Objective:To evaluate the antimicrobial activity of methanolic extracts of six marine macroalgae belonging to green algae(Chlorophyceae),brown algae(Phaeophyceae)and the red algae(Rhodophyceae)collected from the inter...Objective:To evaluate the antimicrobial activity of methanolic extracts of six marine macroalgae belonging to green algae(Chlorophyceae),brown algae(Phaeophyceae)and the red algae(Rhodophyceae)collected from the intertidal area of the Sudanese Red Sea coast near Port Sudan.Methods:Methanol was used for extracting the active principles of the algae and the disc diffusion method was performed to examine the activity and the minimum inhibitory concentration of the samples against four pathogenic bacteria and two fungi.Results:All tested algal extracts exhibited considerable bioactivity and inhibited the growth of all pathogenic microorganisms under investigation.The green alga Caulerpa racemosa produced the maximum inhibition zone(21 mm)against Candida albicans while the red alga Laurencia papillosa showed low antimicrobial activity with the minimum inhibition zone of 10 mm against Pseudomonas aeruginosa.The tested algal extracts did not show any special antimicrobial influence on the selected microorganisms when they were considered as Grampositive and Gram-negative bacteria and fungi but the most efficient methanolic extracts in inhibiting microbial growth were those of green macroalgae followed by the brown and the red macroalgae respectively.Conclusions:The study demonstrated that the tested marine macroalgae from Sudanese Red Sea coast may represent a potential and alternative source for secondary metabolites with antimicrobial activity.展开更多
In this study, the optimum operating conditions for sesame oil extraction were studied. N-hexane was used as a solvent. Different variables were investigated;sesame seeds particle sizes, ratio of solvent to seeds mass...In this study, the optimum operating conditions for sesame oil extraction were studied. N-hexane was used as a solvent. Different variables were investigated;sesame seeds particle sizes, ratio of solvent to seeds mass, contact time, stirring effect, roasting impact and extraction temperatures. Results obtained showed that higher rates of extraction were obtained when roasting sesame seed to 15℃. The ratio of solvent to seeds found to be 6:1 gave higher extraction. Moreover, stirring speed was tested and had been optimized to 600 rpm. Finally, the extraction under heating was studied and results showed that increasing operating temperature to more than 40℃ did not increase extraction efficiency.展开更多
Many lactic acid bacteria (LAB) were isolated from “Shermout”, a popular Sudanese fermented beef product intended for long storage. An isolate that demonstrated significant antibacterial activity was identified as L...Many lactic acid bacteria (LAB) were isolated from “Shermout”, a popular Sudanese fermented beef product intended for long storage. An isolate that demonstrated significant antibacterial activity was identified as Lactobacillus plantarum PM4 based on phenotypic, physiological and biochemical characteristics and carbohydrate utilization patterns. The inhibitory activity of the partially purified bacteriocin was completely arrested by the proteolytic enzymes proteinase-k and pepsin but not by α-amylase, asserting its proteinaceous nature. The activity was not due to H2O2 as similar inhibition was obtained by cell-free supernatant (CFS) produced under anaerobic conditions. The bacteriocin showed a molecular weight in the range of 3 - 5 kDa and had a bactericidal mode of action. No significant reduction in activity was observed on heating to 60℃ for 60 min, but activity was lost on heating to 100℃ or autoclaving. Highest inhibitory activity was at pH 5.5 and there was appreciable reduction in activity at pH 3, 7 or 9. There was no drop in activity at –80℃ or –20℃ up to four weeks of storage. However, at 4℃ and 35℃, a gradual decline in activity was observed. Lb. plantarum PM4 exhibited bactericidal activity against Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, Escherichia coli ATCC25922, Klebsiella pneumoniae and Proteus vulgaris. Bacteriocin production generally coincided with the phase of maximum growth and the best combination for maximum production of inhibitory activity was at pH 5.5 for 48 h whether incubated at 25℃, 30℃ or 37℃. Lb. plantarum PM4 showed promise as a starter culture in the fermentation of preserved meat products.展开更多
Objective:Various nail disorders have been reported in patients with chronic kidney disease.However,few studies have investigated nail disorders in patients with advanced chronic kidney disease.This study focused on n...Objective:Various nail disorders have been reported in patients with chronic kidney disease.However,few studies have investigated nail disorders in patients with advanced chronic kidney disease.This study focused on nail disorders seen in patients with end-stage renal disease(ESRD)undergoing conservative treatment.Methods:A case-control study was conducted at Baraha Medical City in Khartoum State,Sudan.Data on patients with ESRD who were on conservative treatment and presented for follow-up between March and September 2021 were collected.Patients’demographic features,nail findings on clinical examination,and laboratory results were recorded.The obtained data were compared with those on age-and sex-matched healthy individuals from the general population.The chi-square test and Student t test were performed to analyze categorical and numerical variables,respectively.Results:Data on 78 patients with ESRD were studied.Their mean age was 54.6±17.6 years,and 45(57.7%)were men.These patients were compared with 129 controls.Nail disorders were seen in 65(83.3%)ESRD patients and 86(66.6%)controls(P=0.009).Patients with ESRD were found to be at increased relative risk of developing a wide spectrum of nail disorders.An absent lunula,half-and-half nails,nail dystrophy,Terry’s nails,onychomycosis,and koilonychia were the most common disorders and were seen in 44(56.4%),13(16.7%),10(12.8%),9(11.5%),6(7.7%),and 5(6.4%)patients,respectively.Patients with ESRD had a statistically significant risk of developing above diseases(all P<0.05).Conclusion:The current study demonstrated a wide spectrum of nail disorders in patients with ESRD undergoing conservative treatment.Further studies are essential to understand their pathogenesis.展开更多
基金Supported by the grant(RSU\1\2013)of the Red Sea University.
文摘Objective:To evaluate the antimicrobial activity of methanolic extracts of six marine macroalgae belonging to green algae(Chlorophyceae),brown algae(Phaeophyceae)and the red algae(Rhodophyceae)collected from the intertidal area of the Sudanese Red Sea coast near Port Sudan.Methods:Methanol was used for extracting the active principles of the algae and the disc diffusion method was performed to examine the activity and the minimum inhibitory concentration of the samples against four pathogenic bacteria and two fungi.Results:All tested algal extracts exhibited considerable bioactivity and inhibited the growth of all pathogenic microorganisms under investigation.The green alga Caulerpa racemosa produced the maximum inhibition zone(21 mm)against Candida albicans while the red alga Laurencia papillosa showed low antimicrobial activity with the minimum inhibition zone of 10 mm against Pseudomonas aeruginosa.The tested algal extracts did not show any special antimicrobial influence on the selected microorganisms when they were considered as Grampositive and Gram-negative bacteria and fungi but the most efficient methanolic extracts in inhibiting microbial growth were those of green macroalgae followed by the brown and the red macroalgae respectively.Conclusions:The study demonstrated that the tested marine macroalgae from Sudanese Red Sea coast may represent a potential and alternative source for secondary metabolites with antimicrobial activity.
文摘In this study, the optimum operating conditions for sesame oil extraction were studied. N-hexane was used as a solvent. Different variables were investigated;sesame seeds particle sizes, ratio of solvent to seeds mass, contact time, stirring effect, roasting impact and extraction temperatures. Results obtained showed that higher rates of extraction were obtained when roasting sesame seed to 15℃. The ratio of solvent to seeds found to be 6:1 gave higher extraction. Moreover, stirring speed was tested and had been optimized to 600 rpm. Finally, the extraction under heating was studied and results showed that increasing operating temperature to more than 40℃ did not increase extraction efficiency.
文摘Many lactic acid bacteria (LAB) were isolated from “Shermout”, a popular Sudanese fermented beef product intended for long storage. An isolate that demonstrated significant antibacterial activity was identified as Lactobacillus plantarum PM4 based on phenotypic, physiological and biochemical characteristics and carbohydrate utilization patterns. The inhibitory activity of the partially purified bacteriocin was completely arrested by the proteolytic enzymes proteinase-k and pepsin but not by α-amylase, asserting its proteinaceous nature. The activity was not due to H2O2 as similar inhibition was obtained by cell-free supernatant (CFS) produced under anaerobic conditions. The bacteriocin showed a molecular weight in the range of 3 - 5 kDa and had a bactericidal mode of action. No significant reduction in activity was observed on heating to 60℃ for 60 min, but activity was lost on heating to 100℃ or autoclaving. Highest inhibitory activity was at pH 5.5 and there was appreciable reduction in activity at pH 3, 7 or 9. There was no drop in activity at –80℃ or –20℃ up to four weeks of storage. However, at 4℃ and 35℃, a gradual decline in activity was observed. Lb. plantarum PM4 exhibited bactericidal activity against Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, Escherichia coli ATCC25922, Klebsiella pneumoniae and Proteus vulgaris. Bacteriocin production generally coincided with the phase of maximum growth and the best combination for maximum production of inhibitory activity was at pH 5.5 for 48 h whether incubated at 25℃, 30℃ or 37℃. Lb. plantarum PM4 showed promise as a starter culture in the fermentation of preserved meat products.
文摘Objective:Various nail disorders have been reported in patients with chronic kidney disease.However,few studies have investigated nail disorders in patients with advanced chronic kidney disease.This study focused on nail disorders seen in patients with end-stage renal disease(ESRD)undergoing conservative treatment.Methods:A case-control study was conducted at Baraha Medical City in Khartoum State,Sudan.Data on patients with ESRD who were on conservative treatment and presented for follow-up between March and September 2021 were collected.Patients’demographic features,nail findings on clinical examination,and laboratory results were recorded.The obtained data were compared with those on age-and sex-matched healthy individuals from the general population.The chi-square test and Student t test were performed to analyze categorical and numerical variables,respectively.Results:Data on 78 patients with ESRD were studied.Their mean age was 54.6±17.6 years,and 45(57.7%)were men.These patients were compared with 129 controls.Nail disorders were seen in 65(83.3%)ESRD patients and 86(66.6%)controls(P=0.009).Patients with ESRD were found to be at increased relative risk of developing a wide spectrum of nail disorders.An absent lunula,half-and-half nails,nail dystrophy,Terry’s nails,onychomycosis,and koilonychia were the most common disorders and were seen in 44(56.4%),13(16.7%),10(12.8%),9(11.5%),6(7.7%),and 5(6.4%)patients,respectively.Patients with ESRD had a statistically significant risk of developing above diseases(all P<0.05).Conclusion:The current study demonstrated a wide spectrum of nail disorders in patients with ESRD undergoing conservative treatment.Further studies are essential to understand their pathogenesis.
