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Creation of Turkiye risk map for Cydalima perspectalis (box tree moth) by weighted overlay analysis
(Selçuk Ünivesitesi, 2024) Yaman, Şule; Yaman, Mustafa
Boxwood (Buxus spp.), which is widespread all over the world except Antarctica and widely used in many areas, is threatened by Cydalima perspectalis (box tree moth). Cydalima perspectalis, which has become widespread in Europe, is a new invasive species originating from East Asia and has become widespread in Turkiye in the last ten years. This species was first observed in parks and gardens in Sar & imath;yer, Istanbul, in 2011. Since then, it has continued to spread rapidly in Turkiye. The pest causes intense damage by causing drying on boxwood areas, which causes economic and ecological losses. The rich ecological and topographical conditions of Turkiye are also favorable for the spread of this species. Therefore, it is important to develop pest control methods and take early measures. Within the scope of this study, the aim was to realize early detection of Cydalima perspectalis in Turkiye and make a risk map in this context. For this purpose, a risk map was created by determining the risky areas where Cydalima perspectalis can spread in Turkiye using weighted overlay analysis from geographic information system (GIS) technologies. Existing boxwood locations obtained from field studies were compared with the risk map and analyzed. As a result of the analysis, the presence of Cydalima perspectalis was found in the boxwood in the identified risk areas, and it is expected to be transmitted in boxwood that is in the risk area but not observed to have Cydalima perspectalis. With this research, a risk map for Cydalima perspectalis was made for the first time.
Antimicrobial resistance, multilocus sequence, and spa typing of staphylococcus aureus isolated from retail raw meat products
(Hindawi Ltd, 2022) Özdemir, Fatma
With a high capacity to acquire antimicrobial resistance, Staphylococcus aureus is an important pathogen causing severe infections in animals and humans. A total of 50 Staphylococcus aureus isolates from retail ground beef, chicken meat, and fish were characterized by antimicrobial resistance profiling, staphylococcal protein A gene (spa) typing, and multilocus sequence typing (MLST). The broth microdilution test results showed that all isolates were resistant to penicillin and sulphamethoxazole but had varying resistance rates to tetracycline (24%), erythromycin (4%), gentamicin (2%), ciprofloxacin (2%), trimethoprim (2%), and chloramphenicol (0%). The blaZ and sulI genes were detected in 100% of the isolates followed by grlA (94%), norA (92%), tetK (80%), chlA (60%), tetM (26%), aacA-aphD (2%), ermA (2%), fexA (0%), and dfrA (0%). Moreover, 26% of the isolates were multidrug-resistant, with five or more resistance genes. The spa typing analysis revealed 22 spa types, with t091 (16%), t1677 (8%), and t14538 (8%) being the most common, and one new spa type, t19851, was uncovered. MLST identified seven sequence types (STs), with ST7 (40%), ST15 (20%), and ST199 (13%) being the most common, and two STs (ST7435 and ST7436) were newly identified. In this study, S. aureus isolated from raw meat showed multidrug resistance and different clones associated with human infections. As a result, foods of animal origin may act as potential vehicles for transmission of multidrug-resistant S. aureus isolates, and the dissemination of potentially pathogenic clonal types, posing a health risk to humans.
In vitro culture and biological activity of Solanum dulcamara, a medicinal plant
(Georg Thieme Verlag Kg, 2007) Cansever, E.; Türker, A. U.
Solanum dulcamara L. (bittersweet) is a medicinal plant that has been used to treat skin diseases, warts, tumors, felons, arthritis, rheumatism, bronchial congestion, heart ailments, ulcerative colitis, eye inflammations, jaundice and pneumonia. A reliable in vitro culture protocol for bittersweet was established. Explants (leaf and petiole segments) were cultured on Murashige and Skoog minimal organics (MSMO) medium with various hormone combinations. Leaf explants formed more shoots than petiole explants. Best shoot proliferation was obtained from leaf explants with 3mg/l BA plus 0.5mg/l IAA and petiole explants with 3mg/l Kinetin plus 0.1mg/l 2,4-D. Regenerated shoots were transferred to rooting media containing different levels of IAA, IBA, NAA or 2,4-D. Most shoots developed roots on medium with 0,5mg/l IBA, 3mg/l IAA and 1mg/l IBA. Rooted plants were transferred to Magenta containers including vermiculate for acclimatization. After 3 weeks, they were transferred to soil. Biological activities of bittersweet extracts were assessed using selected bench-top bioassays (antibacterial and antitumor). Four different kinds of plant extracts were analyzed (IM, FM, IW and FW); methanolic extracts of in vitro-grown (IM) and field-grown (FM) plant materials and aqueous extract of in vitro-grown (IW) and field-grown (FW) plant materials. In general, methanolic extracts of field-grown leaves and stems were the most effective and showed antibacterial activity against Staphylococcus epidermidis, S. aureus, Klebsiella pneumonia, Salmonella typhimurium and Serratia marcescens. In vitro grown plant material showed less antibacterial activity than field grown plant material. All four extracts showed antitumor activity and the percentage inhibition was more than 40% in experiments comparing with control (water). Methanolic extracts showed better antitumor activity than water extracts and field-grown leaves and stems were better than in vitro-grown leaves and stems.
Distribution of non-marine ostracods in the streams of the Ceyhan River Basin (Turkey) and assessment of their indicator properties for water quality
(Akademiai Kiado Zrt, 2024) Yavuzatmaca, Mehmet; Çelekli, Abuzer; Dügel, Muzaffer; Lekesiz, Ömer
The potential of ostracod species as indicators of water quality and the influence of key ecological parameters on their distribution were evaluated by collecting samples from 39 streams during the spring, summer, and autumn seasons. Thirty-seven ostracod taxa (23 living, 14 subfossil) were identified, with Hemicypris anomala (Klie, 1938) being newly reported for Turkey. The summer season exhibited the highest diversity, indicated by the highest Shannon index value of 2.119, while the spring season showed the lowest diversity with a Shannon index value of 1.673. The variability in species composition was greater in the autumn than in other seasons. Among the nine factors affecting species distribution, the first three were found to be total nitrogen, magnesium, and elevation. Ilyocypris decipiens Masi, 1905 and Stenocypris intermedia Klie, 1932 indicated medium water quality in relation to the electrical conductivity, dissolved oxygen, total nitrogen and phosphorus. Stenocypris intermedia depicted waters of medium quality for biological oxygen demand and poor quality for nitrate. Ilyocypris monstrifica fi ca (Norman, 1862) signaled waters of good quality for total nitrogen and medium quality for dissolved oxygen. Potamocypris fallax Fox, 1967 and Potamocypris similis G.W. M & uuml;ller, 1912 characterized good and medium water quality regarding dissolved oxygen and total phosphorus, respectively. Cypridopsis vidua (O.F. M & uuml;ller, 1776) was identified fi ed as a positive-pollution indicator related to ammonium. The results suggest that ostracods have great potential as indicators of water quality, but more detailed studies on water quality parameters and ostracods are needed.
Comparative evaluation of Re 529-Bp sequence and B1 gene in the detection of toxoplasma gondii through PCR in water samples of Denizli, Turkey
(Springer Int Publ Ag, 2022) Güvendik, Tuğba Sağlam; Düşen, Serdar; Mete, Ergün; Karaman, Ülkü
Purpose While Toxoplasma gondii (T. gondii) infection is asymptomatic in immunocompetent individuals, it is a life-threatening protozoan in immunocompromised individuals. Its water-borne transmission to humans poses a serious public health concern. Polymerase Chain Reaction (PCR) has a considerable potential for the sensitive and specific detection of T. gondii oocysts in waters. Methods Comparative evaluation of RE 529-bp sequence and B1 gene to detect T. gondii tachyzoites and oocysts via PCR in agricultural irrigation water taken from downtown Denizli, Turkey and water samples collected from neighborhood fountains was performed for the first time in Turkish context. Results Based on real-time PCR targeting the B1 genetic markers and RE 529-bp sequence, T. gondii DNA was identified in 6 (16.7%) out of 48 samples collected from agricultural irrigation water. Besides, our PCR analysis did not establish any presence of T. gondii in drinking water samples. Conclusion T. gondii showed lower sensitivity in B1-based PCR than in PCR targeting RE 529-bp sequence.
Effect of nanoparticles on sugar beet cultured in vitro and its betalain and betaine production
(Tubitak Scientific & Technological Research Council Turkey, 2024) Alawad, Nour; Ünüvar, Ömer Can; Gürel, Songül; Okcu, Melih; Gürel, Ekrem
Sugar beet (Beta vulgaris L.) is considered one of the most important crops in terms of economics and food. With the widespread applications of nanoparticles (NPs) in plant science that have received great interest due to their amazing results and promising capabilities, the aim of this research was to investigate the effect of TiO2 and ZnO NPs on sugar beet plants cultured in vitro in several respects: seed germination, morphology, chlorophyll a and b contents, carotenoids, and the most important sugar beet metabolites, betaine and betalains. To investigate the effects, four different concentrations of NPs (0, 5, 15, and 25 mg/mL) were applied to two genotypes of sugar beet. Following the applications, germination numbers and root and hypocotyl lengths were measured. Further, chlorophyll, carotenoids, betaine, and betalains contents were estimated and compared. Plants exposed to NPs did not show a significant difference in seed germination, chlorophyll contents, or carotenoids as compared to the controls. On the other hand, betaine showed improvement at low concentrations of NPs and gradually decreased with increasing concentrations in both genotypes. Concerning betaxanthin, the monogerm genotype (SG833) showed a statistically significant increase in plants exposed to TiO2 NPs with concentrations of 15 and 25 mg/mL, while in the multigerm genotype (SG2020), a significant improvement was shown in plants exposed to ZnO NPs at concentrations of 15 and 25 mg/mL. Regarding betacyanin, it showed a statistically significant enhancement only in plants exposed to 25 mg/ mL ZnO NPs in the monogerm genotype. The effects of ZnO and TiO2 NPs at varying concentrations on sugar beet were studied. The research focused on the production of betaine and betalains, which are important secondary metabolites. The results indicated the possibility of increasing the production of these compounds while avoiding any negative or phytotoxic effects.
Description of a new species (Eucypris dorlionensis n. sp.) (Ostracoda, Crustacea) from Türkiye and a cladistic analysis of the genus Eucypris
(Tubitak Scientific & Technological Research Council Turkey, 2024) Batmaz, Filiz; Külköylüoğlu, Okan; Yavuzatmaca, Mehmet
This is the first clustering analysis of the 53 species of the genus Eucypris where we used 28 plesiomorphic and apomorphic character states in the Winclada/NONA program. Accordingly, Eucypris dorlionensis n. sp. was clustered within Group 2, in which the new species was clearly separated from the other species of the genus based on the shape of the carapace, presence of fine hair -like setae on the carapace surface, the position of the maximum height of the carapace, and length ratio of terminal claws of the second antenna. Eucypris dorlionensis n. sp. was collected from a trough in Eskisehir province in Turkiye where this is the first new species description of the genus that the number of species of the genus has now increased to 10. Besides, the genus is of cosmopolitan distribution known from a variety of aquatic bodies in the world. Including the new species, the number of the species has now raised to 56.
Near-resonant diurnal reactions: A physical model applicable to origin of life processes
(Tubitak Scientific & Technological Research Council Turkey, 2012) Budding, Edwin; Akı, Cüneyt; Demircan, Osman; Gündüz, Bülent; Gündüz, Güngör; Özel, Mehmet Emin
We adopt that the large residual chemical potential energy (CPE) among reagents of the biosphere constitutes the key physical problem posed by life. We associate the formation of this CPE with the near-resonant behaviour of a two-stage 'A-B' molecular process that behaves as a self-sustaining parametric oscillator. Under suitable conditions, such an oscillator generates CPE when forced by a periodic (daily) insolation. The net growth factor required to explain the current mean excess of biospheric CPE is similar to 5x10(-12) d(-1). This aligns with the mean exponential coefficient of secular oxygen generation in the terrestrial atmosphere. It is also consistent with a feasible scale of oxygen production in certain prebiotic natural photosynthesis scenarios, that can be candidates for the initial A subprocess on the Earth. We schematize initial evolutionary development of the A-B process, including the important role of the intermediate AB compound that provides negative feedback. Supportive C-type molecules also develop as a by-product. The diurnally related distribution of H2O2 on Mars may illustrate a comparable proto-biospheric scheme, and there may be analogous processes on Jupiter. The exponential growth in the lengths of terrestrial nucleotide chain molecules also supports its validity, as does the corresponding growth in measures of cellular complexity. We compare the scenario's implications with biological evidence on the possible co-evolution of blue-light photoreception and circadian timing in Archean photoautotrophs. We consider how a surviving level of cellular organization of circadian rhythmicity, from ancient through to modern times, may be interpreted along these lines, comparing our model with a previously published, comparable, biochemical one.
Possible effects of pliocene and pleistocene on the Anatolian populations of andricus tomentosus (Hymenoptera: Cynipidae)
(Univ Oradea Publ House, 2023) Mutun, Serap; Danso, Omar A.
Andricus tomentosus is an oak gall wasp species widely distributed in the Western Palearctic region and is one of the common parasitic species forming its bell-shaped asexual generation galls on white oak species. Despite its widespread distribution in Turkey, little is known about the species. In this study, we investigated 19 populations of A. tomentosus using partial sequences of the mitochondrial DNA cytochrome b gene and the nuclear ITS2 region to assess the species' genetic diversity and population genetic structure. Two hundred and forty sequences that generated 47 mitochondrial haplotypes and 28 nuclear alleles revealed intermediate to high genetic variation for both studied regions. Some eastern/southeastern Anatolian populations displayed higher diversity than the central/western localities. Demographic analyses and high haplotype/allele versus low nucleotide diversity implied that A. tomentosus populations might have undergone a series of expansion and retraction events in the past, which were correlated with the paleoclimatic and paleoenvironmental changes during Pliocene and Pleistocene. Further, phylogenetic inferences suggested that A. tomentosus populations were divided into two well-diverged clades as eastern and western, which offered that geographic barriers were also the main driver of the lineage formation in A. tomentosus.
Examination of posture and balance in children with primary monosymptomatic nocturnal enuresis
(Ios Press, 2023) İnal, Büşra; Özengin, Nuriye; Bakar, Yeşim; Ankaralı, Handan; Öztürk, Yusuf
PURPOSE: This study aimed to examine symptom severity, posture, and balance of children with primary monosymptomatic nocturnal enuresis (PMNE) and compare to a healthy control group. METHODS: Thirty-five children with PMNE and 34 healthy children were included in this study. Physical and sociodemographic characteristics of the children were recorded. Symptom severity was assessed with a Vancouver Non-Neurogenic Lower Urinary Tract Dysfunction/Dysfunctional Elimination Syndrome Questionnaire (NLUTD/DES), a four-day bladder diary and a seven-day bowel diary. Standing postural alignment was assessed with the Spinal Mouse device, and the sensory integration of static balance and dynamic standing balance was assessed with the Biodex Balance System SD. RESULTS: Compared to healthy controls, children with PMNE demonstrated increased symptom severity (p = 0.001), increased upright lumbar lordosis (p = 0.018) and sacral-hip angles (p = 0.029), decreased static balance in the sensory condition of unstable surface with eyes closed (p = 0.001), and decreased mediolateral dynamic balance (p = 0.049). CONCLUSION: Children with PMNE demonstrate altered postural alignment, static and dynamic postural instability, and greater symptom severity on the Vancouver NLUTD/DES than age-matched controls.
Determining diagnostic characteristics of the nonmarine Ostracoda (Crustacea) and their habitat selection with unique functional traits in the Kastamonu province (Türkiye)
(Elsevier GmbH, 2024) Külköylüoğlu, Okan; Yavuzatmaca, Mehmet; Tunoğlu, Cemal; Tunçkol, Bilge
Nonmarine ostracods are widely distributed in a variety of aquatic habitats, from mountain lakes to underground waters, where each species tends to show species-specific habitat preferences with unique functional traits to increase their survival chances. To understand the patterns of such a relationship between habitat preferences and functional traits of the species, 101 different aquatic sites in the Kastamonu province (Türkiye) were randomly sampled during August 2023. A total of 39 ostracods (20 species, 19 unnamed taxa) were encountered from 49 sites. Seventeen species are new reports for the province. Among them, six species are the most common species with cosmopolitan (or cosmoecious) characteristics. The contribution of these species to the diversity of alpha species (p < 0.05) was more than 90 %. The species with relatively high ecological tolerances generally unveiled low-optimum estimates. Canonical correspondence analysis explained 62.5 % of the correlation between environmental variables and species in which redox potential, electrical conductivity, calcium, and pH were found to be the most related variables to the species (p < 0.05). Fundiversity analysis showed that the presence of swimming setae was correlated with high values of functional diversity, functional richness, and functional distribution of species among five elevation ranges. The results of the habitat selection index and the standardized selection index coincided with the functional traits of the most common species. The species characterized by their habitat selection can be considered as diagnostic species of those specific habitats. Among them, Neglecandona neglecta, reported primarily from dams, springs, and troughs, is considered a typical diagnostic species of these habitats, while Cypridopsis vidua found in lakes and dams can be used as an indicator species for these types of lentic habitats. Similarly, three species (Heterocypris incongruens, Ilyocypris bradyi, Psychrodromus olivaceus) can play a critical role as diagnostic species in troughs but reporting them from different habitats such as ditches and rivers / lakes (I. bradyi) and dams (P. olivaceus and H. salina) indicated their wide range of habitat preferences. Hence, the results suggest that the occurrence of diagnostic species seems to correspond to certain habitat types and their functional traits. © 2024 Elsevier GmbH
Updates and improvements of Turkish Plants Data Service (TüBİVES)
(2011) Bakış, Yasin; Babaç, Mehmet Tekin; Uslu, Emel
Reaching biological information of the studied taxa became quite simple by introducing biodiversity information databases through internet. TüBİVES (Turkish Plants Data Service) is the first and the most efficient biodiversity database of the plants in Turkey. In this study, the structural of TüBİVES has been changed according to needs in new data types such as, chromosomal numbers, vernacular names, uses of plants, IUCN categories for endemics, nomenclature and synonym information of plants distributed in Turkey. The structure of database and querying algorithm have been updated both for TüRKNOM (Nomenclatural Database of Turkish Vascular Plants) and TüBİVES. © 2011 IEEE.
Last two hundred individuals: Rediscovery of scilla mesopotamia speta (Hyacinthaceae), a threatened endemic species in Turkey
(Polish Botanical Society, 2010) Eker, İsmail; Akan, Hasan
In this paper, the rediscovery of endemic and long missing species, Scilla mesopotamica Speta which had been only known from the type gathering, is given. The species has not been collected again after Sintenis in 1888, whose specimens served Speta for description of the new taxon. In 2004, the authors found it in a steppic rocky area, near Halfeti in Şanliurfa province, South East Anatolia, Turkey. After analyzing Sintenis' original collection notes, they concluded that this area is identical with the type locality. 5. mesopotamica has an extremely limited distribution and is represented by less than 200 specimens in the single known population that covers less than 50 m2. Taxonomy of the species, detailed description with illustrations, geographical distribution, habitat, ecology and status of IUCN extinction risk and some comments on conservation of the plant are also presented.
Optimization of morphological data in numerical taxonomy analysis using genetic algorithms feature selection method
(Association for Computing Machinery, 2009) Bakış, Yasin; Sezerman, Osman Uğur; Babaç, Mehmet Tekin; Meydan, Cem
Studies in Numerical Taxonomy are carried out by measuring characters as much as possible. The workload over scientists and labor to perform measurements will increase proportionally with the number of variables (or characters) to be used in the study. However, some part of the data may be irrelevant or sometimes meaningless. Here in this study, we introduce an algorithm to obtain a subset of data with minimum characters that can represent original data. Morphological characters were used in optimization of data by Genetic Algorithms Feature Selection method. The analyses were performed on an 18 character?11 taxa data matrix with standardized continuous characters. The analyses resulted in a minimum set of 2 characters, which means the original tree based on the complete data can also be constructed by those two characters. © 2009 Copyright is held by the author/owner(s).
Functional diversity and functional traits correlate ecology of nonmarine Ostracoda (Crustacea) at different elevational ranges
(E Schweizerbartsche Verlagsbuchhandlung, 2024) Külköylüoğlu, Okan; Yavuzatmaca, Mehmet; Özdilek, Ahmet; Tuncer, Alaettin
We tested how functional diversity (FD) along with its three components are correlated to ecological traits of nonmarine ostracods at seven elevational ranges from 800 to 1500 m. 38 ostracod taxa were collected from 55 aquatic sites in Aksaray province (Turkey). 21 species were new reports for the province. Shannon-Wiener diver-sity index indicated four cosmopolitans with more than 90 % of contribution. Results of the Canonical Correspond-ence Analysis (CCA) explained 76.8 % of the correlation between species and environmental variables. Salinity was the most effective variable on species. The highest functional divergence and functional richness were found in the elevational ranges of 800 - 899 m and 1100 -1199 m, respectively. When the highest functional evenness was accounted for the 1400 -1499 m, the functional dispersion was found higher in the range of 1200 -1299 m. A medium length of the carapace, the left valve overlaps the right valve, long swimming setae on the second antenna, a well-developed uropod, and a smooth carapace surface are the common traits of the species used in FD. Sampling sites were clustered by the common species, which also showed correlation with four cations (Ca, Na, Mg, K). Results suggest that 'functional diversity' can be used to correlate ostracod traits with their functional ecology.
Prevalence of Nosemosis and Varroosis in honey bees in Sinop province
(Kastamanu University, 2023) Yaman, Mustafa; Güvendik, Tuğba Sağlam; Ünal, Sabri
Abstract Aim of study: Sinop province has a potential to progress in beekeeping. In this study, it was aimed to investigate the presence and distribution of nosemosis and varroosis in honey bees in Sinop province. Area of study: 12 villages from 7 districts (Ayancık, Boyabat, Dikmen, Durağan, Erfelek, Gerze and Saraydüzü) in Sinop province were determined as study area. Material and methods: A total of 874 adult bee samples were dissected in Ringer’s solution and examined for nosemosis. A total of 1.640 adult bee samples were examined for varroosis. Main results: Nosemosis was the most common disease. Average of the nosemosis infection was 7.6%. On the other hand, varroosis was observed in the eight of 12 localities examined in Sinop province. Total infestation ranged from 0.6 to 8.2%. Highlights: Nosemosis and varroosis were observed in eight (66.7%) of the 12 examined localities in Sinop province. These data are considered as proof that honey production is negatively affected. This study also confirms that the beekeepers in the Sinop province should be informed in detail about the precautions to be taken in the monitoring and controlling varroosis and nosemosis.
Revealing genetic diversity of tulips in Turkey with inter-simple sequence repeat markers
(Springer, 2023) Hacıoğlu, Burcu Tarıkahya; Eker, İsmail
In order to reveal the genetic variation within the genus Tulipa, 57 accessions belonging to 19 taxa that are native to Turkey were examined in our study. With inter-simple sequence repeat markers, a matrix of 4332 data was obtained with 76 polymorphic bands. The unweighted pair group average (UPGMA) clustering algorithm was used for the Cluster Analysis. According to dendrogram, two main groups were formed: First group comprised of Tulipa sylvestris subsp. australis, Tulipa sprengeri, Tulipa humilis, Tulipa koyuncui, Tulipa undulatifolia var. undulatifolia and Tulipa julia accessions. Except Tulipa undulatifolia var. undulatifolia and Tulipa julia members of the first group belong to subgenus Eriostemones. In the subclades of the second main group the members of subgenus Tulipa and the members of subgenus Eriostemones were grouped in accordance to their subgenera. Our study is the first attempt to reveal the genetic diversity with all geographical distribution areas of Tulipa in Turkey. We think that the data given here will be useful for both plant taxonomists and ornamental plant breeders for future research.
Fritillaria ecerii (Liliaceae), a new species from Southeastern Anatolia, Turkey
(Finnish Zoological and Botanical Publishing Board, 2023) Eker, İsmail; Balos, Mehmet Maruf
Fritillaria ecerii Balos & Eker sp. nova (Liliaceae) is described from the province of Mardin, SE Anatolia, Turkey. It is morphologically similar to F. melananthera in having a striped perigone, to F. caucasica and F. baskilensis in having a long style, and to F. assyriaca in having the same number of leaves. However, it clearly differs from F. melananthera and F. assyriaca mainly by its smooth style, longer filaments and more numerous bracts, and from F. caucasica and F. baskilensis mainly by its striped perigone and more numerous bracts. Diagnostic characteristics, a description, images, and a conservation assessment are provided.
Comparative de novo transcriptome analysis and random UV mutagenesis: Application in high biomass and astaxanthin production enhancement for Haematococcus pluvialis
(Springer, 2023) Telli, Murat; Ünlü, Ercan Selçuk
BackgroundAstaxanthin is a natural carotenoid with strong antioxidant capacity. The high demand on astaxanthin by cosmetic, food, pharmaceutical and aquaculture industries promote its value in the biotechnological research. Haematococcus pluvialis Flotow 1844 has been characterized as one of the most promising species for natural astaxanthin biosynthesis. Even though H. pluvialis as an advantage in producing astaxanthin, its slow grow-yield limits usage of the species for large-scale production.Methods and ResultsIn this study we generated mutated H. pluvialis strain by using one-step random UV mutagenesis approach for higher biomass production in the green flagellated period and in turn higher astaxanthin accumulation in red stage per unit algae harvest. Isolated mutant strains were tested for the astaxanthin accumulation and yield of biomass. Among tested strains only mutant strain designated as only MT-3-7-2 showed a consistent and higher growth pattern, the rest had shown a fluctuated and then decreased growth rate than wild type. To demonstrate the phenotypical changes in MT-3-7-2 is associated with transcriptome, we carried out comparative analysis of transcriptome profiles between MT-3-7-2 and the wild type strains. De novo assembly was carried out to obtain the transcripts. Differential expression levels for the transcripts were evaluated by functional annotation analysis.ConclusionsData showed that increased biomass for the MT-3-7-2 strain was different from wild type with expression of transcripts upregulated in carbohydrate metabolism and downregulated in lipid metabolisms. Our data suggests a switching mechanism is enrolled between carbohydrate and lipid metabolism to regulate cell proliferation and stress responses.
A new ostracod species of the genus Xestoleberis from Nansen Island, Wilhelmina Bay, Southern Ocean, Antarctica
(Springer, 2023) Külköylüoğlu, Okan
Comparing to the ostracod studies on the other islands in the world, studies on the ostracod fauna of the islands in Antarctica are scarce. During the sixth Turkish Antarctica Expedition (TAE 6) to the islands (Dismal, Horseshoe, Nansen, Livingstone) in Western Antarctica, sediment and water samples were collected from 32 different water bodies (lakes, ponds, creeks, springs, littoral zones of sea). Among several new reports of different taxonomic groups which are under investigation, a new marine ostracod species (Xestoleberis nansenensis n. sp.) was encountered from Nansen Island. This is the first report of an ostracod from this island below 60 & DEG; S in Antarctica. The new species has several different features both in the carapace and soft body parts. Absence of ostracods from other islands sampled may be related to several a/biotic factors, such as water chemistry (e.g., relatively low calcium levels), extreme aquatic conditions (e.g., low-temperature values), improper habitat conditions (e.g., too little or absence of sediment in the water bodies), and isolation of the island(s) from the mainland. Although our new species is a marine form, comparative literature review indicated that there is no non-marine living ostracod species reported from the islands visited during the expedition. Possible reasons are discussed.

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