The herbal products proved to be more promising antimicrobials even though their antimicrobial activity is milder than commercially available antibiotics. Moreover, herbal drugs may act synergistically with antibiotics to kill microbes. In this study, we aimed to enhance the activity of penicillin against MRSA through combination with the active saponin fraction isolated from the Zygophyllum album plant. Three different types of metabolites (saponins, sterols, and phenolics) have been extracted from Zygophyllum album with ethanol and purified using different chromatographic techniques. The antibacterial activity of crude extract and the separated metabolites were checked against MRSA isolates, Saponin fraction (ZA-S) was only the active one followed by the crude extract. Therefore, the compounds in this fraction were identified using ultra-high-performance liquid chromatography connected to quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS) operated in positive and negative ionization modes. UHPLC/QTOF-MS revealed the presence of major six ursane-type tritepenoidal saponins (Quinovic acid, Quinovic acid 3β-O-β-D-quinovopyranoside, Zygophylloside C, Zygophylloside G, Zygophylloside K and Ursolic acid), in addition to Oleanolic acid. Interaction studies between saponin fraction and penicillin against MRSA were performed through the checkerboard method and time-kill assay. According to checkerboard results, only three combinations showed a fractional inhibitory concentration index less than 0.5 at concentrations of (62.5 + 312.5, 62.5 + 156.25, and 62.5 + 78.125 of penicillin and ZA-S, respectively). Time kill assay results showed that the highest reduction in log10 colony-forming unit (CFU)/ml of initial inoculum of MRSA after 24 h occurred by 3.7 at concentrations of 62.5 + 312.5 (µg/µg)/ml of penicillin and ZA-S, respectively. Thus, the combination between saponin fraction of Zygophyllum album and penicillin with these concentrations could be a potential agent against MRSA that can serve as possible model for new antibacterial drug.

Highlights Penicillium polonicum , an endophyte of Ginkgo biloba, is a potent Taxol producer. Taxol of P. polonicum has a strong anticancer effect against HEPG2 and MCF7. The Taxol yield by P. polonicum was increased by 4.5 folds upon optimization with response surface methodology.

No abstract

HighlightsIsolation and identification of thermo alkaliphilic actinomycetes.Obtaining of thermostable alkaline protease enzyme.Evaluation of the nematicidal activity of obtained protease.Application of thermostable alkaline protease as nemticidal agent.

Background: Carbapenem antibiotics consider the primary treatment choice for serious Pseudomonas aeruginosa infection. Hence, the evolution of carbapenem resistance mediated by acquiring genes encoding class b enzymes is of global concern. The purpose of this article research is to explore the prevalence, drug resistance profiles, and metallo-βlactamases (MβLs) production in extensively drug-resistant carbapenem-resistant P. aeruginosa (XDR-CRPA). Methods: P. aeruginosa isolates were collected and identified according to conventional methods. Antibiotic resistance patterns were determined by single disk diffusion. Minimum inhibitory concentrations (MICs) of (imipenem, meropenem, ceftazidime, piperacillin/tazobactam, levofloxacin, and gentamicin) were determined for CRPA. A subset of the isolates collection consisting of the XDR-CRPA with the highest MICs to imipenem and meropenem were selected for the phenotypic screening of carbapenemases and MβLs production capability using the modified carbapenem inactivation (mCIM) and imipenem-EDTA combined disk (MβL-CD) methods, respectively. Then, molecular analysis, including identification by the specific primer of 16S rRNA and detection of MβL genes using polymerase chain reaction (PCR) was performed to the XDR selected isolates. Results: Among 100 P. aeruginosa isolated throughout this period, 59% exhibited reduced susceptibility rates to carbapenems. A total of 20.3% and 57% of CRPA isolates were MDR and XDR, respectively. MIC values of the CRPA revealed that these isolates exhibited high MIC 50 and MIC 90 to the six selected antibiotics. The findings of the (mCIM) assay displayed identical concordance results with the MβL-CD. Molecular investigation technique assured that 10 (90.9%) and 2 (18.1%) of the 11 XDR selected isolates are positive for bla NDM-1 and bla VIM-1 genes, respectively. Polymyxin B and colistin followed by aztreonam were the most effective antibiotics used for curing infections caused by XDR Pseudomonas aeruginosa. Conclusion: The prevalence of high XDR-CRPA in our study is a critical problem. Our present study found that the bla NDM-1 was present at a significant frequency among the selected XDR isolates, highlighting the need for establishing strict antimicrobial policies to avoid the prompt spread of these isolates.

Taxol production by fungi is one of the promising alternative approaches, regarding to the natural and semisynthetic sources; however, the lower yield and rapid loss of Taxol productivity by fungi are the major challenges that halt their further industrial implementation. Thus, searching for fungal isolates with affordable Taxol-production stability, in addition to enhance its anticancer activity via conjugation with gold nanoparticles, is the main objectives of this study. Twenty-four endophytic fungal isolates were recovered from the barks, twigs, and leaves of jojoba plant, among these fungi, Aspergillus flavus MW485934.1 was the most potent Taxol producer (88.6 µg/l). The chemical identity of the extracted Taxol of A. flavus was verified by the TLC, HPLC, HNMR, and FTIR analyses. The yield of Taxol produced by A. flavus was optimized by the response surface methodology (RSM) using Plackett–Burman (PBD) and faced central composite designs (FCCD). The yield of Taxol by A. flavus was increased by about 3.2 folds comparing to the control cultures (from 96.5 into 302.7 µg/l). The highest Taxol yield by was obtained growing A. flavus on a modified malt extract medium (g/l) (malt extract 20.0, peptone 2.0, sucrose 20.0, soytone 2.0, cysteine 0.5, glutamine 0.5, and beef extract 1.0 adjusted to pH 6.0) and incubated at 30 °C for 16 days. From the FCCD design, the significant variables affecting Taxol production by A. flavus were cysteine, pH, and incubation time. Upon A. flavus γ-irradiation at 1.0 kGy, the Taxol yield was increased by about 1.25 fold (375.9 µg/l). To boost its anticancer activity, the purified Taxol was conjugated with gold nanoparticles (AuNPs) mediated by γ-rays irradiation (0.5 kGy), and the physicochemical properties of Taxol-AuNPs composite were evaluated by UV–Vis, DLS, XRD, and TEM analyses. The IC50 values of the native-Taxol and Taxol-AuNPs conjugates towards HEPG-2 cells were 4.06 and 2.1 µg/ml, while the IC50 values against MCF-7 were 6.07 and 3.3 µg/ml, respectively. Thus, the anticancer activity of Taxol-AuNPs composite was increased by 2 folds comparing to the native Taxol towards HEPG-2 and MCF-7 cell lines. Also, the antimicrobial activity of Taxol against the multidrug resistant bacteria was dramatically increased upon conjugation with AuNPs comparing to authentic AuNPs and Taxol, ensuring the higher solubility, targetability, and efficiency of Taxol upon AuNPs conjugation.

No abstract

The aim of this study was carried out determine the antibiotic susceptibility, heavy metals tolerance and plasmid curing of Shigella species isolating from diarrheal stool samples were collected from different hospitals in El-Dakahlia and Nile River waters, Egypt, from January 2012 to August 2014. After characterization and identification the results obtained show that 172 isolates isolated from stool samples belong to four Shigella species (Shigella sonnei 48.25 %, Shigella flexneri 29.65 %, Shigella dysenteriae 13.95 % and Shigella boydii 8.13 %) while 5 isolates isolated from Nile River water were found belong to (Shigella sonnei 40%, Shigella dysenteriae 40 % and Shigella flexneri 20 %).The antibiotics susceptibility of Shigella sp. to11 antibiotics revealed that the most potent antibiotics were found co-amoxyclav, ciprofloxacin and ceftriaxone respectively while penicillin, ampicillin, co-trimoxazole and chloramphenicol respectively give low activity. The tolerance of Shigella sp. to heavy metals, (cadmium, nickel cobalt and zinc) revealed that all isolates sensitive to 1 and 0.1M concentration. Plasmid profile analysis of ten isolates Shigella sonnei shown that this isolates having numerous plasmid ranged from 8.5 to 4.3 kb. Treat isolates with SDS 2% for 24 hours to plasmid curing after recovery subject to antibiotic sensitivity and heavy metals tolerance. In conclusion, Shigella-associated diarrhea remains relatively common in Egypt and can be used ciprofloxacin and ceftriaxone for treat Shigella sp. infection. The heavy metal tolerance of Shigella sp .associated with resistance to antibiotics ampicillin, tetracycline and chloramphenicol. Present Shigella sp. in Nile River waters indicates polluted with sewage waters and becomes sources of some epidemic diseases.