Bakteriler tarafından üretilen ribozomal antimikrobiyal peptidlerin bir çeşidi olan bakteriyosinler, bakterilerin %99’undan fazlası tarafından üretilmektedir. Üretici bakteri ile yakın ilişikli veya ...ilişkisiz bakteriyel suşların gelişimini inhibe eden bakteriyosinler, insan vücudu için zararsızdır. Patojen bakterilere karşı antibiyotiklere kıyasla yaygın olarak kullanılmaktadır. Ancak gıda güvenlik uyugulamaları ve gıda korumada potansiyel antimikrobiyal ajan olarak değerlendirilmektedir. Bu nedenle çalışmamızda Kilis yöresel peynirinden izole edilen laktik asit bakterilerinin bakteriyosin üretim kapasitesi araştırılmıştır. Bacillus cereus, Vankomisin-Dirençli Enterococci (VRE) ve Staphylococcus aureus’a karşı antibakteriyel aktiviteli hücre bağımlı bakteriyosin üreten 3 adet laktik asit bakterisi izole edilmiştir. Bakteriyosin süspansiyonlarının en etkili olduğu test bakterisi B. cereus’tur. Süspansiyonların test bakterileri üzerinde geniş bir pH aralığında (pH 4-12) aktivite gösterdiği belirlenmiş olup, 40ºC sıcaklıkta inhibitör etkinin stabilitesini koruduğu gözlenmiştir. Çeşitli kimyasal maddeler ile ön inkübasyonu takiben P2 süspansiyonunun diğer süspansiyonlara karşın aktivitesini sürdürdüğü belirlenmiştir.
Bacteriocins, one kind of ribosomal antimicrobial peptides, are produced by more than 99% of bacteria. Bacteriocins that are inhibited the growth of bacterial strains closely related or unrelated with producer bacteria, is harmless for human body (Yang vd., 2014). It is not extensively used against pathogenic bacteria in comparison with antibiotics. But, it is evaluated as potential antimicrobial agent in food preservation or food safety applications. In this study, the capability of bacteriocin production of lactic acid bacteria isolated from Kilis local cheese was investigated. 3 lactic acid bacteria producing bacteriocin showed antimicrobial activity against Bacillus cereus, Vancomycinresistant Enterococci (VRE) and Staphylococcus aureus were isolated. All bacteriocin suspensions were effective against B. cereus. And bacteriocin suspensions were active a wide range of pH values (pH 4-12) and stable to 40ºC heat. Following pre-incubation with the various chemical substances, the activity of P2 suspension was determined to preserve in comparison with other bacteriocin suspensions.
In this study, four new bis(amino-p-chlorophenylglyoximes), 1,2-phenylenebis(amino-p-chlorophenylglyoxime) L
1
H
2
, 1,5-naphthylenebis(amino-p-chlorophenylglyoxime) L
2
H
2
, ...3,4-tolylenebis(amino-p-chlorophenylglyoxime) L
3
H
2
, and 2,6-pyridylbis(amino-p-chlorophlenylglyoxime) L
4
H
2
have been synthesized from
anti-p
-chlorophenylchloroglyoxime and the corresponding aromatic diamines. Their polymeric complexes with Ni(II), Co(II) and Cu(II) have been prepered. The Ni(II) and Cu(II) complexes of these ligands have been found to be square-planar, while the Co(II) complexes are octahedral with water molecules as axial ligands.
1
H NMR, AAS, IR, magnetic susceptibility and elemental analytical data of the complexes and ligands are discussed.
Most of the approaches to produce flame retardant (FR) cotton-based nonwovens are not durable to washing. For some of the applications, wash durability is desired, and we are conducting research to ...develop some durable or semi-durable FR treatments in an economical way. The approach is to produce cotton nonwoven webs using a binder fiber, going through the through-air bonding process, and treating them with commercially available FR chemicals and binders. It is important to select the right combination of flame retardants and binders such that some degree of permanency can be achieved. These treated webs have been evaluated for their FR characteristics before and after washing. Both, selected FR chemical and the binder, have an effect on the durability of the produced webs. A model is being developed to understand these effects, so that it can help in selecting the best combination for optimum FR performance.
Isonitrosoacetophenone, synthesized by nitrosotion of acetophenone, has been condensed with diamines (1,4-phenylenediamine, 4,4′-diaminobiphenyl, 4,4′-diaminodiphenylmethane or ...4,4′-diaminodiphenylether) to obtain the tetradentate Schiff bases 1,4-phenyliminobis(isonitrosoacetophenone), I,I'-biphenyl-4,4′-diiminobis(isonitrosoacetophenone), 1,1′-diphenylmethane-4,4′-diiminobis(isonitroso-acetophenone) or 1,1′-diphenyloxy-4,4′-diiminobis(isonitrosoacetophenone). The polymeric Ni(II) and Cu(II) complexes of these Schiff bases are square-planar while the polymeric Co(II) complexes are octahedral with water molecules at the axial positions. The structures of the above complexes were determined by
1
H NMR and IR spectroscopy and elemental analyses.
In this work, a novel heterocyclic dioxime (2,3-hydroximino-4-phenyl-6-phenlyazo-1-thia-4,5-diazacyclohexa-5diene, H
2
L) was synthesized by reacting dithizone with cyanogen di-N-oxide. H
2
L forms ...mononuclear complexes (HL)
2
M with a metal-ligand ratio of 1-2 with M = Ni(II), Co(II) and Cu(II). Zn(II), Cd(II) and Hg(II) form with H
2
L complexes (HL)CI(H
2
O)M which have a metal-ligand ratio of 1:1 and contain a six-membered chelate ring. Structures of these compounds are proposed based on elemental analyses, U. V. -Visible, IR,
1
H NW mass spectra and magnetic susceptibility measurements.
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