PARTIAL PURIFICATION AND CHARACTERIZATION OF BACTERIOCIN-LIKE PEPTIDE PRODUCED BY STAPHYLOCOCCUS XYLOSUS

The extensive use of antibiotics leads to an increasing number of antibiotic-resistant pathogenic microorganisms. The development of new antimicrobials is needed for clinical, veterinary, and food applications. Bacteriocins are small peptides with antimicrobial activity ribosomally synthesized by bacteria and could be applied as an alternative to classical antibiotics. In this study, the bacteriocin-like (BLIS) peptide, produced by Staphylococcus xylosus was partially purified and main characteristics (pH, thermal stability, resistance to some protease enzymes and molecular weight) were evaluated. Ammonium sulfate precipitation, acetone extraction and ion-exchange chromatography methods were applied for purification of bacteriocin. The activity of bacteriocin was detected using a well diffusion assay method and the amount of protein concentration was estimated by Lowry method. Molecular weight (~ 6 kDa) of purified bacteriocin was determined by sodium dodecyl sulphate polyacrilamide gel electrophoresis (SDS PAGE) method. The highest purification yield (80 %) was obtained using ion-exange chromatography and SP-sepharose as sorbent. The purified bacteriocin remained stable at pH values between 2.0 and 12.0 for 4 h. No decrease in antibacterial activity was estimated after 30 min at 121º C temperature. The purified bacteriocin was resistant to papain, pepsin and trypsin action. The BLIS inhibits a growth of Listeria monocytogenes (93 ± 3.0 %), Bacillus subtilis (85 ± 4.0 %), Pediococcus pentosaceus (79 ± 4.0 %), Staphylococcus aureus (51 ± 5.0 %) and Propionibacterium acnes (70 ± 5 %) up to 24 hours. Such bacteriocin preparation could be applied as antimicrobial agent in medical and food industry

Effects of Temperature, Substrate Concentration and pH on the Polycyclic Aromatic Hydrocarbon Pyrene Biodegradation by Arthrobacter sp. NJ5 Strain

Polycyclic aromatic hydrocarbons (PAHs) are widely distributed in the environment and may persist for extended periods of time. PAHs are one of the most important classes of persistent organic contaminants. High molecular weight (HMW) PAHs (compounds containing four or more fused benzene rings) are generally recalcitrant to microbial attack. Until recently, only a few genera of bacteria have been isolated with the ability to utilize four-ring PAHs as sole carbon and energy sources. Because of the toxic, mutagenic, and carcinogenic characteristics of some, PAHs have been studied extensively by many scientists around the word. This paper presents research results, where 10 microbial strains belonging to genus Arthrobacter sp. and obtained from culture collection of JSC "Biocentras"were tested for the best biodegradation of HMW PAH pyrene. Pyrene degradation experiments were conducted in liquid mineral medium. Pyrene concentration was 0. 2 mg/mL at the beginning of degradation experiments. After 72 h incubation with ten Arthrobacter sp. strains, gas chromatography analysis revealed that highest pyrene degradation (19%) was reached by Arthrobacter sp. NJ5 strain. The effect of medium pH, pyrene concentration and temperature on the intensity of the degradation by the most active strain Arthrobacter NJ5 was investigated

8-Meth­oxy-4-(4-methoxy­phen­yl)quinoline

In the title compound, C17H15NO2, the dihedral angle between the quinoline and benzene ring systems is 62.17 (1)°. In the crystal, zigzag chains propagating in c are linked by C—H⋯O hydrogen bonds, and weak C—H⋯π inter­actions link the chains

Vocational education and training curriculum: developmental assumptions and perspectives

Žinių visuomenėje ūkio plėtrą ir konkurencingumą kuo toliau, tuo daugiau lems žmogiškieji ištekliai, jų kompetencija, gebėjimas sparčiai keistis, greitai įsisavinti naujausias technologijas. Parengti žmones šiai kaitai ir sudaryti atsinaujinimo sąlygas - švietimo sistemos ir jos profesinio rengimo grandies užduotis. [...].In the future, the development of economy and its competitiveness in the knowledge society will be even more determined by human resources, human competence, and ability to change rapidly and acquire the latest technologies. Educational system and its branch vocational education and training are confronted with the challenge to train people for this change and create conditions for renewal. [...]

Kokybės duomenų įrašų valdymas

Quality records represent the information that most organizations use for management purposes. While almost any stored information can be considered a record, usually only those records requested by a particular quality management standard, or otherwise desirable for organization, are of interest. Enormous research has been done over years searching for methods of establishing the set of records desirable for an organization. Less attention has been paid to the fact that in practice a gap between desirable and actually managed records may exist. One of the factors influencing this gap may be differences between organizational culture and formal working procedures. In this paper a research is made, highlighting this point by examining record management practices in a real world company. Based on that research, an attempt is made to propose requirements for records management in order to better adhere to positive aspects of organizational culture rather than trying to change it by introducing more controls

Vocational education and training curriculum : developmental assumptions and perspectives

Žinių visuomenėje ūkio plėtrą ir konkurencingumą kuo toliau, tuo daugiau lems žmogiškieji ištekliai, jų kompetencija, gebėjimas sparčiai keistis, greitai įsisavinti naujausias technologijas. Parengti žmones šiai kaitai ir sudaryti atsinaujinimo sąlygas - švietimo sistemos ir jos profesinio rengimo grandies užduotis. [...].In the future, the development of economy and its competitiveness in the knowledge society will be even more determined by human resources, human competence, and ability to change rapidly and acquire the latest technologies. Educational system and its branch vocational education and training are confronted with the challenge to train people for this change and create conditions for renewal. [...]