Nostoc Linckia Research Articles

Microalgae–bacteria interaction: a catalyst to improve maize (Zea mays L.) growth and soil fertility

AbstractBiofertilisers harbouring living organisms hold allure due to their prospective favourable influence on plant growth, coupled with a diminished environmental footprint and cost-effectiveness in contrast to conventional mineral fertilisers. The purpose of the present study was to evaluate the capacity of a specific microalga (MACC-612, Nostoc linckia) biomass and plant growth-promoting bacteria (PGPB) separately and together to improve crop growth and promote soil health. The research used a factorial design within a completely randomised block framework, featuring four replications for three consecutive years across different fields. The experiment utilised three levels of microalga (control, 0.3 g/L of N. linckia, MACC-612, and 1 g/L of N. linckia, MACC-612) and three levels of bacterial strains (control, Azospirillum lipoferum and Pseudomonas fluorescens). The result demonstrated that the use of N. linckia and PGPB separately or jointly as soil treatment resulted in a substantial improvement in chlorophyll, plant biomass, soil humus, and nitrogen, depending on the environmental conditions of the years. The combined use of N. linckia and PGPB results in an improvement in dry leaf weight by 35.6–107.3% at 50 days after sowing (DAS) and 29.6–49.8% at 65 DAS, compared to the control group. Furthermore, the studies show that the synergistic application of N. linckia at 0.3 g/L, in conjunction with A. lipoferum, significantly improved total nitrogen and (NO3− + NO2−)-nitrogen, registering increases of 20.7–40% and 27.1–59.2%, respectively, during the study period. The most effective synergistic combination was identified through the application of 0.3 g/L of N. linckia along with A. lipoferum. Hence, application of biofertilisers through synergistic combinations of two or more microorganisms, such as microalgae and bacteria, holds promise in improving crop chlorophyll, growth, and soil nitrogen.

PROSPECTS OF BIODIESEL PRODUCTION FROM NOSTOC LINCKIA (ROTH.) BORN. ET FLAH. BIOMASS

The work is devoted to the optimization of the process of obtaining purified lipids for the production of biodiesel from Nostoc linckia biomass. The cyanobacteria were cultivated in a photobioreactor on a medium of minimal mineral composition. The biomass was separated from the fugate and dried to a constant weight. Different systems of polar and nonpolar solvents were tested for lipid extraction. The solvent system petroleum ether : butanol (1 : 2) was the most effective in the extraction of N. linckia lipids. The presence of phospholipids, free fatty acids, acidic substances, and waxes in the extract was checked. Depending on their presence, the mandatory stages of lipid refining were established. N. linckia biomass is a promising raw material for biodiesel production. The optimized methodology allows us to obtain purified lipids in the amount of 19.4% of the dry weight of the feedstock. Keywords: Nostoc linckia (Bornet ex Bornet et Flahault, 1886), biodiesel, lipids, extraction, refining, microalgae

EFFECTS OF NITROGEN NUTRIENT ON THE PRODUCTION OF MYCOSPORINE-LIKE AMINO ACIDS IN NOSTOC SPECIES

Mycosporine-like amino acids MAAs belong to a family of secondary metabolites produced by a wide range of different organisms. These compounds had several potential applications in biomedical, in cosmetics and toiletries. In the present study, three Nostoc strains distributed in soil and freshwater were tested for MAA production under different nitrogen conditions. UV-B radiation significantly enhanced the production of MAAs in Nostoc linckia, Nostoc muscorum and Nostoc paludosum under nitrogen sufficient and deficient conditions. The contents of MAAs significantly increased in these three Nostoc strains with prolonged UV-B treatment under both nitrogen conditions. Both UV-B exposed N. muscorum and N. paludosum produced much less MAAs under nitrogen deficiency in comparison to culture under nitrogen sufficiency, respectively. There was just little difference of MAA contents in UV-B treated N. linckia when it was cultured under both nitrogen conditions. After separation by HPLC and characterization by in-line absorption spectra and mass spectra, one type of MAA porphyra was induced by UV-B in N. linckia under nitrogen sufficient and deficient conditions, and N. muscorum synthesized another kind of MAA shinorine under nitrogen sufficient and deficient conditions. However, UV-B induced N. paludosum to produce porphyra under nitrogen sufficient condition but shinorine under nitrogen deficient condition. These results indicated the nutrient nitrogen levels could regulate the types and amounts of MAAs in Nostoc species. These strains would be a better source for the industrial production of MAAs that can be used as organisms for studying the biosynthetic route of MAAs in nitrogen conditions.

New Nostocyclophanes from Nostoc linckia.

Six new nostocyclophanes and four known compounds have been isolated from Nostoc linckia (Nostocaceae) cyanobacterial strain UTEX B1932. The new compounds, nostocyclophanes E-J (1-6), were characterized by NMR and MS techniques. The known compounds were nostocyclophanes B-D, previously isolated from this strain, and dedichloronostocyclophane D. Structural modifications on the new [7.7]paracyclophane analogs 1-5, isolated from the 80% methanol fraction, range from simple changes such as the lack of methylation or halogenation to more unusual modifications such as those seen in nostocyclophane H (4), in which the exocyclic alkyl chains are of different length; this is the first time this modification has been observed in this family of natural products. In addition, nostocyclophane J (6) is a linear analog in which C-20 is chlorinated in preparation for the presumed enzymatic Friedel-Craft cyclization needed to form the final ring structure, analogous to the biosynthesis of the related cylindrocyclophanes. Nostocyclophane D, dedichloronostocyclophane D, and nostocyclophanes E-J demonstrated moderate to weak growth inhibition against MDA-MB-231 breast cancer cells.

Growth and photosynthetic performance of Nostoc linckia (formerly N. calcicola) cells grown in BG11 and BG110 media

The biotechnological potential of Nostoc linckia as a biofertilizer and source of bioactive compounds makes it important to study its growth physiology and productivity. Since nitrogen is a fundamental component of N. linckia biomass, we compared the growth and biochemical composition of cultures grown in BG11 (i.e., in the presence of nitrate) and BG110 (in the absence of nitrate). Cultures grown in BG11 accumulated more cell biomass reaching a dry weight of 1.65 ± 0.06 g L–1, compared to 0.92 ± 0.01 g L–1 in BG110 after 240 h of culture. Biomass productivity was higher in culture grown in BG11 medium (average 317 ± 38 mg L–1 day–1) compared to that attained in BG110 (average 262 ± 37 mg L–1 day–1). The chlorophyll content of cells grown in BG11 increased continuously up to (39.0 ± 1.3 mg L–1), while in BG110 it increased much more slowly (13.6 ± 0.8 mg L–1). Biomass grown in BG11 had higher protein and phycobilin contents. However, despite the differences in biochemical composition and pigment concentration, between BG11 and BG110 cultures, both their net photosynthetic rates and maximum quantum yields of the photosystem II resulted in similar.Graphical

Systemic resistance induction of tomato plants against tomato mosaic virus by microalgae

BackgroundTomato mosaic virus (ToMV) is a dangerous disease of tomato (Lycopersicon esculentum) that reduces dramatically the yield. To reduce ToMV infection, microalgal isolates were utilized. Microalgal species (Chlorella vulgaris, Anabaena oryzae, Spirulina platensis, Nostoc linckia and Dunaliella salina) were shown to be responsible for the stimulation of tomato resistance against ToMV.ResultsInitial signs of discoloration and mosaic in ToMV-inoculated plants were detected and identified on inoculated leaves at 6 and 12 dpi in control and treated plants, respectively, suggesting that microalgae may inhibit ToMV growth. Treatment with microalgae resulted in a significant decrease in symptoms (up to 63% reduction in disease severity) and negative ELISA readings, indicating that the microalgae induced resistance in tomato against ToMV infection. The isolates also enhanced the activity of pathogenesis-related enzymes (PPO and POX reaching to 0.033 and 0.054 in D. salina, respectively), as well as tomato growth characters in comparison with the control. Microalgal treatments demonstrated that the salicylic acid (SA) and jasmonic acid (JA) pathways were involved in tomato plant defense responses. The relative gene expressions of PR1 and phenylalanine ammonia lyase (PAL), which are involved in the SA and JA pathways, respectively, were improved in treated plants compared to the control.ConclusionThe findings indicated that algal-induced ToMV resistance was mediated via several defense pathways in tomato. The antiviral mechanism was described, which provides a light on the potential of algae in plant viral disease management.

Peculiarities of the Edaphic Cyanobacterium Nostoc linckia Culture Response and Heavy Metal Accumulation from Copper-Containing Multimetal Systems.

Soil and water pollution is a major problem that has a negative impact on ecosystems and human health in particular. In the bioremediation processes, the application of photosynthetic microorganisms, including cyanobacteria, is a direction of action addressed with increasing frequency in the context of further development and improvement of environmentally friendly techniques needed for detoxification of soils and waters polluted with low concentrations of toxic elements, since they pose a challenge for traditional treatment methods. In the present study, the removal of copper and other metal ions from multielement systems by three generations of Nostoc linckia is discussed. Changes in the biochemical composition of the nostoc biomass, which accumulates metal ions, were monitored. Neutron activation analysis was applied to assess Cu, Fe, Ni, and Zn accumulation by biomass, as well as to determine the biochemical composition of biomass after specific biochemical methods were used. The capacity of the accumulation of copper and other metal ions from multi-elemental systems by cyanobacteria Nostoc linckia was high and increased over two cycles of biomass growth in the systems Cu-Fe-Ni and Cu-Fe-Zn and over three cycles in Cu-Fe and Cu-Fe-Ni-Zn systems. It constituted 1720–10,600 µg metal/g depending on the system and cycle of cultivation. The accumulation of Fe, Ni, and Zn also increased over the generations of nostoc. The process of metal accumulation was demonstrated by a significant change in the biomass biochemical composition. Cyanobacteria Nostoc linckia possess a pronounced capacity of copper and other metal ion accumulation from multimetal systems and showed an increased resistance in environments polluted with heavy metals.

Biological control of Fusarium tomato-wilt disease by cyanobacteria Nostoc spp.

This study investigated the effect of foliar application of extract and culture of Nostoc calcicola and Nostoc linckia on the Fusarium oxysporum f. sp. lycopersici (FOL) that infects tomatoes (Solanum lycopersicum) plant in vitro and in vivo. Cyanobacterial isolates were isolated from saline soils at El-Hamoul and Seidy Salem locations Kafr Elsheikh, Egypt, and identified to be N. calcicola and N. linckia Bioactive compounds of extract were analyzed by Gas chromatography-mass spectrometry (GC-MS). Dry weight, carotene, chlorophyll content, and total phenolic compounds of isolates were measured. Plant height, dry weight, fruit number, and fruit weight of tomatoes were estimated. GC/MS analysis showed 49 and 35 bioactive compounds in extracts of N. calcicola and N. linckia, respectively. N. calcicola possesses the highest values of chlorophyll a, carotenoid, and total phenol contents in dry weight compared with N. linckia. After 100days of tomato growth, the results showed the highest yield of tomato fruits with the application of N. calcicola and N. linckia compared with the untreated plants and the plants which were infected with Fusarium, suggesting that N. calcicola and N. linckia can serve as a new bioagent for biological control of the soil fungus Fusarium oxysporum f. sp. lycopersici (FOL).

Bioremediation Capacity of Edaphic Cyanobacteria Nostoc linckia for Chromium in Association with Other Heavy-Metals-Contaminated Soils

Anthropogenic activity is the main factor contributing to soil pollution with various toxic metals, including Cr(VI), which dictates the need for decontamination. Often, the traditionally used remediation methods (soil removal, stabilization/solidification, physicochemical extraction, and soil washing) are not sufficiently efficient. Among gentle soil remediation, options can be considered. The aim of this study is to assess the ability of Nostoc linckia to remediate soils contaminated with Cr(VI) in association with other metals. Metal uptake by biomass was assessed using neutron activation analysis, while the components of Nostoc biomass were determined using specific methods. The capacity to accumulate chromium from the contaminated environment (Cr in association with Fe, Ni, Cu, and Zn) by the Nostoc linckia is kept at a high level for three generations of cyanobacterium, and the capacity to accumulate Fe, Ni, Cu, and Zn is growing over the cultivation cycles. The process of accumulation of heavy metals is associated with significant changes in the biochemical composition of Nostoc biomass. Due to the high bioaccumulation capacity and the specific growth mode with the formation of crusts on the soil surface, the edaphic cyanobacteria Nostoc linckia is an important candidate for the bioremediation of soil contaminated with chromium in association with other metals.

Potential Antioxidant and Anticancer Activities of Secondary Metabolites of Nostoc linckia Cultivated under Zn and Cu Stress Conditions

The objective of the present study is to determine the antioxidant and anticancer activities of Nostoc linckia extracts cultivated under heavy metal stress conditions (0.44, 0.88, and 1.76 mg/L for zinc and 0.158, 0.316, 0.632 mg/L for copper). Phycobiliprotein, phenolic compounds, flavonoids, and tannins were measured. Active ingredients of extracts were evaluated by GC-mass spectroscopy. The obtained results revealed that higher zinc and copper concentrations showed growth inhibition while 0.22 mg/L (Zn) and 0.079 mg/L (Cu) enhanced growth, reaching its maximum on the 25th day. Increases in catalase, lipids peroxidation, and antioxidants, as well as tannins and flavonoids, have been induced by integration of 0.88 mg/L (Zn) and 0.316 mg/L (Cu). Elevation of Zn concentration induced augmentation of antioxidant activity of crude extract (DPPH or ABTS), with superior activity at 0.44 mg/L zinc concentration (81.22%). The anticancer activity of Nostoc linckia extract (0.44 mg/L Zn) tested against four cancer cell lines: A549, Hela, HCT 116, and MCF-7. The extract at 500 µg/mL appeared the lowest cell viability of tested cell lines. The promising extract (0.44 mg/L Zn) recorded the lowest cell viability of 25.57% in cervical cell line, 29.74% in breast cell line, 33.10% in lung cell line and 34.53% in the colon cell line. The antioxidant active extract showed significant stability against pH with attributed increase in antioxidant activity in the range between 8–12. The extract can be used effectively as a natural antioxidant and anticancer after progressive testing.

Biosynthesis and Heterologous Production of Mycosporine-Like Amino Acid Palythines.

Mycosporine-like amino acids (MAAs) are a family of natural products that are produced by a variety of organisms for protection from ultraviolet damage. In this work, we combined different bioinformatic approaches to assess the distribution of the MAA biosynthesis and identified a putative gene cluster from Nostoc linckia NIES-25 that encodes a short-chain dehydrogenase/reductase and a nonheme iron(II)- and 2-oxoglutarate-dependent oxygenase (MysH) as potential new biosynthetic enzymes. Heterologous expression of refactored gene clusters in E. coli produced two known biosynthetic intermediates, 4-deoxygadusol and mycosporine-glycine, and three disubstituted MAA analogues, porphyra-334, shinorine, and mycosporine-glycine-alanine. Importantly, the disubstituted MAAs were converted into palythines by MysH. Furthermore, biochemical characterization revealed the substrate preference of recombinant MysD, a d-Ala-d-Ala ligase-like enzyme for the formation of disubstituted MAAs. Our study advances the biosynthetic understanding of an important family of natural UV photoprotectants and opens new opportunities to the development of next-generation sunscreens.

Enhancement of active ingredients and biological activities of Nostoc linckia biomass cultivated under modified BG-110 medium composition.

The current work aims to investigate the effect of abiotic stresses (nitrogen (N) and sulfur (S) [0.0 g/l, 1.5 g/l, 3 g/l, 6 g/l, and 12 g/l N and 0.0 g/l, 0.07 g/l, 0.15 g/l, 0.3 g/l, and 0.6 g/l S] and their combination [0.3 g/l S + 6 g/l N]) of axenic culture of Nostoc linckia on the production of secondary metabolites which induce different biological activities. Growth rate was measured by dry weight (DW) and optical density (OD)550 nm. Additionally, phytochemical compounds, defense enzymes as well as antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(ethylbenzthiazoline-6-sulfonic acid) (ABTS·+) radical assays of crude extracts (methylene chloride:methanol, 1:1) were evaluated. Based on antioxidant activity, four promising extracts were subjected to different biological activities such as anticancer, antimicrobial, and antiviral activities. The obtained results revealed that supplementation of external nitrogen source in the form of sodium nitrate was found to increase the total phycobiliprotein content by fivefold. Also, nitrogen depletion provoked significantly highest quantities of phenolic and flavonoid content and this has effects on biological activities of Nostoc linckia. Moreover, 0.3 g/l S was found to be the most effective extract exhibiting a significant increase in antioxidant activity based on DPPH and ABTS assays, respectively (88.18 ± 0.64% and 84.20 ± 1.01%). Furthermore, it recorded anticancer activity against HCT 116 cell line with IC50 of 155 μg/ml. Moreover, this extract possessed a noticeable antibacterial potency (21.0 ± 1.0 as mm inhibition zone against Staphylococcus aureus and 19.3 ± 0.6 against Streptococcus mutans). In addition, its antiviral activity against H5N1 virus as a percentage of inhibition was 50% and 63.6% at a concentration of 7 μg/ml and 28 μg/ml, respectively, with cytotoxicity less than 7 μg/μl. GC-MS analysis recorded the presence of bioactive compounds exhibiting different biological activities. Therefore, the obtained results can represent valuable bioactive compounds with variable biological potencies.

Biosynthesis of metal nanoparticles using blue-green algae (Cyanobacteria) and their possible applications: Thesis Abstract

Thesis Abstract Background: Silver nanoparticles has attracted much attention as its appropriate solvent systems and ecological reducing agents so, its synthesis was of wide prominence and were functional in many fields. Aim: The present work was designed for the biosynthesis of AgNPs by seven cyanobacterial species using their filtrate and biomass separately and also their crude phycobiliproteins extract of Nostoc linckia and Spirulina platensis which scored the highest quantities. Results: Appearance of surface plasmon band at 400 nm for filtrate and biomass while at 420 nm crude phycobiliproteins extract that indicated the biosynthesis of AgNPs. FTIR analysis suggested that proteins were responsible for their capping and stabilization. XRD analysis confirmed its spherical crystalline shape. Zeta potential recorded -15.9 mV and -16.8 mV for S. platensis and N. linckia AgNPs, respectively confirming its stability. TEM images revealed that AgNPs had a mean average size of 21.2 and 21.05 nm for S. platensis and N. linckia, respectively. AgNPs showed potent antimicrobial activity against Gram positive, Gram negative bacteria and Candida albicans using the disk diffusion method. The antioxidant activity of AgNPs was promising by using three assays of DPPH radical scavenging activity, total antioxidant capacity and ferric reducing antioxidant power. The cytotoxicity of AgNPs was tested on HepG2 cell line through neutral red assay and the NPs of both species proved to be safe in low concentrations. Significant antiviral activity against HCV (64.976%) was recorded for AgNPs of N. linckia which was comparable to Ribavirin (66.67%) as a standard drug while S. platensis AgNPs recorded 48.3%. Conclusion: Biosynthesis of metal nanoparticles using blue-green algae (Cyanobacteria) can express potenial anti-cancer activities.

The participation of cyanobacteria in reducing the concentration of fusariotoxins and heavy metal ions in aqueous solutions (model experiments)

Aim. The goal was to establish the effect of soil cyanobacteria (CB) Fischerella muscicola, Nostoc paludosum and Nostoc linckia on change in the concentration of heavy metal ions (HM) and fusariotoxins in aqueous media.Material and Methods. In order to plot the kinetics of sorption by dry biomass of CB Fischerella muscicola and Nostoc paludosum of copper(II), lead(II) and cadmium ions from solutions with a concentration of 10‐4mol/L, the method of potentiometry with ion‐selective electrodes was used. The concentration of fusariotoxins in the filtrate of the contact medium of Fischerella muscicola CB and Nostoc linckia with F. culmorumwas determined by HPLC.Results. The kinetics of sorption of TM ions by dry biomass of the CB isbest described by a modified second‐order model. According to the model, the sorption process limits the ion exchange reaction. In the presence of CB Fischerella muscicola and Nostoc linckia with a titer of 1.8∙106 cells/mL (1:100 dilution), a decrease in toxin and lycomarasmin in T‐2 medium occurs. However, this increases the concentration of fusaric acid and deoxynivalenol. In the variant where the titer of CB is equal to 1.8∙107cells/mL, the concentration of lycomarasmin is significantly reduced, while there is no change in the concentration of other fusariotoxins.Conclusion. Dry biomass of CB, having a high bisorption potential, can act as a good biosorbent with respect to copper(II), lead(II) and cadmium ions. A decrease in the concentration of fusariotoxins indicates the possibility of isolating active CB substances that can inhibit the biosynthesis of certain toxins of micromycetes of the genus Fusarium, reducing both the phytotoxicity of plant growth media and increasing the safety of crop production.

Comparative genomic insights into culturable symbiotic cyanobacteria from the water fern Azolla.

Species of the floating, freshwater fern Azolla form a well-characterized symbiotic association with the non-culturable cyanobacterium Nostoc azollae, which fixes nitrogen for the plant. However, several cyanobacterial strains have over the years been isolated and cultured from Azolla from all over the world. The genomes of 10 of these strains were sequenced and compared with each other, with other symbiotic cyanobacterial strains, and with similar strains that were not isolated from a symbiotic association. The 10 strains fell into three distinct groups: six strains were nearly identical to the non-symbiotic strain, Nostoc (Anabaena) variabilis ATCC 29413; three were similar to the symbiotic strain, Nostoc punctiforme, and one, Nostoc sp. 2RC, was most similar to non-symbiotic strains of Nostoc linckia. However, Nostoc sp. 2RC was unusual because it has three sets of nitrogenase genes; it has complete gene clusters for two distinct Mo-nitrogenases and an alternative V-nitrogenase. Genes for Mo-nitrogenase, sugar transport, chemotaxis and pili characterized all the symbiotic strains. Several of the strains infected the liverwort Blasia, including N. variabilis ATCC 29413, which did not originate from Azolla but rather from a sewage pond. However, only Nostoc sp. 2RC, which produced highly motile hormogonia, was capable of high-frequency infection of Blasia. Thus, some of these strains, which grow readily in the laboratory, may be useful in establishing novel symbiotic associations with other plants.

Antimicrobial, Antioxidant, and Antiviral Activities of Biosynthesized Silver Nanoparticles by Phycobiliprotein Crude Extract of the Cyanobacteria Spirulina platensis and Nostoc linckia

The present work was designed for the biosynthesis of silver nanoparticles (AgNPs) by Spirulina platensis and Nostoc linckia phycobiliprotein extract and for evaluation of their antimicrobial, antioxidant, and antiviral activities. The biosynthesized AgNPs were characterized by UV-Vis spectroscopy, Fourier transform-infrared spectroscopy, transmission electron microscopy, X-ray diffraction analysis, and Zeta potential analysis. The antimicrobial activity of the biosynthesized AgNPs was tested by the disk diffusion method. The antioxidant activity of the nanoparticles was assessed by using DPPH radical scavenging, total antioxidant capacity, and ferric reducing antioxidant assays. The antiviral activity of AgNPs was also challenged with the hepatitis C virus (HCV). The appearance of the surface plasmon resonance band at 420 nm indicated the biosynthesis of AgNPs. TEM images revealed that AgNPs had a mean average size of 21.211 and 21.052 nm for S. platensis and N. linckia, respectively. XRD analysis confirmed its spherical crystalline shape, and FTIR analysis suggested that proteins were responsible for their capping and stabilization. Zeta potential recorded − 15.902 mV and − 16.811 mV for S. platensis and N. linckia AgNPs, respectively, confirming its stability. AgNPs showed potent antimicrobial activity against some bacterial pathogens and Candida albicans. The antioxidant activity of AgNPs was evident by the use of three antioxidant assays. Significant antiviral activity against HCV (64.976%) was recorded for AgNPs of N. linckia, compared with Ribavirin (66.673%) as a standard drug, while S. platensis AgNPs recorded 48.334%. In conclusion, AgNPs biosynthesized from cyanobacterial phycobiliproteins were stable and showed potent antimicrobial, antioxidant, and antiviral activities.

Green synthesis of silver nanoparticles from some cyanobacterial species

Seven selected cyanobacterial species namely Nostoc linckia, Nostocmuscorum, Oscillatoria acuminata, Anabaena variables, Oscillatoriaamphigranulata, Spirulina platensis and Phormidium purpurascenswere cultivated on suitable media. In this work, the growth rates of weremeasured by optical density and dry weight, day after day. Spirulinaplatensis biomass was harvested at the 16th day which about equaled8.322 g/L dry biomass. Also the biomass of other selectedcyanobacterial species was collected at the 22nd day. The present workwas designed for the biosynthesis of AgNPs by seven cyanobacterialspecies using their filtrate and biomass separately. Appearance ofsurface plasmon band at 400 nm for filtrate and biomass indicated thebiosynthesis of AgNPs. UV-vis spectroscopy used to characterizebiosynthezied AgNPs and resulted in appearance of surface plasmonband at 400 nm for filtrate and biomass

Obtaining phycobiliprotein-containing Nostoc linckia (Roth.) Born. et Flah biomass via bioconversation of waste water from reticulating aquaculture systems (RAS)

The paper studies the possibility of bioconversion of waste water from recirculating aquaculture systems (RAS). For this purpose, cyanobacteria Nostoc linckia (Roth.) Born. et Flah. was grown on waste water from RAS. In the process of cultivation, indicators of total mineralization, pH, and culture density were monitored. In the waste water, the content of various forms of nitrogen (NH4+, NO3-, NO2-), the content of P and S before and after the growth of cyanobacteria were determined It was noted that as a result of growing N. linckia in RAS waste water, a decrease in the content of various forms of nitrogen, sulfur and phosphorus is observed. Also, the content of phosphates decreased from 35×10-3 to 5×10-3 mg.L-1 and the content of sulfates from 95×10-3 to 25×10-3 mg.L-1. Moreover, the resulting biomass of cyanobacteria contained 57 % of proteins, 20 % of lipids and 11% of carbohydrates. It was found that N. linckia biomass is a promising source of phycobiliprotein pigments: phycocyanin, allophycocyanin and phycoerythrin.

Nostoc linckia (Bornet ex Bornet et Flahault, 1886) (Nostocales: Cyanobacteria) from the Sea of Azov: Morphology and Molecular Investigation of Toxigenicity

The Sea of Azov is a part of the Mediterranean basin and is the most continental sea in the world. But the phycological studies of the Sea of Azov were irregular. To assess the ecological safety of sea water, it is important not only to determine the presence of toxigenic species in the flora, but also to confirm the presence of strains capable of synthesizing toxins. The strain Nostoc linckia MZ–C21 was isolated from a planktonic sample collected near a seacoast of the Sivash (the bay of the Sea of Azov near Henichesk, Ukraine). PCR reactions demonstrated that the investigated strain has genes encoding all known groups of hepatotoxins: microcystin (the mcyE gene), nodularin (the ndaF gene), and cylindrospermopsin (the cyrB gene) synthetases. The novel strain MZ–C21 formed strongly supported phylogenetic lineages with other microcystin and nodularin producers. Thus, there is a high probability for the production of cyanotoxins by Nostoc linckia growths in the Sea of Azov near Henichesk.

Phototrophic microorganisms for agricultural technology and food security

The main idea of the study was to find cyanobacteria for the development of fertilizers, plant protection products and as well as for the use in agro-biotechnology. The physiological and biochemical potential of 22 strains of cyanobacteria and its influence on the efficiency of plant-microbe interactions were studied. Promising cyanobacterial strains Nostoc sp. ACSSI 57, Desmonostoc muscorum ACSSI 149, Desmonostoc muscorum ACSSI 091 can be recommended for development of biofertilizer. Strain Nostoc calcicola ACSSI 82 is promising for the development of biopreparations with herbicidal action. Strains Nostoc sphaeroides ACSSI 150 and Nostoc linckia ACSSI 271 can be used as a basis for biological stimulants and inhibitors of plant growth and development. It depends on the level of physiological parameters during cultivation in artificial media. Bacterization with one-month culture of a strain Nostoc linckia ACSSI 271 and a homogenate of the strain Nostoc sphaeroides ACSSI 150 significantly increased seed germination of Triticum aestivum L. (by 22.2 and 11.0%, p < 0.05). Strains of cyanobacteria Nostoc linckia ACSSI 271, Nostoc calcicola ACSSI 82 and Nostoc sphaeroides ACSSI 150 are able to affect the enzymatic activity and productivity of Ambrosia artemisiifolia L. Phytomass of plants after bacterization essentially (the least significant difference(0.5) is 2.31) reduced by 1.4-1.6 times (28.7-39.3%) compared to control (12.59 g/plant) and depending on the strain and its form of preparation. This suggests that bacterization with these strains is a powerful inhibitory factor for Ambrosia artemisiifolia L.