An-Najah Staff

A hydroponic system as decentralised wastewater treatment and reuse was tested. The hydroponic system was built in a greenhouse in order to improve growth conditions for plants including orchard trees, vegetables and flowers. The experiment was conducted from 2007 until present, in a model greenhouse which was installed at An-Najah National University’s new campus, in hydroponic barrels and channels filled with soilless-media. Findings showed that the hydroponic system is effective in reducing various pollution loads. The performance of hydroponic barrels was better than the channels, and winter squash and trees were better than flowers and vegetables.

Streptococcus pneumoniae is one of the most important bacterial pathogens that affect respiratory system. The occurrence of multidrug-resistant strains of S. pneumoniae necessitates the discovery of new classes of anti-pneumonia drugs. As some of the medicinal plants and their extracts have antibacterial activity, we aimed to investigate the antibacterial potential of five Palestinian wild medicinal plants including Echinops adenocaulos, Parietaria judaica, Urtica urens, Verbascum fruticulosum and Vitex agnus-castus against multidrug-resistant strain of S. pneumoniae, which was screened for its antibiotic resistance profile showing 67% resistance of the tested antibiotics. In this research micro-broth dilution method was used to study the inhibitory activity of ethanol, distilled water and Zamzam water extracts of all plants under investigation. The obtained results showed that all Zamzam extracts of the five studied plant species inhibited the growth of S. pneumoniae. It was clearly noticed that there was a difference in the antibacterial activity between distilled water and Zamzam water extracts recording higher activity in the Zamzam water extract of some of the studied plant species. Verbascum fruticulosum distilled water extract was the most effective one with MIC equal to 0.195 mg/ml. In general, both water extracts were more bioactive than the ethanol extracts for all the examined plants. These results confirmed the possibility of using these plant species in medicine and pharmaceutical industry of new drugs for the treatment of multidrug-resistant clinical isolates of S. pneumoniae.

Streptococcus pneumoniae is one of the most important bacterial pathogens that affect respiratory system. The occurrence of multidrug-resistant strains of S. pneumoniae necessitates the discovery of new classes of anti-pneumonia drugs. As some of the medicinal plants and their extracts have antibacterial activity, we aimed to investigate the antibacterial potential of five Palestinian wild medicinal plants including Echinops adenocaulos, Parietaria judaica, Urtica urens, Verbascum fruticulosum and Vitex agnus-castus against multidrug-resistant strain of S. pneumoniae, which was screened for its antibiotic resistance profile showing 67% resistance of the tested antibiotics. In this research micro-broth dilution method was used to study the inhibitory activity of ethanol, distilled water and Zamzam water extracts of all plants under investigation. The obtained results showed that all Zamzam extracts of the five studied plant species inhibited the growth of S. pneumoniae. It was clearly noticed that there was a difference in the antibacterial activity between distilled water and Zamzam water extracts recording higher activity in the Zamzam water extract of some of the studied plant species. Verbascum fruticulosum distilled water extract was the most effective one with MIC equal to 0.195 mg/ml. In general, both water extracts were more bioactive than the ethanol extracts for all the examined plants. These results confirmed the possibility of using these plant species in medicine and pharmaceutical industry of new drugs for the treatment of multidrug-resistant clinical isolates of S. pneumoniae.

This study has been carried out to evaluate the possible In vitro interaction between ethanolic extracts of Rus coriaria (seed), Sacropoterium spinosum (seed) and Rosa damascena (flower) and certain known antimicrobial drugs including oxytetracycline HCl, penicillin G, cephalexin, sulfadimethoxine as sodium and enrofloxacin. Synergy testing of these extracts and antibiotics was carried out against 3 multidrug-resistant Pseudomonas aeruginosa strains using microdilution method. Results of this study showed that there is a decrease in the MIC in case of combination between ethanolic plant extracts and test antimicrobial agents. The most interesting result that the combination between R. coriaria and these antibiotics, which showed a high decrease in MIC and a strong bactericidal activity against these strains. These results may indicate that combinations between R. coriaria extract and these antibiotics could be useful in fighting emerging drug-resistance P. aeruginosa, this may due to that R. coriaria extract contain natural inhibitors working by different mechanisms or inhibiting efflux pumps. Now we have experiments underway leading to the identification of the active molecules present in R. coriaria. Further, in vivo experiments are needed to confirm Pseudomonal protection

Tomato, considered one of most important and popular crop, was infected by Tomato Yellow Leaf Curl Virus (TYLCV) which causes significant yields loss. Biological and molecular tools were used to evaluate the TYLCV incidence on tomatoes grown under commercial conditions. A total number of 72 tomato plants from each eight different tomato cultivars commercially planted in Palestine were tested for their virus infection which occurred naturally. The virus incidence was reported biologically based on visual inspections for the disease symptoms and molecularly by PCR tests, in two growing season periods: Summer (2006) and spring (2007). As a result, no cultivars were found “immune” to virus infection. However, fundamental differences in symptoms development and severity had been discovered. This study, which was carried out for the first time in Palestine, showed that some cultivars such as “3060” could be targeted as promising virus-tolerant ones. The sensitivity of molecular methods over bioassays was evaluated, and combined methods were suggested for any cultivars resistance assessments. Besides, research results revealed that the experimental conditions in Spring were not in favor of the virus spread, as the main virus vector (Bemisia tabaci) population number would be lower in the Summer season; thus the Spring season is seen as the best one for farmers to escape from TYLCV infections.

This study has been carried out to evaluate the possible In vitro interaction between ethanolic extracts of Rus coriaria (seed), Sacropoterium spinosum (seed) and Rosa damascena (flower) and certain known antimicrobial drugs including oxytetracycline HCl, penicillin G, cephalexin, sulfadimethoxine as sodium and enrofloxacin. Synergy testing of these extracts and antibiotics was carried out against 3 multidrug-resistant Pseudomonas aeruginosa strains using microdilution method. Results of this study showed that there is a decrease in the MIC in case of combination between ethanolic plant extracts and test antimicrobial agents. The most interesting result that the combination between R. coriaria and these antibiotics, which showed a high decrease in MIC and a strong bactericidal activity against these strains. These results may indicate that combinations between R. coriaria extract and these antibiotics could be useful in fighting emerging drug-resistance P. aeruginosa, this may due to that R. coriaria extract contain natural inhibitors working by different mechanisms or inhibiting efflux pumps. Now we have experiments underway leading to th e identification of the active molecules present in R. coriaria. Further, in vivo experiments are needed to confirm Pseudomonal protection.

Disk diffusion and micro-dilution techniques were used to determine the antibacterial activity of water, ethanolic and methanolic extracts of Rhus coriaria ripe berries against five clinical bacterial strains (Methicillin-resistant Staphylococcus aureus (MRSA), multi-drug resistant Pseudomonas aeruginosa, enterohemorrhagic Escherichia coli O157 (EHEC), Proteus vulgaris and Klebsiella pneumoniae). Bacillus subtilis ATCC6633 was used as a reference strain. The zone of inhibition varies depending on bacterial species and type of extract. The average diameter of inhibition zones ranges from 0 to 19 mm, 15 to 25 mm and 15 to 22 mm for water, ethanolic and methanolic extract, respectively. The MIC value of ethanolic extract was 1.25 mg/ml against MRSA, EHEC, P. aeruginosa and Proteus vulgaris, while 0.156 mg/ml against B. subtilis. In general these results showed that the antibacterial activity of R. coriaria ripe berries extracts was more effective against Gram-positive bacteria than Gram-negative.

Enterotoxin genes (sea-see) in Staphylococcus aureus isolates recovered from milk of clinically healthy sheep and cows in the north of Palestine were determined using a polymerase chain reaction (PCR). Thirty-seven (37%) out of 100 S. aureus isolates were toxin gene positive. Four strains (10.8%) were sea-positive, 20 (54.1%) were seb-positive, 4 (10.8%) were sec-positive, 6 (16.2%) were sed-positive and 3 (8.1%) were see-positive. None of these enterotoxigenic isolates carried more than one toxin gene. This study indicates that the presence of enterotoxigenic S. aureus in raw milk can contribute to the sources of staphylococcal food poisoning in Palestine.

The antibacterial effects of single and combined plant extracts of water, ethanol and methanol for two nutraceuticals utilized in Palestine were studied against multiple drug resistances Pseudomonas aeruginosa using well diffusion method. These plants are Rhus coriaria and Thymus vulgaris. Combinations of these extracts showed an additive action against this pathogen.

Nine medicinal plants growing in Palestine were screened in vitro for potential antibacterial activity against 6 bacterial strains by well diffusion and micro-dilution techniques. Both aqueous and organic solvents were used. The dried extracts of Sacropoterium spinosum (Rosaceae) (seed), Ruta chalepensis L (Rutaceae) (leaf), Cassia senna (Ligumenosa) (leaf), Lawsonia inermis (Lythraceae) (leaf), Psidium guajava (Myrtaceae) (Leaf), Carataegus azerullus (Rosaceae) (Leaf), Ranunclus asiaticus(Ranunculaceae) (Flowers), Calendula officinalis (Composita) (Flowers),and Salvia syriaca (Labiatae) (leaf) were screened. The bacterial strains tested were; Methicillin-resistant Staphylococcus aureus (MRSA); three strains (1, 2 & 3), multidrug resistant Pseudomonas aeruginosa, Proteus vulgaris and Klebsiella pneumonia. The average diameter of inhibition zones ranged from 9 to 30 mm and 11 to 28 mm for aqueous and ethanol extract, respectively. Methicillin-resistant Staphylococcus aureus (MRSA) was the most inhibited microorganism. Sacropoterium spinosum extract was the most active against Methicillin-resistant Staphylococcus aureus (MRSA) and multidrug resistant Pseudomonas aeruginosa. The MIC value of ethanol extract was 0.781 mg/ml against MRSA while 0.390 mg/ml against Pseudomonas aeruginosa. The combination effect of ethanol extracts of (Sacropoterium spinosum with Lawsonia Inermis) on bacterial species tested exhibited a higher effect than that of any individual extract. Such results lead to an interesting promise for further investigation to design potentially active antibacterial augmentative agents of natural sources. Key words: Antibacterial activities, plant extracts, methicillin resistant Staphylococcus aureus, multi-drug resistant Pseudomonas aeruginosa, Palestine.