Aceh International Journal of Science and Technology
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Study on Salting out-Steam Distillation Extraction Technology and Antibacterial Activities of Essential Oil from Cumin Seeds
Get PDFThe effects of different factors on the yield of essential oil from were discussed, and the extraction conditions of essential oil from cumin seeds by salting out-steam distillation technology based on single-factor test and orthogonal experiment, as well as its antibacterial activities on several common food spoilage bacteria were studied in this paper. The results showed that, the impact order of the influence factors was liquid/solid ratio distilling time NaCl concentration, and optimized extraction conditions were as follows, liquid to material ratio 15:1, soaking time 1 h, 4% NaCl, steam distilling time 3 h. The yield of essential oil was up to 4.48% under these conditions. The results of antibacterial activity assays showed that the essential oil from cumin seeds exhibited the different antibacterial activities against some food borne pathogens, especially it presented the best inhibitory effect against Bacillus subtilis with the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 6.25 and 12.5 mg/mL respectively, followed by Staphylococcus albus and Staphylococcus aureus, the lowest for Pseudomonas aeruginosa and Shigella dysenteria
Prevalence and Antibiogram Pattern of Some Nosocomial Pathogens Isolated from Hospital Environment in Zaria, Nigeria
Get PDFMany ordinary surfaces and hands of healthcare givers in hospitals are sometimes inadequately decontaminated with routine disinfection techniques. It is necessary to determine the distribution of these pathogens in the hospitals. In this study 160 swab samples were collected from ten different surfaces including nurses hand swab, Nurses table top, door knob/handle, toilet seat, operation table, sink, stretcher, floor, bedrail, and cupboard. Biochemical tests were used to identify the bacteria. Kirby-Bauer-Clinical and Laboratory Standards Institute (CLSI) modified single disc diffusion technique was used to determine the antibiogram profile of the pathogens at 0.5 scale McFarlands standard (1.5 108 cells/ml). The total percentage prevalence of Staphylococcus aureus was 50.80%, Pseudomonas aeruginosa 28.60% and Escherichia coli 20.60%. Out of 20.60% of E. coli isolates7.7% were found to be E. coli O157:H7. S. aureus isolates were highly resistant to ampcillin and cefoxitin P. aeruginosa and E. coli were resistant to tetracycline. The multiple antibiotic resistance indexes of the pathogens were more than 0.2. Among the isolates, S. aureus showed more multidrug resistance (31.30%) and E. coli had the least multidrug. Frequently touched surfaces within the hospital environment are contaminated by Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus. These pathogens can be transfer from surfaces to patients and to surfaces again through healthcare workers. The widespread use of antimicrobials, especially over- or inappropriate use of antibiotics, has contributed to an increased incidence of antimicrobial-resistant organisms
The Effect of Rainfall Patterns on the Mechanisms of Shallow Slope Failure
Get PDFAbstract - This paper examines how rainfall patterns affect the mechanisms of shallow slope failure. Numerical modelling, utilising the commercial software SVFlux and SVSlope, was carried out for a coupled analysis of rainfall-induced slope seepage and instability, with reference to a shallow landslide took place in Jabiru, Northern Territory (NT) Australia in 2007. Rainfall events were varied in terms of pattern in this analysis. The results revealed that slopes are sensitive to rainfall pattern when the rainfall intensity has a high degree of fluctuation at around the same value as that of saturated hydraulic conductivity. Average rainfall intensity at the beginning of a rainfall period plays a primary role in determining the rate of decrease in initial factor of safety (Fi) towards minimum factor of safety (Fmin). The effect of rainfall events on the slope instability is attributed to the amount of rainwater infiltration into slope associated with rainfall pattern.Keywords: Rainfall pattern; Fluctuating intensity, Shallow failure mechanism; Slope failure; Rainwater infiltration
Study on The Potency of Methanol Extracts From Xanthosoma nigrum Stellfeld As Natural Anti Oxidant by Thiobarbituric Acid Method
Get PDFAbstract- In this research Xanthosoma nigrum Stellfeld (the Purple yam) was selected as experimental material. This plant was collected from Rejang Lebong region, Bengkulu Province. Methanol extract 96% from stem of purple yam was studied its anti-oxidant activity in various concentrations with -tocopherol (200 ppm) as standard of antioxidant. Antioxidant activity was determined using Thiobarbituric Acid (TBA) method. Linoleic acid was oxidized at 40 C for seven days with or without extract and the final product malondialdehyde (MDA) was reacted with thiostembituric acid to be of red colored complex (MDA-TBA) and was then measured by UV-VIS spectrophotometer at 532 nm. Stem extract of purple yam with concentration of 100 ppm, 150 ppm, 200 ppm and 300 ppm respectively had the inhibition of 19.32%, 21.85%, 29.47%, and 31.05%. -Tocopherol as positive control which showed inhibition ability of 85.14% at 200 ppm. Based on the result obtained in this study, the stems extract of Purpel yam plant showed that antioxidant activity was lower than -tocopherol.Keywords : Xanthosoma nigrum; Stellfeld; MDA; Antioxidant
Effectiveness of the Vietnamese Good Agricultural Practice (VietGAP) on plant growth and quality of Choy Sum (Brassica rapa var. Parachinensis) in Northern Vietnam
Get PDFIn response to the recent concerns about human health, ecosystem sustainability and thus demands for food safety, production of clean produce, particularly daily-consumed vegetables, is essential. The study was carried out in Thai Nguyen city (northern Vietnam) during August November 2011 to evaluate impacts of a VietGAP guideline on plant growth and quality of Choy Sum, one of the major vegetables in the research area. The experiment comprised two treatments, a control (local farmers conventional practice) and an experimental treatment (plants grown according to the VietGAP guideline). Plant samples of the latter treatment were collected for quality test at the end of the experiment. Results showed that the experimental plants had significant higher growth parameters with regards to leaf areas (7.13 dm2) and average top plant weight (3.33 kg m-2), while those of the control treatment were 5.80 dm2 and 2.77 kg m-2, respectively. Lab test results showed the experimental plant samples met the national quality standards to be certified as a clean product. The participatory on-field experiment would facilitate critical reflections, transformative learning and readiness for adoption of eco-friendly production practices by the local farmer
Phytochemical Screening and In Vitro Antibacterial Activity of Methanol and Aqueous Extracts of Acalypha Racemosa Leaves
Get PDFAbstract - Drug resistance microorganisms have posed enormous public concern there is therefore a need to screen plants that could have the potency in the control of the pathogenic organisms. The extracts obtained from the Acalypha racemosa were screened for phytochemical properties and in vitro investigation of methanol and aqueous extracts. The phytochemical screening revealed the presence of saponins, phlabatanins, flavonoids, and alkaloids. Glycoside and cardiac glycoside, tannins and sterols were in traced amount. The in vitro antibacterial investigation of the crude extract was conducted. The studies showed that the plant contains compounds that have antibacterial activity. The extracts revealed greater potential against the test bacteria with zones of inhibition ranging from 20-30 mm for methanol extract in the order Escherichia coliKlebsiella pneumoniaeProteus mirabilisBacillus subtilisPseudomonas aeruginosa and 18-27mm for aqueous extract in the order Escherichia coli Bacillus subtilis Klebsiella pneumoniae and Pseudomonas aeruginosa Proteus mirabilis. All the bacteria were more susceptible to methanol extract than the aqueous extract as indicated in the zones of inhibition with exception of Pseudomonas aeruginosa in which there was no inhibition. The aqueous extract had effect on all the test bacteria although having zones of inhibition lower than the methanol extract. The minimum inhibitory concentration (MIC) of both extracts range from 12.5-50 mg/ml and the minimum bactericidal concentration (MBC) range from 25-100 mg/ml. Escherichia coli was more susceptibility to both extracts and less was seen in the case of aqueous extract against Proteus mirabilis. The screening of the plant has revealed its potency in the treatment of pathogenic infections that may be caused by these pathogens
Changes in Physicochemical Properties of Soil Encourage the Invasion Establishment and Carbon Dynamics of Lantana camara from Doon Valley, Western Himalaya, India
Get PDFAbstract - Lantana camara L. is a recognized weed of worldwide significance due to its widespread distribution and impacts on nature conservation. In this study physicochemical properties of soil were analysed from different high and low Lantana infested areas. Significant site effect was frequently observed than effect due to invasion status. The present study tested the impact of soil properties in the measured and calculated attributes of Lantana by randomly sampling soil from the highly invaded and less invaded sites in different habitats using the Modified Whittaker plot design. Ten samples were collected at high invaded and ten at less invaded sites per habitat totalling to 120 which were obtained and analysed. One way analysis of variance (ANOVA) results indicated that edaphic factors such as soil pH, total nitrogen, soil organic carbon, Phosphorus and Potassium content positively influenced the growth of Lantana and helped in the further invasion process. These factors were also positively influencing the measured and calculated attributes of Lantana such as canopy coverage, average crown diameter, shrub canopy area, phytovolume and biomass from all sites. However some attributes like shrub height and stem diameter were negatively influenced by these soil factors. The level of these soil nutrients was found elevated in all Lantana invaded sites as compared to less invaded sites. The present results reveal that Lantana invasion can not only significantly improve the soil nutrient level but also positively increase the chances of its further invasion with more copious plant attributes
Isolation and Identification of Air Borne Fungal Spores and Fragments in Buildings within Usmanu Danfodiyo University Sokoto, Nigeria
Get PDFAbstract - Indoor air contains a complex mixture of microorganisms, microorganism fragments, and by products such as molds, bacteria, endotoxins, mycotoxins, and volatile microbial organic compounds. Airborne fungi and bacteria can be toxic, allergenic and/or infectious. A research was conducted to determine the number and types of airborne fungal spores in Buildings of Usmanu Danfodiyo University Sokoto, Nigeria. Five (5) areas were chosen within the University for the Survey, these were student Hostel, Staff Quarters, Botanical garden, Microbiology laboratory and city campus of Usmanu Danfodiyo University. . A total number of fifteen (15) petri dishes containing potato dextrose agar each were vertically placed in each sampler and exposed at end of each height and site for 10 and 20 minutes respectively. A total of thirteen (13) different fungal specie were identified namely; Aspergillus niger, A. flavus, A fumigates, A. ustus, A. terreus, Fusarium solani, F. oxysporum, Alterneria altenata, Rhizopus oryzae, R. stolonifer, Helminthosporum sp., Penicillum candidum and Absedia corymbifera. Aspergillus niger had the highest frequency of occurrence of (14.9%), Helminthosporus species had the least frequency of occurrence of (1.5%). Conclusively it was observed that the concentration of fungal spores was high in the upper surface than the ground level at the time of the survey
A Preliminary Study on Microbial Contamination of Leafy Vegetables in Sokoto Metropolis, Nigeria
Get PDFFive leafy vegetables commonly consumed in Sokoto metropolis were evaluated for microbiological quality using standard procedures involving standard plate count (SPC). The vegetables investigated included Lactuaca sativa (Lettuce), Amaranthus hybridus (Spinach), Vernonia amagdalina (Bitter leaf), Brassica oleracea (Cabbage) and Moringa oleifera Lam (Horse radish). Ten fungal species which include Alternaria alternata, Absidia corymbifera, Aspergillus niger, A. flavus, Cladosporium herbarum, Fusarium oxysporium, Geotrichum candidum, Mucor racemoses, Rhizopus stolonifer and Trichoderma harzianum and four species of bacteria: Bacillus cereus, Escherichia coli, Listeria monocystogens and Staphyllococus aureus were isolated from the leafy vegetables. The total colony counts of fungi ranged from 1.8 x 106 6.28 x 105 (cfu/g) of the vegetables while that of bacteria ranged from 1.0 x 106 to 2.94 x 106 cfu/g of the vegetables. The highest counts of microbial organisms were found on A. hybridus while M. oleifera and B. olerarea had the lowest fungal and bacterial counts respectively. There is a need to reduce the levels of microbial contamination on leafy vegetables through appropriate production practices, careful handling by the vendors and appropriate processing with a view to minimize the risk of human exposure to fungal and bacterial pathogens associated with the vegetables
DFT and PM3 Computational Studies of the Reaction Mechanism of the Oxidation of L-Tyrosine by Iodine in the Gas Phase
Get PDFAbstract - The oxidation of L-Tyrosine by molecular iodine was studied using semi-empirical and density functional theory methods. Molecular information such as net charges, values of frontier orbital energies, composition, proportions and bonding contribution were obtained and analyzed. Thus, possible reactive sites were proposed and the reaction mechanism was postulated. The postulated transition states, intermediates and products were also computed using the PM3 and DFT methods. Computed enthalpies of the oxidation reaction at standard conditions for the PM3 and DFT calculation were216.97 kJ/mol and -36327404.72 kJ/mol respectively. The calculated Go andSo, for the transition states according to the DFT model were both large and negative indicating that the processes were exergonic associative substitution reactions