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In the present work, the rapid RP-HPLC method with UV (DAD) detection for simultaneous quantification of bioflavonoids: quercetin, apigenin, catechin, epicatechin, kaempferol, and luteolin in Brassica oleracea species samples (cauliflower, broccoli, and Brussels sprouts) was developed with the aid of LC-Simulator (ACD LabsA (R) suite) software. A series of extracts obtained with different extraction method were evaluated for antioxidant activity. The optimal conditions for separation and quantification were established after nine scouting runs entered to LC-Simulator software. The optimized separation was achieved on Hypersil GOLD aQ column with isocratic elution and mobile phase composition A:2 % acetic acid in water and B:acetonitrile in 91:9 (v/v %) ratio. The R (s) values were in the range from 2.6 to 8.00, indicating good selectivity of the method. The obtained results generally show good agreement with published data. Low detection limits (0.02-0.055 mu g/mL) were obtained with acceptable recoveries (90-109 %). Total time of analysis was less than 11 min; therefore, the proposed method represents significant improvement over existing methods. Extracts from Brassica vegetables, obtained using different extraction procedures, were studied for their radical scavenging effects. Scavenging of DPPH showed different kinetics at the beginning of the assay period and after 15 min from the initialization of reaction. Different kinetics suggested the presence of polymerized and/or less active antioxidants with different scavenging mechanisms for particular polyphenolic compounds.

The speciation of Cu2+, Ni2+ and Zn2+ ions in the presence of the fluoroquinolones (FQs) moxifloxacin, ofloxacin, levofloxacin and ciprofloxacin, in human blood plasma was studied under physiological conditions by computer simulation. The speciation was calculated using an updated model of human blood plasma including over 6,000 species with the aid of the program Hyss2009. The identity and stability of metal-FQ complexes were determined by potentiometric (310 K, 0.15 mol/L NaCl), spectrophotometric, spectrofluorimetric, ESI-MS and H-1-NMR measurements. In the case of Cu2+ ion the concentration of main low molecular weight (LMW) plasma complex (Cu(Cis) His) is very slightly influenced by all examined FQs. FQs show much higher influence on main plasma Ni2+ and Zn2+ complexes: (Ni(His)(2) and Zn(Cys) Cit, respectively. Levofloxacin exhibits the highest influence on the fraction of the main nickel complex, Ni(His)(2), even at a concentration level of 3 x 10(-5) mol/L. The same effect is seen on the main zinc complex, Zn(Cys) Cit. Calculated plasma mobilizing indexes indicate that ciprofloxacin possesses the highest mobilizing power from plasma proteins, toward copper ion, while levofloxacin is the most influential on nickel and zinc ions. The results obtained indicate that the drugs studied are safe in relation to mobilization of essential metal ions under physiological conditions. The observed effects were explained in terms of competitive equilibrium reactions between the FQs and the main LMW complexes of the metal ions.

Uvod: Probiotici se koriste vekovima kao deo humane ishrane i u poslednje vreme pridaje im se sve vise značaja. Cilj ovog rada bio je ispitivanje imunoloških aspekata konzumiranja soja Lactobacillus rhamnosus LA68. Metodologija: Soj LA68 davan je miševima oralno, gavažom četiri puta nedeljno tokom mesec dana. Korišćena je sveža prekonoćna kultura i jedna doza sastojala se od 2x109 CFU. Nakon isteka eksperimentalnog perioda izolovani su mišji splenociti i analizirani pomoću protocne citometrije. Meren je i odgovor splenocita u vidu sekrecije citokina (IFN-y, IL-6, IL-10 and IL-17) kao i proliferacija nakon stimulacije lipopolisaharidom i peptidoglikanom. Analizirani su i citokini u serumu eksperimentalnih miševa. Zdravstveno stanje životinja praćeno je merenjem težine i osnovnih biohemijskih parametara. Rezultati: Oralna aplikacija soja LA68 dovodi do značajnog smanjenja zastupljenosti CD3+, CD25+ i CD19+ celija i do povecanja CD11b+ and CD16/CD32+ ćelija u slezini eksperimentalnih miševa. Detektovana je i povećana osetljivost na stimulaciju merenjem ćelijske proliferacije i sekrecije IL-6. U serumu eksperimentalnih miševa detektovan je poviseni nivo IFN-y i smanjenje IL-10. Težina životinja i biohemijski parametri nisu se razlikovali među grupama i ulazili su u opseg normalnih vrednosti za ovu vrstu miša. Zaključak: Dobijeni rezultati ukazuju na povećanu osetljivost splenocita na stimulaciju, aktivaciju Th1 tipa imunskog odgovora i pomeranje leukocitne populacije ka monocitno/granulocitnoj populaciji. Detektovane promene mogu pomoći organizmu u odbrani protiv određenih vrsta infekcija i umanjiti simtome alergije., Introduction: Probiotic bacteria have been used in human nutrition for centuries and are attracting more attention in recent years. The aim of this study was to evaluate the effects of Lactobacillus rhamnosus LA68 on the immune system of mice. Methodology: In order to examine the immunological aspects of probiotic consumption LA68 was orally administrated via gavage to C57 BL/6 mice. Gavage was performed four times per week for the duration of one month. Fresh overnight culture was used and one dose consisted of 2x109 CFU. Upon completion mouse splenocytes were isolated and analyzed by flow cytometry. The magnitude of splenocyte proliferation upon stimulation with LPS and peptidoglycan and cytokine levels (IFN-y, IL-6, IL-10 and IL-17) were assessed. Cytokine levels in the serum were also analyzed. Mouse well being was monitored with weight measurement and basic blood biochemisty. Results: Oral application of strain LA68 leads to a significant decrease of CD3+, CD25+ and CD19+ cells, and an increase of CD11b+ and CD16/CD32+ positive cell populations in the mouse spleen. Increased sensitivity to stimulation through proliferation and IL-6 secretion was detected. Increased serum IFN-y and decreased IL-10 levels were found. Animal weight and biochemical parameters did not differ between the groups and were within the normal values for this mouse strain. Conclusion: Our results show increased responsiveness of splenocytes, activation of the Th1 type of immune response, and a shift of leukocyte populations toward monocyte/granulocyte populations. Changes detected consist of a boost in defense mechanisms against certain types of bacteria and ameliorate allergy symptoms.