Biologically active substances (water soluble vitamins and minerals) were analyzed in 'Kombucha'-a curative liquor, produced by the so-called 'Kombucha cultivation' (Macedonian collection of microorganisms, No 734) in sweet black tea decoct. The water soluble vitamins in the Kombucha drink were separated and identified using thin layer chromatography (TLC) and quantified by the comparison of their chromatographic UV spectra with the reference compounds. Four soluble vitamins have been determinated to have the following concentrations: vitamin B 1 0.74 mg ml Ϫ1 , vitamin B 6 0.52 mg ml Ϫ1 , vitamin B 12 0.84 mg ml Ϫ1 and vitamin C 1.51 mg ml Ϫ1 . Mineral elements of nutritional and toxicological importance were determined in dissolved ash using atomic absorption chromatography (AAS). Mineral composition content involved determination of the essential elements: zinc, copper, iron, manganese, nickel and cobalt. Investigations of some toxic elements showed that lead and chromium were present in very small amounts, whereas cadmium was not found.

The spectrophotometric method (using PdCl2) for determination of hexoses was applied to samples of milk to determine the lactose content with previous estimation of the conditions for quantitative determination. The method was carried out on milk serum samples, obtained according to four different procedures, in accordance with literature data, to identify the one most suitable to application of the PdCl2 method. The experiments were undertaken on milk serum samples of different pH values, temperatures, and storage times. The possibility of application of the palladometric method was ascertained by statistical treatment of these results using the reference Luff−Schoorl method. The results of the investigations show that the first procedure (using Fehling I) for obtaining milk serum was the most suitable one for applying the PdCl2 spectrophotometric method and that the pH value, temperature, and time of storage did not influence the method and its ability to accurately determine the lactose content. Keywords: Lactose; milk serum; palladium chloride