Continuous cultivation of a thermophilic bacterium Aeribacillus pallidus 418 for production of an exopolysaccharide applicable in cosmetic creams.

AIMS: The aim of this study was to evaluate the effectiveness of continuous cultivation approach for exopolysaccharide (EPS) production by a thermophilic micro-organism and the potential of the synthesized EPS for application in cosmetic industry. METHODS AND RESULTS: Study on the ability of Aeribacillus pallidus 418, isolated as a good EPS producer, to synthesize the polymer in continuous cultures showed higher production in comparison with batch cultures. The degree of the EPS in the precipitate after continuous cultivation significantly increased. Non-Newtonian pseudoplastic and thixotropic behaviour of EPS determines the ability of the received cream to become more fluid after increasing time of application on the skin. CONCLUSIONS: This study demonstrates a highly efficient way for production of EPS from a continuous growth culture of A. pallidus 418 that have many advantages and can outperform batch culture by eliminating time for cleaning and sterilization of the vessel and the comparatively long lag phases before the organisms enter a brief period of high productivity. The valuable physico-chemical properties of the synthesized EPS influenced positively the properties of a commercial cream. SIGNIFICANCE AND IMPACT OF THE STUDY: EPSs from thermophilic micro-organisms are of special interest due to the advantages of the thermophilic processes and nonpathogenic nature of the polymer molecules. However, their industrial application is hindered by the comparatively low biomass and correspondingly EPS yield. Suggested continuous approach for EPS could have an enormous economic potential for an industrial scale production of thermophilic EPSs.

Emulsifying power of mannan and glucomannan produced by yeasts.

Subject of study was the colloid chemical properties of the biopolymers mannan, synthesized from strain Rhodotorula acheniorum MC, and glucomannan, synthesized from strain Sporobolomyces salmonicolor AL(1). Their emulsifying capacity was studied in model systems of aqueous solutions in concentrations from 0.5% to 2.5% with regard to the aqueous phase. Emulsions of the direct type (oil/water) with 50% oil content were obtained. A disperse system with 2.5% glucomannan had 100% intact emulsion in the centrifugation test, while for the system with mannan, this indicator was 72%. Lab cream emulsions were obtained with glucomannan and with the emulsifiers Rofetan N/NS and Arlacel 165 used in the cosmetics industry. It has been established that under standard testing conditions, cream-like emulsions with 2.0% glucomannan have stability indicators comparable to these of 5.0% rofetan N/NS and 5.0% Arlacel 165. The samples with different concentrations of glucomannan showed a pseudo-plastic behaviour, as the highest viscosity was shown by the emulsion with 2.0% stored at 45 degrees C. The newly synthesized exopolysaccharides had a distinct emulsifying power and can be applied in the cosmetic and food industries.

Nutrient medium optimization for rosmarinic acid production by Lavandula vera MM cell suspension.

The overall effect of NH(4)NO(3), KNO(3), and KH(2)PO(4) on the biosynthesis of rosmarinic acid and cell biomass by Lavandula vera MM cell suspension was studied by the method of the full factor experiment. Polynomial regression models were elaborated to give a quantitative description of the processes of biosynthesis of rosmarinic acid (Y(1)) and cell biomass (Y(2)) as a result of the variation of the concentration of NH(4)(+), 0.09 g/L < or = X(1) < or = 0. 23 g/L; NO(3)(-), 2.44 g/L < or = X(2) < or = 3.02 g/L; and KH(2)PO(4), 0. 170 < or = X(3) < or = 0.425 g/L. Optimization procedures according to the modified Simplex method allowed us to establish the optimal conditions for the biosynthesis of rosmarinic acid by Lavandula vera MM: X(1*) = 0.09 g/L; X(2*) = 3.02 g/L, and X(3*) = 0.170 g/L, where Y(1)max = 1786.74 mg/L (27 times higher compared with the cultivation in the standard Linsmayer-Skoog medium). As a result, modified ingredients of the Linsmayer-Skoog nutrient medium were applied for the cultivation of Lavandula vera MM to achieve a maximum yield of rosmarinic acid.

Preparation and preliminary characterization of exopolysaccharides by yeast Rhodotorula acheniorum MC.

The effects of various carbon and nitrogen sources on the synthesis of exopolysaccharides by Rhodotorula acheniorum MC were studied. The dynamic viscosity of cell-free culture broths during exopolysaccharide synthesis were measured. The highest values for the viscosity (10.14 MPa.s) and crude polysaccharide productivity (6.6 g/L) were obtained in a medium supplied with 5% sucrose. Ammonium sulfate was the most favorable nitrogen source for exopolysaccharide synthesis. The value of pH played a determinant role, and the obligatory condition for exopolysaccharide production was low (pH 1.7-2.0) during the fermentation. The chemical composition and sugar constituents of the crude exopolysaccharides were determined. Mannose was the main monosaccharide component, and its concentration was the highest (69.13%) in the crude exopolysaccharide synthesized in the medium that included 5% sucrose as a carbon source.

Production of an exopolysaccharide by Antarctic yeast.

Psychrophilic Antarctic yeasts produce polysaccharides in different concentrations. According to morphological, cultural, physiological and biochemical characteristics, the best producer strain was identified as Cryptococcus flavus A(51). The highest values for viscosity (59.1 mPa s) and crude polysaccharide productivity (5.75 g/L) were obtained in a medium containing 5 % sucrose and 0.25 % (NH(4))(2)SO(4), at 24 degrees C for 6 d. The chemical composition and sugar constituents of the crude exopolysaccharide were determined (92.5 % saccharides, 3.34 % protein, and 4.16 % ash). The monosaccharide composition of the exopolysaccharide obtained from C. flavus strain AL(51) was established (55.1 % mannose, 26.1 % glucose, 9.60 % xylose, 1.90 % galactose). The microbial biopolymer has a high molar mass and homogeneity: 82 % of it had M 1.01 MDa.

[Pharmaceutical studies of intramammary formulations prepared with Pharmachem rifampicin]. / Niakoi farmatsevtichni prouchvaniia na intramamarni preparati, prigotveni s rifampitsin "Farmakhim".

Investigations were carried out on the medicines mastiriphin--intramammary syringes, (Mf) in two variants "A" and "B", meant for the treatment of acute mastitis with cows and also mastiriphin depot--intramammary syringes (Mf-depot), as well as two variants with indications for subclinical mastitis cows, containing both medicines in 10 g with 80,000 VI rifampicin, SEC "Pharmachem". Experiments were carried out for determining the stability of the medicines at different pH. The investigations were carried out with 23 lactating and 22 non-lactating cows. Both the degree of retention and the velocity of elimination of rifampicin from the milk and the lactic secretion. It was proved in vitro that rifampicin is stable in a neutral milk milieu (pH 7) in the course of 24 hours, and while in acid or alkaline milieu it was quickly eliminated Mf "A" in the case of intramammary introduction created high bacteriostatic (therapeutic) concentrations in the milk of the lactating animals till the sixth (eighth hour, whereas Mf "B" and the imported analogue rifamasten, provided twice as high levels of antibiotic. Mf-depot "B" introduced in a intramammary way with non-lactating cows was retained in the lactic secretion between 15 and 20 days. The quarantine time limits for using the milk taken from cows, treated in an intramammary way, proved to be 72 hours.

Comparative study of texture of normal and energy reduced sponge cakes.

The complete sucrose elimination and its replacement by microencapsulated aspartame (Nutra Sweet) and bulking agents (sorbitol, wheat starch and wheat germ) on the physical and textural sensory characteristics of two diabetic sponge cakes against a control sponge cake was studied. Mathematical and statistical methods were used and regression models worked out, describing the physical and textural characteristics of the three sponge cakes and their values were optimized. The effect on the porosity, springiness, volume and shrinkage of sponge takes was substantial and depended on the amount of the added ingredients. The diabetic sponge cake containing wheat germ showed the least physical and sensory deviations against the control sponge cake. The energy value of the diabetic sponge cakes against the control one was reduced with 25% for the ordinary sponge cake without sucrose and with 29% for sponge cake without sucrose containing wheat germ.

L-ascorbic acid in nonenzymatic reactions. I. Reaction with glycine.

The influence of the water content, molar ratio, time and temperature on the formation of nondialysable melanoidins produced by the interaction of L-ascorbic acid and glycine has been studied. The isolated polymers have been characterized by spectrum analysis and fractionated using gel chromatography. The rate constants of the reaction for temperatures of 90 degrees C, 100 degrees C and 110 degrees C have been calculated and are (0.84 +/- 0.29) x 10(-5) x s-1, (1.33 +/- 0.14) x 10(-5) x s-1 and (5.30 +/- 0.37) x 10(-5) x s-1, respectively. The activation energy of the reaction has been determined to be 106.07 +/- 32.47 kJ/mol.

[Toxicity of sodium monensin for pigs]. / Prouchvaniia vurkhu toksichnostta na monenzin-natrii pri praseta.

Studied were the acute and subchronic toxicity of monensin-Na in pigs. The investigations were carried out with elancoban-100, containing 10 per cent monensin-Na. A total of 46 pigs were used, weighing 15 to 60 kg. The preparation was applied individually via the nose or with the feed. It was found that nasally at 5 mg/kg the preparation did not lead to intoxication; rates of 10 and 20 mg/kg proved toxic, and a dose of 30 mg/kg was lethal. Feed containing 300 ppm of monensin-Na given but once led to intoxication and death with part of the animals. Pig tolerated well continuous (33 days) intake of feed that contained the sodium salt of monensin in concentrations of 120 and 240 ppm - no changes in the general status and behaviour were observed, nor were there any deviations in the morphologic and biochemical composition of the blood. It was demonstrated that the low amounts of monensin stimulated the weight gain of pigs. On the other hand, the clinical picture of the intoxication consisted in going off feed, higher pulse and respiration rates, involvement of the nervous system (depression of the nociceptive, eye closure, and ear reflexes, paresis of the hind limbs, and in severe cases - of the forelimbs too), hematuria in most of the animals, higher SGPT activity, and delayed ESR. Morphologically, there were vascular and slightly manifested degenerative changes in the parenchymal organs, red to brown urine in the bladder, strongly enlarged gallbladder, and catarrhal and hemorrhagic gastroenteritis. Histologically, there was granular and fatty degeneration of the kidneys, liver, and heart, hyperemia, perivascular and pericellular edema and degenerative changes in the glial cells of the berebrum, cerebellum, and medulla oblongata.

[Use of a broth made of the subepidermal layer of pig skin as feed]. / Izpolzuvane na bul'on ot podepidermalen sloi na svinski kozhi kato furazh.

Studied was a broth received from the T. Dokov leather factory in Etropole, prepared of swine skin subepidermal layer (BSSS). As many as 28 samples of BSSS were studied with regard to crude protein, crude fats, and aldehyde and peroxide numbers. The tolerability of BSSS was tested on a total of 150 Wistar albino rats after storing at various temperatures. Studied were also 10 batches of BSSS in fresh state (up to the 24th hour after receiving from the factory) as well as at intervals of up to 10 days in air-tight condition, at temperatures of 4 to 8 degrees C; 18 to 20 degrees C; and 37 degrees C. BSSS was administered orally, undiluted, at the rate of 3 ml/100 g body mass. The subchronic toxicity of BSSS was examined with two species of animals--pigs and broiler birds. BSSS was found to contain 12.2 to 14 g% proteins and 12.57 to 42.0 g% fats. When stored at 37 degrees C in nonsterile conditions its shelf life is but 24 hours, and at 4 degrees C it can be kept up to 10 days. It was tolerated well by rats, birds, and pigs when offered in fresh state. When mixed with other feed it did not lower the appetite of animals and could replace about 25-30 per cent of the daily protein ration. This, in turn, did not lead to changes in the white and red blood cell counts and in the biochemical composition of blood nor to changes in the internal organs and the striated muscles.

[Pharmacological and clinico-pharmacological studies of diazepam powder in suspensions]. / Farmakologichni i kliniko-farmakologichni prouchvaniia na diazepam-pulvis za suspenziia.

Studied was the preparation diazepam-pulvis for suspension (DPS) with regard to its tranquillizing and myorelaxing doses, inhibiting the aggression, and preventing the stress conditions in domestic animals and birds. It was established that at oral application to pigs at rates of 1 to 2 mg/kg body mass DPS produced a pronounced tranquillizing effect, while at 3 mg/kg it led to myorelaxation as well. In sheep tranquillizing effect was seen when amounts of 3 to 5 mg/kg body mass were used, and myorelaxation was achieved with 6.6 to 13.2 mg/kg. In male calves tranquillization was manifested after doses of 3 mg/kg body mass were applied. In hens the tranquillizing dose was found to be 3 mg/kg body mass, and the myorelaxing one--4 mg/kg; in cocks the respective doses were 5 and 7 mg/kg body mass. At the rate of 3 mg/kg body mass DPS was found to enhance the thiopental-sodium narcosis. When offered to pigs at 2 mg/kg body mass in admixture with the feed DPS led to tranquillization and suppression of the active and passive defense response. No full prevention of cannibalism could be achieved. The daily administration in the course of 30 days with the ration of bull-calves at the rate of 3 mg/kg body mass was shown to calm the animals under loose housing in boxes and affect favourably their weight gain. Admixed with the feed of cocks at 5 mg/kg DPS suppressed aggressiveness.

[Tolerance for tetraolean i.m. and the blood levels in agricultural animals]. / Ponosimost na tetraolean i. m. i kruvni niva pri selskostopanski zhivotni.

Studied was a drug formula of tetraolean for i/m application, containing tetracycline hydrochloride and oleandomycin phosphate in a 2:1 ratio, produced by the Antibiotic Works, Razgrad, and released in flasks of 500 mg and 1.0 g. It was followed up with regard to its tolerable serum concentrations for rabbits, calves, pigs, and horses. It was found that in therapeutic amounts tetraolean was well tolerated and did not lead to local and general disturbances. In higher doses it was found to form transient oedema in the site of injection. Intramuscularly, tetraolean was well absorbed in the site of application, and, according to the animal species, it developed proper plasmal therapeutic concentrations at the following rates: calves--20 mg/kg body mass at 12-hour intervals; pigs--10 mg/kg at 6-hr intervals, or 20 mg/kg at 12-hr intervals; horses--10 mg/kg at 12-hr intervals or 20 mg/kg at 24-hr intervals.

Differential binding of IgG and of a HIV gp41 peptide by the B chain and A chain globular head sequences of C1q, respectively.

Two individual globular head regions (ghA and ghB) of the heterotrimeric C1q molecule (containing A, B, and C chains) were expressed in a bacterial expression system using a coproduction with the bacterial chaperone GroESL. The purified proteins were soluble and monomeric, as shown by gel-filtration analysis. No association into homotrimers was seen, which indicates that the ability to form heterotrimers is coupled with the discrimination against homotrimeric self-association. The individual globular heads retained their binding activities toward two ligands bound by the whole C1q molecule, i.e., IgG and the peptide P(601-613) derived from the HIV envelope glycoprotein gp41. The differential binding activities displayed for these ligands indicated a degree of structural independence of the binding sites from the regions responsible for heterotrimerization. It was found, using single chain recombinant anti-C1q Abs, that the binding sites on C1q for IgG and gp41 do not overlap, and this observation is also consistent with the view that specialization between the C1q polypeptide chains takes place within the C1q molecule regarding their ligand-binding activities.