Hikmet Katırcıoğlu

Synthesis and biological activity studies of furan derivatives

The organic compounds, 4-Ethyl-2,5,5-triphenyl-4,5-dihydrofuran-3-carbonitrile; 2,4,5-Triphenyl-5-propyl-4,5-dihydrofuran-3-carbonitrile; 4-Ethyl-5,5-diphenyl-2-thien-2-yl-4,5-dihydrofuran-3-carbonitrile; 2-(1-Benzofuran-2-yl-)-5-propyl-4,5-diphenyl-4,5-dihydrofuran-3-carbonitrile; 4-Ethyl-5,5-diphenyl-4,5-dihydro-2,2’-bifuran-3-carbonitrile, were synthesized and purified through column chromatography and preparative TLC. All compounds were characterized by IR, 1H, 13C NMR, MS, and microanalysis. The in vitro antibacterial and antifungal activities of these compounds were investigated against some bacteria and fungi. The antibacterial and antifungal activities were measured by using the disc-diffusion method against gram-positive bacteria, i.e., Staphylococcus aureus ATCC 25923, Staphylococcus enteritidis ATCC1376, Psydomamonas aeruginosa ATCC 29212, Bacillus subtilis RSKK 244, Bacillus megaterium gram-negative bacteria Escherichia coli ATCC 27853, Listeria monocytogenes ATCC 7644, and as fungus Micrococcus Luteus NRRLB was used. All compounds in this study showed activity against test bacteria. Their antibiogram tests showed better results than some known antibiotics.

Production of poly-β-hydroxybutyrate (PHB) and differentiation of putative Bacillus mutant strains by SDS-PAGE of total cell protein

In this study, the putative mutant strains of Bacillus megaterium Y6, B. subtilis K8, B. sphaericus X3 and B. firmus G2 were studied for their poly--hydroxybutyrate (PHB) production capacities. Mutations were induced by using UV light, acriflavin and 5-bromourasil. Total cell proteins were extracted from 59 strains and compared using SDS-PAGE. For each strain, percentage yield of PHB according to cell dry weight was determined in a range of 1.46-63.45%. PHB production of 8 mutant strains were found to increase in comparison with parental strains. However, no increase in PHB production of mutant strains of B. sphaericus X3 was found. It was also determined that the protein profiles of the mutant strains with high PHB yield generally differed from the protein profiles of parental strains.

Antimicrobial activity and pollen composition of honey samples collected from different provinces in Turkey

The antibacterial activity of honey samples from different sources were collected and investigated against Bacillus cereus, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 27736, Morganella morganii, Micrococcus luteus NRRL B-4375, Escherichia coli ATCC 35218, and Candida albicans. Pathogens exhibited different sensitivities towards the honey samples. The results showed that majority of the honey samples (75%) generally inhibitied the bacteria tested. The honey samples which were obtained from İzmir (samples 1 and 2) proved more effective as inhibitors against P. aeruginosa, E. coli, and S. aureus. The honey which was obtained from Muğla (sample 5) exhibited high anticandidal activity on C. albicans. A comparison of the honey samples on the basis of pollen content revealed that they were heterofloral, and samples which had highest antibacterial activity against P. aeruginosa, E. coli, and S. aureus were dominated by pollen from Chenopodiaceae/Amaranthaceae (sample 1), and Trifolium, Trigonella, Cyperaceae, Zea mays and Anthemis taxa (sample 2). The honey proved more effective on bacteria than antibiotics.

Chemical composition effects onto antimicrobial and antioxidant activities of propolis collected from different regions of Turkey

Chrysin, apigenin, flavonoids, flavanones, naringenin, ethyl oleate, 3-4-dimethoxy-cinnamic acid and 9-octadecenoic acid were the predominant components of propolis samples collected from different regions of Turkey. The extracts of P3 from Denizli-Başkarci, P5 from Denizli and P7 from Tekirdaĝ had effective antibacterial activities on Gram-negatives. Chrysin, which has antibacterial activity, was found to be high concentration. The extracts of P3, P2B from Aydin and P6 from Konya had much more effective antibacterial activities on Gram-positives. The total antioxidant activity increased with the increasing amount of extracts added to linoleic acid emulsion. All doses of propolis ethanol extract displayed antioxidant activity.

Administration of Chlorella sp. microalgae reduces endotoxemia, intestinal oxidative stress and bacterial translocation in experimental biliary obstruction

RATIONALE Endotoxemia has long been documented in obstructive jaundice, and altered intestinal barrier function is considered to be one of the important mechanisms for this phenomenon. The aim of this study was to investigate the role of different microalgae (Chlorella sp. and Spirulina sp.) extracts in intestinal barrier function and oxidative stress in experimentally jaundiced rats. METHODS A total of 60 male wistar rats were randomly divided into four groups of 15 each: I, sham operated; II, bile duct ligation (BDL); III, BDL+Chlorella sp.; IV, BDL+Spirulina sp. Rats were fed rat chow or microalgae extracts supplemented enteral diet ten days after sham operation or BDL. Main outcome measures were endotoxin concentrations in plasma, evidence of bacterial translocation (BT) in mesenteric lymph nodes (MLNs) and liver, oxidative stress, and histology. RESULTS Compared to the group I, a significant increase in contamined MLNs, liver, and spleen samples and increased endotoxemia were noted in group II (P<0.01) but were significant reduced in group III (P<0.05). There was no significant difference in BT rate between the group II and group IV (P>0.05). Moreover, Chlorella sp. administration protected in jaundiced rats against oxidative stress, as demonstrated by reduction of intestinal lipid peroxidation, increase of the antioxidant reduced glutathione (GSH), and decrease of the oxidized glutathione (GSSG). The intestinal mucosa in control rats was atrophic with significantly decreased villous density and total mucosal thickness. Chlorella sp. caused a significant reduction in villous atrophy compared with controls. CONCLUSIONS Chlorella sp. microalgae supplemented enteral diet has significant protective effects on intestinal mucosa barrier in obstructive jaundice, and reduces intestinal translocation of bacteria and endotoxin.

Effects of Cholerella sp. microalgae extract on colonic anastomosis in rats with protein–energy malnutrition

Objective Algae, which are used as supplementary nutrients in various countries, are products rich in protein, vitamins and minerals. The aim of this study was to investigate the effects of algae extracts on the healing of colonic anastomosis in malnourished rats.

Synthesis of 2,4-dihalogenofluorobenzenes and their antimicrobial and antifungal activity studies

The aim of this study was to synthesize and identify 2,4-dihalogenofluorobenzene (or trihalogenobenzene) derivatives by spectroscopic means, 1H-NMR and 19F-NMR. The 2,4-dihalofluorobenzene derivatives considered were 2,4-dichlorofluorobenzene (1), 2-bromo-4-chlorofluorobenzene (2), 2-iodo-4-chlorofluorobenzene(3), 2,5-dichlorofluorobenzene (4), 2-bromo-5-chlorofluorobenzene (5), 2-iodo-5-chlorofluorobenzene (6).The in vitro antibacterial and antifungal activities of trihalogenobenzene derivatives were studied against the bacteria Staphylococcus aureus ATCC 25923 Gram(+), Bacillus cereus ATCC 6633 Gram(+), Micrococcus flavus (clinical isolate) Gram(+), Morgenella morganii (clinical isolate) Gram(-), Escherichia coli ATCC 27853 Gram(-) and fungus Candida albicans (clinical isolate), obtained from the biology departments of the Pamukkale and Gazi Universities. The antibacterial and antifungal activities were measured by minimum inhibition concentration (MIC) method and the disc-diffusion method used to measure zone diameter against Gram-positive and Gram-negative bacteria and fungi. All these bacteria and fungi were studied against antibiotics to compare the zone diameters with the results from our treatments.