A high performance liquid chromatographic process was developed for betacyanin and betaxanthin pigments in a fermented red beet root extract. The method employs a reverse-phase microparticular C& column, ion pairing, and a methanol-water mobile phase, using a solvent gradient program. Spectrophotometric evidence and an enzymatic method were used to unequivocably identity peaks obtained from LC chromatograms. This accurate method for betalains separation and quantification was rapid and efficient. This method of assay enables the stability of the colorant in drug forms to be monitored routinely.

1. Diaminopimelate epimerase from a soluble extract of Bacillus megaterium N.C.I.B. 7581 was purified about 25-fold by fractionation with ammonium sulphate and chromatography on calcium phosphate gel-cellulose. The product was impure but was unstable on further purification. 2. Quantitative assay methods for the enzyme were devised in which meso- or ll-diaminopimelic acid may be the substrate. 3. Between 25 degrees and 45 degrees at pH7.0 enzyme action leads to an equilibrium mixture containing 65% meso-isomer and 35% ll-isomer. 4. The initial rate of epimerization was 2-3 times as fast with ll-diaminopimelic acid as substrate as with the meso-isomer; a number of other amino acids were not racemized by the enzyme. The Michaelis constants at 37 degrees were 6.7mm (ll-isomer) and 100mm (meso-isomer); with both substrates enzyme activity was maximal at pH7-8. The relative rates of epimerization of ll-diaminopimelic acid at 25 degrees , 37 degrees and 45 degrees were 0.77:1.00:1.15. 5. A thiol compound (of which 2,3-dimercaptopropan-1-ol was the most effective) was needed as an activator of the purified enzyme. 6. Carbonylbinding reagents and several other compounds did not inhibit diaminopimelate epimerase. 7. Pyridoxal phosphate did not stimulate enzymic activity even in preparations that had been almost completely freed of derivatives of vitamin B(6) (as shown by microbiological assay).

No abstract

No abstract

Propolis extract O/W emulsions, formulated with self-emulsifying bases are prepared. Type and optimal concentration of excipients (bases, consistency agents, solubilising factors) are chosen to obtain stable emulsions with desirable macroscopic properties, satisfactory consistency compatible with cutaneous application, in wound healing.