Esherichia Coli Research Articles

Prevalence of Pathogenic Bacteria in Open Drains and its Public Health Implications for Water Resources in Port Harcourt, Southern Nigeria

Wastewater and sediment samples from the open drains along the Ntanwogba creek were collected from five (5) different sites and analyzed for the presence of pathogenic bacteria. Microbiological studies involved the isolation and characterization of isolates by assessing the gene/nucleotide structure of the bacterial community through the polymerase chain reaction study. Results of the analysis show that the following bacteria were identified from the samples. The gram-negative bacteria include, Proteus mirabilis M18, Klebsiella pneumoniae strain DSM 30104, Burkolderia multivorans strain AUO, Plesiomonas shigelloides strain 187-907R, Pseudomonas fluorescens strain PF1, Esherichia coli, Enterobacter asburiae strain TYP8, Proteus mirabilis M19, Pseudomonas nitroreducens strain LBQSKN1, while gram-positive bacterium was Bacillus ginsengisoli strain A1Cr. Results obtained showed that both wastewater and sediment samples had higher microbial counts from the various sampling sites. Excess untreated wastewater can run off or percolate down to groundwater, causing contamination of drinking water supplies with faecal wastes and other pollutants which may contribute significantly to the spread of diseases amongst our population. This shows that the wastewater effluents and the receiving water bodies could pose a potential health risk to the surrounding communities who depend on these water resources for various domestic activities.

Foodborne pathogens.

Foodborne pathogens are causing a great number of diseases with significant effects on human health and economy. The characteristics of the most common pathogenic bacteria (Bacillus cereus, Campylobacter jejuni, Clostridium botulinum, Clostridium perfringens, Cronobacter sakazakii, Esherichia coli, Listeria monocytogenes, Salmonella spp., Shigella spp., Staphylococccus aureus, Vibrio spp. and Yersinia enterocolitica), viruses (Hepatitis A and Noroviruses) and parasites (Cyclospora cayetanensis, Toxoplasma gondii and Trichinella spiralis), together with some important outbreaks, are reviewed. Food safety management systems based on to classical hazard-based approach has been proved to be inefficient, and risk-based food safety approach is now suggested from leading researchers and organizations. In this context, a food safety management system should be designed in a way to estimate the risks to human health from food consumption and to identify, select and implement mitigation strategies in order to control and reduce these risks. In addition, the application of suitable food safety education programs for all involved people in the production and consumption of foods is suggested.

Effect of Inorganic Salts on the Thermotolerance and Probiotic Properties of Lactobacilli Isolated from Curdled Milk Traditionally Produced in Mezam Division, Cameroon

The industrial production of most food and probiotic products often requires processing involving high temperatures and physiological stress causing loss of viability of probiotic microbial strains. The viability and stability of probiotic strains is a key determinant of their efficacy during administration in human and animal. Thermotolerance is actually a very important feature for probiotic undergoing industrial processing. This paper aimed at assessing the effect of some mineral salts on the thermotolerance and the probiotic properties of lactobacilli isolated from curded milk produced in Mezam Division, Cameroon. Lactobacilli were isolated by pour plate method on de Man Rogosa and Sharpe (MRS) agar. Lactobacilli were selected based on their ability to suppress in-vitro and in-vivo food borne pathogenic bacteria; Salmonella enterica serovar Enteridis and Esherichia coli. Inhibitory activities against these food borne pathogens were performed by disc diffusion method on Mueller Hinton agar. In-vivo inhibition of Salmonella was achieved using oral administration by gavage of (1.0 × 109 CFU/ml) of selected probiotic strain suspended in sterile water. Thermotolerance was assessed by measuring the survival rate of the strain after heating at various temperatures in the presence and absence of mineral salts. Resistance to bile was determined by measuring the survival rate of probiotics after incubation in the presence of oxgallbille and mineral salts. Two catalase negatives isolates were selected based on their capacity to exhibit inhibitory activities in-vitro and in-vivo against food borne pathogens. They were identified as strain of Lactobacillus casei (LS3) and Lactobacillus plantarum (LM4). These strains exhibited significant reduction (P Salmonella count in caeca swabs of infected chick model. The calcium and magnesium salts increased significantly (P < 0.05) the thermo-tolerance and resistance to bile of probiotic strains studied. These results suggested that calcium and magnesium could be used to monitor the viability of probiotic strains in probiotic products.

Enhancement of solubility, purification and inclusion-bodies-refolding of an active pectin lyase from Penicillium occitanis expressed in Escherichia coli

Pectin lyase (pnl) is the only pectinase able to hydrolyze directly the highly methylated pectin without liberating the toxic methanol and without disturbing ester content responsible for specific aroma of juices. The cDNA of Penicillium occitanis pnl (mature form) was cloned into pET-21a as expression vector and over-expressed into Esherichia coli. Most of recombinant pnl was expressed as inclusion bodies. Pnl activity was confirmed by colorimetric assay. To enhance the solubility yield of the expressed pnl, the effects of induction temperature, host strain and expression level were optimized. Maximal production of functional pnl was obtained after induction by 0.4mM IPTG at 30°C and 150rpm for 16h. Interestingly, the use of Origami host strain, having an oxidized cytoplasm favoring disulfide bonds formation required for the active conformation of the enzyme, has significantly improved the yield of the soluble active form of recombinant pnl. This pnl was successfully purified through a single step purification using His-Trap affinity column chromatography. This work is the first to report pnl expression into Origami strain. Alternatively, the inclusion bodies were isolated, denatured by high concentration of urea and gradually refolded by successive dialysis, leading to their transformation into soluble and active form.

A bioactivity guided study on the antibacterial activity of Hertia cheirifolia L. extracts.

This study was carried out with the objective to investigate the antibacterial activity of Hertia cheirifolia L. extracts against Gram-positive and Gram-negative strains including Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633), Bacillus licheniformis, Esherichia coli (ATCC 8739), Pseudomonas aeruginosa (ATCC 9027), Salmonella enterica (CIP 8039) and Salmonella typhimirium. The results of this antibacterial screening showed that the ethyl acetate (EtOAc) extracts had the best activity against the tested microorganisms. A bioassay-oriented fractionation approach for the more active extract (roots ethyl acetate extract) led to the obtaining five sub-fractions. Furthermore, these sub-fractions were also tested for antimicrobial activity and the best results were obtained for the roots EtOAc sub-fraction (C) with MICs values between 0.039 and 0.156mg/mL. Reversed-phase high performance liquid chromatography (RP-HPLC) analysis indicated that the major phenolic components of active (EtOAc) extracts and sub-fraction (C) are fisetin hydrate (82.06%), trans cinnamic acid (63.66%), gallic acid (38.97%) and myricetin (20.92%). These results may help to improve these natural antibacterial substances that could serve as selective agents for bacterial diseases.

Biosynthesis of palladium nanoparticles by using Moringa oleifera flower extract and their catalytic and biological properties

The biosynthesis of nanostructured biopalladium nanoparticles (PdNPs) from an aqueous solution of crystalline palladium acetate is reported. For the synthesised PdNPs in solution, an agroforest biomass waste petal of Moringa oleifera derived bis-phthalate was used as natural reducing and biocapping agents. Continuous absorption in the UV region and subsequent brown colour change confirmed the formation of PdNPs. A strong surface plasmon peak for PdNPs occurred at 460nm. PdNPs were characterized by SEM with EDX, FTIR, TEM and DLS. The chemical composition of the aqueous extract was determined by GC–MS coupled with FTIR and 1NMR. The catalytic degradation effect by PdNPs on industrial organic toxic effluents p-nitrophenol (PNP) and methylene blue dye was monitored by UV Spectroscopy. On the other hand PdNPs catalysed the base mediated suzuki coupling reaction for biphenyl synthesis, in water. Moreover, PdNPs were found to be reusable catalysts. Toxicity studies of PdNPs showed that the death of brine shrimp to be <50%. Therefore, PdNPs displayed potential for further anticancer studies via tumour cell lines. The in vitro cytotoxicity evaluation of the extract capped nanoparticles was carried out using human lung carcinoma cells (A549) and peripheral lymphocytes normal cells by MTT cell viability assay. Also, PdNPs showed antibacterial activity against Enterococcus faecalis among the different tested strains, including Bacillus cereus, Staphylococcus aureus, Esherichia coli and Candida albicans, Candida utilis.

Morphofunctional state of the liver of rat progeny from mothers, infected with Esherichia Coli (experimental research).

Background: As a result of extensive and sometimes uncontrolled use of antibacterial drugs the role of conditionally pathogenic microbiota in the development of inflammatory processes significantly increased. An important problem is infections caused by conditionally pathogenic microflora in pregnant women, especially important role of E.coli. Our study of morphofunctional state of progeny liver from mothers with infections caused by Escherichia coli, will clarify special features of infection impact on fetus liver. Objective: to identify morphological and functional features of liver of fetuses, who were born from mothers with prolonged subacute infectious process caused by Escherichia coli. Methods: In order to detect morphofunctional state of the liver of rat fetuses, from mothers, who were infected by Escherichia coli, we conducted two experiments: modeling of chronic intrauterine hypoxia (CIH) and modeling of infection. The experimental material was divided into three groups: control group, group with chronic intrauterine hypoxia - CIH and main group – infected by Escherichia coli. Results: In our study we revealed significant differences between control group and CIH group, as well as between the main group and CIH group. In CIH group liver we found: signs of edema, central venous congestion with hemorrhages in center of lobules. Hepatocytes were in condition of protein dystrophy, sometimes we identified foci of necrosis, which is likely due to influence of hypoxia. In main group we identified the following morphological changes: edema, hyaline droplet degeneration of hepatocytes, also we found, hyperchromatic vacuolated cytoplasm, sometimes we determined non-nuclear, necrotic cells and also we found hepatocytes with larger hyperchromatic nuclei. In liver cells we noticed the increase of degenerative changes accompanied by severe edema of stroma. Conclusion: When mother is infected by Escherichia coli in her offsprings liver we can see developing of alterative changes manifested by dystrophy and necrobiosis of hepatocytes, violation of structure of hepatic lobules on the background of moderately severe compensatory and adaptive processes.

Evaluation of the anti-diarrheal activity of the hydromethanolic root extract of Rhus tripartita (Ucria) (Anacardiacae).

Rhus tripartita (Anacardiacae) is a plant which is traditionally used for the treatment of ulcer and diarrhea in Tunisia. However, the scientific basis for this usage has not been well established. The core aim of the present study is to evaluate the antidiarrheal activity of Rhus tripartita root methanolic extract (RRE). The antidiarrheal activity of RRE oral doses (50, 100, 200 and 300mg/kg) was evaluated using the castor oil-induced diarrhea, the intestinal fluid emptying method and the normal intestinal transit test. The antibacterial activity was tested against four pathogenic bacteria using two methods. The RRE was also phytochemical studied. Diarrhea experiments showed a protective effect of the RRE which produced a significant (p<0.05) and dose-dependent reduction of all the diarrhea parameters. It delayed the onset of diarrhea, produced a significant decrease in the frequency of defecation and the diarrhea score severity and decreased the volume of intestinal fluid induced by castor oil as well as the propulsion intestinal transit. The effect of the extract at the highest dose (300mg/kg) was similar to that of loperamide, the standard anti-diarrheal drug (10mg/kg). The anti-bacterial activity test showed that RRE exhibited a great inhibition activity against four pathogenic bacteria strains (Esherichia coli, Salmonella typhimurium, Salmonella argenosa, Staphylococcus aureus). Oral administration of the extract up to 3g/kg did not produce any acute toxicity in rats. The preliminary phytochemical screening of the RRE revealed the presence of flavonoids, tannins, and polyphenols. Results showed that RRE at 300mg/kg possesses the highest anti-diarrheal activity possibly mediated by the inhibitory effects on gastrointestinal propulsion and intestinal fluid accumulation.

PENELUSURAN FUNGI ENDOFIT SEBAGAI PENGHASIL SENYAWA ANTIBIOTIKA DARI DAUN NANAS (Ananas comosus (L) Meer)

A search endophytic fungi from the leaves of pineapple ( Ananas comosus (L) Merr) as a producer of antibiotic compounds will be carried out in order to obtain the endophytic fungi that have the ability to produce bioactive compounds useful as antibiotics.. Results of endophytic fungi isolates obtained six fungal isolates (IJA 1, IJA 2, IJA 3, IJA 4, IJA IJA 5 and 6), which have a different macroscopic characterization of forms, edge and elevation colonies. Isolates pure microbial fermentation results in the test antibiotic activity against some bacteria using agar diffusion test. All isolates pure fermentation results showed inhibitory activity against all bacteria in test as Bacillus subtilis, Esherichia coli , Pseudomonas aeruginosa , Salmonella thypi , Shigella dysenteriae , Staphylococcus aureus , Streptococcus mutans , and Vibrio cholerae . The inhibition of fungi isolates shown in (IJA 4) with a 26 mm zone of inhibition against Esherichia coli bacteria.

PENELUSURAN FUNGI ENDOFIT SEBAGAI PENGHASIL SENYAWA ANTIBIOTIKA DARI DAUN NANAS (Ananas comosus (L) Meer)

A search endophytic fungi from the leaves of pineapple ( Ananas comosus (L) Merr) as a producer of antibiotic compounds will be carried out in order to obtain the endophytic fungi that have the ability to produce bioactive compounds useful as antibiotics.. Results of endophytic fungi isolates obtained six fungal isolates (IJA 1, IJA 2, IJA 3, IJA 4, IJA IJA 5 and 6), which have a different macroscopic characterization of forms, edge and elevation colonies. Isolates pure microbial fermentation results in the test antibiotic activity against some bacteria using agar diffusion test. All isolates pure fermentation results showed inhibitory activity against all bacteria in test as Bacillus subtilis, Esherichia coli , Pseudomonas aeruginosa , Salmonella thypi , Shigella dysenteriae , Staphylococcus aureus , Streptococcus mutans , and Vibrio cholerae . The inhibition of fungi isolates shown in (IJA 4) with a 26 mm zone of inhibition against Esherichia coli bacteria.

Isolation and Characterisation of Esherichia coli O157 in Human Stool Samples from Parts of Kaduna Metropolis Nigeria

Esherichia coli O157 is pathogenic strain of Esherichia coli that is known to cause diarrhoea leading to fluid loss, electrolyte imbalance and other severe complications like haemolytic uraemic syndrome. This work was therefore aimed at isolating and serologically characterising Esherichia coli O157 from human stool with the set objectives of identifying the risk factors associated with diarrhoea and determining the serological characteristics of Esherichia coli isolates. A total of one hundred and forty four (144) stool samples were collected from patients with age ranging from zero to sixty (0-60) years, statistical analysis of the risk factors showed that only zero to five years age range of the respondents had a significant statistical difference of 0.012 (P<0.05). The presumptive Esherichia coli isolates that appeared as green metallic sheen on Eosin Methylene Blue agar were picked and confirmed biochemically as Esherichia coli using Microgen biochemical test kit. The confirmed E. coli isolates were then cultured on Sorbitol MacConkey Agar and the two isolates that appeared colourless on SMAC were confirmed serologically as Esherichia coli O157 using the latex agglutination test kit. Although 1.39% prevalence rate of Esherichia coli O157 was obtained it is pertinent to note that, Esherichia coli O157 is becoming a public health threat because of the debilitating effects it has on humans and also due to its low infectivity dose. There is therefore, the need for more public awareness to educate our citizens on ways of improving on the unsanitary environment.

Development of robust in vitro RNA-dependent RNA polymerase assay as a possible platform for antiviral drug testing against dengue.

NS5 is the largest and most conserved protein among the four dengue virus (DENV) serotypes. It has been the target of interest for antiviral drug development due to its major role in replication. NS5 consists of two domains, the N-terminal methyltransferase domain and C-terminal catalytic RNA-dependent RNA polymerase (RdRp) domain. It is an unstable protein and is prone to inactivation upon prolonged incubation at room temperature, thus affecting the inhibitor screening assays. In the current study, we expressed and purified DENV RdRp alone in Esherichia coli (E. coli) cells. The N-terminally His-tagged construct of DENV RdRp was transformed into E. coli expression strain BL-21 (DE3) pLysS cells. Protein expression was induced with isopropyl-β-D-thiogalactopyranoside (IPTG) at a final concentration of 0.4mM. The induced cultures were then grown for 20h at 18°C and cells were harvested by centrifugation at 6000xg for 15min at 4°C. The recombinant protein was purified using HisTrap affinity column (Ni-NTA) and then the sample was subjected to size exclusion chromatography, which successfully removed the degradation product obtained during the previous purification step. The in vitro polymerase activity of RdRp was successfully demonstrated using homopolymeric polycytidylic acid (poly(rC)) RNA template. This study describes the high level production of enzymatically active DENV RdRp protein which can be used to develop assays for testing large number of compounds in a high-throughput manner. RdRp has the de novo initiation activity and the in vitro polymerase assays for the protein provide a platform for highly robust and efficient antiviral compound screening systems.

Extraction of Functional Compounds from Plantago Lanceolata Plantand its Effect on Bacteria Causing Renal Diseases

Seven extracts were prepared from the fresh and dried leaves of Plantagolanceolataplant. Various specific chemical reagents were used to differentiate several functional groups extracts .The results of the experiments undertaken showed the presence of certain chemical compounds (phenols ,tannins ,glycosides and polysaccharides ) and absence of proteins in six extracts . Whereas extract number 7 gave only tannins and phenols .pH measurements were performed for all the extracts , they were ranging from 5.1 to 5.3 . The results of the effect of inhibition test that was conducted by employing pathogenic bacteria of renal disease (Esherichia coli,Salmonelatyphi , Shigellaspp. , Klebsiellaspp. , Proteus mirabilis ) occurring of interference . This interference was happened between the phenols and tannins with glycosides and polysaccharides led to the absence of the inhibition in extracts 1-6.But in case of extract No. 7 , when glycosides and polysaccharides washed , different diameters of inhibition ( 18.3 , 16.3 , 21 , 19 mm ) zone were appeared for all pathogenic bacteria (Esherichia coli ,Salmonelatyphi , Shigella spp. , Klebsiella spp. , Proteus mirabilis ) at certain concentration ( 100 mg/ml ) The results showed that the diameter of the inhibition zone was as a function of concentration of the extract at the range studied (12.5 , 25 , 50 , 100 mg/ml ) and the lowest concentration ( 12.5 mg/ml ) represented the minimum inhibitory concentration ( MIC ) .

Microorganisms Associated with Post-Harvest Spoilage of Tomato (Lycopersicum esculentum) in Makurdi, Central Nigeria

Microorganisms associated with post-harvest spoilage of tomato fruits in Makurdi were evaluated. Random sampling techniques were used to pick 250 spoilt tomato fruits from North-bank, Wurukum, High level, Wadata and Modern markets. The bacteria isolated were Bacillus cereus, Bacillus subtillis, Esherichia coli and Staphylococcus aureus while isolated fungi included Aspergillusspp, Alternaria species, Rhizopusspp, Candida species and Fusarium species. The bacteria isolated, from the spoilt tomato fruits sampled from Wurukum market had the highest colony forming unit of 6.5 x 10 (CFU/ml) followed by the ones sampled from Wadata, High-level, North-bank and Modern markets having 5.8 x 10 6 (CFU/ml), 4.3 x 10 6 (CFU/ml), 4.3 x 10 6 (CFU/ml), and 2.8 x 10 6 (CFU/ml) respectively. The fungi isolated from the spoilt tomato fruits from Wadata market had the highest colony forming unit of 6.7 x 10 (CFU/ml) followed by the samples from Wurukum, North-bank, High-level and Modern markets with 5.2 x 10 (CFU/ml), 4.6 x 10 (CFU/ml), 4.4 x 10 (CFU/ml) and 4.2 x 10 (CFU/ml) respectively. Using the same sampling techniques pathogenicity test on fifty (50) healthy tomato fruits from the same markets confirmed that bacteria and fungi that were earlier identified on the spoilt tomato fruits were still responsible for the spoilage, showing that deterioration of tomato fruits in Makurdi markets is due to the activities of these bacteria and fungi pathogens. Proper sanitary measures should be taken to improve harvesting and handling of tomato fruits to reduce spoilage caused by these pathogens.

Detection of bacterial agents associated with appendicitis At Al-Nassyriah city

The present study was include examination of the content of 100 surgical removed appendices for identify thebacteria found in flamed appendix cavity. The study recorded infection percentage by intestinal bacteria reached 83%, fecalith 6% and body foreign 2%. The results showed that the single infection percentage was 77% included infection of Esherichia coli, Bacteroides sp, Pseudomonas sp, Lactobacillus sp, Staphylococcus auerus, Salmonella sp, Proteus sp, Klebsiella sp and Yersinia sp by percentages (33%, 15%, 11%, 7%. 4%, 2%, 2%, 2%, 1%) respectively. Dual infection percentage (6%) included infection of Esherichia coli+ Bacteroides sp, Esherichia coli+ Salmonella sp, Pseudomonas sp+ Lactobacillus sp by percentages were (3%, 2%, 1%) respectively.

Assessment of the Microbiological Quality of Public Restaurants and Street Vended Ready-To-Eat “Koshari” Meals

Ninety ?Koshari? meals samples were collected from some restaurants and street vendors located in six public quarters in central Cairo, to determine the microbiological quality of them directly after cooking and preparing and after 4 &amp; 8 hrs of storage at room temperature. These samples examined for aerobic bacteria, Esherichia coli and coagulase positive Staphylococci to conduct a preliminary microbial risk assessment for them in” koshari “meals. According to the CDPH (2009) only 53 samples (59%) were of satisfactory microbiological quality for Aerobic plate count (APC) and 81 samples (90%) were positive for E. coli cells and 58% of them (47 samples) are acceptable quality. About coagulase positive S. aureus, 28 samples (31.1 %) were positive and only 60.7% of them (17 samples) of satisfactory microbiological quality.Moreover, the percentage of unacceptable microbiological quality samples tested (potentially hazardous) reached to 36 samples (40%), 29 samples (32.2%), and 17 samples (18.9%) for APC, E. coli and S. aureus respectively, after 8 hrs of storage at room temperature. This study reveals that “Koshari” meals sold on the public areas are unwholesome and could be a potential source of food-borne bacteria pathogens if not properly handled. Option might be to suggest that the product should be consumed within short time of purchase in these places. Improvements in processing and handling are required and the need of food-borne bacteria disease surveillance indicated. In addition, it was evident that the Egyptian Food Code needed new legal revisions.Int J Appl Sci Biotechnol, Vol 3(3): 452-458

Reducing Environmental Toxicity of Silver Nanoparticles through Shape Control.

The use of antibacterial silver nanomaterials in consumer products ranging from textiles to toys has given rise to concerns over their environmental toxicity. These materials, primarily nanoparticles, have been shown to be toxic to a wide range of organisms; thus methods and materials that reduce their environmental toxicity while retaining their useful antibacterial properties can potentially solve this problem. Here we demonstrate that silver nanocubes display a lower toxicity toward the model plant species Lolium multiflorum while showing similar toxicity toward other environmentally relevant and model organisms (Danio rerio and Caenorhabditis elegans) and bacterial species (Esherichia coli, Bacillus cereus, and Pseudomonas aeruginosa) compared to quasi-spherical silver nanoparticles and silver nanowires. More specifically, in the L. multiflorum experiments, the roots of silver nanocube treated plants were 5.3% shorter than the control, while silver nanoparticle treated plant roots were 39.6% shorter than the control. The findings here could assist in the future development of new antibacterial products that cause less environmental toxicity after their intended use.

Molecular cloning and characterization of a novel GH13 saccharifying α‐amylase AmyC from Corallococcus sp. EGB

A novel amylase AmyC gene (amyC) from Corallococcus sp. EGB was cloned and expressed in Esherichia coli. Analysis of the sequence homology showed that AmyC shared 92% identity with the putative α‐amylase from Corallococcus coralloides DSM 2259 and formed a separate branch from other amylases. The recombinant AmyC (rAmyC) was purified and biochemically characterized. rAmyC hydrolyzes various starch and maltooligosaccharides larger than G4 to glucose to maltotetraose without production of other oligosaccharides, indicating that it is a special saccharifying α‐amylase. AmyC possesses weak but significant α‐1, 6‐bond cleaving activity and transglycosylation activity. The time course of the reaction with maltotriose as a substrate evidently showed the formation of oligosaccharide of degree of polymerization (DP4) by glycosyl transfer. The substrate specificities and end products analysis showed that the hydrolytic pattern of rAmyC is unique. rAmyC exhibited maximum hydrolysis activity at 50°C in 50 mM sodium phosphate buffer (pH 6.0) with a specific activity of 180 U/mg. Its activity towards starch was independent of calcium ions and activated by dithiothreitol. These results indicate that AmyC is a novel endo multifunctional amylase possessing distinct characteristics.

Synthesis, Characterization, and In Vitro Antimicrobial and Antifungal Activity of Novel Acridines

Novel acridines (4a – 4l) were synthesized by reaction of tetraketones (3a, 3b) and aromatic amines. The structures of compounds were characterized by FT-IR, 1H NMR, mass spectroscopy, and elemental analysis. Furthermore, all the synthesized compounds were tested in vitro for their antimicrobial and antifungal activity. The results were compared with conventional reference antibiotics. Many of the acridine compounds considerably reacted against Esherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis, and Staphylococcus aureus. Particularly, compound 4k showed more pronounced activity than reference antibiotics against Salmonella enteritidis. All the compounds showed moderate activities against Candida albicans and Candida glabrata.

Comparative Investigation of the Antibacterial and Antifungal Potentials of the Extracts of Watermelon (Citrullus lanatus) Rind and Seed

Aim: To investigate the antibacterial and antifungal potentials of the crude ethanol and aqueous extracts of watermelon (Citrullus lanantus) rind and seed. Study Design: The fruits were purchased from a local market and identified in the Department of Plant Science and Biotechnology, Michael Okpara University of Agriculture Umudike, Nigeria by a taxonomist. The rind and seed samples were extracted using ethanol (95%) and water and the crude extracts screened for antibacterial and antifungal potentials. Place and Duration of Study: Department of Biochemistry, Michael Okpara University of Agriculture Umudike, Nigeria and National Root Crops Research Institute Umudike, Nigeria, between August, 2014 and November, 2014. Methodology: The ethanol and aqueous extracts of watermelon (Citrullus lanantus) rind (EER and AER) and seed (EES and AES), each at a concentration of 100 mg/ml, were investigated by welldiffusion method for activity against ten pathogens. Results: The EER exhibited the highest activity against the bacterium, Esherichia coli (6.0) and the fungus, Candida albican (4.0). The least activity was in the EES against the fungus, Trichosporo bepelli (0) followed by EER and AES against the bacterium, Staphylococcus aureus (1.0). For the Original Research Article Cemaluk; EJMP, 9(4): 1-7, 2015; Article no.EJMP.18142 2 bacterial strains, the highest mean activity (4.0) and mean susceptibility (4.50), respectively was in the EER and Esherichia coli whereas the least mean activity (3.0) and mean susceptibility (1.50), respectively was in AES and Staphylococcus aureus. For the fungal strains, the highest mean activity (2.5) and mean susceptibility (3.0), respectively was in the EER, AER, AES and Candida albican whereas the least mean activity (1.25) and mean susceptibility (1.25) was in EES and Trichosporo bepelli. The activity against the studied pathogens however was higher in the EE than in the AE of the rind and seed, suggesting the preference to the EE for higher pharmacologic activity. Conclusion: The extracts (EER, AER, EES and AES) exhibited activity against the tested strains, especially Escherichia coli and Candida albicans. The study underscores the overriding potency of EER against the bacterium, Escherichia coli and the fungus, Candida albicans, and the nonsusceptibility of the fungus, Trichosporo bepelli to EES. Further works, however are needed to validate reliability and possible exploitation in nutraceutical formulations and in ethnomedication.