Biofilm formation is one of the biggest challenges of scientists. Role of heavy metals in forming biofilm is not clear enough. Here, the effect of lead on biofilm formation by Bacillus spp. isolated from soil in terms of biofilm formation and remove was studied. In present study, 10 isolates of Bacillus spp were isolated from soil. The ability of all isolates to form biofilm was evaluated. The effect of lead on biofilm formation was studied by adding lead (pb) before forming biofilm. In another experiment the lead was added after biofilm formation to study the effect of lead on biofilm remove. The current study, showed the ability of all studied isolates to form biofilm. Maximum biofilm formation by Bacillus spp isolate number 8 (B8) followed by B1 and B3. The lowest biofilm formation was found in case of isolate 4 (B4). The lead (50 ppm) reduced biofilm formation by B8, B1 and B3 isolates when the lead was used before biofilm formation (P <0.05). In another experiment the lead (50 ppm) was added after biofilm formation, it was observed that the biofilm formation was higher when the lead was added (after biofilm formation) as compared with control (serial distilled water) and the difference was significant (P<0.05). It can be concluded that the lead effect negatively on biofilm formation and positively on stability of biofilm.
Kamel, S.H., R.F. Al-Jassani and H.A. Al-Shammari. 2022. Effects of Pseudomonas fluorescens, Bacillus thuringiensis tenebrionis Isolates and Biologically Synthesized Silver Nanoparticles on Cellulase Enzyme Activity in Workers' Digestive System of the Termite Microcerotermes diversus Silv. Arab Journal of Plant Protection, 40(4): 315-324. https://doi.org/10.22268/AJPP-40.4.315324 The purpose of this study was to investigate the effect of different bacterial isolates of P. fluorescens and B. t. tenebrionis and silver nanoparticles on the activity of the cellulase enzyme in termites' middle digestive system and its role in glucose release by treating cellulose media with bacterial strains and nanoparticles. Ultraviolet spectroscopy re
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The following dilutions -710X46, -610X46, -510X46 of Bacillus thuringiensis were used for bioassay against the different larval instar of the potato tuber moth Phthorimaea operculella by the spraying method, the results showed that there was no significant influence in the percentage of egg hatching in comparison with the control. The sensitivity of larval stages was reduced with the increasing the age and exposure period. The study also showed that the larvae infected with B.t. stopped feeding, movement and a general paralysis causing the death of larva after (24-48) hours , and the larva color was changed from the natural waxy colour to brown finally to the black after death.
The following dilutions -710X46, -610X46, -510X46 of Bacillus thuringiensis were used for bioassay against the different larval instar of the potato tuber moth Phthorimaea operculella by the spraying method, the results showed that there was no significant influence in the percentage of egg hatching in comparison with the control. The sensitivity of larval stages was reduced with the increasing the age and exposure period. The study also showed that the larvae infected with B.t. stopped feeding, movement and a general paralysis causing the death of larva after (24-48) hours , and the larva color was changed from the natural waxy colour to brown finally to the black after death.
Air pollution is one of the complex problems plaguing the environment at the present time
as a result of many liberation of gases, vapors and fumes of fuels and chemicals resulting
from industrial activities . It should be noted that there are some elements of the heavy (Heavy
Metals), including toxic in the air, with different concentrations in the air depending on the
nature of the area, for example be in rural areas is lower than in cities or industrial areas as
measured parts million (ppm ) or parts per billion (ppb). Some of these important elements in
the physiological processes and enzymatic organisms but become toxic and Qatlhand-increase
Tercisahaan the permissible limits Bhave nature ,The air contaminant co
Air pollution is one of the complex problems plaguing the environment at the present time
as a result of many liberation of gases, vapors and fumes of fuels and chemicals resulting
from industrial activities . It should be noted that there are some elements of the heavy
(Heavy Metals), including toxic in the air, with different concentrations in the air depending
on the nature of the area, for example be in rural areas is lower than in cities or industrial
areas as measured parts million (ppm ) or parts per billion (ppb). Some of these important
elements in the physiological processes and enzymatic organisms but become toxic and
Qatlhand-increase Tercisahaan the permissible limits Bhave nature ,The air contaminant
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The aim of this study is to investigate the role of prodigiosin on P. aeruginosa' s biofilm genes involved in the pathogenicity and persistency of the bacteria; Materials and methods: Gram negative bacterial isolates were taken from burn and wounds specimen obtained from some of Baghdad hospitals. Forty six isolates were identified as Pseudomonas aeruginosa and four isolates as Serratia marcescens by using biochemical tests and VITEK 2 compact system. Susceptibility test was performed for all P. aeruginosa isolates, the results showed that 100% were resistant to Amikacin and 98% were sensitive to Meropenem. Resistant isolates were tested for biofilm formation; the strong and moderate isolates (17) were detected by PCR for AlgD gene
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Abstract Background: Multidrug-resistant bacteria (MDR) often contaminate hospital environment and cause serious illnesses. Quorum Sensing (QS) regulates a variety of downstream cellular processes, including antibiotics resistance mechanisms and biofilm formation, and causes harm to the host. This study investigates antibacterial susceptibility and biofilm formation of pathogenic bacteria in hospital environment. Methods: Hundred bacterial isolates were collected from various environments in the Medical City hospital. The antimicrobial susceptibility technique was evaluated through disk diffusion method. Next, biofilms formation was detected by the microliter plate assay. Finally, PCR was used to analyze the frequency of QS system gene
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