scholarly journals The Roseobacter-group bacterium Phaeobacter as safe probiotic solution for aquaculture

Author(s):  
Eva C. Sonnenschein ◽  
Guillermo Jimenez ◽  
Mathieu Castex ◽  
Lone Gram

Phaeobacter inhibens has been assessed as a probiotic bacterium for application in aquaculture. Studies addressing the efficacy and safety indicate that P. inhibens maintains it antagonistic activity against pathogenic vibrios in aquaculture live cultures (live feed and fish egg/larvae), while having no or a positive effect on the host organisms, and a minor impact on the host microbiomes. While producing antibacterial and algicidal compounds, no study has so far found a virulent phenotype of P. inhibens cells against higher organisms. Additionally, an in silico search for antibiotic resistance genes using published genomes of representative strains did not raise concern regarding the risk for antimicrobial resistance. P. inhibens occurs naturally in aquaculture systems supporting its safe usage in this environment. Concluding, at the current state of knowledge, P. inhibens is a “safe-to-use” organism.

1970 ◽  
Vol 9 (1) ◽  
pp. 23-29 ◽  
Author(s):  
Abdullah Sarker ◽  
Shafiqur Rahman ◽  
Shakila N Khan ◽  
M Niamul Naser

Organic aquaculture utilizing probiotics for disease control and bioremediation has gained global acceptance in recent years. A preliminary study was conducted to isolate indigenous bacteria antagonistic to pathogenic vibrios as putative probiotics for shrimp hatcheries and grow-out systems. These efforts resulted in the isolation of a Gram-positive bacilli after screening thirty one water samples, collected from the coastal areas of the Bay of Bengal. This probiont, identified as Bacillus licheniformis exhibited vibriocidal activity in vitro against 60% of the Vibrio species isolated from the same water samples based on broad spectrum antagonistic and hydrolytic properties. In this study, we looked into the effects of pH, temperature, salinity, surfactants (Triton X114, Tween 80 and SDS) and EDTA on the vibriocidal property of the cell-free supernatant of the probiotic and observed that the antagonistic property was refractory to the surfactants used. The optimum activity of the cell-free supernatant was observed at 30°C, below and above which there was a marked decline in the inhibition. Neutral and alkaline pH ranges favored the antagonistic property while it was negligible at acidic ranges. The metal chelator EDTA nullified the antagonistic property at 0.01 mM concentration, the lowest tested, indicating the presence of a metal active group in the active fraction. The study suggests the potential of the selected bacterial isolate as a putative, antagonistic probiotic useful in the aquaculture systems of the tropics considering its broad antagonistic activity, higher activity in the neutral and alkaline pH and optimum activity at 30°C. Efforts are underway to purify and characterize the antagonistic compound in the cell-free supernatant. Key words: Probiotic; vibrios; Bacillus; shrimp; cell-free supernatant DOI: 10.3329/dujps.v9i1.7426 Dhaka Univ. J. Pharm. Sci. 9(1): 23-29 2010 (June)


2021 ◽  
Vol 16 (3) ◽  
pp. 53-68
Author(s):  
A.V. SKIPERSKIKH ◽  

The purpose of the research is to present how the carnival element in the regional policy is associated with the legitimating of power. Also made of the current state of the regional political process in some constituent entities of the Russian Federation, characterized by a high degree of carnivalization. As a result, the importance of the practices of the regional elite, resorting to game forms of their own positioning. The legitimacy of the regional power to depend on festive discourse. A routine political process in the constituent entities of the Russia does not evoke public emotions that have a positive effect on the legitimation of power. The demand for the politics of spectacle is also present in municipal political practices in a very dangerous epoch of COVID-19. A social organism that needs emotions, as well as control, does not experience serious transformations. In society penchant for spectacle, as well as the political class in the production of carnival events, there are deep historical roots, as well as the cultural specificity of a particular region. The points out that in the regional political process one can increasingly see accents on festivals. So, the government solves two important problems: the first one is a public request for a show, it is resolved in conditions of a rather unpleasant and unpromising accumulation of negative for the authorities due to the deterioration of the socio-economic situation in general, the second one is the production of the play solves the issues of legitimation regional and municipal authorities.


Aquaculture ◽  
2006 ◽  
Vol 253 (1-4) ◽  
pp. 140-147 ◽  
Author(s):  
Jiqiu Li ◽  
Beiping Tan ◽  
Kangsen Mai ◽  
Qinghui Ai ◽  
Wenbing Zhang ◽  
...  

Author(s):  
Vyacheslav Toropov ◽  
Elena Demyanova ◽  
Olga Shalaeva ◽  
Stanislav Sitkin ◽  
Timur Vakhitov

Whole-genome DNA sequencing of Lactobacillus D75 and D76 strains (Vitaflor, Russia) was performed using the PacBio RS II platform, followed by de novo assembly with SMRT Portal 2.3.0. The average nucleotide identity (ANI) test showed that both strains belong to the Lactobacillus helveticus, but not the L. acidophilus as previously assumed. 31 exopolysaccharide (EPS) production genes (nine of which form a single genetic cluster), 13 adhesion genes, 38 milk protein and 11 milk sugar utilization genes, 13 genes for and against specific antagonistic activity, aight antibiotic resistance genes, and also three CRISPR blocks and eight Cas I-B system genes were identified in the genomes of the both strains. The expression of some genes was confirmed. In fact, the presence of identified genes suggests that L. helveticus D75 and D76 are able to form biofilms on the outer mucin layer, inhibit the growth of pathogens and pathobionts, utilize milk substrates with the formation of digestible milk sugars and bioactive peptides, resist bacteriophages and show some genome-determined resistance to antibiotics, stimulate the host’s immune system. Pathogenicity genes have not been identified. The study results confirm the safety and high probiotic potential of the strains.


Symmetry ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 1894
Author(s):  
Husam N. Yasin ◽  
Siti Hafizah Ab Hamid ◽  
Raja Jamilah Raja Yusof ◽  
Muzaffar Hamzah

Graphical User Interface (GUI) testing of Android apps has gained considerable interest from the industries and research community due to its excellent capability to verify the operational requirements of GUI components. To date, most of the existing GUI testing tools for Android apps are capable of generating test inputs by using different approaches and improve the Android apps’ code coverage and fault detection performance. Many previous studies have evaluated the code coverage and crash detection performances of GUI testing tools in the literature. However, very few studies have investigated the effectiveness of the test input generation tools, especially in the events sequence length of the overall test coverage and crash detection. The event sequence length generally shows the number of steps required by the test input generation tools to detect a crash. It is critical to highlight its effectiveness due to its significant effects on time, testing effort, and computational cost. Thus, this study evaluated the effectiveness of six test input generation tools for Android apps that support the system events generation on 50 Android apps. The generation tools were evaluated and compared based on the activity coverage, method coverage, and capability in detecting crashes. Through a critical analysis of the results, this study identifies the diversity and similarity of test input generation tools for Android apps to provide a clear picture of the current state of the art. The results revealed that a long events sequence performed better than a shorter events sequence. However, a long events sequence led to a minor positive effect on the coverage and crash detection. Moreover, the study showed that the tools achieved less than 40% of the method coverage and 67% of the activity coverage.


2020 ◽  
Vol 38 (7) ◽  
pp. 941-955
Author(s):  
Vicente Sales-Vivó ◽  
Irene Gil-Saura ◽  
Martina Gallarza

PurposeThis study examines the triadic approach of value co-creation (VcC) in B2B relationships between the industrial manufacturer, its main supplier and its main client, by validating VcC as antecedent of Trust and Commitment, which, in turn, affect Satisfaction.Design/methodology/approachA model studies the association of VcC to Trust, Commitment and Satisfaction, the latter in its economic and social dimensions. The relationships in the model are empirically contrasted twice (with suppliers and clients) for a sample of 77 firms participating in an industrial panel, the Spanish Furniture Market Observatory.FindingsUsing PLS-SEM, results suggest that, in industrial B2B relationships, VcC acts as antecedent of Trust and, to a minor extent, of Commitment. It also has a positive effect on Social Satisfaction, the latter having a positive effect in turn on Economic Satisfaction.Research limitations/implicationsResults are limited to the Spanish furniture industry with a cross-sectional approach. The linkages between VcC and Commitment, as well as the differences found between Social Satisfaction and Economic Satisfaction, need replications.Practical implicationsThe study suggests that VcC is the core of B2B industrial relationships. VcC may also boost Economic Satisfaction.Originality/valueLiterature on VcC has been extensive in B2C and B2B mostly for service contexts; this paper contributes by bringing evidence from a B2B manufacturing context. At the same time, it depicts a triadic approach of VcC in B2B, by measuring the relationships with both the manufacturer's main supplier and main client. The study also contributes with evidence to the role played by Trust and Commitment in the relationship between VcC and two Satisfactions.


1991 ◽  
Vol 11 (2) ◽  
pp. 632-640 ◽  
Author(s):  
I Reveillaud ◽  
A Niedzwiecki ◽  
K G Bensch ◽  
J E Fleming

Superoxide dismutases (SOD) play a major role in the intracellular defense against oxygen radical damage to aerobic cells. In eucaryotes, the cytoplasmic form of the enzyme is a 32-kDa dimer containing two copper and two zinc atoms (CuZn SOD) that catalyzes the dismutation of the superoxide anion (O2-) to H2O2 and O2. Superoxide-mediated damage has been implicated in a number of biological processes, including aging and cancer; however, it is not certain whether endogenously elevated levels of SOD will reduce the pathological events resulting from such damage. To understand the in vivo relationship between an efficient dismutation of O2- and oxidative injury to biological structures, we generated transgenic strains of Drosophila melanogaster overproducing CuZn SOD. This was achieved by microinjecting Drosophila embryos with P-elements containing bovine CuZn SOD cDNA under the control of the Drosophila actin 5c gene promoter. Adult flies of the resulting transformed lines which expressed both mammalian and Drosophila CuZn SOD were then used as a novel model for evaluating the role of oxygen radicals in aging. Our data show that expression of enzymatically active bovine SOD in Drosophila flies confers resistance to paraquat, an O2(-)-generating compound. This is consistent with data on adult mortality, because there was a slight but significant increase in the mean lifespan of several of the transgenic lines. The highest level of expression of the active enzyme in adults was 1.60 times the normal value. Higher levels may have led to the formation of toxic levels of H2O2 during development, since flies that died during the process of eclosion showed an unusual accumulation of lipofuscin (age pigment) in some of their cells. In conclusion, our data show that free-radical detoxification has a minor by positive effect on mean longevity for several strains.


2013 ◽  
Vol 37 (1) ◽  
pp. 115-120
Author(s):  
Tasmia Farzana ◽  
Shafiqur Rahman ◽  
M Niamul Naser ◽  
Muhammad Manjurul Karim

The molecular basis of antagonistic activity of a number of probiotic bacteria was analyzed using plasmid curing method. Earlier, six bacteria having potential probiotic activity under laboratory conditions were screened from 96 isolates which were obtained from shrimp rearing environment from south-west coastal region of Bangladesh. Among the isolated probionts, five were subjected to plasmid curing method and three were found to harbor plasmids, as was revealed in an agarose gel electrophoresis. Curing of these plasmids demonstrated that the bacteria lost its antagonistic activity, indicating the activity could be plasmid-borne. The antagonistic activities of the rest two isolates however, were not plasmid-oriented as no plasmid was recovered from them. DOI: http://dx.doi.org/10.3329/jbas.v37i1.15688 Journal of Bangladesh Academy of Sciences, Vol. 37, No. 1, 115-120, 2013


2021 ◽  
pp. 93-99
Author(s):  
I. F. Bogatyrev

The relevance of studying the harmonization of industrial policy with other types of economic policy is determined, the structure of industrial policy is presented, the main directions of harmonization are noted. The external harmonization of industrial policy is analysed in detail on the example of competition policy. The main aspects of each of the policies are considered, their main differences are noted. Attention is focused on their possible mutual complementarity in order to achieve a higher positive effect from the implementation of each. The current state of harmonization in Russia is considered, in particular, the conclusion is made about the dominance of industrial policy over competition. The main problems of harmonization are highlighted, including the discrepancy between pre-set goals in industrial policy and the final results. The problem of small and medium-sized businesses in industry is identified, the factors hindering the development of subjects of these categories are formulated. 


2021 ◽  
Author(s):  
Sarah Kritzler ◽  
Maike Luhmann

Personality traits describe how people typically think, feel, and behave, and personality states describe how people think, feel, and behave in a given moment. In their daily lives, people often behave the way they typically do (they enact trait-congruent personality states), but occasionally behave differently from how they typically do (trait-incongruent personality states). Several theories propose that such incongruent personality states should be associated with undesirable outcomes such as less positive affect or more tiredness, but the current state of evidence is inconclusive and mostly based on one only personality dimension: extraversion. In this study, we contribute to filling important gaps in the literature by examining congruence of personality dimensions other than extraversion, considering characteristics of the situation, and modeling congruence with state-of-the-art response surface analyses. We aimed to manipulate perceived adversity and deception of the situation as well as state honesty-humility and state agreeableness in a prisoner’s dilemma paradigm. However, the manipulations had unexpected effects and were therefore considered unsuccessful. The study thus emphasized the difficulty of manipulating personality states, situation characteristics, and congruence in general. In pre-registered cross-sectional response surface analyses and specification curve analyses, we then examined how trait–state congruence and state–situation congruence were associated with cognitive performance in a numerical Stroop task, positive affect, and tiredness. Neither trait–state congruence nor state–situation congruence were associated with positive affect, tiredness, or cognitive performance. Overall, we therefore concluded that congruence may—if at all—only play a minor role in the associations between personality states and relevant outcomes.


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