Mycelia medium

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. 

This material was made up with distilled water to provide 41 g per liter, and the mixture was adjusted to pH 7.0 with potassium hydroxide solution. To the mixture were added per liter 5.0 g of calcium carbonate and 7.5 ml of soybean oil. 2,000 ml portions of this medium were then added to fermentation vessels, equipped with stirrers and aeration spargers, and sterilized at 121°C for 60 minutes. After cooling the flasks were inoculated with a suspension of strain No. ATCC 11924 of Streptomyces lavendulae, obtained from the surface of agar slants. The flasks were stirred for 4 days at 28°C at approximately 1,700 rpm. At the end of this period the broth was found to contain cycloserine in the amount of about 250 C.D.U./ml of broth. The mycelium was separated from the broth by filtration. The broth had a pH of about 7.5. Tests showed it to be highly active against a variety of microorganisms. 

The SF-837 strain, namely Streptomyces mycarofaciens identified as ATCC No. 21454 was inoculated to 60 liters of a liquid culture medium containing 2.5% seccharified starch, 4% soluble vegetable protein, 0.3% potassium chloride and 0.3% calcium carbonate at pH 7.0, and then stir-cultured in a jar-fermenter at 28°C for 35 hours under aeration. The resulting culture was filtered directly and the filter cake comprising the mycelium cake was washed with dilute hydrochloric acid. 

The mixture of broth and mycelium thus formed was then transferred under aseptic conditions to a 3-iiter fermentor containing 2 00 ml of a sterile fermentation medium having the following composition 60 g Cerelose (dextrose hydrate), 18 g soybean meal, 5 g distillers solubles, 12 g cornmeal and tap water in a sufficient amount for a 1,000-ml total volume, adjusted to pH 7.0 to 7.2 with potassium hydroxide. 

After seeding the nutrient medium with the preformed inoculum previously described, the mixture was subjected to agitation and aeration under aseptic conditions for 72 hours at 27°C to 28°C for the first 24 hours, then at 25°C to 26°C for the next 48 hours during this period, the pH was in the range of 6.4 to 6.8. Aeration was accomplished by cultivation under submerged conditions at an air flow rate of one volume of air per volume of medium per minute. After termination of the process, the mycelium was removed by filtration and the filtered broth found to contain 450 7of oleandomycin per ml of solution. 

The flasks are then placed on a reciprocating shaker (120 one and one-half inch cycles per minute) and mechanically shaken at 25°C for 3 days. The contents of the flasks are then pooled and, after the pH of the culture is adjusted to about 4 0.2 with sulfuric acid, filtered through Seitz filter pads to separate the mycelium from the fermented medium. 

After fermentation, large volumes of spent medium containing dtric acid and mycelium remain. 

The correct answer here is in both the medium and the mycelium. It is known that some 15% may remain in the mycelium immediately after harvesting. 

Usually the dtric add outweighs the biomass by a ratio of 5 1. The initial task is to remove the mycelium from the medium, a process usually carried out by rotary filtration. The wet biomass is crushed and rewashed to obtain most of the 15% dtric add contained within and the washings are added to the spent medium. 

Either a spore suspension or mycelium can be used to inoculate the production vessel. The medium contains a maximum glucose concentration of 15%. The upper limit reflects the low solubility of caldum gluconate which is normally about 4% at 30°C, but it can form supersaturated solutions up to about 15% without risk of predpitation. 

Penicillins, like most antibiotics, are secondary products whose synthesis is not directly linked to growth. The enzymes that produce secondary products are normally repressed or inhibited under conditions which favour rapid growth. In the early work on penicillin, Penicillium rwtatum was grown as a floating mycelium on about 2 cm depth of liquid medium. The mycelium absorbed nutrients from the medium and penicillin was excreted into the medium. The mycelium and spent medium are readily separated. 

Cyclic peptide from 11 amino acids. Preparation by fermentation of Tolypocladium inflatum Gams with addition of DL-a-aminobutyric acid to the fermentation medium. Isolation by homogenization of mycelium, extraction with 90 % methanol and column chromatographic purification. 

Experiments in 500 ml Erlenmeyer flasks and Fernbach flasks contained 200 ml and 1 L of EPl and EP2 medium respectively. Inocuia added to these cultures was 2 ml of spore suspension (5.0 optical density at 540 nm) for each 100 ml EP medium. All cultures were grown at 37°C in a shaking incubator (New Brunswik Sci. Co., USA), at 200 rpm. Then 10 ml of sample were withdrawn each 24 h during fermentation and immediately filtered through Millipore membranes of 0.45 pm pore size these cell-free filtrates were used for enzymatic assays and extracellular protein determinations by the Lowry method (14). Experiments in the 14 L fermentor (Microgen Fermentor New Brunswik Sci. Co., USA) were carried with lOL of fermentation medium EP2 and inoculum added was IL of mycelium grown 24 h in... 

Figure 5A,B. Northern analysis of an A. aculeatus multicopy transformant (A) compared to the wild type (B). RNA was isolated from the mycelium before (lanes 1), 6 h after (lanes 2) and 24 h after (lanes 3) transfer of the corresponding strains to minimal medium (MM) with 1 % apple pectin. The location of the rhgA transcript is indicated with an arrow.

The basal medium of Mandels (Mandels et al., 1976) was used with the following modifications it was buffered with 3 g/1 of sodium nitrate to pH 5.5 and supplemented with 1% w/v citrus pectin " Sigma" or other carbon sources. For enzyme production, 50 ml medium in 250 ml erlemneyer flasks were inoculatedwith spores (10 spores /ml ) exept for the non sporulating Pol 6 strain, where mycelium was used. The culture were incubated at 30° C on a rotary shaker (150 rev mn -1) for 5 days. The culture broth was filtered (Millipore 0.45 pm ) and the supernatant was analysed for pectinolytic activities, reducing sugars and proteins. 

The five flasks with each 100 mL of medium (precultures) were inoculated with mycelium of M. rammaniana from the agar plates using a sterile inoculation loop and incubated on a laboratory shaker with 5 cm agitation radius at 28 °C and 220 rpm for 3 days. 

Production. The inoculum grew vigorously in the rich yeast extract containing media and produced a thick viscous dispersion in the stirred tank bioreactor. No lignin peroxidase activity could be detected at this stage. When transferred to the 1000 1 production bioreactor, the mycelium of P.chrysosporium attached completely to the nylon wool sheets within a few hours after inoculation and the medium remained completely clear throughout the cultivation. The enzyme had to be harvested immediately after the maximal activity level was reached due to its... 

After finding the best conditions and nutrients for growth, requirements for optimal product formation must be determined. It was University of Wisconsin Professor Marvin Johnson and his student Jarvis who stated in their memorable 1947 paper on penicillin fermentation that We have not been able to devise a medium on which rapid mycelium growth and... 

The purification of bacterial constituents usually starts in a very conventional way with an extraction step of the crude broth at neutral or slightly acidic pH. Mycelium-forming organisms are separated by filtration, and the cell mass and the filtrate are extracted separately. For the liquid phase, adsorber resins allow high recovery rates of metabolites and low process costs due to repeated use of the resins. If liquid-liquid extraction has to be applied, medium or highly polar solvents are favored. Ethyl acetate is the solvent of choice, and only in few cases is butanol superior. To extract the moist cell material, ethyl acetate, acetone or dichloromethane/methanol can be used. 

Rhizopus arrhizus dead mycelium was found to be very active in organic solvents as a naturally immobilized lipase. Triglycerides hydrolysis and interesterification, esters and glycerides synthesis, natural flavour esters preparation and racemic mixtures resolution in pharmaceutical drugs synthesis are among the successfully designed processes, each of one with a specific reactional medium. 

The vegetative body is a thallus. It consists of filaments about 5 pm in diameter which are multi-branched or spread over or into the nutrient medium. The filaments or hyphae, can be present without cross walls as in lower fungi or divided into cells by septa in higher fungi. The total hyphal mass of the fungal thallus is called the mycelium. In certain situations during transition between asexual and sexual reproduction, various other tissue structures are formed, e.g. plectrenchyma (mushroom flesh). 

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