Synthetic Liquid Medium Research Articles

Degradation of Synthetic Glucose-Ammonium Tartrate Liquid Medium during Autoclaving

"Degradation of Synthetic Glucose-Ammonium Tartrate Liquid Medium During Autoclaving." Mycologia, 76(1), pp. 161–162Key Words: ammonium-tartrate mediaculture media

Effects of culture density on the kinetics of germ tube formation in Candida albicans.

The relationship between culture density or phase of growth at 24.5 degrees C and the ability of Candida albicans to form germ tubes when shifted to 37 degrees C was investigated. Evidence is presented demonstrating germ tube production from liquid synthetic medium cultures at all phases of growth. Previous studies reported that only cells from stationary phase cultures were competent to form germ tubes. Comparisons between exponential and stationary phase cultures indicate more rapid and more synchronous germ tube production from cells growing in the exponential phase.

A standardized monitor for the control of ethylene oxide sterilization cycles.

The resistance of spores of B. subtilis var. niger produced in liquid synthetic medium and exposed to ethylene oxide on a nylon surface, has been shown to the almost identical to that for spores produced on a traditional solidified complex medium with exposure to the sterilant on aluminium foil. The use of short lengths of nylon tube as carriers allowed easy production and handling, with self-protection of the spore-bearing surface. Addition of a dye provided visual evidence of inoculation without affecting resistance to ethylene oxide. Such a monitor is suitable for use as a standardized biological challenge in routine ethylene oxide sterilization cycles.

Biosynthesis of flavor compounds by microorganisms 4. Characterization of the major principles of the odor of Pleurotus euosmus

The volatile constituents of Pleurotus euosmus, grown on synthetic liquid medium, have been enriched and analysed by gas chromatography, sniffing analysis and coupled gas chromatography-mass spectrometry. Linalool and coumarin were identified as main compounds (900 resp. 2460/ug/l), and were found to be responsible for the intensive sweet flowery odor of the cultures.

Growth and sporulation of Beauveria bassiana and Metarhizium anisopliae in a basal medium containing various carbohydrate sources

Naturally occurring isolates of two entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae, pathogenic to the pecan weevil, Curculio caryae, were cultured in flasks of a liquid synthetic culture medium containing one of 22 individual carbohydrate sources to determine growth and sporulation responses. B. bassiana grew best on d-melizitose but sporulated best on d-sucrose, d-trehalose, and d-glucose. M. anisopliae grew best on d-mannose but sporulated best on i-inositol and glycerol. B. bassiana grew least on l-rhamnose but M. anisopliae grew least on d-arabinose. Both fungi sporulated least on d-sorbose. Both fungi utilized d-trehalose, a major component of insect hemolymph.

Extracellular β-malonoglucan from Penicillium erythromellis

Penicillium erythromellis grown statically in liquid synthetic medium produced an exocellular polysaccharide, which could be precipitated with ethanol (fraction A), composed mainly of glucose and malonic acid. From this fraction the demalonylated polysaccharide (fraction C) and the polysaccharide in the acid form (fraction D) were obtained. Optical rotation, infrared spectroscopy, Smith degradation and gas-liquid chromatography of the alditol acetates formed revealed that fraction A was a β -glucan, predominantly 1 → 6 linked, containing 2 malonyl hemiester groups for every 5 glucose residues (equivalent weight 481.7). A polysaccharide was extracted with water from the mycelium mat which did not precipitate with alcohol but was precipitated with FeCl 3 (fraction B). The composition of this fraction was found to be similar to that of fraction A.

Isolation of a variant of Candida albicans.

During the course of Candida albicans antigen production, a variant of this organism was encountered which did not produce hyphae at 37 degrees C. Presented here are some of the characteristics of this variant. It produces hyphae at 25 degrees C on cornmeal agar and synthetic medium plus N-acetylglucosamine and Tween 80. At 37 degrees C, it does not produce hyphae on these media, although C. albicans normally does produce hyphae under these circumstances. In liquid synthetic medium, this variant does not produce hyphae at 37 degrees C. The variant strain was analyzed for DNA, RNA, protein content, and particle size. After 50 to 70 h in balanced exponential-phase growth, particle size distribution was narrow, and there were no differences in the DNA, RNA, or protein content per particle in the two strains. When balanced exponential-phase cultures were brought into stationary phase, both strains contained the same amount of DNA per cell.

Further evidence for sequential action of amphotericin B and 5-fluorocytosine against Candida albicans.

Experiments were designed to determine the nature of amphotericin B (AMB)-5-fluorocytosine (5-FC) synergism against strains of Candida albicans susceptible to either drug alone. AMB strongly inhibited cell uptake of 14C-labeled 5-FC during incubation in a synthetic liquid medium. After several hours, however, this inhibition was dramatically released. Onset of 14C-5-FC uptake correlated with the known kinetics of AMB decay. These findings support the concept of sequential drug action proposed earlier. AMB apparently acts first and essentially alone until it approaches depletion. Experiments with a 5-FC-resistant mutant indicated that AMB interferes with transport of 5-FC to the cell interior.

Calorimetric studies of microbial growth: Quantitative relation between growth thermograms and inoculum size.

Heat evolution during growth of bakery yeast was studied in a heat-conduction calorimeter. Growth thermograms observed for yeast grown on liquid synthetic media with various inoculum sizes were compared. The quantitative relation between actual heat evolution and inoculum size was discussed in terms of the exponential growth function.

Combined action of amphotericin B and 5-fluorocytosine on pathogenic yeasts susceptible to either drug alone.

Amphotericin B (AMB)-5-fluorocytosine (5-FC) synergism has generally been observed in yeasts displaying 5-FC resistance. The present study was designed to assess activity of these drugs on yeasts showing susceptibility to 5-FC as well as AMB. Selected strains were incubated in a synthetic liquid medium with the test agents and viability or 14C-5-FC uptake was determined. Combinations of AMB and 5-FC continued to be inhibitory during the period that cultures treated with either drug alone were recovering from transient inhibition. In this sense, AMB + 5-FC exerted greater antifungal activity than either drug alone. However, combined activity did not involve AMB stimulation of 5-FC uptake by the organism. Results were indicative of sequential drug action.

The Potential for the Formation of Sclerotia in Submerged Mycelium of Sclerotium rolfsii

SUMMARY: Synchronous formation of sclerotia in Sclerotium rolfsii was induced in both solid and liquid synthetic media. Sclerotial initials were formed when mycelium was forced to pass from the submerged to the aerial growth phase in one of the following ways: (i) by removal of aerial mycelium with a scalpel; (ii) by growing the mycelium under a cover glass which was later removed; (iii) by inverting the agar in a Petri dish containing the fungal culture; (iv) by pouring a layer of agar over a colony. In all cases hyphae which emerged from the submerged phase produced many sclerotia synchronously. When grown in shaken liquid culture S. rolfsii did not produce any sclerotia while submerged, but when samples of the shaken culture were poured into a Petri dish 50 to 90 h after inoculation and incubated further, sclerotial initials were formed synchronously within 16 h on the liquid surface.

Development of a Defined Medium for Growth of Cercospora rosicola Passerini

A simple synthetic liquid medium containing a single amino acid, glucose, salts, trace metals, and thiamine was developed for cultivation of Cercospora rosicola Passerini. Thiamine was shown to be important to growth. Culture of C. rosicola Passerini in a chemically defined medium makes possible studies of (+)-abscisic acid biosynthesis and regulation.

THE HOST‐PARASITE RELATIONSHIP BETWEEN ZIZANIA CADUCIFLORA TURCZ. AND USTILAGO ESCULENTA P. HENN. II. USTILAGO ESCULENTA IN CULTURE

SUMMARYWith the exception of dikaryotization, the complete life‐cycle of Ustilago esculenta occurred on potato dextrose agar in culture. In liquid synthetic media, the maximum dry wt of sporidia was reached in 7 days at 27°C compared with 20 days for mycelium. The sporidia were hetero‐trophic for thiamine but not for biotin; the mycelium required neither vitamin. Mannitol supported the best growth of sporidia but only poor growth of mycelium; both stages grew well on fructose, glucose and sucrose. At suitable dilutions, an aqueous extract from culms of the host plant supported growth of sporidia and mycelium that was similar, or superior, to that on synthetic media. The implications of these results for the host‐parasite combination are discussed.

Beta-2-linked glucans secreted by fast-growing species of Rhizobium.

Fast-growing species of Rhizobium were found to secrete low-molecular-weight beta-2-linked glucans when cultured in synthetic liquid medium. These glucans are quite similar to beta-2-linked glucans produced by species of Agrobacterium. No reducing terminus was detected in these glucans.

Regenerated cell wall of carrot protoplasts isolated from suspension‐cultured cells

AbstractProtoplasts of Daucus carota L. cultured in a synthetic liquid medium resumed cell division after about 4 days of cultivation. During this lag period, nucleic acid and protein showed only slight increases but the protoplasts commenced cell‐wall regeneration soon after the removal of lytic enzymes. The originally spherical protoplasts became ellipsoidal before they underwent division. Radioactive glucose and myo‐inositol were readily utilized by the protoplasts. Most of the radioactivity, however, appeared in extracellular polysaccharides and only a small portion was deposited in the regenerated wall. The sugar composition of new cell wall, as studies by chemical analysis and incorporation of labelled precursors, was shown to be considerably different from that of normal cell wall.

β-1,3-1,4-Glucanase in sporenbildenden Mikroorganismen: II. Bildung von β-Glucan-Hydrolasen durch verschiedene Bacillus-Arten

Production of beta-1,3-1,4-glucan hydrolase (licheninase) was studied in 45 strains of Bacillus representing 17 various species using lichenin as substrate. It was found that the enzyme was produced by the strains of B. pumilus, B. subtilis, B. amyloliquefaciens, B. polymyxa, B. macerans, B. laterosporus and one strain of B. circulans. A new screening method based on application of a gel prepared from the cross-linked lichenin as an only source of carbon in the cultivation medium is presented. Using this method and methods using other cross-linked gels as carbon sources in a synthetic liquid medium, production of licheninase, amylase and cellulase by the strains tested is compared.

Effect of free fatty acids on aflatoxin production in a synthetic medium

The effects of fatty acids on aflatoxin B 1 production by Aspergillus parasiticus were investigated in vitro. Incorporation of mixed fatty acids from groundnut oil into a liquid synthetic medium stimulated aflatoxin B 1 production. Three individual saturated fatty acids, myristic acid, palmitic acid and stearic acid stimulated aflatoxin B 1 synthesis while two unsaturated fatty acids, oleic acid and linoleic acid tended to inhibit toxin synthesis. Lauric acid greatly inhibited the growth of A. parasiticus. The net amount of aflatoxin production in a food grain may therefore be expected to depend on the ratio of saturated to unsaturated fatty acids present.

Biosynthesis of cell-wall polysaccharides in cultured carrot cells

Biosynthesis of the cell wall in carrot cells (Daucus carota L.) cultured in a synthetic liquid medium was studied by measuring the incorporation of radioactive glucose and myo-inositol (MI). When the cells were fed with [(14)C]glucose in the presence of 0.01% MI, the label soon appeared in the neutral sugars in the cell wall but little radioactivity was found in the uronic-acid residues even after a prolonged incubation. On the other hand, radioactivity derived from [(3)H]MI was found to be distributed among uronic acids and pentoses but not in the hexose residues in the wall. The data indicate that MI is an important intermediate for the synthesis of acidic sugars in the wall of cultured carrot cells.

Thiobacillus ferrooxidansand the formation of acidity in simulated coal mine environments

Abstract Laboratory simulations have helped resolve several problems concerning the role of bacteria in producing acidic drainage from active and abandoned coal mines. It is well established that the bacterium Thiobacillus ferrooxidans oxidizes pyrite in synthetic liquid media and in flooded or agitated experimental simulations of coal mine environments. However, many geologists remain skeptical regarding the role of T. ferrooxidans in producing acidity below a near‐surface belt of soil water. We have demonstrated that T. ferrooxidans is capable of colonizing and acidifying a near‐neutral pH environment of crushed coal or overburden, without prior establishment of a pH‐dependent succession of bacteria. We have suggested that T. ferrooxidans may accomplish this by direct oxidation of pyrite. We have also shown that T. ferrooxidans catalyzes pyrite oxidation in the intermediate belt of the zone of aeration, although only for a limited period of time after rainfall infiltration. T. ferrooxidans was not found...

Bacterial Inhibitors Formed During the Adventitious Growth of Micro‐organisms in Chicken Liver and Pig Kidney

Inhibitory activity (detected by Bacillus cereus var. mycoides), identical with that encountered in survey samples, was induced in homogenized fresh chicken liver or pig kidney samples by incubating at 30°C. relative potency of each of three active components as detected by t.l.c./bio‐autography of extracts of freeze‐dried material was ascertained. Three strains of Streptococcus faecalis and a Lactobacillus sp. were responsible for production of the inhibitory activity, which was not produced by any of these organisms in synthetic liquid media.