Spirostomum
- Spirostomum ambiguum
- Spirostomum teres
[ref. ID; 6983]
Test system
24 hr-EC50 and 24 hr-LC50
Strains
Toxicants
2,3-dimethylphenol,
2,4-dimethylphenol,
2,5-dimethylphenol,
2,6-dimethylphenol,
3,4-dimethylphenol,
3,5-dimethylphenol,
1,2,3-trichlorobenzene,
1,2,4-trichlorobenzene,
2,3-dichlorophenol,
2,4-dichlorophenol,
2,5-dichlorophenol,
2,6-dichlorophenol,
3,4-dichlorophenol,
3,5-dichlorophenol,
2,3-dichloroaniline,
2,4-dichloroaniline,
2,5-dichloroaniline,
2,6-dichloroaniline,
3,4-dichloroaniline,
3,5-dichloroaniline,
2,4-dinitrophenol,
2,5-dinitrophenol,
2,6-dinitrophenol,
2,4-dinitroaniline,
2,4-dinitrochlorobenzene,
2,4-dinitrofluorobenzene.
Test design
Spirotox test (Nalecz-Jawecki & Sawicki, 1999).
Test containers were disposable 24-well microplates.
A diluent Tyrod solution (1:64). Tyrod solution (125 mg NaCl, 3.1 mg KCl, 3.1 mg CaCl2, 1.55 mg MgCl2, 15.6 mg NaHCO3 and 0.78 mg NaH2PO4 per litre of deionised water. Total hardness 2.8 mg CaCO3/l, pH 7.4+/-0.2).
A five-step dilution series was prepared in triplicate directly in the microplate wells, the ring of each well was greased with silicone fat. The microplate was then covered with the lid. After 24-hr incubation in the dark at 25 degrees C. Three replicates.
Measurements
Cell number.
Evaluations
EC50, LC50.
[ref. ID; 7062]
Test system
Development of a new low cost microbiotest
Strains
- SAW (S. ambiguum Warsaw) was supplied by Dr Nalecz-Jawecki from the Department of Environmental Health Sciences at the Warsaw University of Medecine in Warsaw, Poland.
- SAB (S. ambiguum Besse) was collected from a small pond in a pine forest near Besse-en-Chandesse in Auvergne, France.
- SAP (S. ambiguum Phalempin) was collected from a pond in the Phalempin forest in the North of France.
Test conditions
Temperature (15, 20, 25 degrees C). Light (darkness, continuous light). Medium (5 artificial media). Food type.
Measurements
Cell number.
Evaluations
An average generation time.
[ref. ID; 7202]
Test system
Regeneration
Strains
Toxicants/concentrations
Chloramphenicol (1x10E-5 - 1x10E-3 M), Colchicine (1x10E-6 - 1x10E-4 M), Cyanide (5x10E-4 - 5x10E-3 M), Ethidium Bromide 10-30 ug/ml), Iodoacetate (1x10E-6 - 1x10E-4), Mercaptoethanol (1x10E-5 - 1x10E-3 M), Sodium azide (1x10E-7 - 1x10E-5 M),
Test design
For an experiments, about 150 postdivision cells were selected and cut just behind the peristome with a sharp sterilized needle under a stereo binocular microscope. Fragments were exposed to different metabolic inhibitors for different time periods during the span of regeneration.
Anaerobic test for Iodoacetate: Growth medium was nitrogen-gas bubbled for 15-30 min and triple-cavity glass slides were used for the experiment.
Measurements
Appearance of the peristome in the aperistomal fragment, attainment of optimum size of the contractile vacuole, and restitution of the characteristic ciliary movement were taken as the markers for complete regeneration.
[ref. ID; 7449]
Test system
Inhibition of phagosome formation
Strains
From the Carolina Biological Supply Co., Burlington, NC.
Inhibitors
Cytochalasin A, B, C, D, E, J and dihydrochalasin B (Sigma Chemical Co., St. Louis, MO).
Test design
S. ambiguum were cultured in the dark with several stems of timothy hay and boiled wheat grains in Carolina spring water. All experiments were carried out using randomly selected, rapidly feeding cultures, and no attempt was made to selet cultures in specific growth phases. Ciliate suspensions were obtained by pipet collection of "piles" of feeding cells that had congregated around wheat seeds. These were diluted into 35x10 mm plastic Petri dishes containing the assay mixture. Room temperature (approx. 24 degrees C).
Measurements/observations
Phagosomes per cell.
Evaluations
Using the two-tailed Mann-Whitney test (Microsoft Statmost 2.5).
[ref. ID; 6111]
Test system
Acute toxicity (24-hr LC50)
Strains
The organisms was obtained, initially, from Stirone Stream (northern Italy), a freshwater environment free from known toxicants and, in particular, from heavy metals. The culture medium was constituted of boiled rice and wheat grain in 10 ml of filtered natural water. 20+/-1 degrees C, photoperiod of 16:8 hr light:dark.
Toxicant/concentrations
NiCl2/6H2O (0.13, 0.17, 0.21, 0.25 ppm).
Test design
Tissue culture plates with 24 wells, 3 replicates.
Measurements
Mortality or the survivorship.
Evaluations
LC50 using the probit method.
[ref. ID; 6838]
Test system
The effect of culture conditions for acute toxicity (24-hr LC50)
Strains
Originally harvested from an unpolluted pond in Puy-de-Dome (France).
Toxicants
CuSO4, HgCl2, CdCl2, K2Cr2O7, ZnSO4, Pb(NO3)2, thiram, carbaryl, lindane, parathion, parathion methyl, paraoxon, 2,4,6-trichlorophenol, and sodium pentachlorophenol (Na-PCP).
Test design
- Culture water: Three kinds of water were tested: Volvic mineral water (calcium 9.9 mg/liter, magnesium 6.1 mg/liter, potassium 5.7 mg/liter, chlorates 8.4 mg/liter, nitrates 6.3 mg/liter, sulfates 6.9 mg/liter, bicarbonates 65.3 mg/liter, pH 7.0); deionized water (pH 6.7); and distilled water (pH 5.7).
- Inoculum of ciliates: 2, 4, 8, and 16 ciliates per milliliter in 25 ml of culturing water containing 4 wheat grains.
- Temperature and light conditions: Temperature 8, 20, 25, 28 and 31 degrees C. Light condition light and darkness.
- Number of wheat grains on ciliate multiplication rate: Petri dishes containing respectively 1, 2, 4, and 8 wheat grains in 25 ml culturing water were inoculated with 4 ciliates/ml and covered to avoid evaporation. The dishes were maintained at 25 degrees C.
- Initial bacterial concentration on ciliate multiplication rate: Petri dishes containing the chosen culturing water and respectively 1, 2, 4 and 8 wheat grains without inoculating the media with S. teres.
- Acute toxicity test methods: Toxicity tests were performed at 25 degrees in polystyrene multiwells (1-cm diameter, 0.8-cm depth, and 0.5 ml capacity for each well) filled with 0.4 ml per well of the test concentration. Five ciliates per well. Each toxicity test consisted of a minimum of five dilutions and a control. Assays were conducted in duplicate for all concentrations and each one was repeated five times.
Measurements/observations
Mortality.
Evaluations
LC50 by probit analysis according to Finney (1971).