Plant seeds and their use as test organisms for the assessment of toxicity of a model xenobiotic

Abstract This paper presents an overview of techniques utilizing natural phytoplankton for the detection of metal-Induced stress in the Great Lakes. Both field and laboratory procedures are designed to evaluate either structural changes or functional response of test organisms. This up-to-date compendium provides a choice of techniques, which permits a holistic assessment of the stress caused by toxic metals. Recently introduced techniques, such as normalized size spectra analysis, flow cytometry, and the evaluation of a continuous-flow system response to metal toxicity, are discussed in more detail to explore their future potential. Owing to their key position in the food web, high turnover rates, abundance, and sensitivity to environmental perturbation, phytoplankton serve as reliable early warning indicators of ecosystem deterioration and its restoration.

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A Standard Primary Toxicity Bioassay Using Daphnia Magna as a Test Species

Water Quality Research Journal ◽

10.2166/wqrj.1977.004 ◽

1977 ◽

Vol 12 (1) ◽

pp. 27-50 ◽

Cited By ~ 2

Author(s):

L.A. Behie ◽

J.E. Zajic ◽

D. Berk ◽

R.J.P. Brouzes ◽

V.A. Naish

Keyword(s):

Statistical Analysis ◽

Daphnia Magna ◽

Biological Indicator ◽

Pulp And Paper ◽

Toxicity Bioassay ◽

Simple Method ◽

Test Species ◽

Test Organisms ◽

Dilution Water

Abstract Although Daphnia magna have been widely used in the determination of the toxicity of various substances, there are no reports in the literature that describe a rigorous bioassay method using this organism as a test species. The test described herein involves the standariza-tion of various important aspects of the method such as the age of the test organisms, and the dilution water used for the preparation of the various toxicant concentrations. Also described is a simple method for the statistical analysis of the results. The sensitivity of the proposed bioassay is demonstrated by determining the toxicity of various pulp and paper effluents. Finally, extensive bioassays were carried out simultaneously with rainbow trout and Daphnia magna indicating that Daphnia are as good a biological indicator of acute toxicity as fish.

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Effect of Mercury on the Survival of Daphnia Magna

Water Science & Technology ◽

10.2166/wst.1990.0035 ◽

1990 ◽

Vol 22 (5) ◽

pp. 241-246 ◽

Cited By ~ 3

Author(s):

I. Brković-Popović

Keyword(s):

Life Span ◽

Daphnia Magna ◽

Abiotic Factors ◽

Total Hardness ◽

Chemical Characteristics ◽

Effect Concentration ◽

Test Organisms ◽

Lethal Time ◽

Two Temperatures ◽

Time Required

The median lethal time (LT) for each concentration of mercury was determined on the basis of mortality curves. Toxicity curves (i.e., the median life-span of Daphniamagna, LT 50, versus the concentration of mercury) for four tested conditions are shown. The experiments were carried out using two diluents of different total hardness (46 and 119 mg/l as CaCO3), at two temperatures (20°C and 25°C). A comparison of the LT 50s of the control organisms with the LT 50s of the test organisms at mercury concentrations of 0.0075 and 0.0050 mg. l-1 showed that the chemical characteristics and temperatures of the mediums tested did not affect the range of the ‘no effect' concentration. However, the incipient LC 50, and the time required for its appearance, did depend on the combination of the abiotic factors tested.

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Evaluation of a Domestic Steam Disinfector-Dryer Device for Disinfection of Health Care Workers’ Identification Lanyards

Workplace Health & Safety ◽

10.1177/21650799211012653 ◽

2021 ◽

pp. 216507992110126

Author(s):

Beverley C. Millar ◽

John E. Moore

Keyword(s):

Health Care ◽

Health Care Workers ◽

Culture Conditions ◽

Broth Culture ◽

Culture Methods ◽

Simple Method ◽

Diverse Range ◽

Nosocomial Pathogens ◽

Care Workers ◽

Test Organisms

Background Fabric lanyards are commonly worn by health care workers (HCWs) and are known to harbor infectious organisms and contribute to the transmission of infection to HCWs and patients. A diverse range of nosocomial pathogens have been found on lanyards, but there are very few studies describing how to successfully disinfect lanyards to break the chain of transmission. Recently, a steam disinfector-dryer device has come on the market, which performs rapid disinfection against nosocomial pathogens and also dries the contents of the device. It was the aim of this study to evaluate steam disinfection-drying as a method to eliminate pathogens from lanyards. Methods Thirty-eight strips of new, unused, and autoclaved polyester neck lanyards (4 × 2 cm) were inoculated with 30 (12 Gram-positive + 18 Gram-negative) bacteria and one yeast organism. The inoculated lanyard fabric (five organisms per lanyard strip) was placed into a steam disinfector-dryer device and disinfected for 5 minutes and dried for 30 minutes, in accordance with the manufacturer’s instructions. Following disinfection and drying, the presence of viable organisms on lanyard fabric was evaluated using enhanced microbiological broth culture methods for 48 hours. Control lanyard strips were treated with organisms and left at room temperature without undergoing disinfection and drying procedures. Findings Steam disinfection-drying eradicated all test organisms from treated lanyards, with no culturable organisms detected following disinfection-drying, even when employing enhanced bacteriological culture conditions. All test organisms remained viable on the control lanyards. Conclusion/Application to Practice Steam disinfection-drying offers a simple method of decontaminating lanyards, producing dry lanyards for immediate reuse. Occupational health practitioners and hospitals should consider assessing the feasibility of adopting this method in their settings to aid in breaking the chain of transmission of nosocomial pathogens via contaminated lanyards.

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Flavonoids in seeds and grains: physiological function, agronomic importance and the genetics of biosynthesis

Seed Science Research ◽

10.1017/s0960258500004372 ◽

1998 ◽

Vol 8 (4) ◽

pp. 415-422 ◽

Cited By ~ 97

Author(s):

Brenda Winkel Shirley

Keyword(s):

Secondary Metabolites ◽

Condensed Tannins ◽

Physiological Function ◽

Animal Feed ◽

Molecular Genetic ◽

Flavonoid Biosynthesis ◽

Human Consumption ◽

Genetic Studies ◽

Plant Seeds ◽

Reproductive Structures

AbstractFlavonoids are secondary metabolites that are present at high levels in most plant seeds and grains. These compounds appear to play vital roles in defence against pathogens and predators and contribute to physiological functions such as seed maturation and dormancy. At the same time, particular subclasses of flavonoids, such as the proanthocyanidins (condensed tannins), negatively impact the use of seeds and grains in animal feed and can add undesirable qualities to food products for human consumption. This article presents an overview of investigations into the physiological and agronomic aspects of seed and grain flavonoids as well as a review of molecular genetic studies, particularly in maize,Arabidopsisand soybean, where mutants deficient in flavonoid biosynthesis provide useful tools for stydying the metabolic machinery underlying the accumulation of these compounds in reproductive structures.

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Use of two fungal strains as test organisms for the evaluation of relative nutritive value in cereals and legumes

Qualitas Plantarum ◽

10.1007/bf02590308 ◽

1976 ◽

Vol 25 (3-4) ◽

pp. 317-329 ◽

Cited By ~ 9

Author(s):

M. Mohyuddin ◽

A. K. Kaul ◽

T. R. Sharma ◽

E. -G. Niemann

Keyword(s):

Nutritive Value ◽

Fungal Strains ◽

Test Organisms ◽

Relative Nutritive Value

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Design and synthesis of novel benzimidazoles containing 1,2,3-triazolesas in vitro, anticancer and anti-oxidant agents

Research Journal of Chemistry and Environment ◽

10.25303/2511rjce104109 ◽

2021 ◽

Vol 25 (11) ◽

pp. 104-109

Author(s):

Gullapelli Kumaraswamy ◽

Ravichandar Maroju ◽

Srinivas Bandari ◽

Gouthami Dasari ◽

Gullapelli Sadanandam

Keyword(s):

Spectroscopic Methods ◽

Moderate Activity ◽

Design And Synthesis ◽

Anti Cancer ◽

Excellent Activity ◽

Test Organisms ◽

Anti Oxidant ◽

High Yields ◽

Cancer Activity

A novel series of 2-(1-((1-substitutedphenyl-1H-1,2,3- triazol-4-yl)methoxy)ethyl)-1-((1-substituted phenyl- 1H-1,2,3-triazol-4-yl)methyl)-1H-benzo[d]imidazole (3a-j)derivatives was synthesized in moderate to high yields. The structures of all the synthesized compounds were characterized by 1HNMR, 13CNMR and Mass spectroscopic methods. The title compounds were screened for their anti-oxidant activity and anti-cancer activity. The cancer activity results reveal that the compounds 3j, 3b and 3f are showing promising activity and remaining compounds exhibited moderate activity against all the tested cancer cell lines. The anti-oxidant activity also shows that the compounds 3c and 3d have shown excellent activity and remaining compounds were also found to exhibit moderate activity against the test organisms employed.

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Investigating the process of electrocoagulation in the removal of azo dye from synthetic textile effluents and the effects of acute toxicity on Daphnia magna test organisms

Journal of Water Process Engineering ◽

10.1016/j.jwpe.2021.102485 ◽

2022 ◽

Vol 45 ◽

pp. 102485

Author(s):

Carlos Eduardo Lach ◽

Camila Schwarz Pauli ◽

Aline Scheller Coan ◽

Edesio Luiz Simionatto ◽

Luciano André Deitos Koslowski

Keyword(s):

Acute Toxicity ◽

Daphnia Magna ◽

Azo Dye ◽

Textile Effluents ◽

Test Organisms

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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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