Nutrient Medium Research Articles

Glutathione-Mediated Metal Tolerance in an Amphibian Chytrid Fungus (Batrachochytrium dendrobatidis).

The spread of the amphibian chytrid fungus Batrachochytrium dendrobatidis, which causes the disease chytridiomycosis, has resulted in amphibian declines and extinctions worldwide. Some susceptible amphibian species can persist in contaminated habitats, prompting the hypothesis that B. dendrobatidis might be sensitive to heavy metals. We tested a panel of 12 metals to rank their toxicity to B. dendrobatidis zoospores and zoosporangia during a 6-h exposure. To better understand the mechanism for metal detoxification, we also evaluated whether glutathione is required for metal tolerance by depleting cellular glutathione before metal exposure. In addition, we investigated whether prior exposure to low metal concentrations impacted tolerance of subsequent exposure, as well as identifying metal combinations that may act synergistically. Silver (Ag), cadmium (Cd), and copper (Cu) were particularly toxic to B. dendrobatidis, with zoospore minimum lethal concentration values of 0.01 mM (Ag), 0.025 mM (Cd), and 0.5 mM (Cu). These three metals along with zinc (Zn) were also inhibitory to zoosporangia, with minimum inhibitory concentration values of 0.005 mM (Ag), 0.04 mM (Cd), 0.075 mM (Cu), and 0.04 mM (Zn). The fungicidal effects of several metals was reduced when assays were conducted in nutrient medium compared with synthetic pond water, highlighting the need for careful in vitro assay design and interpretation. Glutathione depletion strongly influenced tolerance of Cd and Ag (85% and 75% less growth, respectively) and moderately influenced tolerance of Cu, Zn, and lead (37%, 18%, and 14% less growth, respectively), indicating the importance of glutathione for metal detoxification. In general, the minimum metal concentrations that inhibited growth of B. dendrobatidis far exceeded values detected in contaminated amphibian habitats in Australia, suggesting that metal contamination alone may not have a strong protective effect against chytridiomycosis. We discuss future research directions to futher understand the potential for dissolved metals to create chytrid refuges. Environ Toxicol Chem 2024;00:1-9. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Biological activity of probiotic microorganisms depending on cultivation conditions

Metabiotics, a new generation of probiotics based on biologically active components (metabolites), are currently the subject of interest and study in the scientific community. This is a more advanced and promising form of probiotic preparations, among the properties of which high bioavailability, safety, and 'versatility in use are especially noted. The article presents a study of the antagonistic activity and biofilm formation of opportunistic strains of microorganisms under the influence of metabolites of probiotic microorganisms grown on 'various nutrient media and in different physical states. The objectives posed during the study answer questions about the biological activity of probiotic microorganisms grown on different nutrient media and in various physical states. The data obtained will form the basis for further research of active components that allow obtaining a clinical effect and will also help formulate an approach to developing the most effective ready-made forms of metabiotics. The place of research is the microbiological laboratory of the Testing Center of the Testing Laboratory Complex of the Federal State Budgetary Educational Institution of Higher Education Novosibirsk State Agrarian University.

EFFECT OF PROBIOTIC TREATMENT ON THE MICROBIOLOGICAL ACTIVITY OF UKRAINIAN TYPICAL BLACK SOIL

The search for novel substances that promote the establishment of a microbial community and facilitate optimal humification processes while increasing soil organic matter content offers an opportunity for land restoration. The objective of study was to determine the abundance of ecological and trophic groups of soil microorganisms and the intensity of microbiological processes when subjected to probiotic treatment at various concentrations and doses in typical black soil. The eco-trophic groups of soil microorganisms were identified by inoculating dilutions of soil suspensions onto selective nutrient media. The direction and intensity of soil microbiological processes were assessed using the mineralization-immobilization, oligotrophy, and pedotrophy indexes. The results demonstrate that probiotics has a positive impact on the microbiological activity of the soil, leading to an increase in the number of ecological and trophic groups of soil microorganisms during both spring and autumn seasons. Notably, a significant effect on the soil microorganism conditions was observed after 30 days of probiotic treatment. Probiotics exhibit a favorable influence on microbiological processes within the soil, fostering conducive conditions for the development of soil microorganisms and the formation of humus. The most effective concentration of probiotics for promoting the functionality of microbial communities in black soils is determined to be 10%, accompanied by a dose of 100 l ha-1. Consequently, the application of probiotic treatment at a concentration of 10% and a dose of 100 l/ha-1 holds the potential to enhance the biological state of the soil, restore soil microbial diversity, and serve as an environmentally safe fertilizer.

Metagenomic evaluation of peanut rhizosphere microbiome from the farms of Saurashtra regions of Gujarat, India

The narrow zone of soil around the plant roots with maximum microbial activity termed as rhizosphere. Rhizospheric bacteria promote the plant growth directly or indirectly by providing the nutrients and producing antimicrobial compounds. In this study, the rhizospheric microbiota of peanut plants was characterized from different farms using an Illumina-based partial 16S rRNA gene sequencing to evaluate microbial diversity and identify the core microbiome through culture-independent (CI) approach. Further, all rhizospheric bacteria that could grow on various nutrient media were identified, and the diversity of those microbes through culture-dependent method (CD) was then directly compared with their CI counterparts. The microbial population profiles showed a significant correlation with organic carbon and concentration of phosphate, manganese, and potassium in the rhizospheric soil. Genera like Sphingomicrobium, Actinoplanes, Aureimonas _A, Chryseobacterium, members from Sphingomonadaceae, Burkholderiaceae, Pseudomonadaceae, Enterobacteriaceae family, and Bacilli class were found in the core microbiome of peanut plants. As expected, the current study demonstrated more bacterial diversity in the CI method. However, a higher number of sequence variants were exclusively present in the CD approach compared to the number of sequence variants shared between both approaches. These CD-exclusive variants belonged to organisms that are more typically found in soil. Overall, this study portrayed the changes in the rhizospheric microbiota of peanuts in different rhizospheric soil and environmental conditions and gave an idea about core microbiome of peanut plant and comparative bacterial diversity identified through both approaches.

Joint Impacts of Meloidogyne incognita and Soil Nutrition on Solanum lycopersicum var. cerasiforme.

Strategies for plant nutrient resource allocation under Meloidogyne spp. infection and different soil nutrient conditions are not well established. In response, the objectives of this research are to determine if increased vegetative growth of Solanum lycopersicon var. cerasiforme (cherry tomato) under high nutrition enhances resistance to M. incognita and whether adaptive strategies for growth, reproduction, and nutrient uptake by cherry tomato infected with M. incognita alter nutrient availability. The study was conducted under greenhouse conditions using high, medium, and low soil nutrient regimes. The research results indicate that the total biomass of cherry tomato was less in the presence of M. incognita infection under all three nutrient conditions, compared with plants grown in the absence of this nematode. However, the increase in the root/shoot ratio indicates that cherry tomato allocated more resources to belowground organs. Under the combined impacts of M. incognita infection and low or medium soil nutrition, the nitrogen content in root system tissues and the phosphorus content in shoot system tissues were increased to meet the nutrient requirements of galled root tissue and plant fruit production. It is suggested that plants increase the allocation of reproductive resources to fruits by improving phosphorus transportation to the aboveground reproductive tissues under low and medium nutrient conditions. Overall, the study highlights a significant impact of soil nutrient levels on the growth and resource allocation associated with M. incognita-infected cherry tomato. In response, soil nutrient management is another practice for reducing the impacts of plant-parasitic nematodes on crop production.

Instigation of neurosporaxanthin from Rhodococcus ruber O16N isolated from Gulf of Khambhat

Compounds of natural origin are in burgeoning demand driven by heightened awareness of their health benefits. We present the maiden study on the production of neurosporaxanthin, a carotenoid, from marine Rhodococcus ruber O16N. Analysing various physical parameters including carbon source, agitation speed, temperature, salt and pH, we found that agitation adversely affects biomass and carotenoid production. Isolate O16N grew well, when medium was supplemented with mannitol or sorbitol, CaCl2, at pH 6 and best carotenoid production was observed when sorbitol or fructose and CaCl2 was supplemented in media at pH 7 at 37 °C in static condition with the maximum carotenoid yield of 1097 mg/L, whopping 18-fold more as compared to nutrient medium. Furthermore, thorough characterisation identified the produced carotenoid as neurosporoxanthin. These findings highlight the potential of marine Rhodococcus ruber O16N as a valuable source for neurosporaxanthin production and emphasise the importance of optimising physical parameters for maximising carotenoid yield.

Detection of <i>M. tuberculosis</i> Using Cartridge-Based Technology in Patients with Negative Sputum Microscopy Results in a Regional Laboratory

The objective: to evaluate results of M. tuberculosis detection and testing drug susceptibility to rifampicin using molecular genetic methods in tuberculosis patients with a negative sputum smear microscopy result.Subjects and Methods. Pulmonary tuberculosis patients registered in Arkhangelsk Region from 2016 to 2020 were enrolled in the study; those patients were notified as new cases and relapses with a negative sputum smear microscopy result before treatment and had results of molecular genetic testing (MGT) (Xpert MTB/RIF MTB/RIF) and BACTEC MGIT 960 available.Results. 479 people (40%) were registered as pulmonary tuberculosis cases with a negative sputum smear microscopy result. MGT was performed in 327 (68%) patients. A positive result of MGT was received in 120 (37%) patients, a positive result of BACTEC MGIT 960 was received in 165 (50%) people. Concordance of results was observed in 70% of cases. In 136 (41%) people, both tests did not detect Mycobacterium tuberculosis, in 95 (29%) both tests showed a positive result. Discrepancies between the results of two tests were observed in 30% of cases. In 71 (22%) cases, culture growth was observed in BACTEC MGIT 960 with negative results of MGT. In 8% of cases, DNA of Mycobacterium tuberculosis was detected, but there was no culture growth on the nutrient medium. 43/120 (36%) cases of resistance to rifampicin were detected. The median time from sputum collection to initiation of MDR-TB treatment based on sputum MGT results made 18 (IQR 10–29) days. Molecular genetic testing makes it possible to promptly detect the majority of TB patients with a negative sputum smear result, and reduce the time for drug susceptibility testing, which allows this testing to be used as the first test when examining for pulmonary TB.

Скринінг продуцентів протеаз серед представників роду Bacillus, ізольованих з прибережної зони Кінбурнської коси

Protease-producing representatives of Bacillus have been isolated from various environments such as the rhizosphere, soil, sewage, food, waste, and saline environments (sea water, marine sediments, hypersaline lakes, salty food, soda lakes, etc.). However, today, little is known about the characteristics of proteases in representatives of the genus Bacillus, isolated from the coastal and aquatic environments. In this regard, the purpose of this work was to screen for the presence of different types of proteolytic activity in Bacillus cultures isolated from the coastal zone of the Kinburn split. Methods. The objects of the study were 15 cultures (L1-L15), isolated from the dry grass of the coastal zone of the Kinburn spit (Mykolaiv region). The cultures were grown under conditions of deep cultivation at 28 °С, with a mixing speed of the nutrient medium of 230 rpm for 2 days. Methods of determining proteolytic (caseinolytic, elastolytic, fibrinolytic, fibrinogenolytic, and collagenase) activity in the culture liquid supernatant were used. Results. Study of the spectrum of proteolytic activities of 15 strains of Bacillus sp. showed that L9, L1, L2 and L4 exhibited higher levels of proteolytic activity compared to the other strains tested. Bacillus sp. L9 and L2 showed the highest elastase activity (35.80 and 33.80 U/mL, respectively), L1, L2, and L4 − fibrinogenolytic (12.50, 11.20 and 10.33 U/mL, respectively), and L1 and L4 − fibrinolytic (13.00 and 10.90 U/mL, respectively) activity. Conclusions. According to its catalytic properties, a number of representatives of Bacillus sp. isolated from the dry grass of the coastal zone of the Kinburn split may be promising for further research as producers of enzymes with elastotic, fibrinolytic, and fibrinogenolytic activities.

Assessment of Cow Urine as a Nutrient Medium for Indoor Cultivation of Spirulina sp.

This study aims to explore the feasibility of utilizing cow urine as an economical alternative nutrient source for microalgae cultivation. By leveraging its mineral content and cost-effectiveness, this research investigates the potential to reduce production expenses associated with nutrient mediums, thus enhancing the value proposition of microalgae-derived products on a commercial scale. In order to assess its efficacy, cow urine was gathered, diluted, and introduced into our Spirulina-modified medium. This concoction was subjected to 8 hours of daily light exposure. Following an 18-day incubation period, we analysed the biomass quantity, specific growth rate, density, chlorophyll level, and total carotenoid content. In the Aquatic Biology laboratory at VNSGU, an experiment was conducted utilizing five distinct concentrations (0.2 ml, 1 ml, 2 ml, 3 ml, and 4 ml in 200 ml) over an 18-day period. The control flask (0 ml) did not contain cow urine. In our current investigation, Spirulina cultivated in a cow urine extract at a concentration of 0.2 ml/200 ml exhibited a dry weight of 0.034±0.0029 g, a specific growth rate of 0.0016±0.00015, and a carotenoid content of 4.683±0.015. The density of Spirulina peaked at 0.0052±0.00005 with a concentration of 1 ml/200 ml of cow urine extract. Across various concentrations of cow urine extract, including 2 ml/200 ml (8.022±0.016 mg/L), 0.2 ml/200 ml (2.191±0.021 mg/L), and 4 ml/200 ml (0.631±0.020 mg/L), Spirulina exhibited higher levels of chlorophyll a, b, and c compared to the control medium in indoor culture setups.

Study on isolating, breeding, and cultivation of Xylaria nigripes (Klotzsch) Cooke

The Xylaria nigripes fungus is one of the medicinal materials that was used in traditional medicine. Extracts from the mycelium and fruiting bodies of the X. nigripes showed protecting cells, preventing DNA damage, and reducing the programmed death cell rate. In this study, the fruiting bodies of the X. nigripes were collected to isolate, propagate in the liquid medium, and then cultured to induce the fruiting body formation in the rice medium. The results showed that the X. nigripes was successfully isolated on PDAY (Potato Dextrose Agar Yeast Extract) medium, and the mycelium and spore of the X. nigripes had unique characteristics of the species. The biomass of X. nigripes grew well in a liquid nutrient medium containing 20g glucose, 1g MgSO4.7H2O, 2g KH2PO4, and 5g peptone, reaching the best mass after 21 to 28 days. Using an initial cultured liquid of X. nigripes to culture on rice medium, fruiting bodies were formed and developed after 14 days of culture. This result could potentially be applied to the production of X. nigripes biomass via mycelium and fruit bodies for application in medicine.

In vitro and in vivo screening of bacterial species from contaminated soil for heavy metal biotransformation activity

Heavy metals (HMs) are widely used in various industries. High concentrations of HMs can be severely toxic to plants, animals and humans. Microorganism-based bioremediation has shown significant potential in degrading and detoxifying specific HM contaminants. In this study, we cultivated a range of bacterial strains in liquid and solid nutrient medium containing different concentrations of different HMs to select and analyze bacteria capable of transforming HMs. The bacterial strains most resistant to selected HMs and exhibiting the ability to remove HMs from contaminated soils were identified. Then, the bacterial species capable of utilizing HMs in soil model experiments were selected, and their ability to transform HMs was evaluated. This study has also generated preliminary findings on the use of plants for further removal of HMs from soil after microbial bioremediation. Alcaligenes faecalis, Delftia tsuruhatensis and Stenotrophomonas sp. were selected for their ability to grow in and utilize HM ions at the maximum permissible concentration (MPC) and two times the MPC. Lysinibacillus fusiformis (local microflora) can be used as a universal biotransformation tool for many HM ions. Brevibacillus parabrevis has potential for the removal of lead ions, and Brevibacillus reuszeri and Bacillus safensis have potential for the removal of arsenic ions from the environment. The bacterial species have been selected for bioremediation to remove heavy metal ions from the environment.

Morphological, physiological, molecular, and pathogenic insights into the characterization of Phytophthora polonica from a novel host, hazelnut (Corylus avellana)

Hazelnuts, constituting a significant global crop, hold paramount importance in Türkiye, contributing to approximately 71.14 % of the world's hazelnut cultivation area. In the summer of 2023, hazelnut trees in two orchards situated in the Altınordu district of Ordu province, within the Black Sea region of Türkiye, the largest producer and exporter of hazelnuts, exhibited symptoms of decline associated with root rot. Phytophthora sp. was consistently isolated from necrotic taproots, initiating an in-depth study to discern the causal agent behind the observed hazelnut decline. The species was identified as P. polonica by its distinctive morphological traits, including homothallic characteristics, amphigynous or paragynous antheridia, long nonbranching sporangiophores, and nonpapillate sporangia with internal proliferation. Multiple genetic markers (ITS, tub2, and COI) facilitated a clear differentiation of P. polonica from other Phytophthora species within Clade 9, supporting its classification within Subclade 9b. This investigation also evaluated the impact of diverse nutrient media (CA, V8A, and CMA), temperatures, and pH levels on the mycelial growth of P. polonica HPp-1 and HPp-2 isolates. The optimal conditions for maximal mycelial growth were determined through the D-optimal design of the Response Surface Method, revealing the significant influence of all factors on mycelial growth. The identified optimal conditions were at 26.09 °C, pH 5.12, with CMA as the nutrient medium. Validation experiments conducted under these optimal conditions unveiled mycelial growth of 7.24 ± 0.15 mm day−1 and 6.81 ± 0.09 mm day−1 for P. polonica HPp-1 and HPp-2 isolates, respectively, with an error of less than 5 %. Pathogenicity assessments confirmed P. polonica's virulence on hazelnuts, with distinct lesion development observed in twig inoculation, cut stem segments, and foliar tests. While no statistically significant difference was noted in lesion areas between HPp-1 and HPp-2 isolates in twig and stem segment assays, a statistical difference in leaf lesion areas (19.96 ± 2.04 cm2 and 9.16 ± 3.43 cm2) emerged in foliar tests after only a 5-day incubation period, indicating their high susceptibility to the pathogen. This study is the first to report P. polonica as a hazelnut pathogen in Türkiye and around the world, highlighting the previously non-existent threat of Phytophthora root rot in hazelnuts, given the substantial lack of scientifically documented cases related to hazelnut root rot diseases. The quadratic model design employed in physiological analyses is reliable for optimizing mycelial growth and can serve as a guiding framework for similar investigations.

Towards a standardised orchid germination protocol: determining the optimal duration of chemical scarification for orchid seeds by means of viability and permeability staining

Complex nutrient media are used for the germination of orchids in the laboratory. These substrates are also suitable for the growth of microbes and thus the sterilization of both the medium and the seeds prior to sowing is mandatory. The surface disinfection of orchid seeds with chemical substances eliminates possible infections and enhances germination in several cases, by chemically scarifying their seed coats. However, long durations of chemical treatments may result in viability loss, and consequently, precisely determining the optimal treatment duration is essential for developing effective germination protocols. In this study, the double staining technique with Tetrazolium Chloride and Trypan Blue is tested as a proxy method to determine the optimal chemical treatment duration for 10 orchid taxa of Greece. Various durations of chemical treatment with 5% Ca(OCl)2 were carried out on independent seed samples which were subsequently tested, pairwise, for both germination and viability. The results in the corresponding experiments are extraordinarily similar and we conclude that the double viability staining is a quick and accurate technique in determining the permeability and optimal duration for chemical scarification prior to germination experiments. The storability potential of the taxa studied is discussed in comparison with previous data of the NKUA Seed Bank.

The Capacity of Wharton's Jelly to Prolong the Survival of Skin Tissues ex vivo

Developing models for preclinical examinations to avoid using animals has been increasing worldwide. Besides creating cell lines or tissues specialized for in vitro testing, biological wastes are also utilized as a potential tissue source for ex vivo examinations. In particular, the human skin from plastic surgery can be an ideal source of skin models to evaluate the effectiveness of some biological products with the advantage of possessing a natural finished skin structure. However, to maintain skin viability under laboratory conditions, it is necessary to establish ex vivo skin tissue nurturing conditions. Therefore, we tested conditions for culturing skin tissue outside the body using the air-liquid interface tissue culture method and Wharton's Jelly (WJ) from the umbilical cords and nutrient medium. The results showed that the skin tissue could maintain and survive in the air-liquid interface tissue culture conditions. Results from observations showed that the size and color of skin tissues were consistent until ten days and 15 days, when skin tissues were maintained in the nutrient media or nutrient media combined with WJ, respectively. Additionally, the histological analysis indicated that cultured skin tissues could maintain their normal structure of three epidermis, dermis, and hypodermis layers; the epidermis started to separate from the dermis after ten days or 15 days, depending on whether skin tissues were maintained in nutrient media only or nutrient media combined with WJ, respectively. Moreover, hair follicles, melanocytes, and keratinocytes were observed at their right location and typical structure. These results indicated that skin could survive in a nutrient medium for ten days, particularly prolonged over 15 days in a combination of nutrient medium and WJ. These results indicated the potential to maintain skin tissue ex vivo and use it for different tests under laboratory conditions.

Delineating the role of host plants in regulating the water and salinity stress induced changes in sandalwood roots.

The interaction of root hemi-parasite (sandalwood) with its hosts is crucial for establishing successful plantations under abiotic stresses. In the present study, we explored the best possible host for sandalwood along with its effect on sandalwood physiology in terms of water and nutrients. Interactive effects of host species (Alternanthera sp., Azadirachta indica, Dalbergia sissoo, Melia dubia, and Aquilaria malaccensis) with sandalwood were observed under eight treatments {100% best available water (BAW); 100% BAW + nutrient medium; 50% water deficit; 50% water deficit + nutrient medium; 100% saline water (ECiw 8ds/m); 100% saline water (ECiw 8ds/m) + nutrient medium; 50% water deficit + saline water (ECiw 8ds/m); and 50% water deficit + saline water (ECiw 8ds/m) + nutrient medium}. A significant change in morpho-physiological traits of sandalwood roots was observed under different stress conditions, which were slightly improved through external supply of nutrient medium. Dalbergia sissoo (Shisham) and Melia dubia (Dek) seemed to be the best host plants providing better environment for sandalwood growth and development, i.e., higher plant height (59.7 and 53.68cm) and collar diameter (3.24 and 3.07mm) under stresses by maintaining water and ionic balance. Root length is an important parameter that was reduced by 27.58%, 19.22%, and 36.3% under water deficit, salinity, and combined stress of water deficit and salinity. Sandalwood grown with D. sissoo and M. dubia maintained the lowest Ψw (-1.38MPa) and Ψs (-1.47 and -1.48MPa), respectively. In addition, sandalwood cultivated with D. sissoo and A. indica had higher accumulation of soluble proteins (0.48 and 0.42mg/g) and soluble sugars (98.56 and 91.04mg/g) in their roots. Results also showed that sandalwood roots had higher K+/Na+ with compatible host, i.e., with A. indica (1.85) and D. sissoo (1.83) than other studied hosts. It was also observed that sandalwood plants could not grow and survive alone under stress conditions even with application of nutrient medium. Based on the morphological traits, it was observed that sandalwood grown with hosts, Dalbergia sissoo and Melia dubia, was able to tolerate stress conditions better than other studied hosts. We can further recommend growing sandalwood with D. sissoo and M. dubia as a viable option to endure adverse environmental conditions.

INFLUENCE OF DINITROSALICYLIC ACID ON THE PROTECTIVE SYSTEM OF COTTON SEEDLINGS (Gossypium hirsutum L.)

Cotton growing, being an important agro-industrial object, is being improved through the introduction of new mechanisms to increase resistance to various external stress factors. Taking into account the previously studied phytohormones, the purpose of our study was to identify the effect of the salicylic acid derivative, dinitrosalicylic acid (DNSA), on the biochemical processes in the common cotton AP-317 genotype. It was established that low concentrations of DNSA-0.01 mM decreased production of NO radical, catalase and PPO activity, as well as absorption of phosphorus-anions from the nutrient medium, while higher doses of them has led to the stimulation of NO radical production, increased peroxidase activity, stabilized absorption of phosphorus anions. It was also found that at low concentrations of DNSA took place slightly activation of SOD activity, but not at relatively high concentration of DNSA. Electron paramagnetic resonance analysis of the root and leaf tissue of the plant showed an increase in the concentration of magnesium and iron ions when exposed to DNSA. It was also found that DNSA increased the concentration of lipid peroxide radicals at 0.1 mM in both tissues.

Introduction of Salicornia europaea L into in vitro culture

The goal of the research was to develop a technology for introducing Salicornia europaea L.into in vitro culture. Methods of cultivating meristems and callus cultures were studied. To cultivate meristems, the tip of the apical bud were used as an explant. Fragments of stems and leaves were used toobtain callus tissue. To study the influence of various factors on germination, seeds were soaked in sterile tap water and in solutions of gibberellin, cytokinin, auxin and NaCl, and were also subjected to cold stratification (independently and with subsequent placement in Knop’s agarized medium). Salicornia seeds were sterilized with various antiseptics: 70% alcohol, 10% aqueous solution of sodium hypochlorite («Belizna»), amoxicillinand 3% hydrogen peroxide. The ability of the culture to form callus was studied in MS medium. As a result, it was determined that the highest germination of seeds was observed in Knop medium after treating theseeds with a suspension of green algae of the Scenedesmus genus, as well as after preliminary cold stratification, and slightly less after treating the seeds with a solution of NaCl and gibberellic acid. The most effective method of seed sterilization turned out to be treatment with alcohol followed by treatment with sodium hypochlorite. A comparative analysis of seed germination in filter paper in Petri dishes, Knop agar medium, Murashige and Skoog (hormone-free) was carried out. The ability of S. europaea L. to form callusin MS medium with phytohormones was assessed. Conclusion. To improve germination, it is recommended to subject the seeds to cold stratification. To obtain aseptic explants quickly, it is recommended to germinate the seeds in the Knop nutrient medium, having previously sterilized them with alcohol, then with sodiumhypochlorite, followed by washing with distilled water. The most suitable type of microclonal propagationfor S. europaea L. is the production of callus tissue followed by induction of organogenesis or embryogenesis.

A two-phase thin-film model for cell-induced gel contraction incorporating osmotic effects

We present a mathematical model of an experiment in which cells are cultured within a gel, which in turn floats freely within a liquid nutrient medium. Traction forces exerted by the cells on the gel cause it to contract over time, giving a measure of the strength of these forces. Building upon our previous work (Reoch et al. in J Math Biol 84(5):31, 2022), we exploit the fact that the gels used frequently have a thin geometry to obtain a reduced model for the behaviour of a thin, two-dimensional cell-seeded gel. We find that steady-state solutions of the reduced model require the cell density and volume fraction of polymer in the gel to be spatially uniform, while the gel height may vary spatially. If we further assume that all three of these variables are initially spatially uniform, this continues for all time and the thin film model can be further reduced to solving a single, non-linear ODE for gel height as a function of time. The thin film model is further investigated for both spatially-uniform and varying initial conditions, using a combination of analytical techniques and numerical simulations. We show that a number of qualitatively different behaviours are possible, depending on the composition of the gel (i.e., the chemical potentials) and the strength of the cell traction forces. However, unlike in the earlier one-dimensional model, we do not observe cases where the gel oscillates between swelling and contraction. For the case of initially uniform cell and gel density, our model predicts that the relative change in the gels’ height and length are equal, which justifies an assumption previously used in the work of Stevenson et al. (Biophys J 99(1):19–28, 2010). Conversely, however, even for non-uniform initial conditions, we do not observe cases where the length of the gel changes whilst its height remains constant, which have been reported in another model of osmotic swelling by Trinschek et al. (AIMS Mater Sci 3(3):1138–1159, 2016; Phys Rev Lett 119:078003, 2017).

Silver nanoparticle-induced in vitro flowering in Dendrocalamus strictus (Roxb.) nees and genetic fidelity assessment of regenerants using molecular markers.

Dendrocalamus strictus (Roxb.) Nees, generally referred to as 'Male bamboo,' is a globally prevalent and highly significant species of bamboo. It is a versatile species and possesses notable industrial significance. However, despite its numerous applications, the production of this plant is insufficient to fulfill the worldwide demand. The challenges that impede the dissemination of D. strictus encompass the unpredictable blooming pattern (30-70 years), low seed production, and limited seed viability. Therefore, tissue culture presents a reliable and effective option for the mass production of standardized planting material. This study investigated the effects of silver nanoparticles (AgNPs) at a concentration of 6.0 mg L- 1 in the Murashige and Skoog (MS) nutrient medium fortified with pre-optimized plant growth regulators (3.0 mg L- 1 6-benzylaminopurine + 0.5 mg L- 1 α-naphthalene acetic acid) on the induction of flowering in a controlled environment in D. strictus. The use of AgNPs in the media induced a maximum of 14 inflorescences per culture vessel, 9 flowers per inflorescence, and improved the performance of the micropropagated plantlets during acclimatization in the greenhouse and field. The ISSR and SCoT amplified polymorphic DNA analysis of the regenerants resulted in the formation of 49 bands (300 to 2000bp size) and 36 scorable bands (350 to 2000bp) respectively. All the PCR amplicons produced by SCoT and ISSR were monomorphic confirming the genetic uniformity of the tissue cultured plants of D. strictus with the mother plant. It can be inferred that the incorporation of AgNPs during the shoot proliferation phase has the potential to stimulate in vitro flowering in D. strictus. This finding could provide valuable insights into innovative strategies for enhancing crop productivity and genetic manipulation for accelerated breeding and agricultural advancement.

Nutrients recovery from dairy wastewater by Chlorella vulgaris and comparison of the lipid's composition with various chlorella strains for biodiesel production.

Microalgae biomass is regarded as a promising feedstock for biodiesel production. The biomass lipid content and fatty acids composition are among the main selective criteria when screening microalgae strains for biodiesel production. In this study, three strains of Chlorella microalgae (C. kessleri, C. sorokiniana, C. vulgaris) were cultivated nutrient media with different nitrogen contents, and on a medium with the addition of dairy wastewater. Moreover, microalgae grown on dairy wastewater allowed the removal of azote and phosphorous. The removal efficiency of 90%, 53% and 95% of ammonium nitrogen, total nitrogen and phosphate ions, respectively, were reached. The efficiency of wastewater treatment from inorganic carbon was 55%, while the maximum growth of biomass was achieved. All four samples of microalgae had a similar fatty acid profile. Palmitic acid (C16:0) was the most abundant saturated fatty acid (SFA), and is suitable for the production of biodiesel. The main unsaturated fatty acids (UFA) present in the samples were oleic acid (C18:1 n9); linoleic acid (C18:2 n6) and alpha-linolenic acid (C18:3 n3), which belong to omega-9, omega-6, omega-3, respectively.