Dandelion Taraxacum officinale L. As a Promising Tool for Bio-Diagnostics of the State of the Urban Environment

The need to expand the list of organisms used in environmental biodiagnostics arises from the variety of pollutants and types of man-made effects on the biosphere. The choice of available test organism should be based on easily detectable and differentiable sensitivity to factors, high reproducibility of seed material, alignment of the genetic line used by the gene pool and phenotype. The paper presents the results of the soil contamination of urban agglomeration study by the bioindication and biotesting method using a dandelion as a bioindicator plant and a test organism. Within the study, the generation of dandelion was obtained and investigated for applicability in biotesting. During the first stage of the study, soil samples were taken in the influence zone of VOAO Khimprom and near the 2nd Prodol’naya avenue of Volgograd. Germination of dandelion seeds showed noticeable differences in growth rates both in comparison with control and in comparison, of prototypes with each other. At the end of the first stage, numerous apomictic seed offspring were obtained to excrete the aligned genetic lineage of test organisms. The expansion of the list of contaminated locations by counting the territories adjacent to the VMK Krasnyi Oktyabr’ showed the detected differentiated physiological reaction of test organisms grown in experimental soil samples. The results of the study confirm the postulate on soil contamination of urban locations with physiologically active pollutants and also characterize the used plant as a sensitive and easily reproducible test organism under artificial conditions. During the two-year experiment the possibility of selecting the genetic lineage Taraxacum officinale with predictable and monotonous properties was proved due to the tendency of this species to apomixis.

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Screening of Actinomycetes from Soil for Antibacterial Activity

Nepal Journal of Biotechnology ◽

10.3126/njb.v8i3.33664 ◽

2020 ◽

Vol 8 (3) ◽

pp. 102-110

Author(s):

Shailesh Budhathoki ◽

Anima Shrestha

Keyword(s):

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Test Organism ◽

Inhibitory Effect ◽

Soil Samples ◽

Aureus Strain ◽

Methicillin Resistant ◽

Test Organisms

Actinomycetes are Gram positive, free living saprophytes which are distributed in soil as one of the major populations and are primary source of antibiotics. This study was carried out with a quest to isolate actinomycetes from soil samples of different places and assess their antibacterial activity. Isolation of actinomycetes was carried out by serial dilution of soil sample followed by spread plate method. The antimicrobial extract was extracted using ethyl acetate. Assessment of antimicrobial activity was performed by using Agar cup plate assay against test organisms (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Salmonella paratyphi, Bacillus subtilis, Staphylococcus aureus). Antibacterial activity was tested against Methicillin Sensitive Staphylococcus aureus and Methicillin Resistant Staphylococcus aureus in the isolates having effective inhibitory activity against Staphylococcus aureus. From 15 soil samples of 12 different locations, 121 actinomycetes isolates were isolated. Among them, 58 (47.9%) isolates were inhibitory against at least 1 test organism in primary screening, of which 22 isolates effective against more than 1 test organism was chosen for secondary screening. Out of them, 8 were inhibitory against 2 test organisms while 14 were inhibitory against 3 test organisms. Staphylococcus aureus was found to be the most susceptible test organism with its susceptibility against 12 actinomycetes isolates. Among 12 isolates effective against Staphylococcus aureus, 10 were found to have an inhibitory effect against Methicillin Susceptible Staphylococcus aureus while 6 were found to have inhibitory effect against Methicillin Resistant Staphylococcus aureus strain. The findings of this study highlight the inhibitory potential of actinomycetes and the need for further investigation for obtaining novel antimicrobial agents from actinomycetes from various unexplored areas.

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Bioaerosol Exposure Method for Package Integrity Testing†

Journal of Food Protection ◽

10.4315/0362-028x-59.7.768 ◽

1996 ◽

Vol 59 (7) ◽

pp. 768-771 ◽

Cited By ~ 10

Author(s):

SCOTT W. KELLER ◽

JOSEPH E. MARCY ◽

BARBARA A. BLAKISTONE ◽

GEORGE H. LACY ◽

CAMERON R. HACKNEY ◽

...

Keyword(s):

Particle Size ◽

Test Organism ◽

Hole Diameter ◽

Pseudomonas Fragi ◽

Integrity Testing ◽

Aerosol Exposure ◽

Exposure Method ◽

Test Organisms ◽

Organism Growth ◽

Bioaerosol Exposure

Test organism motility, concentration, aerosol exposure time, hole diameter and length were evaluated to determine their influence on microbial ingress into a flexible plastic pouch. Microtubes with 10- and 20-μm hole diameters and of 5- and 10-mm lengths were used as defects in 128 flexible pouches. A bioaerosol with a 2.68-μm mean particle size comprised of 102 or 106 CFU/ml source concentrations of motile or nonmotile Pseudomonas fragi TM 849 was introduced into a 119,911-cm3 chamber for exposures of 15 or 30 minutes. Six pouches showed test organism growth after a 72-h incubation period. Microbial ingress was significant (P < .05) for motile test organisms with source concentrations of 106 CFU/ml.

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ISOLATION AND CHARACTERIZATION OF ACTINOMYCETES FROM SOIL OF AD-DAWADMI, SAUDI ARABIA AND SCREENING THEIR ANTIBACTERIAL ACTIVITIES

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i10.15402 ◽

2017 ◽

Vol 9 (10) ◽

pp. 276 ◽

Cited By ~ 3

Author(s):

Gouse Basha Sheik ◽

Muazzam Sheriff Maqbul ◽

Gokul Shankar S. ◽

Ranjith M S

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Antibacterial Activity ◽

Antibacterial Activities ◽

Soil Samples ◽

Streptomyces Sp ◽

Crude Extracts ◽

Test Organisms ◽

Inhibition Zones

Objective: To isolate and characterize novel actinomycetes and to evaluate their antibacterial activity against drug-resistant pathogenic bacteriaMethods: In the present study, 19 soil samples were collected from different localities of Ad-Dawadmi, Saudi Arabia. Actinomycetes were isolated from these samples using serial dilution and plating method on Actinomycetes isolation agar supplemented with nalidixic acid and actidione to inhibit bacteria and fungi. Crude extracts of potential actinomycetes were produced by submerged fermentation. The antimicrobial activity of crude extracts of actinomycetes was tested against different bacteria using the agar well diffusion method. Characterization of the isolates was done by morphological, physiological and biochemical methods.Results: A total of 9 (47%) isolates of actinomycetes were isolated from 19 different soil samples tested. Among them, 4 (44%) isolates confirmed as Streptomyces sp. showed potential antimicrobial activity against one or more test organisms. Crude extracts were made from these 4 actinomycetes isolates(DOM1, DOM3, DP3, DP4)and tested for their antibacterial activities against 4 different clinical bacterial strains (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus). Crude extract from DP3 isolate showed highest antibacterial activity against all the four test organisms (28 mm, 21 mm, 20 mm and 18 mm) respectively and DP4 showed lowest antibacterial activity against all the four test organisms (14 mm, 12 mm, 0 mm, 6 mm) respectively. The highest zone of inhibition was shown by DP3 against Staphylococcus aureus (28 mm) and Escherichia coli was resistant for DP4. Most of the Inhibition zones produced by crude extracts showed significant differences when compared with control, tested against test organisms (P<0.05). Inhibition zones produced by DP3 and DOM1 against Staphylococcus aureus were 28 mm and 23 mm, respectively which were strong active when compared with control Ciprofloxacin (18 mm).Conclusion: Further studies for purification of bioactive metabolites and molecular characterization analysis of isolated Streptomyces sp. are in progress which would be helpful in discovering novel compounds of commercial value.

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State of Heavy Metals Pollution of Flooded Agricultural Land in the North Part of Republic of Srpska

Агрознање ◽

10.7251/agren1601019p ◽

2017 ◽

Vol 17 (1) ◽

pp. 19

Author(s):

Tihomir Predić ◽

Petra Nikić Nauth ◽

Bojana Radanović ◽

Alen Predić

Keyword(s):

Heavy Metals ◽

Soil Contamination ◽

Agricultural Land ◽

Total Content ◽

Soil Samples ◽

Available Phosphorus ◽

The North ◽

North Part ◽

Grid Points ◽

Phosphorus And Potassium

This paper presents the results of the research of soil contamination in flooded area located at the confluence of Bosna and Sava rivers. The sampling was performed according to a network of points Etrs89 reference European Network based on grid points of 500 m x 500 m. The total number of soil samples was 31 and 13 samples of sediment-mud. In the soil samples and sediment-mud samples various parameters were analyzed: pH H2O and 1 M KCl, humus (method by Tjurin), and the readily available phosphorus and potassium (AL method). The interpretation of total content of heavy metals in the soil was conducted according to Dutch Soil Remediation Circular (2009). The samples were analyzed for the total content of heavy metals: Pb, Cd, Cr, Ni, Zn, Cu (aqua regia digestion, AAS) and the elevated concentrations of Ni. However, Ni content in mud was from 240.5 mg/kg to 294.5 mg/kg, in soil it was from 128.9 mg/kg to 452.1 mg/kg. All mud samples were alkaline, and 79% of soil samples were alkaline and of neutral reaction. The analysis indicated that the flood in May 2014 was not caused by soil contamination with heavy metals, which however contributed to the increase of the overall content of these elements in the soil.

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Evaluation of the Larvicidal Potential of the Leaf Extracts of Hyptis suaveolens Poit against Anopheles Mosquitoes

Asian Journal of Research in Zoology ◽

10.9734/ajriz/2018/v1i229676 ◽

2018 ◽

pp. 1-9

Author(s):

Amaka, John I. ◽

Attah, D. Daniel ◽

Obisike, Victor U. ◽

Benedict, Aboje G.

Keyword(s):

Mosquito Control ◽

Larval Instar ◽

Test Organism ◽

Phytochemical Screening ◽

Leaf Extracts ◽

Anopheles Mosquitoes ◽

Lc50 Value ◽

Hyptis Suaveolens ◽

Test Organisms ◽

Layer Chromatography

This study evaluated the larvicidal potential of the ethanolic and aqueous leaf extracts of Hyptis suaveolens Poit on the 4th larval instar of laboratory-reared Anopheles spp at varying concentrations of 0.1ml, 0.2ml, 0.3ml, 0.4ml and 0.5ml for specified periods of 24hrs, 48hrs and 72hrs. Qualitative phytochemical screening of the leaf extracts identified bioactive components like alkaloid, saponin, phenol, anthraquinone and flavonoid. The LC50 and LC90 values obtained indicate that the ethanolic leaf extracts of Hyptis suaveolens Poit had the greatest toxicity on the test organisms within 24hrs of exposure at median LC50 value of 0.485ml compared to the LC50 value of 0.625ml by its aqueous extract. The relative median potency estimates indicate that within 24 hrs, the ethanolic Hyptis suaveolens Poit was 0.161 times more potent on the test organism than aqueous Hyptis suaveolens Poit. The result of this research, therefore, underscores the efficacy of Hyptis suaveolens Poit as an eco-friendly alternative in Anopheles mosquito control. It is, therefore, recommended that quantitative phytochemical screening, application of column chromatography as well as thin layer chromatography be carried out on the extracts to isolate and purify toxic phytochemicals with larvicidal potentiality.

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SOIL CONTAMINATION IN PUBLIC SQUARES IN BELO HORIZONTE, MINAS GERAIS, BY CANINE PARASITES IN DIFFERENT DEVELOPMENTAL STAGES

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652013000400002 ◽

2013 ◽

Vol 55 (4) ◽

pp. 229-231 ◽

Cited By ~ 7

Author(s):

Luciane Madureira Ribeiro ◽

Ruth Massote Dracz ◽

Lanuze Rose Mozzer ◽

Walter dos Santos Lima

Keyword(s):

Soil Contamination ◽

Developmental Stages ◽

Minas Gerais ◽

Soil Samples ◽

Fecal Samples ◽

Belo Horizonte ◽

The City ◽

Recreation And Leisure

SUMMARY To evaluate soil contamination by parasites in different developmental stages in public squares used as recreation and leisure areas for children in Belo Horizonte (MG, Brazil), 210 soil samples and 141 canine fecal samples were collected from 42 squares in the city. These samples were analyzed by the Caldwell and Caldwell technique and the Hoffman, Pons, and Janer technique. Of the samples analyzed, 89 (42.4%) soil samples and 104 (73.5%) fecal samples were contaminated with Ancylostoma sp., Toxocara sp., Trichuris sp., or Dipylidium sp. eggs; Giardia sp. cysts; or Isospora sp. oocysts. The commonest parasite was Ancylostoma sp., found in 85% soil and 99% fecal samples, followed by Toxocara sp., found in 43.7% soil and 30.7% fecal samples.

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FUNGICIDAL ACTION AS AFFECTED BY INTERACTION OF NICKEL CHLORIDE, NABAM, ZINEB, AND ZINC SULPHATE

Canadian Journal of Botany ◽

10.1139/b61-041 ◽

1961 ◽

Vol 39 (3) ◽

pp. 519-530 ◽

Cited By ~ 2

Author(s):

F. R. Forsyth ◽

C. H. Unwin

Keyword(s):

Zinc Sulphate ◽

Early Blight ◽

Fungicidal Activity ◽

Test Organism ◽

Brown Rot ◽

Nickel Chloride ◽

Fungicidal Action ◽

Chloride Hexahydrate ◽

Wettable Powder ◽

Test Organisms

Protectant fungicidal action of mixtures of nabam, zineb, nickel chloride, and zinc sulphate was evaluated by means of a "microbeaker method" and the slide germination method, using as test organisms the fungi causing leaf rust of wheat, crown rust of oats, early blight of tomatoes, and brown rot of peaches. All of the fungicides tested were more effective against the two rusts than against the organisms causing early blight and brown rot. The relatively insoluble nickel ethylenebisdithiocarbamate was much less effective than the other chemicals tested. Ratios (w/w) of nickel chloride hexahydrate to zineb around unity and to nabam plus zinc sulphate from 2–10 to 1 showed an unfavorable effect on fungitoxic activity against urediospores of P. recondita. The ratio showing greatest antagonism varied, depending on the test organism used and whether or not tankmix or wettable powder zineb was used. The formation of nickel ethylenebisdithiocarbamate in the aqueous solution and its low fungicidal activity adequately explain the results obtained.

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Single- and multi-species toxicity testing with nematodes.

Ecology of freshwater nematodes ◽

10.1079/9781789243635.0010 ◽

2021 ◽

pp. 298-322

Author(s):

Sebastian Höss

Keyword(s):

Caenorhabditis Elegans ◽

Test Organism ◽

Toxicity Testing ◽

Single Species ◽

Risk Assessments ◽

Freshwater Sediments ◽

Nematode Communities ◽

Model Ecosystems ◽

Test Organisms ◽

Experimental Approaches

Abstract This chapter discusses the utility of nematodes in experimental ecotoxicology, and specifically in the study of freshwaters. Drawing on reports in which nematodes were used as test organisms in single-species tests as well as studies investigating nematode communities in model ecosystems (i.e. microcosms), the suitability of nematode-based experimental approaches in prospective and retrospective risk assessments of chemicals in freshwater sediments is examined. Several examples are presented of the use of Caenorhabditis elegans as a test organism in single-species bioassays, in order to demonstrate the versatility of this nematode for ecotoxicological investigations.

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Some Principles of Microbiological Turbidimetric Assays of Antibiotics

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/62.4.951 ◽

1979 ◽

Vol 62 (4) ◽

pp. 951-956

Author(s):

Robert A Rippere

Keyword(s):

Linear Response ◽

Test Organism ◽

Limited Range ◽

Liquid Media ◽

Agar Diffusion ◽

Assay Procedure ◽

Test Organisms ◽

Effective Use

Abstract Turbidimetric methods for determining the potency of antibiotics are inherently more accurate and more precise than are comparable agar diffusion procedures, but assays conducted in liquid media are subject to degradation from less than ideal conditions to a much greater extent than are diffusion methods. The relationships between test organisms, antibiotics, and assay concentrations are discussed. A valid assay procedure must produce a linear response with an adequate slope (–0.4 to –1.2) by the test organism to increasing concentrations of drug; such linear response normally occurs over a limited range of concentrations. Criteria used to select photometers that offer the greatest advantages to analytical microbiologists are described, with guidelines for the most effective use of the chosen instrument.

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