Antibacterial activity of methylated egg white proteins against pathogenic G+ and G− bacteria matching antibiotics

Abstract

Native egg white protein with high level of acidic amino acid residues (pI = 4.8) and hydrophilic nature was transformed into its methylated derivative (MEW), acquiring rather hydrophobic and basic character (pI = 8). The MIC of MEW against ten studied bacteria (G+ and G−) ranged between 0.5 and 1 μg/disc matching or excelling the comparative values of some known specific antibiotics (ranging from 1 to 7.5 μg/disc). Combinations of MEW (1 MIC) and different ready-made disc concentrations of antibiotics indicated either nil, antagonistic or synergistic antimicrobial effect. Replacing the antibiotic Ciprofloxacin by gradual levels of MEW (20–100 %) proportionally increased the potentiality to induce bigger sized inhibition zones. MEW (1 MIC) could inhibit the growth of 6 G+ and 4 G− pathogenic bacteria in their liquid broth media during 24 h at 37 °C, indicating its broad and wide specificity. TEM examination indicated the susceptibility of the two types of bacteria (G+ and G−) to the antimicrobial action of MEW as manifested in different signs of cellular deformations, confirming its broad specificity and its mode of action was rather targeting the cell wall and cell membrane.

Inhibition of Staphylococcus aureus LC 554891 by Moringa oleifera Seed Extract either Singly or in Combination with Antibiotics

“…Since S. aureus strain is a pathogenic bacterium, it was of interest to concentrate in this investigation on this pathogen rather than total staphylococci bacteria. The examined food samples showed themselves to be polluted with S. aureus bacterium (18% of tested foods), and this was interesting and showed that there is a need to continue to research annually to make updates about the microbial pollution of foods in Egypt to give certain attention to be careful with foods [ 9 , 17 , 18 , 19 , 20 , 21 , 22 ].…”

“…It was aseptically collected in 100 mL screw capped bottles, transported to the laboratory. HB dilutions were prepared immediately prior their testing by diluting native honey to the required concentrations (10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% v / v ) [ 10 , 21 ]. These dilutions were made using sterile distilled water.…”

“…The controls were filter paper discs soaked in sterile distilled water. Samples and controls were incubated at 37 °C for 24–48 h. IZDs were measured after subtracting the diameter of the paper disc [ 17 , 21 , 64 ].…”

Identification and Testing of Antidermatophytic Oxaborole-6-Benzene Sulphonamide Derivative (OXBS) from Streptomyces atrovirens KM192347 Isolated from Soil

“…Rats weighting 125 ± 10 g were housed in wire cages at room temperature (25 ± 5 • C) (five animals/cage). Animals were given food and water regularly and experienced 12 h light/dark cycles throughout the experimental period by oral route according to previous study in this respect [30,[71][72][73]. Afteracclimatization, ratsweredividedintofourgroups (five rats for each).…”

Detection, Purification and Elucidation of Chemical Structure and Antiproliferative Activity of Taxol Produced by Penicillium chrysogenum

“…Natural agents have recently shown a promising potential to be used as therapy for either treatment of cancer or inhibition of multidrug pathogenic bacteria [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. They also possess an attractive property in that they are safe agents.…”