Eleven yoghurt samples were collected from local markets in Baghdad to isolate Lactobacillus buchneri. Only 3 isolates of L. buchneri were found and the isolate No. 3 was the most producer of bacteriocin. Bacteriocin was adsorbed 100% onto silicic acid at pH 6.0-7.0. Below or above these pH values, adsorption was decreased, ranging between 35 and 90%. Therefore, pH 6.0 was used for the purification procedure. The purification procedure including silicic acid adsorption/desorption and cation-exchange chromatography (CEC) resulted in a 11.11 fold increase in the final specific activity of pure bacteriocin (1176.47 Au/mg) compared to the culture supernatant which was 32.64 Au/mg. The molecular weight was determined to be about 3.4 kDa. The bacteriocin lost its activity completely after treatment with proteolytic enzymes and it was resistant to non-proteolytic enzymes. The results indicated that bacteriocin at both concentrations (500 and 1000 μg/ml) possesses significant antimicrobial activity against Vibrio parahaemolyticus in contrast with control (P<0.01) and the antimicrobial activity of crude and purified bacteriocin at the concentration of 1,000 μg/ml were higher than the other concentration (500 μg/ml). The antimicrobial activity of purified bacteriocin was significantly higher than that of crude bacteriocin (P<0.01).
A new derivatives of Schiff bases connected with 5H-thiazolo[3,4-b][1,3,4]thiadiazole ring 5a-c were prepared via many reactions starting by treating 1,4-phenylene diamine 1 with chloroacetylchloride to prepared compound 2, then reaction with p-hydroxybenzaldehyde to synthesize compound 3 then, this was reacted with thioglycolic acid and thiosemicarazide to giveN,N-(1.4-phenylene)bis(2-(4-(2-amino-5Hthiazolo[4,3-b][1,3,4]thiadiazol-5-yl)phenoxy)acetamide) 4. Compound 4 was treated with different aromatic aldehydes to give a new derivatives of Schiff bases containing 5H-thiazolo[3,4-b][1,3,4]thiadiazole ring 5a-c. The synthesized compounds were characterized using FTIR spectrophotometer and 1H NMR spectroscopy and the biological activity of
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In the present paper, chitosan Schiff base has been synthesized from chitosan’s reaction with the salicyldehyde. The AuNPs was manufacture by extract of onion peels as a reducing agent. The Au NPs that have been prepared were characterized through the UV-vis spectroscopy, XRD analyses and SEM microscopy. The polymer blends of the chitosan Schiff base / PVP has been prepared through using the approach of solution casting. Chitosan Schiff base / PVP Au nano-composites was prepared. Nano composites and polymer blends have been characterized by FTIR which confirm the formation of Schiff base by revealing a new band of absorption at 1651cm-1 as a result of the (C=N) imine group. SEM, DSC and TGA confirms the thermal stability of the pr
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Endothelin-1 (ET-1) is a potent vasoconstrictor hormone that has been identified as an important factor
responsible for the development of cardiovascular dysfunctions. ET-1 exerts its vasoconstrictor activity
through two pharmacologically distinct receptors, ETA and ETB that are found in vascular smooth muscle
cells (VSMCs) and the vasodilator activity through an ETB receptor located on endothelial cells. This study
aimed to show the impact of 1µM L-arginine (LA), 100µM tetrahydrobiopterin (BH4), and their combined
effect on ET-1 activity in both lead-treated and lead-untreated rat aortic rings. This means, investigating how
endothelial dysfunction reverses the role of nitric oxide precursor and cofa
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الوصف Mixed ligand complexes of Cu (II), Co (II) and Zn (II) with 2-((4-(1-(4-chlorophenylimino) ethyl) phenylimino) methyl) phenol (L) and histidine (His) have been prepared and diagnosed by ¹H and13 C NMR, FT-IR and electronic spectral data, thermal gravimetric, molar conductance and metal analysis measurements. The ligand (L) shows a bidentate nature and the coordination occurs through N and O atoms of imine group and phenol group respectively whereas (His) behave as tridentate ligand, coordinating through the-NH2 group and carboxylate oxygen group and N atoms of imidazole ring. The analytical studies for three complexes have shown octahedral structure. The anticancer activity was screened against human cancer cell such Follicular
... Show Moreantimicrobial solutions against Coliforms, E. coli O157: H7, yeasts and molds were evaluated by agar well diffusion method. Chitosan (CH) exhibited best antimicrobial activity against the treated microorganisms at concentration of (5%) with contact time for 6hrs at refrigeration temperature (4ÚC), zones of inhibition for (GA) and (CH) for each solution alone ranging from (0 to 10 mm), chitosan solution (CH) exhibited both antibacterial and antifungal activities, Gum Arabic washing solution showed significant antibacterial activity (P < 0.05) against the microorganisms at concentration (15%), without inhibitory effect against E. coli O157:H7 at concentration (10%), in the current study the results confirmed that (15%) (w/v) of GA and 5%
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In the present paper, chitosan Schiff base has been synthesized from chitosan’s reaction with the salicyldehyde. The AuNPs was manufacture by extract of onion peels as a reducing agent. The Au NPs that have been prepared were characterized through the UV-vis spectroscopy, XRD analyses and SEM microscopy. The polymer blends of the chitosan Schiff base / PVP has been prepared through using the approach of solution casting. Chitosan Schiff base / PVP Au nano-composites was prepared. Nano composites and polymer blends have been characterized by FTIR which confirm the formation of Schiff base by revealing a new band of absorption at 1651cm-1 as a result of the (C=N) imine group. SEM, DSC and TGA confirms the thermal stability of
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This work involves synthesis and characterization of some new 1, 3, 4-thiadiazole or pyrazoline derivatives heterocyclic containing indole ring. The new 2-amino-1, 3, 4-thiadiazole derivatives [IV] and [V] a, b were synthesized by cyclization reaction of 2-methyl-1H-indole-carbothiosemicarbazide [III] in H2SO4 acid or by reaction of indole-3-acetic acid or indole-3-butanoic acid with thiosemicarbazide in the presence of phosphorous oxychloride, respectively. Amide derivatives [VI]-[VIII] were synthesized by the reaction equimolar of 2-amino-1, 3, 4-thiadiazoles and (acetyl chloride, benzoyl chloride, anisoyl chloride and heptanoyl chloride) in DMF and pyridine as accepter. The new pyrazolone derivatives [XI] a, b were synthesized from heati
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