Liquid culture method

The standard methods for detection of MTb include acid-fast bacilli (AFB) smear and conventional and liquid culture methods. The AFB smear is rapid, but has a poor sensitivity of 20% to 80%. Another challenge with the AFB smear is that it cannot distinguish MTb from nontuberculous mycobacteria (NTM), such as M. avium-complex (MAC). This distinction is important because disseminated MAC and MTb are both common infections in persons with AIDS. Culture methods for the detection of MTb are sensitive, but growth detectable by standard methods may require 6 to 8 weeks in a culture. Growth often occurs more quickly in liquid culture than with conventional methods, but can still require weeks. With these limitations of culture methods, there was great enthusiasm for nucleic acid testing as a rapid, sensitive method for detection of MTb, especially given the needs to rapidly isolate patients with active, untreated disease and to initiate prompt therapy, particularly in immunocompromised hosts. 

Plant cell, tissue, and organ culture can be performed by either solid or liquid culture methods, however, in order to scale up the culture to the level of industrial processes, the liquid culture method must be employed. 

Recently, pilot bioreactors as large as 20 kl have been constructed in the research laboratories of Japan Tobacco and Salt Co. and in those of Nitto Denko Co. Solid culture methods were used in large scale pilot experiments for the production of tobacco cells, and liquid culture methods were used in the production of Panax ginseng cells. An outstanding example of cell suspension culture in a pilot scale bioreactor (750 1) was the production of shikonins by Mitui Petrochemical Industries. In all these examples, various technologies have been used to improve the productivity of the metabolites. 

A. D. Conger, A simple liquid-culture method of growing plants, Proc. Fla. State Hort. Soc. 77, 536-537 (1964). 

Briefly stated, the production of chloramphenicol by the surface culture method involves inoculating a shallow layer, usually less than about 2 cm, of a sterile, aqueous nutrient medium with Streptomyces ver)ezuelae and incubating the mixture under aerobic conditions at a temperature between about 20° and 40°C, preferably at room temperature (about 25°C), for a period of about 10 to 15 days. The mycelium is then removed from the liquid and the culture liquid is then treated by methods described for Isolating therefrom tne desired chloramphenicol. 

The application of near-IR spectroscopy for real-time monitoring of glucose, lactic acid, acetic acid and biomass in liquid cultures of microorganisms of the genera Lactobacillus and Staphylococcus has been recently published [76]. The NIR spectrum acquired by the optical-fibre probe immersed in the culture is exploited using a partial least squares (PLS) calibration step, a classical method for IR techniques. 

Long Z, Nimura N, Adachi M, Sekine M, Hanai T, et al. 2001. Determination of D- and L-aspartate in cell culturing medium, within cells of MPTl cell line and in rat blood by a column-switching high-performance liquid chromatographic method. J Chromatogr B 761 99-106. 

LG Rice, PF Ross, J Dejong. Evaluation of a liquid chromatographic method for the determination of fumonisins in com, poultry feed and Fusarium culture material. J AOAC Int 78(4) 1002-1009, 1995. 

R Ueno, T Aoki. High-performance liquid chromatographic method for the rapid and simultaneous determination of sulfamonomethoxine, miloxacin and oxolinic acid in serum and muscle of cultured fish. J Chromatogr B 682 179-181, 1996. 

In the 1950s, systematic methods were developed for taking cells directly from the tissues of whole animals and inducing them to grow as single cells in liquid culture. 

Cell cultivation has been conducted within aqueous fluid droplets embedded in a non-immiscible carrier liquid. This method that was conducted in a Si-glass microchannel was used to generate monoclonal antibodies [312]. In addition, human connective tissue progenitor (CTP) cells and human bone marrow-derived cells were cultured within PDMS channels [164], Cell culture for fibroblasts has been possible even under an AC field [896],... 

Bacterial enzymes are mostly produced in liquid-surface cultures. For fungi, solid-surface or submerged culture methods are employed. Submerged cultures are used in reactors of 10000-1000001 or greater volume 38). Mashes are usually composed of mixtures of carbohydrates. The processes are usually performed batchwise. 

Thin-Layer Chromatography (TLC) is a rapid and simple technique to detect several amines. This was one of the first techniques used to determine biogenic amines in foods (Halasz et al. 1994). Recently, a simple and rapid qualitative TLC method to determine the ability of bacteria to produce biogenic amines in liquid culture media containing the amino acid precursor was described by Garci a-Moruno et al. (2005). 

From the above results, it was apparent that for the production of hydrolyzable tannins using such liquid cultures (hairy root, adventitious root and shoot) further investigations will be required. Concerning the production of flavan-3-ols contained in the roots of this plant, the hairy root culture was the most useful method of those tested. The constitution of the flavan-3-ols found in the plant and the hairy roots and shoot cultures of P. mruri arc very similar to that observed in leaves of Thea sinensis (green tea) (97). Cultures of P. mruri might also have the same pharmacological effects as those expected from tea leaves (eg. 98,99). 

A. Induction of hairy roots by co-culture method, Infected segments were cultured on 1/2 MS solid medium containing 500 mg/1 Claforan at 25 °C in the dark. B The selected hairy root clone that demonstrated typical hairy root morphology. The hairy roots were cultured in MS liquid medium at 25 C in the dark for 4 weeks. C The regenerated shoots from the hairy (left) and adventitious (right) roots. The shoots were cultured on MS solid medium at 25 C under 16 hr/day light. 

In the proposed new method, microorganisms suspended in a liquid culture are incubated at 37 °C for 20 min in the absence or presence of an antibiotic, using the same drug concentration as is present in the accepted agar plate method. Respiratory activity (breathing) is then measured by a new electrochemical method. If respiratory activity is < 90% of the control measurement, made in the absence of antibiotic, the microorganism is susceptible to the antibiotic. The new method requires only 25 min, and can therefore provide results (and effective treatment regimes) much more rapidly than the accepted method. 

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