Mycelia chromatography

Polyethers are usually found in both the filtrate and the mycelial fraction, but in high yielding fermentations they are mosdy in the mycelium because of their low water-solubiUty (162). The high lipophilicity of both the free acid and the salt forms of the polyether antibiotics lends these compounds to efficient organic solvent extraction and chromatography (qv) on adsorbents such as siUca gel and alumina. Many of the production procedures utilize the separation of the mycelium followed by extraction using solvents such as methanol or acetone. A number of the polyethers can be readily crystallized, either as the free acid or as the sodium or potassium salt, after only minimal purification. 

Paper partition chromatographic methods have been widely applied to the analysis of tetracyclines (128, 129). Pharmaceutical aqueous suspensions for oral use are acidified with HC1 and diluted with methanol. Crystalline formulations are dissolved only in methanol. A paper chromatographic method for TC determination in pharmaceutical preparations is based on the complexation of the antibiotic with a mixture of urea and disodium edetate on paper at pH 7.4. Urea helped in the separation of degradation products and led to the formation of well defined spots (130). Samples from fermentations must be acidified with oxalic acid to liberate TC from the mycelium. TC in filtrates may be precipitated in saturated solution of sodium tetraphenyl borate, precipitate dissolved in ethyl or butyl acetate and applied for paper chromatography. Various solvent systems and hRp values for paper chromatography are given in Table 4. 

The fungus Helirastylum piriforme ATCC 8992 is cultivated for 3 d at 28 "C in a medium (pH 6.8-7.0) consisting of 3.5 % glucose. 2% peptone and 0.3 % corn steep liquoT in tap water, on a rotary shaker. The wet mycelium harvested from the culture broth (100 ml) is suspended in 100 mL of deionized water and 50 mg (0.13 mmol) of finely divided lithocholic acid (3) are added. The mixture is incubated for 2 d at 28 JC on a shaker. Extraction of the incubation mixture with EtOAc yields a mixture of hydroxylation products. The principal component 4 is purified by column chromatography on silica gel and isolated by crystallization from EtOAc and then from acetone yield 20 mg ( 40%) mp 171.5- 172.5 C. 

The structure of another nonadride, heveadride (6.26), obtained from the mycelium of Helminthosporium heveae was established from its spectroscopic properties and its oxidative degradation by potassium permanganate to a series of acids, the methyl esters of which were separated and identified by gas chromatography-mass spectrometry. 

Figure 2. High performance liquid chromatography profile of centrifuged whole broth and mycelium extract. Column Waters Assoc. 1-125 protein analysis column (30 cm x 7.8 mm). Mobile phase 0.05 M phosphate buffer, pH 6.9. Flow rate 1.0 ml/min, Detector UV at 210 nm.

Kucera J (2004) Fungal mycelium - the source of chitosan for chromatography. J Chromatogr B 808 69-73... 

Partially purified serologically actiye fractions, ACI-B, MHI-B and RNI-B, were separated by affinity chromatography with a con A sepharose column from the supernatant of disrupted mycelium fluid of cyl indrospora, JM. hiemal is and J,. nigricans, respectively. These active fractions contained mannose as their... 

The technique for the isolation of nicotinic acid depends on the starting material. In most cases, a preliminary hydrolysis is required either with acids or alkalies. The extractions are more complete if the material is rendered free of lipids, a necessary step when working with animal products. The free acid is extracted from the hydrolysate with organic solvents such as hot alcohol. It may then be separated as such from the organic solvent extract or in the form of an ester or as the copper salt the free acid can be recovered from the copper salt by H2S treatment. Purification is carried out by crystallization from concentrated water or alcohol solutions. Nyc et al. extracted nicotinic acid from the mycelium of Neurospora with acetone. Subsequent purification steps included the formation of the barium salt, acidification with H2SO4 and adsorption of the free nicotinic acid on charcoal. Elution was accomplished with 4% aqueous aniline and the final purification step involves recrystallization from a i 4 mixture of acetic acid and benzene. Leifer et al. have applied paper chromatography with M-butanol saturated with ammonia to separate nicotinic acid from contaminating materials. 

From these preliminary results, we undertook the elaboration of a new protocol to purify a PLTP from Mucor mucedo mycelium. According to other results on other organisms, we try other phases for liquid chromatography. Our aim was to purify and to characterize, for the first time, a PLTP from this... 

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