The present work was aimed to evaluate oleo-gum resins aqueous, methanol and chloroform extracts of Commiphora myrrha for antimicrobial activity against four types of bacteria and twelve species and strains of fungi. All of the oleo-gum resin extracts irrespective of their types inhibited the growth of all microbes to varying degrees. Aqueous extract showed the least antibacterial and antifungal activity against all of the pathogens used especially with regard to gram positive bacteria Staphylococcus aureus (11 mm) and Escherichia coli (11 mm) in concentration of 100 mg mLG 1 as compared to methanol or chloroform. Less or no activity was observed against Trichophyton concentricum (7.01 mm) and 4.01 mm inhibition zone for Candida rugosa in the same concentration used. The oleo-gum resins methanol extracts in different concentrations were significantly inhibitory to the growth of the different tested fungal dermatophytes. Reduction in mycelial weight of fungi was directly correlated with concentration of extract. The concentration of 200 mg mLG 1 of myrrha was the most inhibitory against Epidermophyton floccosum with 2 g mycelial fresh weight while the less inhibition in the growth was obtained in Candida albicans and it was 6.61 g in the same extract concentration. The other used fungal or bacterial groups showed varying degrees of activity pending on the type of extract used. The Minimum Inhibitory Concentration (MIC) values of methanol and aqueous extracts of oleo-gum resins of myrrh showed that the highest values were obtained in methanol extract for Trichophyton concentricum and lowest MIC values for the same extract for the bacterium Staphylococcus aureus. In the aqueous extract of myrrha the highest and lowest MIC values were found for Bacillus subtilis and Pseudomonas aeruginosa. Phytochemical analyses showed the presence of Sesquiterpenes (Isoprenoids i.e., Terpenoids) and Furanosesquiterpenes as major constituents of the oleo-gum resins of the plant. These results confirm the antibacterial and antifungal activity of gum resins and support the traditional use of the myrrh in therapy of bacterial infections.

Enteropathogenic Escherichia coli (EPEC) is a leading cause of diarrhoeagenic diseases in humans and cattle worldwide. The emergence of multidrug-resistant (MDR) EPEC from cattle sources is a public health concern. A total of 240 samples (75 diarrhoeic calves, 150 milk samples, and 15 workers) were examined for prevalence of EPEC in three dairy farms in Egypt. Antimicrobial resistance (AMR) traits were determined by antibiogram and polymerase chain reaction (PCR) detection of β-lactamase-encoding genes, plasmid-mediated quinolone resistance genes, and carbapenemase-encoding genes. The genetic relatedness of the isolates was assessed using repetitive extragenic palindromic sequence-based PCR (REP-PCR). EPEC isolates were detected in 22.7% (17/75) of diarrhoeic calves, 5.3% (8/150) of milk samples, and 20% (3/15) of worker samples. The detected serovars were O26 (5%), O111 (3.3%), O124 (1.6%), O126 (0.8%), and O55 (0.8%). AMR-EPEC (harbouring any AMR gene) was detected in 9.2% of samples. Among isolates, blaTEM was the most detected gene (39.3%), followed by blaSHV (32.1%) and blaCTX-M-1 (25%). The qnrA, qnrB, and qnrS genes were detected in 21.4%, 10.7%, and 7.1% of isolates, respectively. The blaVIM gene was detected in 14.3% of isolates. All EPEC (100%) isolates were MDR. High resistance rates were reported for ampicillin (100%), tetracycline (89.3%), cefazolin (71%), and ciprofloxacin (64.3%). Three O26 isolates and two O111 isolates showed the highest multiple-antibiotic resistance (MAR) indices (0.85–0.92); these isolates harboured blaSHV-12 and blaCTX-M-15 genes, respectively. REP-PCR genotyping showed high genetic diversity of EPEC, although isolates belonging to the same serotype or farm were clustered together. Two worker isolates (O111 and O26) showed high genetic similarity (80–95%) with diarrhoeic calf isolates of matched serotypes/farms. This may highlight potential inter-species transmission within the farm. This study highlights the potential high risk of cattle (especially diarrhoeic calves) as disseminators of MDR-EPEC and/or their AMR genes in the study area. Prohibition of non-prescribed use of antibiotics in dairy farms in Egypt is strongly warranted.

The Pipper nigram (P. nigram) leaf extract was used for the biosynthesis of copper oxide nanoparticles (CuO NPs) and the successful formation of the resultant product was confirmed through several physicochemical techniques. The chemical structure and the elemental composition were analysed through Fourier transform infrared (FTIR) and energy dispersive X-ray (EDX) spectroscopies, respectively. The crystalline structure and crystallite size were investigated through an X-ray diffractometer (XRD) and a monoclinic crystallite with a size of 40.68 nm was reported. Even-distributed particles with an average particle size of 49.75 nm were seen in the scanning electron micrograph (SEM), whereas the thermal stability was checked during the thermogravimetric analysis (TGA). The ultra-violet and visible (UV-Visible) spectroscopy was operated to study the light absorbance phenomena and to determine the band gap energy from the absorption edge, which was found to be 1.47 eV. The CuO NPs were used as antibacterial agents against gram-negative bacteria (GNB) and gram-positive bacteria (GPB), and greater inhibition zones were seen against the former one. The antioxidant test was also carried out against 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radicals and the antioxidant potential of CuO NPs was found to be higher than ascorbic acid.

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Centaurea parviflora (C. parviflora), belonging to the family Asteraceae, is an Algerian medicinal plant used in folk medicine to treat different diseases related to hyperglycemic and inflammatory disorders, as well as in food. The present study aimed to assess the total phenolic content, in vitro antioxidant and antimicrobial activity and phytochemical profile of the extracts of C. parviflora. The extraction of phenolic compounds from aerial parts was conducted using solvents of increasing polarity starting from methanol, resulting in crude extract (CE), to chloroform extract (CHE), ethyl acetate extract (EAE) and butanol extract (BUE). The total phenolic, flavonoid and flavonol contents of the extracts were determined using the Folin–Ciocalteu and AlCl3 methods, respectively. The antioxidant activity was measured with seven methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, galvinoxyl free-radical-scavenging test, 2,2′-Azino-Bis(3-Ethylbenzothiazoline-6-Sulfonic Acid) (ABTS) assay, cupric reducing antioxidant capacity (CUPRAC), reducing power, Fe+2-phenanthroline reduction assay and superoxide-scavenging test. The disc-diffusion method aimed at testing the sensitivity of bacterial strains toward our extracts. A qualitative analysis with thin-layer chromatography of the methanolic extract was performed. Moreover, HPLC-DAD-MS was used to establish the phytochemical profile of the BUE. The BUE was found to contain high amounts of total phenolics (175.27 ± 2.79 µg GAE/mg E), flavonoids (59.89 ± 0.91 µg QE/mg E) and flavonols (47.30 ± 0.51 µg RE/mg E). Using TLC, different components such as flavonoids and polyphenols were noted. The highest radical-scavenging ability was recorded for the BUE against DPPH (IC50 = 59.38 ± 0.72 µg/mL), galvinoxyl (IC50 = 36.25 ± 0.42 µg/mL), ABTS (IC50 = 49.52 ± 1.54 µg/mL) and superoxide (IC50 = 13.61 ± 0.38 µg/mL). The BUE had the best reducing power according to the CUPRAC (A0.5 = 71.80 ± 1.22 μg/mL), phenanthroline test (A0.5 = 20.29 ± 1.16 μg/mL) and FRAP (A0.5 = 119.17 ± 0.29 μg/mL). The LC-MS analysis of BUE allowed us to identify eight compounds including six phenolic acids and two flavonoids: quinic acid, five chlorogenic acid derivatives, rutin and quercetin 3-o-glucoside. This preliminary investigation revealed that the extracts of C. parviflora have a good biopharmaceutical activity. The BUE possesses an interesting potential for pharmaceutical/nutraceutical applications.