Comparative study on mitogen activated protein kinase of Plasmodium species by using in silico method / Mohd Fakharul Zaman Raja Yahya and Hasidah Mohd Sidek

Malaria parasites, Plasmodium can infect a wide range of hosts including humans and rodents. There are two copies of mitogen activated protein kinases (MAPKs) in Plasmodium, namely MAPK1 and MAPK2. The MAPKs have been studied extensively in the human Plasmodium, P. falciparum. However, the MAPKs from other Plasmodium species have not been characterized and it is therefore the premise of presented study to characterize the MAPKs from other Plasmodium species-P. vivax, P. knowlesi, P. berghei, P. chabaudi and P.yoelli using a series of publicly available bioinformatic tools. In silico data indicates that all Plasmodium MAPKs are nuclear-localizedandcontain both a nuclear localization signal (NLS) anda Leucine-rich nuclear export signal (NES). The activation motifs ofTDYand TSH werefound to befully conserved in Plasmodium MAPK1 and MAPK2, respectively

Influence of fresh and thermoxidized carotino oil on Cyclic Guanosine Monophosphate (cGMP) in erythrocytes from Sprague dawley rats / Mohd Fakharul Zaman Raja Yahya and Athifah Najwani Shahidan

Cyclic guanosine monophosphate (cGMP) is a second messenger molecule involved in the intracellular signalling mechanism which is important in a wide range of cellular process including metabolism, gene expression, cell proliferation and cell death. This study was conducted to determine the effect of fresh (FCO) and thermoxidized carotino oil (TCO) on erythrocyte cGMP levels from Sprague dawley rats. A total of 30 Sprague dawley rats were randomly segregated into three groups: the first of which was placed on a Fresh Carotino Oil (FCO) diet, the second on a Thermoxidized Carotino Oil (TCO) diet and the control group on commercial rat chow only for a period of 6 and 9 weeks. The two oil diets comprised of 20% (w:w) of each oil mixed with commercial rat feed. The enzyme immunoassays, performed in week 6, revealed that the erythrocytes cGMP levels for the FCO and TCO groups were 66.198±3.193 pmol/mL and 61.990±6.318 pmol/mL respectively, and were significantly (p<0.05) lower than the value for the control group, 77.978±10.479 pmol/mL. The assays performed in week 9 revealed the erythrocytes cGMP levels for the FCO and TCO groups to be 66.522±8.194 pmol/mL and 56.842±8.546 pmol/mL respectively which were also significantly (p<0.05) lower than that for the control group, 82.817±6.677 pmol/mL. The results indicate that the presence of antioxidants, such as beta-carotene and tocols in carotino oil may modulate cGMP levels in rats

Effects of erythromycin, nystatin and their combination on Pseudomonas aeruginosa and Candida albicans biofilms

Introduction: Pseudomonas aeruginosa is frequently found to coexist and interact with Candida albicans in the polymicrobial biofilms. Considering the pathogenicity of polymicrobial biofilms in many persistent infections, this study was aimed to evaluate the combined effects of antibiotics erythromycin and nystatin on P. aeruginosa-C. albicans polymicrobial biofilm under both aerobic and anaerobic conditions. Methods and Results: Treatment with single (erythromycin or nystatin) and combined antibiotics caused subtle reductions in the number of viable biofilm cells as well as protein and extracellular DNA content of the biofilm extracellular polymeric substance (EPS). Protein profiling demonstrated differential expression of biofilm proteins following exposure to the antimicrobial treatments. Conclusion: These findings suggest that erythromycin and nystatin, either single or in combination affect EPS composition (protein and extracellular DNA) as well as biofilm protein expression

FTIR spectroscopic study of inhibition of chloroxylenol-based disinfectant against salmonella enterica serovar thyphimurium biofilm

The present work was performed to determine the impacts of commercial disinfectants against biomass, viability, and biochemical composition of Salmonella enterica serovar Thyphimurium ATCC14028 biofilm. Salmonella Thyphimurium biofilm grown in microplates was exposed to commercial disinfectants namely sodium hypochlorite, benzalkonium chloride, chloroxylenol, and sodium dodecyl-benzene sulfonate-based disinfectants. Biofilm biomass, biofilm viability, and biochemical composition of the biofilm were determined using crystal violet assay, resazurin assay and Fourier transform infrared (FTIR) spectroscopy respectively. Results demonstrated that, among four commercial disinfectants, chloroxylenol-based disinfectant showed the highest inhibition against S. Thyphimurium biofilm. It remarkably hindered biofilm biomass and biofilm viability at all tested concentrations (0.78%-25%). Half-maximal biofilm inhibitory concentration (BIC50) of chloroxylenol-based disinfectant (5.06%) was found to be the lowest among the tested disinfectants. Meanwhile, S. Thyphimurium biofilm treated with chloroxylenol-based disinfectant exhibited changes in FTIR spectral peaks associated with lipid (1460 cm-1), protein (630 cm-1, 702 cm-1, 1550 cm-1 & 1650 cm-1), and nucleic acid (1080 cm-1 & 1229 cm-1). The findings of the present study suggest that the inhibition of chloroxylenol-based disinfectant against S. Thyphimurium biofilm is mediated by structural changes of biofilm

Genotoxicity and cytotoxicity evaluation of sea cucumber (Stichopus horrens) protein hydrolysates

Sea cucumber (Stichopus horrens) protein hydrolysates were known as a potential functional food source with angiotensinconverting enzyme (ACE) inhibitory. The genotoxicity properties of S. horrens protein hydrolysates have been investigated through two different in vitro tests: Ames test and in vitro micronucleus test while the cytotoxicity properties of S. horrens protein hydrolysate were assessed using neutral red test. The study was conducted at a concentration up to 8000 μg/ml, 80 μg/ml and 50 μg/ml for Ames test, in vitro micronucleus test and neutral red test respectively with and without metabolic activation. There were no increments in the number of revertant colonies observed at any concentrations of S. horrens protein hydrolysates with and without metabolic activation in all four strains of Salmonella typhimurium (TA98, TA100, TA1535 and TA1537) compared to the solvent control. In in vitro micronucleus test, S. horrens protein hydrolysate did not induce clastogenicity in V79 cell while in neutral red test, S. horrens protein hydrolysate did not show any cytotoxic effects on NIH/3T3 mouse fibroblast cell. In conclusion, S. horrens protein hydrolysates are safe in terms of genotoxic and cytotoxic hence have the potential to be used in pharmaceutical and food industries as functional ingredient

Methanolic extract of swietenia macrophylla exhibits antibacterial and antibiofilm efficacy against gram-positive pathogens

Gram-positive pathogens cause infections such as pneumonia, skin infections, anthrax, and sinusitis. The objective of this study was to determine the phytochemical profile, antibacterial and antibiofilm efficacy of Swietenia macrophylla methanolic extract (SMME) against Gram-positive pathogens. The secondary metabolites of SMME were analyzed using GC-MS while the antibacterial efficacy of SMME against Staphylococcus aureus ATCC 33862, Bacillus cereus ATCC 11778, Streptococcus pneumonia ATCC 19615, and Clostridium sporogenes ATCC 13124 was assessed using MIC and MBC assays. Biofilm biomass assay and time-kill assay were performed to determine the antibiofilm activity of SMME against the pathogens. Results demonstrated that six common antibacterial secondary metabolites were present in the SMME. The major compound was found to be β-amyrin (22.8%). The SMME showed the lowest MIC values against B. cereus (31.25 μg/mL) and C. sporogenes (31.25 μg/mL) and the lowest MBC value against S. aureus (1000 μg/mL). The SMME also significantly (p<0.05) inhibited all the biofilms. It started to inhibit S. pneumonia and C. sporogenes biofilms after 12 h of exposure. On the other hand, the BIC50 value showed that the SMME was most effective against B. cereus. In conclusion, the secondary metabolites in the SMME may contribute to the antibacterial and antibiofilm efficacy against Gram-positive pathogens

Antibacterial and antibiofilm activities of Swietenia macrophylla king ethanolic extract against foodborne pathogens

Swietenia macrophylla is known to possess several medicinal uses, however, its antibacterial and antibiofilm activities against foodborne pathogens remain not well investigated. The present work was performed to examine the phytochemical compounds, antibacterial and antibiofilm activities of S. macrophylla ethanolic extract (SMEE) against four foodborne pathogens namely, Salmonella typhimurium ATCC 14028, Escherichia coli ATCC 25922, Shigella sonnei ATCC 33862 and Pseudomonas aeruginosa ATCC 10145. The phytochemical analysis of SMEE was performed using gas chromatography-mass spectrometry while the antibacterial activities of SMEE were determined by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. On the other hand, the antibiofilm and time-killing activities of SMME were evaluated using a crystal violet assay. The result demonstrated that SMEE contained major phytochemical compounds such as olean-12-ene (27.37%), resorcinol (16.45%), 24-noroleana-3,12-diene (13.4%), and germanicol (11.50%). The MIC values of SMEE ranged from 31.25 to 500 μg/mL, while all the MBC values were found to be greater than 1000 μg/mL. At the 12 h exposure to SMEE, all the biofilms were inhibited by 50% except E. coli. Biofilm inhibitory concentration (BIC50) values of SMEE ranged between 5.19 and 42.47 μg/mL. In conclusion, S. macrophylla is a promising source of natural antibacterial and antibiofilm agents to treat foodborne diseases

Antibacterial and antibiofilm activities of Swietenia macrophylla king ethanolic extract against foodborne pathogens

Swietenia macrophylla is known to possess several medicinal uses, however, its antibacterial and antibiofilm activities against foodborne pathogens remain not well investigated. The present work was performed to examine the phytochemical compounds, antibacterial and antibiofilm activities of S. macrophylla ethanolic extract (SMEE) against four foodborne pathogens namely, Salmonella typhimurium ATCC 14028, Escherichia coli ATCC 25922, Shigella sonnei ATCC 33862 and Pseudomonas aeruginosa ATCC 10145. The phytochemical analysis of SMEE was performed using gas chromatography-mass spectrometry while the antibacterial activities of SMEE were determined by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. On the other hand, the antibiofilm and time-killing activities of SMME were evaluated using a crystal violet assay. The result demonstrated that SMEE contained major phytochemical compounds such as olean-12-ene (27.37%), resorcinol (16.45%), 24-noroleana-3,12-diene (13.4%), and germanicol (11.50%). The MIC values of SMEE ranged from 31.25 to 500 μg/mL, while all the MBC values were found to be greater than 1000 μg/mL. At the 12 h exposure to SMEE, all the biofilms were inhibited by 50% except E. coli. Biofilm inhibitory concentration (BIC50) values of SMEE ranged between 5.19 and 42.47 μg/mL. In conclusion, S. macrophylla is a promising source of natural antibacterial and antibiofilm agents to treat foodborne diseases

FTIR spectral changes in Candida albicans biofilm following exposure to antifungals

Candida albicans is a microbial fungus that exists as a commensal member of the human microbiome and an opportunistic pathogen. Biofilm formation by this fungal pathogen occurs mostly in the mucosa or endothelium associated with candidiasis and colonizes medical devices. The present work was performed to determine the efficacy of the antifungal creams on the viability and biochemical composition of C. albicans biofilm. Four commercial antifungal creams were used herein namely econazole nitrate, miconazole nitrate, ketoconazole and tolnaftate. Resazurin assay and Fourier transform infrared (FTIR) spectroscopy were performed to determine the viability and biochemical composition of C. albicans biofilm, respectively. Results demonstrated that the antifungal creams inhibited C. albicans biofilm. The highest percent inhibition shown by econazole nitrate, miconazole nitrate, ketoconazole, and tolnaftate were 16.5%, 17.1%, 15.8%, and 6.9%, respectively. Econazole nitrate with the lowest IC50 value of 43.42 μg/mL caused changes in the FTIR spectral peak shape at 1377 cm-1 and 1736 cm-1. On the other hand, miconazole nitrate with the second lowest IC50 value of 118.26 μg/mL caused spectral peak shifting from 1237 cm-1 to 1228 cm-1. In conclusion, the inhibition of C. albicans biofilm may be mediated by the changes in protein, lipid, and nucleic acid compositions