Antagonistic Potentiality of Actinomycete-Derived Extract with Anti-Biofilm, Antioxidant, and Cytotoxic Capabilities as a Natural Combating Strategy for Multidrug-Resistant ESKAPE Pathogens.

The global increase in multidrug-resistant (MDR) bacteria has inspired researchers to develop new strategies to overcome this problem. In this study, 23 morphologically different, soil-isolated actinomycete cultures were screened for their antibacterial ability against MDR isolates of ESKAPE pathogens. Among them, isolate BOGE18 exhibited a broad antibacterial spectrum, so it was selected and identified based on cultural, morphological, physiological, and biochemical characteristics. Chemotaxonomic analysis was also performed together with nucleotide sequencing of the 16S rRNA gene, which showed this strain to have identity with Streptomyces lienomycini. The ethyl acetate extract of the cell-free filtrate (CFF) of strain BOGE18 was evaluated for its antibacterial spectrum, and the minimum inhibitory concentration (MIC) ranged from 62.5 to 250 µg/ml. The recorded results from the in vitro anti-biofilm microtiter assay and confocal laser scanning microscopy (CLSM) of sub-MIC concentrations revealed a significant reduction in biofilm formation in a concentration-dependent manner. The extract also displayed significant scavenging activity, reaching 91.61 ± 4.1% and 85.06 ± 3.14% of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis( 3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), respectively. A promising cytotoxic ability against breast (MCF-7) and hepatocellular (HePG2) cancer cell lines was obtained from the extract with IC50 values of 47.15 ± 13.10 and 122.69 ± 9.12 µg/ml, respectively. Moreover, based on gas chromatography-mass spectrometry (GC-MS) analysis, nine known compounds were detected in the BOGE18 extract, suggesting their contribution to the multitude of biological activities recorded in this study. Overall, Streptomyces lienomycini BOGE18-derived extract is a good candidate for use in a natural combating strategy to prevent bacterial infection, especially by MDR pathogens.

The control of poultry salmonellosis using organic agents: an updated overview.

Salmonellosis is a severe problem that threatens the poultry sector worldwide right now. Salmonella gallinarium and Salmonella pullorum (Fowl typhoid) are the most pathogenic serovars in avian species leading to systemic infection resulting in severe economic losses in the poultry industry. Nontyphoidal serotypes of Salmonella (Paratyphoid disease) constitute a public health hazard for their involvement in food poisoning problems in addition to their zoonotic importance. Also, Salmonella species distribution is particularly extensive. They resisted environmental conditions that made it difficult to control their spread for a long time. Therefore, the current review aimed to through light on Salmonellosis in poultry with particular references to its pathogenesis, economic importance, immune response to Salmonella, Salmonella antibiotics resistance, possible methods for prevention and control of such problems using promising antibiotics alternatives including probiotics, prebiotics, symbiotics, organic acids, essential oils, cinnamaldehyde, chitosan, nanoparticles, and vaccines.