Monitoring and bioremediation of organochlorine pesticides in surface water with Enterobacter asburiae

Aim of study: One of the safest techniques regarding the remediation of contaminated water is biological remediation. This study aimed to: (i) monitoring of a collection of organochlorine pesticides (OCPs) in three agricultural drainages (Nashart, no. 9, and El-shoka), located in Kafr El-Sheikh governorate, Egypt; and ii) investigate the biodegradation potential of different bacterial isolates regarding organochlorine pesticides.Material and methods: Analysis of OCPs was carried out by gas chromatography, Enrichment cultures were used for isolation of the bacterial strains capable of OCPs biodegradation and the most efficient isolate was identified based on morphological, biochemical ad molecular characteristics.Main results: The determination of OCPs in water samples by gas chromatography showed varying values of OCPs ranging from 0.0 mg/L (below detection limit) to 0.0385 mg/L. A total of four morphologically different bacterial isolates were obtained, which showed a remarkable capability of OCPs biodegradation detected in mineral salt medium containing 17 OCPs active ingredients by two approaches including the analysis of the OCP residues at the end of the incubation period and measuring the bacterial growth in terms of total viable count and optical density. The bacterial isolate N2 showed the highest degradation capability when the screening process was carried out to select the most efficient isolates, which was identified according to the morphological, biochemical and molecular characterization as Enterobacter asburiae.Research highlights: The biodegradation of OCPs using E. asburiae was proved to be a promising approach for the detoxification and removal of OCPs residues in aqueous systems

Emergence of microbial infections in some hospitals of Cairo, Egypt: studying their corresponding antimicrobial resistance profiles

Abstract Background Antimicrobial resistance is one of the ten major public health threats facing humanity, especially in developing countries. Identification of the pathogens responsible for different microbial infections and antimicrobial resistance patterns are important to help clinicians to choose the correct empirical drugs and provide optimal patient care. Methods During the period from November 2020 to January 2021, one hundred microbial isolates were collected randomly from different specimens from some hospitals in Cairo, Egypt. Sputum and chest specimens were from COVID-19 patients. Antimicrobial susceptibility testing was performed according to CLSI guidelines. Results Most microbial infections were more common in males and in elderly people over 45 years of age. They were caused by Gram-negative, Gram-positive bacteria, and yeast isolates that represented 69%, 15%, and 16%, respectively. Uropathogenic Escherichia coli (35%) were the most prevalent microbial isolates and showed high resistance rates towards penicillin, ampicillin, and cefixime, followed by Klebsiella spp. (13%) and Candida spp. (16%). Of all microbial isolates, Acinetobacter spp., Serratia spp., Hafnia alvei, and Klebsiella ozaenae were extremely multidrug-resistant (MDR) and have resisted all antibiotic classes used, except for glycylcycline, in varying degrees. Acinetobacter spp., Serratia spp., and Candida spp. were secondary microbial infections in COVID-19 patients, while H. alvei was a bloodstream infection isolate and K. ozaenae was recorded in most infections. Moreover, about half of Staphylococcus aureus strains were MRSA isolates and reported low rates of resistance to glycylcycline and linezolid. In comparison, Candida spp. showed high resistance rates between 77 and 100% to azole drugs and terbinafine, while no resistance rate towards nystatin was reported. Indeed, glycylcycline, linezolid, and nystatin were considered the drugs of choice for the treatment of MDR infections. Conclusion The prevalence of antimicrobial resistance in some Egyptian hospitals was high among Gram-negative, Gram-positive bacteria, and candida spp. The high resistance pattern —especially in secondary microbial infections in COVID-19 patients— to most antibiotics used is a matter of great concern, portends an inevitable catastrophe, and requires continuous monitoring to avoid the evolution of new generations

Identification of Novel Bioactive Compound Derived from Rheum officinalis against Campylobacter jejuni NCTC11168

Gastric diseases are increasing with the infection of Campylobacter jejuni. Late stages of infection lead to peptic ulcer and gastric carcinoma. C. jejuni infects people within different stages of their life, especially childhood, causing severe diarrhea; it infects around two-thirds of the world population. Due to bacterial resistance against standard antibiotic, a new strategy is needed to impede Campylobacter infections. Plants provide highly varied structures with antimicrobial use which are unlikely to be synthesized in laboratories. A special feature of higher plants is their ability to produce a great number of organic chemicals of high structural diversity, the so-called secondary metabolites. Twenty plants were screened to detect their antibacterial activities. Screening results showed that Rheum officinalis was the most efficient against C. jejuni. Fractionation pattern was obtained by column chromatography, while the purity test was done by thin-layer chromatography (TLC). The chemical composition of bioactive compound was characterized using GC-MS, nuclear magnetic resonance, and infrared analysis. Minimal inhibitory concentration (MIC) of the purified compound was 31.25 µg/ml. Cytotoxicity assay on Vero cells was evaluated to be 497 µg/ml. Furthermore, the purified bioactive compound activated human lymphocytes in vitro. The data presented here show that Rheum officinalis could potentially be used in modern applications aimed at the treatment or prevention of foodborne diseases

Antibacterial Activity of Polygonum plebejum and Euphorbia hirta Against Staphylococcus aureus (MRSA)

The agar diffusion method was used to determine the antimicrobial activities of Euphorbia hirta (EH) and Polygonum plebeium (PP) against S.aureus , B39. Ethyl acetate extract of Euphorbia hirta (EH) and Polygonum plebejum (PP),was the most effective solvent. MIC of plant extract Polygonum plebeium (PP) and Euphorbia hirta (EH) was 25mg/ ml. The antimicrobial activity of ethyl acetate extract of E. hirta (EH) and P. plebeium (PP) was more effective when incubated at 25°C for 10 min with MRSA, B39; pH 5 was more effective against MRSA, B39. Light condition for 24hr was effective against MRSA, B39; Static condition had slight effectiveness against MRSA, B39. Xylose exhibited the highest activity on MRSA, B39; no amino acids, metallic ions and vitamins were effective. Ethyl acetate extract of E. hirta (EH) was subjected to column chromatography and monitored with TLC, 5 spots were detected. Anti MRSA spots were identified as Hydroquinone and O-coumaric acid

Monitoring and bioremediation of organochlorine pesticides in surface water with Enterobacter asburiae

Aim of study: One of the safest techniques regarding the remediation of contaminated water is biological remediation. This study aimed to: (i) monitoring of a collection of organochlorine pesticides (OCPs) in three agricultural drainages (Nashart, no. 9, and El-shoka), located in Kafr El-Sheikh governorate, Egypt; and ii) investigate the biodegradation potential of different bacterial isolates regarding organochlorine pesticides.Material and methods: Analysis of OCPs was carried out by gas chromatography, Enrichment cultures were used for isolation of the bacterial strains capable of OCPs biodegradation and the most efficient isolate was identified based on morphological, biochemical ad molecular characteristics.Main results: The determination of OCPs in water samples by gas chromatography showed varying values of OCPs ranging from 0.0 mg/L (below detection limit) to 0.0385 mg/L. A total of four morphologically different bacterial isolates were obtained, which showed a remarkable capability of OCPs biodegradation detected in mineral salt medium containing 17 OCPs active ingredients by two approaches including the analysis of the OCP residues at the end of the incubation period and measuring the bacterial growth in terms of total viable count and optical density. The bacterial isolate N2 showed the highest degradation capability when the screening process was carried out to select the most efficient isolates, which was identified according to the morphological, biochemical and molecular characterization as Enterobacter asburiae.Research highlights: The biodegradation of OCPs using E. asburiae was proved to be a promising approach for the detoxification and removal of OCPs residues in aqueous systems