Antibiofilm Effects of Heated Scallop Shell Powder on Campylobacter jejuni Biofilms

Methods to reuse large numbers of scallop shells from the harvesting regions of Japan are being explored. The major component of scallop shells is calcium carbonate (CaCO3), which forms the powerful bactericidal agent, calcium oxide (CaO), when heated. Heated scallop shell powder (HSSP) exhibits strong and broad-spectrum antimicrobial activity against bacteria, fungi, and viruses. This study investigated the antibiofilm activity of HSSP against the biofilms of Campylobacter jejuni, which is the predominant species in campylobacteriosis. Biofilm samples of C. jejuni were prepared on 0.45 µm filter paper under microaerobic conditions. The HSSP treatment inactivated and eradicated C. jejuni biofilms. The resistance of C. jejuni biofilms to HSSP was significantly higher than that of the floating cells. Moreover, the antibiofilm activity of the HSSP treatment against C. jejuni biofilms was higher than that of NaOH treatment at the same pH. These results indicated that HSSP treatment is an effective method for controlling C. jejuni biofilms.

Efficiency of disinfection of hatching eggs of chickens with «Bicin» bactericidal agent

This paper presents the results of the study of the use of aerosol disinfection of hatching eggs of the parent herd of hens of the cross «Cobb» with the domestic drug «Bicin». It was found that the most effective solution is 3% disinfectant. Aerosol treatment of hatching eggs according to the scheme: in the egg-laying, before laying in the incubator and when transferring to the hatch contributes to an increase in the hatchability of eggs from 3,6 to 8,2%.

Comparative Antimicrobial Activities of Alchornea cordifolia Leaf Crude Extracts and Cephalosporin Antibiotics on Some Pathogenic Clinical Isolates

Comparative antimicrobial activities of the aqueous and ethanol leaf extracts of Alchornea cordifolia and some Cephalosporin antibiotics of different generations available in Uy, LGA of Akwa Ibom state of Nigeria were evaluated using macro dilution assay to determine the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the plant aqueouse and ethanol leaf extracts and of the Cephalosporin antibiotics against some pathogenic Gram positive and Gram negative organisms. Results: The extraction yielded 59.9g for aqueouse leaf extract (ALE) and 74.10 g of the ethanol leaf extract. The MIC of the leaf extracts ranging from (1.953 mg/mL - 15.625 mg/ mL) and MBC ranging from (3.906 mg/mL – 62.50 mg/mL). The cephalosporin antibiotics; Ceftriaxone (Chupet®) MIC ranging from (0.0078-0.25 mg/mL), MBC (0.0312 mg/mL – 0.25 mg/mL), Cephalexin (Sporidex®) MIC ranging from (0.009766 mg/ mL - 0.625 mg/ mL), MBC (0.01953 mg/ mL -2.50 mg/ mL) and Cefuroxime with MIC ranging from (0.0078 mg/mL-0.25 mg/mL) and MBC (1.25 mg/mL - 2.5 mg/mL). Antimicrobial substances are considered as bactericidal agent when the ratio MBC/MIC ≤ 4 and bacteriostatic when the ratio MBC/MIC is > 4. The antimicrobial activities evaluated increased in the following order of potency; A. cordifolia leaf extracts > Ceftriaxone > Cefalexin > Cefuroxime considering the values of MBC/MIC. Keywords: Antimicrobial activities, bacteriostatic, bactericidal, cephalosporin, comparative.

Synthesis of Levofloxacin Derivatives with some Amines and their Complexes with Copper(II) Salts and Evaluation of their Biological Activity

Levofloxacin belongs to the fluoroquinolone family; it is a potent broad-spectrum bactericidal agent. The pharmacophore required for significant antibacterial activity is the C-3 carboxylic acid group and the 4-pyridine ring with the C-4 carbonyl group, into which binding to the DNA bases occur. In this work, we tried to show that by masking the carboxyl group through amide formation using certain amines to form levofloxacin carboxamides, an interesting activity is kept. Levofloxacin carboxamides on the C-3 group were prepared, followed by the formation of their copper complexes. The target compounds were characterized by FT-IR, elemental analysis. The antimicrobial activity of the target compounds was evaluated and showed satisfactory results compared with levofloxacin. This has indicated that the presence of the carbonyl of C-3 carboxyl moiety is not essential, as levofloxacin carboxamides showed interesting copper complexes indicating that they retain the activity of levofloxacin, since its activity depends on binding to DNA gyrase via magnesium binding.

A new water-soluble bactericidal agent for the treatment of polymicrobial infections

Grapefruit and lemon pectin obtained from the respective waste citrus peels via hydrodynamic cavitation in water only are powerful, broad-scope antimicrobial alternatives to antibiotics against Gram-negative and -positive pathogens. Dubbed IntegroPectin, these pectic polymers functionalized with citrus flavonoids and terpenes show superior antimicrobial activity when compared to commercial citrus pectin. Similarly to commercial pectin, lemon IntegroPectin determined ca. 3 log reduction of Staphylococcus aureus cells, while an enhanced activity of commercial citrus pectin was detected in the case of Pseudomonas aeruginosa cells with a minimal bactericidal concentration (MBC) of 15 mg mL-1. Although grapefruit and lemon IntegroPectin share equal MBC in the case of P. aeruginosa cells, grapefruit IntegroPectin shows boosted activity upon exposure of S. aureus cells with a 40 mg mL-1 biopolymer concentration being sufficient to achieve complete killing of the bacterial cells. Insight on the mechanism of action of these biocompatible antimicrobials and their effect on bacterial cells, at the morphological level, were obtained indirectly through Fourier Transform Infrared spectroscopy and directly through scanning electron microscopy. In the era of antimicrobial resistance, these results are of great societal and sanitary relevance as they open new avenues to develop innovative antimicrobials for the treatment of polymicrobial infections unlikely to develop drug resistance.