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The influence of different factors on biosynthesis of extracellular alpha-amylase of Aspergillus sp. 55 grown at submerged cultivation has been studied. The optimal composition of nutrient medium (1 g of starch and 0.5 g of NaNO3 per 1 l) was chosen. The enzyme preparation has a wide pH optimum of activity (4.5-9.0), thermooptimum at pH 6.5 was 60 degrees C, at pH 4.5 and 9.0--50 degrees C. The inhibitory effect of coordinative germanium compounds on amylolytic activity of the preparation was shown. The paper is presented in Ukrainian.

The paper deals with the capacity of the coordination germanium compounds with citric acid in a complex with some aminoacids (aspartic acid, methionine, cysteine, threonine, phenylalanine, L-glutamic acid) as bioligands to affect synthesis and activity of the proteolytic enzyme complex of Bacillus sp. 27 and Yarrowia lipolytica 2061. Thus, biscitrategermanium acid H2[Ge(H4Citr)2] and its complex with aspartic acid (HAsp)2 [Ge(H4Citr)2] can be used with success for inducing biosynthesis ofcaseinolytic (182.1 and 197.4%) and elastase (182.6 and 383.3%) activities of Bacillus sp. 27, respectively. Biscitrategermanium acid can be used to induce biosynthesis of caseinolytic (182.1 and 197.4%) and elastase (182.6 and 383.3%) activities (respectively) of Bacillus sp. 27. Biscitrategermanium acid with methionine induced biosynthesis of caseinolytic (127.6%) and haemoglobinolytic (110.0%) activities of Y. lipolytica 2061. The tested coordinative compounds could not induce activity ofproteolytic complexes of both microorganisms. The capacity of complexes of citrategermanium acid with aspartic acid, methionine, cysteine, threonine, phenylalanine in concentration of 0.1% to inhibit activity of proteolytic complex of Y. lipolytica 2061 can be used in further studies of the catalytic centre of enzymes.

The ability of the synthesized compounds of germanium with bioligands to affect the biosynthesis and activity of alpha-amylase and alpha-L-rhamnosidase has been studied. It was established the most complexes tested induced biosyntheis of alpha-amylase of Bacillus subtilis 147 (119-252%) with the exception of Pam (Pyracetam) and II (Ge-nicotinic-citric acid). At the same time the biosynthesis of alpha-amylase of Bacillus licheniformis 234 and alpha-L-rhamnosidase of Penicillium commune was inhibited by a number of synthesized compounds. The complexes IV (Ge-malonic acid) and VIII (Ge-nicotinamide-malonic acid) did not exert any effect on the biosynthesis of alpha-amylase however complex IV stimulated alpha-L-rhamnosidase biosynthesis on the 3rd day of producer cultivation. The study of influence of the studied germanium compounds on the activity of alpha-amylase and alpha-L-rhamnosidase gives every reason to suppose that they are the inhibitors of the above-mentioned enzymes.

Germanium complexes (IV) with succinic (H2Suc), oxyethyliminodiacetic (H2Oeida) and iminodisuccinic (H4Ids) acids as well as homo- and heteroligand germanium complexes (IV)--products of interaction of triammonium salt of oxyethylidendiphosphonic acid ((NH4)3HL) and oxyacids: tartaric (H4Tart), citric (H4Citr), trioxyglutaric (H4Toglut) acids have been synthesized. Composition of the obtained complexes: [Ge(OH)2(NaSuc)2].2H2O (I); [Ge(OH) (Oeida).H2O].H2O (II); [Ge(OH)2(NaHIds)2] (III); [Ge(OH)2(NH4)3HL) (H2Tart)] (IV); [Ge(OH)2(NH4)3HL) (H2Citr)] (V); [Ge(OH)2(NH4)3HL) (H2Toglut)] (VI); [Ge(OH)2((NH4)2HL)2] (VII); [Ge (OH)2((NH4)2HL)2] (VII); [Ge(OH)2 (H2O)2(NH4) HL] (VIII) has been determined. The capability of the synthesized compounds has been studied to affect synthesis and activity of the following enzymes: collagenase, alpha-N-acetylgalactosaminidase (alpha-GalNAc-ase) and alpha-galactosidase (alpha-Gal-ase). It has been established that the complexes II-VIII activate biosynthesis of alpha-Gal-ase and alpha-GalNAc-ase, while germanium dioxide (IX) and complex I possess considerable inhibiting effect on synthesis of the above enzymes. It has been also established that all the compounds except for IV increased the activity of both alpha-Gal-ase and alpha-GalNAc-ase. All the considered complexes demonstrated similar reaction with respect to collagenase: they inhibited both synthesis and activity.