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Biomedical subjects

A P Balatti

Publications and source records attributed to A P Balatti.

At least 19 recordsLinked to original sources
PubMed1983

[Production of glucose isomerase by Streptomyces phaeochromogenes].

The production of glucose isomerase was studied in the Streptomyces phaeochromogenes NRRL B-3559 strain. The influence of the medium composition and the aeration conditions was determined Selection of colonies was necessary to obtain the best results. A grey colony proved to be the most productive one. It was necessary to use the frozen inocula in order to obtain steady reproduction values. It was possible to achieve the maximum enzymatic level (1600 UE/1 min) using a CoCl2. 6H2O concentration of 0.18 g/l. The aeration studies conducted in a mechanically stirred fermentor showed results comparable to those obtained in shaker flasks, operating at 550 rpm and using an air flow of 1 1/1 min. The culture proved to properly aerated since both the cellular oxygen uptake and oxygen demand were similar (Table 1).

Aerobiosis↗
PubMedDate not supplied

[Influence of amaranth on the production of alpha-amylase using Aspergillus niger NRRL 3112].

In this paper the influence of the amaranth seed meal and the aeration conditions on the alpha-amylase production by Aspergillus niger NRRL 3112 were studied. The assays of selection of culture medium were carried out in a rotary shaker at 250 rpm and 2.5 cm stroke. The aeration conditions were studied in a mechanically stirred fermentor New Brunswick type. A concentration of alpha-amylase of 2750 U.Dun/ml was achieved at 120 h with a dry weight of 8.0 g/l, using a base medium with 5.0 g/l Amaranthus cruentus seed meal. In the experiment performed in a New Brunswick fermentor, the highest value was 2806 U.Dun/ml. This result was obtained after 120 h, operating at 300 rpm and an airflow of 1 l/l. min. in a limited dissolved oxygen concentration. It was determined that the increase in the agitation rate was not favorable to the enzyme production, despite that an increase was verified in the dissolved oxygen. The morphology of the microorganism, in long and ramified hyphae, was the critical factor to obtain higher levels of alpha-amylase.

Amaranth Dye↗
PubMedDate not supplied

[Influence of the sterilization technic and culture media components on the growth and dissociation of Brucella abortus strain 19 in submerged cultures].

Submerged cultures of Brucella abortus strain 19 were studied in shaking flasks. The influence of the sterilization methods and the medium composition on the bacterial yield and cellular dissociation were studied. The selected medium was as follows (amounts in g/l): casein pancreatic hydrolizated 30; yeast extract 10; glucose, 30; sodium phosphate dibasic anhydrous 3,3; sodium monobasic monohydrate 9. Cell concentration of 8 . 10(10) viable cell/ml was obtained after 48 hours when the medium components were separated and sterilized at 121 degrees C for 20 min in autoclave.

Bacteriological Techniques↗
PubMedDate not supplied

[Growth and polysaccharide formation in Sinorhizobium meliloti strains in an air-lift-type fermentor. Effect on nodulation velocity in alfalfa plants].

In this paper the influence of the exopolysaccharides produced by Sinorhizobium meliloti strains on the nodulation rates in alfalfa plants has been considered. The experiments were performed in a rotary shaker and in an air-lift type fermentor. Different Sinorhizobium meliloti strains were used. Bacterial growth rates were determined by viable cell counts. Exopolysaccharide concentration was determined by precipitation with ethanol. It was observed that maximum cell concentration was in the order of 1 x 10(10) cell/ml and exopolysaccharide content was approximately 11 g/l. The experiments performed with alfalfa plants in a controlled environment chamber showed that, when inoculation was carried out with diluted suspensions (1/10), nodulation time was reduced from 10 to 4 days, while the strains retained their symbiotic properties.

Aerobiosis↗
PubMedDate not supplied

[Rennet production by Rhizomucor miehei NRRL 3169].

The production of rennet was studied, using different strains of the fungus Rhizomucor miehei. The selection and preservation of strains, type of growth, media design and operation conditions were evaluated. The experiments were carried out in Erlenmeyer flasks in rotary shaker at 250 rpm and 2.5 eccentricity, and in mechanically stirred fermentors of the New Brunswick type, at 30 degrees C. In the studies concerning strain selection, the best strain was Rhizomucor miehei NRRL 3169. The major titles of enzyme were obtained in batch process at 168 h, with 884 SU/ml, whereas in mechanically stirred fermentors the best value was 1160 SU/ml. These values were far more superior to former ones published by various experts.

Chymosin↗
PubMedDate not supplied

[Production of soy bean inoculants. Behavior of supports based on peat from Tierra del Fuego sterilized by vapor and ethylene oxide].

The survival of Rhizobium japonicum was studied in neutralized and sterilized peats from Ushuaia and Rio Grande. The carriers were sterilized by ethylene oxide and by autoclaving. Similar counts for Rhizobium (5 x 10(8) cel/g) were obtained in peat-cultures sterilized by both methods, after eight months. A good nodulation and nitrogen fixation capacity was observed with inoculated soybean plants. Using the strain Rhizobium japonicum E-45, no appreciable difference in symbiotic effectiveness was found between the inoculants prepared with the two peats.

Argentina↗
PubMedDate not supplied

[Production of inoculates for leguminous plants. Production of cellular suspensions of Rhizobium (Lotus group)].

The influence of culture medium composition and operative conditions on the cellular growth of Rhizobium sp (group Lotus) strain is studied. As much as 1 x 10(9) cell/ml were obtained in 16 hours using sucrose in the medium as carbon source. The best growth rate was obtained (mu = O,22 h-1) when the experiments were performed at 400 r.p.m. and one volume of air/volume of medium x minute (OAR = 793,0 ml of oxygen/1 h).

Cells, Cultured↗
PubMedDate not supplied

[Production on alkaline protease by Bacillus subtilis NRRL 3411].

The aim of this work was to study the influence of medium composition and the effect of the operative conditions on alkaline protease production. Several nitrogen sources (in amount of 10 g/l) were tested and compared with bacto peptone Difco: Casein was the best. The addition of "Tween 80" 0,5% resulted in a marked increase in yields of the alkaline protease. The maximum alkaline protease production (3.342.290 UAPAM/g) was achieved using the following medium: Lactose 20 g/l; casein 10 g/l; NaCl 1,5 g/l; MgSO4.7H2O 0,15 g/l; CaCl2.2H2O 0,06 g/l; MnCl2.4H2O 0,01 g/l; "Tween 80" 5,0 g/l; EDTA 1,5 X 10(-4)M; KH2PO4 1,5 g/l; K2H PO4 1,5 g/l; Na2SO4 1,5 g/l. It was found that a volumetric relation of 0,1 ml, vol. of medium/vol. of flask at 25 degrees C of temperature was the best process condition.

Bacillus subtilis↗
PubMedDate not supplied

[Xanthan production by Xanthomonas campestris B-1459].

The production of xantano from Xanthomonas campestris B-1459 was analyzed. The experiments were performed in shaked flasks at 250 rpm and 2.5 cm eccentricity. Using a base modified medium it was possible to achieve xantano concentration of 35 g/l in 72 h of process. The modified medium contained glucose as carbon source, and yeast extract, meat peptone, malt extract and amaranth meal as growth factors and nitrogen sources, in a KH2PO4/K2HPO4 buffer.

Aerobiosis↗
PubMedDate not supplied

[Alkaline protease production].

The influence of culture medium composition on alkaline protease production was studies. Various carbon sources such as glycerol, glucose, lactose and starch were tested. Different concentrations of lactose and bactopeptone have been tested. The optimum medium composition was found to be: (g/l) lactose 20.0; bactopeptne Difco 10.0; NaCl 1.5;mgSO47.H20 0.15; CaCl2 0.06; K2HPO4 1.5; KH2PO4 1.5; Na2SO4 1.5; MnCL2.4H2O 0.01. A cell concentration of c.a 9.5 g/l has been obtained after 30 hours. The maximun alkaline protease production (5,000 uAPAM/ml) was attained after 60 hours. The trials were carried on rotary shaker in 1 liter erlenmeyer flasks containing 250 ml of medium.

Bacillus subtilis↗
PubMedDate not supplied

[Use of cheese whey for growing the Bradyrhizobium japonicum E-109 strain].

The growth of Bradyrhizobium japonicum E-109 using cheese whey as carbon source was studied. The cheese whey was previously hydrolyzed by acid or enzymatic treatment with purified beta galactosidase or a crude extract from Kluyveromyces fragilis. The results obtained demonstrated that the use of the modified enzymatic hydrolyzed whey as carbon source allowed the growth of B. japonicum E-109 reaching a concentration of approximately 10(10) viable cells/ml. These results are considered of industrial value because the poluent power whey is greatly reduced.

Animals↗