callus cultures from the leaves and roots of the mastic tree. Full-strength Murashige and Skoog (MS) medium gave the highest callus growth, with the combination of 2,4-dichlorophenoxyacetic acid and kinetin (each at 1 mg/l) giving the most favourable results for both explant types (80 % and 84 % callus induction, respectively). Optimal culture conditions were determined to be a sucrose concentration of 15 g/l, a pH of 5.8, a temperature of 25 °C and light intensities of 20 μmol m−2 s−1 for roots and 80 μmol m−2 s−1 for leaves. It is interesting to note that methyl jasmonate (MeJA) positively affected callus biomass, whereas silver nitrate (AgNO3) had the opposite effect. Elicitation with AgNO3 and MeJA significantly enhanced the biosynthesis of anticancer triterpenoids, particularly ursonic acid (UA), ursolic acid (ULA), masticadienolic acid (MDLA), and oleanonic acid (ONNA). Liquid Chromatography-Mass Spectrometry (LC-MS/MS) analysis revealed a remarkable 26.71-fold and 3.4-fold increase in UA content in leaf and root calli treated with AgNO3, respectively. It is noteworthy that ULA, MDLA and ONNA were not present prior to elicitation but were detected after elicitation. The accumulation of anticancer triterpenoids in callus cultures generated from various P. lentiscus L. explants is first demonstrated in our research. In addition, this research demonstrates a structured methodology for the enhancement of the accumulation of anticancer triterpenoids during callus culture.Öğe Adsorption performance of Bacillus licheniformis sp. bacteria isolated from the soil of the Tigris River on mercury in aqueous solutions(Taylor and Francis Ltd., 2022) Baran, Mehmet Fırat; Yıldırım, Ayfer; Acay, Hilal; Keskin, Cumali; Aygün, HüsamettinMercury is known to be one of the most toxic heavy metals in the environment and is released into the water systems in significant quantities through natural events and industrial process activities. Many chemical materials are used as adsorbents in the removal of toxic metals from the environment and wastewaters. However, using microorganisms as bio-sorbents instead of chemical materials has become common recently due to their low cost, easy availability and presence in nature. In this study, Bacillus licheniformis in the soil isolated from the Tigris River was used as bio-sorbent. The mercury (Hg(II)) absorption behaviour of Bacillus licheniformis bacteria (BLB) was investigated using inductively coupled plasma mass spectrometry. The effects of equilibrium of adsorption time, temperature, adsorbent dosage and pH on the adsorption of Hg (II) onto BLB were determined. The maximum adsorption capacity of Hg (II) onto BLB was determined as 82.12 mg/g (T = 25°C, pH 5, Co = 50 mg/L, m = 25 mg). The BLB was characterised using Fourier transform infrared spectroscopy analysis, thermal gravimetric analysis/differential thermal analysis, scanning electron microscopy analysis and energy-dispersive X-ray spectroscopy analysis. In addition, pseudo-first-order and pseudo-second-order kinetic models were applied. The equilibrium data for the adsorption of Hg(II) onto BLB were examined by the Langmuir and Freundlich isotherm models. The activation energy was calculated using the pseudo-second-order rate constant. These results suggested the BLB can be used as an efficient adsorbent for the removal of Hg(II) metal ions from wastewater. When the results of bio-sorption studies were examined, it was found that the bio-sorbent could be reused easily. The present study suggests that microorganism bio-sorbents are useful for the efficient removal of mercury from aqueous solutions.
