Axenic cultures

Algal blooms in fresh water ponds occasionally poison livestock and waterfowl. Axenic cultures of Anabaena flos-aquae NRC 44-1 were shown to produce the toxic principle (5) which can be present in the algae and in the water of mature cultures (6). The discovery of the toxin was fortuitous in the sense that AChR agonists do not have a (known) constructive function in the algae evolution of the synthetic pathway was likely a by-product of metabolic pathways in the algae. The compound became evident only through its toxic effects on other organisms. 

Axenic cultures of dwarf spikerush (Eleocharis colorado-ensis) were established in 4 L aspirator bottles containing quartz sand and a synthetic culture medium. These were periodically drained and the effluent subjected to fractionation and bioassays. This crude leachate was passed through a C. cartridge to separate polar from nonpolar compounds. The nonpolar fraction was eluted from the cartridge with acetone and the solvent evaporated with gas. The polar fraction was lyophilized. Both... 

Bolla, R.I. (1987) Axenic culture of plant-parasitic nematodes problems and perspectives. In Veech, J.A. and Dickson, D.W. (eds) Vistas on Nematology. Society of Nematology, Hyattsville, Maryland, pp. 401-407. 

Inoculate via glass tube with axenic cultured cells, remove tube and seal dialysis tubing... 

Fries L (1975) Some observations on the morphology of Enteromorpha linza (L.) J. Ag. and Enteromorpha compressa (L.) Grev. in axenic culture. Bot Mar 18 251-253 Fukuhara Y, Mizuta H, Yasui H (2002) Swimming activities of zoospores in Laminaria japonica (Phaeophyceae). Fish Sci 68 1173-1181... 

Rosenberg, A. and Alexander, M. Microbial metabolism of 2,4,5-trichlorophenoxyacetic acid in soil, soil suspensions, and axenic culture, 7 Agric. Food Chem., 28 297-302, 1980. 

Studies on phytotoxicity of bibenzyl derivatives were extended to duckweed axenic cultures. Bibenzyls 19 and 20 as well as the synthetic analogs 23—28 were tested by triplicate in cultures of the small aquatic plant. Analogs 23—28 were synthesized to investigate the effect on phytotoxicity of oxygenated substituents (phenolic vs. phenolic methyl ether) and their location on the bibenzyl core structure. All synthesized analogs but... 

Work on the chemical structure and properties of the poisons from Alaska butter clam siphons, the hepatopancreas of California mussels, and axenic cultures of G. catenella carried on in the Biological Laboratories and with Rapoport at the University of California definitely established that the sea mussel did not alter the poison obtained from G. catenella. The poison from all three sources had identical structures (31). The situation with the Alaska butter clam may be different however in light of the different saxitoxin derivatives recently found in the dinoflagellates in that region. Perhaps the clam converts the sulfo and sulfate derivatives to the more toxic saxitoxin. 

However, axenlc cultures were grown in ESNW only, and only those extracts which supported the best growth in bacterlzed cultures were used in the axenic culture experiments. 

Table I. Allelopathic Effects of Cell-Free Filtrates of Axenic Cultures of Dominant Algae on Nondominant Algae...

Axenic cultures of Agalinis grown in the absence of a host develop few or no haustoria (4,11). Induction of this organ is rapid upon... 

PHARMACOLOGICAL ACTIVITIES AND CLINICAL TRIALS Alkaline phosphatase stimulation. Extract of the leaf, administered orally to adults, was active. Patients with subacute hepatic necrosis had negative workup, except for consumption of 15 tablets of the herbal extract per day for 4 months L Anthelmintic activity. Water and petroleum ether extracts of the dried oleoresin were active on Eimeria tenella in chicken - . Anti-amoebic activity. The resin of Larrea produced inhibitory activity at a concentration of 1 ppm on Entamoeba invadens PZ axenic cultures. The nordihydroguaiaretic acid activity was observed at 10" to 10" concentrations - . 

Matem U, Oberer L, Falchetto RA, Erhard M, Konig WA, Herdman M, Weckesser J (2001) Scyptolin A and B, Cyclic Depsipeptides from Axenic Cultures of Scytonema hofmanni PCC 7110. Phytochemistry 58 1087... 

Meharg AA, Caimey JWG, Maguire N (1997) Mineralization of 2,4-Dichlorophenol by Ectomycorrhizal Fungi in Axenic Culture and in Symbiosis with Pine. Chemosphere 34 2495... 

Bioconcentration of organic compounds by aquatic plants has received relatively little research attention. Curves showing uptake and loss of radioactivity by duckweed plants exposed to labelled compounds in axenic cultures are shown in Fig. 2. Rate constants and calculated equilibrium bioconcentration factors are shown in Table III. By comparison with fish data shown in Table I, the plants concentrated fenitrothion and fluorene rather poorly, and aminocarb surprisingly well. Lockhart et al. (14) presented a regression equation based on data from uptake curves ... 

Figure 2b. Uptake and depuration curves for cis- and trans-permethrin in laboratory studies with axenic cultures of duckweed.

TCDD (Matsumura and Benezet 1973). The organisms were maintained in liquid axenic culture,... 

G Harth, MA Horwitz (1999) An inhibitor of exported Mycobacterium tuberculosis glutamine synthetase selectively blocks the growth of pathogenic mycobacteria in axenic culture and in human monocytes extracellular proteins as potential novel drug targets, J Exp Med 189(9) 1425-1436... 

Stefels J, van Boekel WHM (1993) Production of DMS from dissolved DMSP in axenic cultures of the marine phytoplankton species Phaeocystis sp. Mar Ecol Prog Ser 97 11-18... 

In the present chapter, I will discuss the potential of EMF to influence weathering rates of soil minerals, and review experiments where the effects of EMF on dissolution of minerals have been investigated in axenic cultures, pot cultures and field experiments. I will then discuss the influence of the nutrient status of the trees on weathering induced by EMF and, finally, to what extent this process may influence the overall cycling of elements in forest ecosystems. 

In axenic cultures, some EMF can get access to non-exchangeable potassium and calcium reserves in micas such as phlogopite and vermicu-lite (Paris et al., 1995a, b, 1996). Application of limiting amounts of potassium and magnesium in the nutrient media increased the release of potassium from phlogopite, and seemed to be accompanied by increased exudation of oxalic acid by the EMF (Paris et al., 1995a, 1996). Exposure... 

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