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Schistosomiasis ranks second behind malaria in terms of overall morbidity and mortality. We evaluated the lethal effect of Punica granatum ellagitannins, extracted from the fruit rind, placenta and barks of the root and stem, on adult worms of Schistosoma mansoni (S. mansoni). All four ellagitannins were lethal to S. mansoni adult worms. However, while the rind ellagitannins were the most potent, placental ellagitannins were the least. Rind ellagitannins were capable of killing 40% of adult worms at a concentration of 25µg/mL after 5 days. The killing of 100% of the worms was achievable by rind ellagitannins at a concentration of 50µg/mL after 5 days. The LD50S of the rind ellagitannins after 96h and 120h were 41.25 µg/mL and 28.73 respectively. Ellagitannins-treated worms suffered from erosions, wrinkles, swellings and losses, degenerations of the surface tubercles and tegument. In addition, ellagitannins induced deformation and degradation of oral and ventral suckers and degenerations in the muscles of worms. Ellagitannins also caused a separation of coupled worms and reduction of their motility. Data obtained suggest that ellagitannins of pomegranate could be considered as a cheap candidate for the treatment of schistosomiasis.

Background and Objective The emergence of carbapenem-resistant K. pneumoniae (CRKP) continues to escalate and is alarming because of the emergence of pan drug-resistant strains. The objective of this study was to investigate the existence of 12 carbapenemase genes among CRKP clinical isolates. Methods Ninety-six Klebsiella spp. clinical isolates were collected. The isolates were identified phenotypically and genotypically. These isolates were screened for susceptibility to 24 different antibiotics. The modified Hodge test (MHT) and the Carba Nordmann/Poirel (NP) test were used to phenotypically screen carbapenem-resistant strains for carbapenemase production. Phenotypic characterization of carbapenemases was performed using the combined disk synergy test (CDST). Additionally, the presence of 12 carbapenemase genes in CRKP isolates was investigated. The DNA sequence of blaNDM and blaGES genes was determined. The BOX-PCR technique was used to determine the clonal relationship between CRKP isolates. Results All carbapenem-resistant isolates were related to K. pneumoniae. Susceptibility testing showed that 19.79% (19/96) of the collected isolates were carbapenem-resistant. Of the CRKP isolates, 68.42% (13/19) tested positive for the MHT and Carba NP test. CDST showed that 42.11% (8/19), 63.16% (12/19), 47.37% (9/19), and 73.68% (14/19) of the CRKP isolates tested positive for the inhibitory effect of clavulanic acid, sulbactam, phenylboronic acid, and tazobactam, respectively, while 84.21% (16/19) and 68.42% (13/16) tested positive for the inhibitory effect of EDTA and mercaptopropionic acid, respectively. It was found that 10.53% (2/19) of the isolates tested positive for the inhibitory effect of sodium chloride. Molecular investigation of carbapenemases showed that 26.32% (5/19), 73.68% (14/19), 21.05% (4/19), 10.53% (2/19), and 5.26% (1/19) of the isolates tested positive for blaNDM, blaOXA-48, blaOXA-181, blaOXA-51, and blaOXA-23, respectively. None of the isolates tested positive for blaOXA-40 and blaOXA-58. Two allelic variants of blaNDM (blaNDM-1 and blaNDM-25) were detected. BOX-PCR revealed high clonal relatedness between CRKP isolates. Conclusion MHT was more sensitive than Carba NP test for evaluating carbapenemase production and class D carbapenemase genes were the most prevalent of the 12 carbapenemase genes that were evaluated.

Background and objective Acinetobacter baumannii (A. baumannii) is a common nosocomial pathogen, which developed multi-drug-resistance to different classes of antibiotics including carbapenems. This study examined ten common carbapenemase genes among 32 carbapenem-resistant A. baumannii clinical isolates recovered from Taif, Saudi Arabia. Methods Isolates were phenotypically identified to the genus level by Vitek®2 and API 20NE®. The species level was confirmed by the amplification of bla OXA-51. The susceptibility for 21 different antibiotics was performed by Vitek 2 and modified Kirby-Bauer method. Isolates were genetically screened for 10 carbapenemases. Phylogenetic relatedness between isolates was determined by ERIC-PCR. Results Genotypically identified A. baumannii represented 100% of the total phenotypically identified Acinetobacter spp. All the carbapenem-resistant isolates were sensitive to polymyxin B and colistin. Among the other antibiotics, ampicillin/sulbactam and tigecycline were the most effective agents. 90.8% of the isolates were resistant to all ten investigated β-lactams. bla OXA-51, bla IPM, bla NDM and bla OXA-23 were detected in 100%, 87.5%, 62.5% and 59.4% of isolates, respectively. Also, bla VIM and bla OXA-40 were less prevalent and were detected in 9.3% and 3.1% of the isolates, respectively. In addition, bla KPC, bla OXA-48, bla OXA-58, bla OXA-181 were not detected in any isolate. The A. baumannii isolates were categorised into ten genotypes on the basis of the detected carbapenemase genes and ERIC-PCR revealed a remarkable clonal diversity among these isolates. Conclusion Class A and class D carbapenemase genes were the most commonly detected among carbapenem resistant A. baumannii (CRAB) clinical isolates.

Background: Quinolones are among the most effective antibiotics against Pseudomonas spp. Several chromosomal and/or plasmid-mediated quinolone-resistance mechanisms have been found in Pseudomonas. Plasmid-mediated quinolone-resistance (PMQR) is mediated by quinolone-resistance (QNR) proteins, modifying enzymes or efflux pumps. Only a few previous studies examined the prevalence of quinolone-resistance in the Kingdom of Saudi Arabia (KSA) and showed it is increasing. Mechanisms of quinolone-resistance among Pseudomonas spp. in the KSA; examined herein; have not been extensively studied. Methods: Ninety-two Pseudomonas isolates were collected and their resistance to seven different types of quinolones was determined by the microbroth dilution method. PMQR mechanisms were examined using a PCR screen to identify six PMQR genes including qnrA, qnrB, qnrD, qnrS, aac(6´)-Ib-cr, and qepA. Clonal relatedness of the quinolone-resistant isolates was determined by ERIC-PCR. Results: Of the isolates, 42.4% (39/92) were resistant to 1-7 of the tested quinolones. Gemifloxacin resistance was the lowest (28.3%) while resistance to the other six quinolones were ≥ 35%. The most common biotype among the 39 quinolone-resistant isolates was resistance to the seven tested quinolones (26/39; 66.7%). qnrD, qnrS, and aac(6´)-Ib-cr were found in 31 (79.5%), 31 (79.5%) and 28 (71.8%) of the 39 isolates, respectively, and all three genes together were found in 22 of the 39 isolates (56.4%). qnrA, qnrB, and qepA were not detected in any of the isolates and two isolates did not harbor any of the six tested genes. The isolates showed 38 different ERIC profiles and only two isolates (Pa16 and Pa17) had an identical profile. Conclusion: This is the first description of PMQR mechanisms among clinical Pseudomonas isolates from the KSA, which appears to be mainly mediated by qnrD, qnrS, and aac(6´)-Ib-cr.

Frankia strains isolated from Saudi Arabia, reported for the first time, were identified based on the morphological and molecular tools compared to those isolated from Egypt. All strains displayed typical morphological characterization of Frankia strains represented by branched hyphae, production of vesicles and sporangia. The phylogenetic analysis and relationships among Frankia strains were investigated by comparing 16S rRNA gene sequences. The analysis revealed three genetic groups which formed two clusters. The first cluster was composed of eight Frankia strains subdivided into two genetic groups (one group containing five strains; CgIT3 L2 , CgIS3 N2 , CgIS1 N1, CgIT7N2, and G5; the other group included of three strains: CgIT5L3, CgIS1 N2 , and CcI13). The second cluster was composed of only one genetic group of Frankia strain CgIS3 N1 . The strains in each genetic group exhibited similar genetic distances. All Frankia strains were able to reinfect their host of Casuarina species. For ability of these strains to resist heavy metals, our results proved that all Frankia strains isolated can resist Cu, Co, and Zn at low concentration except Pb which exhibit highly toxic effect at the same concentration used. Frankia strain G5 was proved to be the most resistant strain for heavy metals tested.

Inappropriate use of antibiotics in clinical settings is thought to have led to the global emergence and spread of multidrug-resistant pathogens. The goal of this study was to investigate the prevalence of genes encoding aminoglycoside resistance and plasmid-mediated quinolone resistance among clinical isolates of Klebsiella pneumoniae. All K. pneumoniae isolates were phenotypically identified using API 20E and then confirmed genotypically through amplification of the specific K. pneumoniae phoE gene. All isolates were genotyped by the enterobacterial repetitive intergenic consensus polymerase chain reaction technique (ERIC-PCR). Antibiotic susceptibility testing was done by a modified Kirby-Bauer method and broth microdilution. All resistant or intermediate-resistant isolates to either gentamicin or amikacin were screened for 7 different genes encoding aminoglycoside-modifying enzymes (AMEs). In addition, all resistant or intermediate-resistant isolates to either ciprofloxacin or levofloxacin were screened for 5 genes encoding the quinolone resistance protein (Qnr), 1 gene encoding quinolone-modifying enzyme, and 3 genes encoding quinolone efflux pumps. Biotyping using API 20E revealed 13 different biotypes. Genotyping demonstrated that all isolates were related to 2 main phylogenetic groups. Susceptibility testing revealed that carbapenems and tigecycline were the most effective agents. Investigation of genes encoding AMEs revealed that acc(6′)-Ib was the most prevalent, followed by acc(3′)-II, aph(3′)-IV, and ant(3′′)-I. Examination of genes encoding Qnr proteins demonstrated that qnrB was the most prevalent, followed by qnrS, qnrD, and qnrC. It was found that 61%, 26%, and 12% of quinolone-resistant K. pneumoniae isolates harbored acc(6′)-Ib-cr, oqxAB, and qebA, respectively. The current study demonstrated a high prevalence of aminoglycoside and quinolone resistance genes among clinical isolates of K. pneumoniae.

The extensive use of β-lactam antibiotics has led to emergence and spread of extended-spectrum β-lactamases (ESBLs). This study was conducted to investigate the prevalence of 7 different ESBL genes (blaTEM, blaSHV, blaCTX-M, blaVEB, blaPER, blaGES, and blaOXA-10) and O25b-ST131 high-risk clone among 61 clinical isolates of Escherichia coli. Also, one broad-spectrum β-lactamase (blaOXA-1) was investigated. This study was also constructed to evaluate iodometric overlay method in detection of ESBL production. Phenotypic identification of E. coli isolates using API 20E revealed 18 distinct biotypes. DNA fingerprinting using enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) differentiated all isolates into 2 main phylogenetic groups with 60 distinct genetic profiles. Elevated values of minimal inhibitory concentration (MIC)50 and MIC90 for third- and fourth-generation cephalosporins were observed. Phenotypic tests revealed that 85.24% of isolates were ESBL producers. The inci...

Recently, the residues or by-products of agriculture industry take attention for their valuable source of natural antioxidants. Taif rose (Rosa damascena trigintipetala Dieck) is considered one of the most important economic products of Taif, Saudi Arabia. In this study, the antioxidant and total phenolic contents of the defatted flowers of fresh Taif rose were investigated. The antioxidant activity was chemically determined using three methods; 1,1-diphenyl picrylhydrazyl (DPPH.) free radical scavenging activity, phosphomolybdenum method and reducing power activity. The methanol extract showed antiradical activity with SC50=49.44 mg/ml. Different fractions obtained from successive fractionation of the methanol extract with organic solvents of different polarities; chloroform (CHCl3), ethyl acetate (EtOAc) and n-butanol (n-BuOH); showed that, the EtOAc fraction had higher antiradical activity than n-BuOH fraction, and their respective SC50 were 15.62 and 36.29 mg/ml. On the other hand, CHCl3 fraction had a poor antiradical activity (SC50>100 mg/ml). The total phenolics, flavonoids, flavonols and RP-HPLC analysis of the methanol extract and its EtOAc and n-BuOH fractions were determined. The ethyl acetate fraction had the highest contents of phenolics, flavonoids and flavonols that correlated with the antioxidant activity. From this work, it is obvious that the by-product from concrete oil production of Taif rose could be used as a good inexpensive source of antioxidant polyphenolics.

Rose is one of the most economically important ornamental crops in the world. In this study, we analyzed nine macro- and microelements in soils and petals ofR. damascenaMill. cultivated in Shafa and Hada mountains. The amounts of the investigated macro- and microelements varied from one soil or petal sample to another and they were generally higher in most soil and petal samples of Shafa compared to Hada. On the other hand, the levels of the investigated elements in petal samples were not dependent on their levels in soil samples. While water extracts of the soil of farms of Shafa were slightly alkaline (pH 7.69), they were moderately alkaline (pH 8.04) in Hada farms. The amounts of oil produced by rose petals of Hada were relatively larger than those of Shafa. Amongst the five investigated constituents of the volatile oil of roses, the amounts of citronellol, geraniol, and eugenol were significantly larger in the volatile oil of rose petals of Hada compared to Shafa. This study suggests that the ecology of roses of both Hada and Shafa mountains is different and this is most likely reflected on the amount of volatile oil and its constituents. Therefore, further integrated multidisciplinary research correlating rose ecology, agronomy, and essential oil yield is highly recommended.

Previous work revealed that the defatted methanol (MeOH) extract of fruits of Conocarpus erectus L. (Combretaceae family) exhibited antioxidant, antibacterial and anti-cancer activities. In further studies of this valuable plant, the defatted MeOH extract of C. erectus fruits was subjected to chromatographic fractionation in a silica gel glass column followed by reversed-phase high-performance liquid chromatography-ultraviolet-electrospray ionisation spectrometry analysis (RP-HPLC-UV-ESI-MS). The major and sharp peaks in each sample were identified or tentatively identified based on matching with some standard compounds and a review of the literature. Ellagic acid, vescalagin/castalagin isomer and di-(hexahydroxy diphenoyl) galloyl hexose isomer were tentatively identified as major components with many hydrolysable types of tannins on the basis of a comparison of its mass patterns with relevant items in the literature. Gallic acid, kaempferol 3-O-β-d-glucopyranoside and quercetin 3-O-β-d-glucopyranoside were identified on the basis of matching retention time (t R) and mass spectra with the standards. Polymethoxylated flavonoid isomers were also tentatively identified. The antioxidant properties of all samples were found to be associated with the total content of phenolic compounds. This may be considered as the first detailed phytochemical report in identifying the phytochemicals in C. erectus fruits. Due to the high antioxidant activity exhibited by both the crude MeOH extract and its fractions, it could be used as an effective natural antioxidant after further in vitro and in vivo studies.

Bacillus subtilis mutants with altered penicillin-binding proteins (PBPs), or altered expression of PBPs, were isolated by screening for changes in susceptibility to beta-lactam antibiotics. Mutations affecting only PBPs 2a, 2b and 3 were isolated. Cell shape and peptidoglycan metabolism were examined in representative mutants. Cells of a PBP 2a mutant (UB8521) were usually twisted whereas PBP 2b (UB8524) and 3 (UB8525) mutants produced helices, particularly after growth at 41 degrees C. The PBP 2a mutant (UB8521) had a higher peptidoglycan synthetic activity than its parent strain whereas the opposite applied to the PBP 2b mutant UB8524. The PBP 3 mutant (UB8525) had a similar peptidoglycan synthetic activity to that of the parent strain when grown at 37 degrees C, but 40% higher activity after growth at 41 degrees C. The PBP 2a mutant (UB8521) exhibited the same wall thickening activity as the parent, but the PBP 2b and 3 mutants (UB8524 and UB8525) were partially defective in this respect. The changes in the susceptibility of PBP 2a, 2b and 3 mutants to beta-lactam antibiotics imply that these PBPs are killing targets, consistent with the fact that these PBPs are also important for shape determination and peptidoglycan synthesis.

Summary: The composition of membranes from whole cells and minicells of Bacillus subtilis strain BD474 was examined. Two-dimensional electrophoresis showed that the content of several individual polypeptides differed in the two membrane types. Whole cell membranes appeared to contain more penicillin binding protein (PBP) 2a. glycerol-3-phosphate dehydrogenase, succinate dehydrogenase and NADH dehydrogenase than minicell membranes, but less PBP2b, lactate dehydrogenase and malate dehydrogenase. Glycerol-3-phosphate dehydrogenase and succinate dehydrogenase were unstable, but the other enzymes and PBPs were stable after inhibition of protein synthesis by chloramphenicol. Minicells synthesized peptidoglycan because they incorporated 14C-labelled acetylglucosamine into acid precipitable material. However, the rate of incorporation in minicells was only 5% of the value observed in whole cells. Whole cell and minicell membranes contained the same polar lipids and fatty acids, but the whole cell membranes were enriched in phosphatidylglycerol, diglycosyldiacylglycerol, iso-C15 and anteiso-C15 fatty acids, but depleted of phosphatidylethanolamine, iso-C14, iso-C16, n-C16 and anteiso-C17 fatty acids.

The use of phenethyl alcohol (PEA) as a probe for signal sequence-dependent protein translocation in minicells was examined. Processing of beta-lactamases and tonA was inhibited by PEA at concentrations which did not affect production of the alpha and gamma forms of penicillin binding protein (PBP) lb. The PBPlbs are believed to lack leader sequences whereas the other proteins contain them. Processing of a beta-lactamase which shares the murein-lipoprotein export pathway was relatively resistant to PEA, consistent with previous findings in whole bacteria. The results reported here suggest that PEA is a suitable probe for leader sequences in the minicell system. By using PEA we predict that PBP4 does not require a leader sequence for membrane insertion.