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Acta Alimentaria
Authors:
J. A. Grahovac
,
Z. Z. Rončević
,
I. Ž. Tadijan
,
A. I. Jokić
, and
J. M. Dodić

Bacillus subtilis is one of the most important producers of diverse antimicrobial compounds. This bacterium grows and produces antibiotics on different substrates. The increase of the antibiotics yield can be achieved by changing the conditions of cultivation and the composition of the culture media. In this study, response surface methodology was used for optimization of glycerol, sodium nitrite, and phosphate content in media for production of antibiotics effective against Staphylococcus aureus. As biosynthesis strain Bacillus subtilis ATCC 6633 was used. The developed model predicts that the maximum inhibition zone radius (38.08 mm) against Staphylococcus aureus and minimal amount of residual nutrients (glycerol 1.75 g l−1, nitrogen 0.21 g l−1, phosphorus 0.18 g l−1) are achieved, when the initial content of glycerol, sodium nitrite, and phosphate are 49.99 g l−1, 1.00 g l−1, and 5.00 g l−1, respectively.

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The surplus of waste glycerol, by-product of the biodiesel production process, is available at the global market. Some species of the genera Streptomyces have the ability to assimilate glycerol and convert it into valuable metabolic products. In the present study, the ability of Streptomyces hygroscopicus to assimilate waste glycerol and convert it into metabolic compounds with antifungal activity against four phytopathogenic fungi obtained from apple fruit samples expressing rot symptoms, was investigated. Production of antifungal metabolites by S. hygroscopicus was carried out in 3 l stirred tank bioreactor through 7 days. Fermentation was carried out at 27 °C with aeration rate of 1.5 vvm and agitation rate of 100 r.p.m. The aim of this work was to analyse bioprocess parameters and to determine at which stage of bioprocess the production of antifungal metabolites occurs. Activity of the cultivation liquid on two isolates of Alternaria alternata and two isolates of Fusarium avenaceum were determined every 12 h using in vitro well diffusion method. It was found that the maximum production of antifungal metabolites occurred at 108 hour of cultivation. Formed inhibition zones have shown that the produced antifungal metabolites have high efficacy on tested phytopathogenic fungi (inhibition zone diameter higher than 35 mm for all test organisms).

Open access
Acta Alimentaria
Authors:
D. Šoronja Simović
,
N. Filipović
,
Z. Šereš
,
J. Gyura
,
A. Jokić
, and
B. Pajin

Research on the effects of additives produced from sugar beet is aimed at satisfying the daily intake of dietary fibre in the range of 25–35 g. Bakery products are usually consumed several times a day and this offers the possibility of incorporating dietary fibres from sugar beet. The addition of this additive to white flour can eliminate the negative effect of phytic acid, present in whole-grain cereal products, which inhibits the mineral intake. In the aim to decrease and eliminate adverse effects of sugar beet fibres on dough rheology and bread quality, optimal quantities of shortening and milk powder to the recipes were tested in order to counter addition of balance such effects. The influence of shortening and milk powder on characteristics of dough enriched with fibres (proving time and dough level) and parameters of bread quality (volume and crumb quality) was traced in two groups of samples: first without and second with 5% of added gluten. Applying regression analysis on measured parameters a mathematical model was defined. Based on presented data and regression analysis concerning samples with and without gluten, it can be stated that fibres enriched bread of the best quality can be made with gluten, shortening and milk powder at the level of 5%, 5% and 2%, respectively.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
M. Krivopustov
,
A. Pavliouk
,
A. Kovalenko
,
I. Mariin
,
A. Elishev
,
J. Adam
,
A. Kovalik
,
Yu. Batusov
,
V. Kalinnikov
,
V. Brudanin
,
P. Chaloun
,
V. Tsoupko-Sitnikov
,
A. Solnyshkin
,
V. Stegailov
,
Sh. Gerbish
,
O. Svoboda
,
Z. Dubnicka
,
M. Kala
,
M. Kloc
,
A. Krasa
,
A. Kugler
,
M. Majerle
,
V. Wagner
,
R. Brandt
,
W. Westmeier
,
H. Robotham
,
K. Siemon
,
M. Bielewicz
,
S. Kilim
,
M. Szuta
,
E. Strugalska-Gola
,
A. Wojeciechowski
,
S. Hashemi-Nezhad
,
M. Manolopoulou
,
M. Fragopolou
,
S. Stoulos
,
M. Zamani-Valasiadou
,
S. Jokic
,
K. Katovsky
,
O. Schastny
,
I. Zhuk
,
A. Potapenko
,
A. Safronova
,
Zh. Lukashevich
,
V. Voronko
,
V. Sotnikov
,
V. Sidorenko
,
W. Ensinger
,
H. Severin
,
S. Batsev
,
L. Kostov
,
Kh. Protokhristov
,
Ch. Stoyanov
,
O. Yordanov
,
P. Zhivkov
,
A. Kumar
,
M. Sharma
,
A. Khilmanovich
,
B. Marcinkevich
,
S. Korneev
,
Ts. Damdinsuren
,
Ts. Togoo
, and
H. Kumawat

Abstract  

An extended U/Pb-assembly was irradiated with an extracted beam of 2.52 GeV deuterons from the Nuclotron accelerator of the Laboratory of High Energies within the JINR in Dubna, Russia. The lay-out of this experiment and first results are reported. The Pb-target (diameter 8.4 cm, length 45.6 cm) is surrounded by a natU-blanket (206.4 kg) and used for transmutation studies of hermetically sealed radioactive samples of 129I, 237Np, 238Pu and 239Pu. Estimates of transmutation rates were obtained as result of measurements of gamma-activities of the samples. Information about the spatial and energy distribution of neutrons in the volume of the lead target and the uranium blanket was obtained with sets of activation threshold detectors (Al, Y and Au) and solid state nuclear track detectors (SSNTD). An electronic 3He neutron detector was tested on-line. A comparison of experimental data with theoretical model calculations using the MCNPX program was performed yielding satisfactory results.

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