scholarly journals A Quantitative Determination of the Antibacterial Efficiency of Fibrous Air Filters Based on the Disc Diffusion Method

2014 ◽  
Vol 14 (3) ◽  
pp. 928-933 ◽  
Author(s):  
Yun Haeng Joe ◽  
Wei Ju ◽  
Ji Hye An ◽  
Jungho Hwang
Author(s):  
Daniel A. Ondeko ◽  
Bernard F. Juma ◽  
Lilechi D. Baraza ◽  
Peter K. Nyongesa

Aims: To determine chemical constituents of the Leaf extracts of Centella asiatica using the LC-MS and GC-MS and their antimicrobial activities. Study Design: Structural determination of compounds from the leaf extracts was done using GC-MS and LC-MS analysis. The antimicrobial properties of the extracts were done using disc diffusion method. Place and Duration of Study:  Pure and Applied Chemistry Department, Masinde Muliro University of Science and Technology, Kenya: Between 2016-2019. Methodology: Plant materials of C. asiatica were sequentially extracted separately based on the polarity viz., hexane, ethyl acetate and methanol. Determination of chemical constituents was done using LC-MS and GC-MS analysis and phytochemical screening. The extracts were assayed against Staphylococcus aureus, Klebsiella pneumonia, Escherichia coli and Candida albicans. Standard antimicrobials viz. ampicillin and Nystatin were used as the control. Disc diffusion method was used and zones of inhibition, after respective incubation periods, were used to quantify antibacterial and antifungal activity. Results: Phytochemical screening of the hexane, ethyl acetate and methanolic extracts showed that terpenoids, flavonoids, saponins, alkaloids, steroids, amino acids and proteins, reducing sugars and carbohydrates were present. LC-MS and GC-MS analyses of the methanolic extracts identified 22 and 33 compounds, respectively, by use of the national institute of standards and technology (NIST) library. The extracts showed appreciable activity against common microbes tested. Conclusion: This study forms the basis for the biological characterization and significance of the compounds identified in the leaf and stem extracts of C. asiatica. These compounds are known to possess antibacterial and antifungal activities that could be established as potential candidates for future drug development. However, these extracts, need to be subjected to further chromatographic procedures to isolate the identified compounds and their bioactivities determined.


2011 ◽  
Vol 2011 ◽  
pp. 1-4 ◽  
Author(s):  
A. Arul Prakash ◽  
S. Balasubramanian ◽  
G. Gunasekaran ◽  
M. Prakash ◽  
P. Senthil Raja

In the present study, effort has been made to find the antimicrobial activity of haemolymph collected from freshwater crab, Paratelphusa hydrodromous. The haemolymph collected was tested for antimicrobial assay by disc diffusion method against clinical pathogens. Five bacterial species, namely, Escherichia coli, Klebsiella pneumonia, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus, and five fungal strains, namely and Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Rhizopus sp., and Mucor sp., were selected for the study. The result shows a strong response of haemolymph against the clinical pathogens which confirms the immune mechanism of the freshwater crab.


2021 ◽  
Vol 37 (2) ◽  
pp. 54-64
Author(s):  
D.V. Barabash ◽  
I.A. Butorova

The possibility of using simple and available methods for analyzing deodorants/antiperspirants has been studied. The gravimetric method was shown to have acceptable metrological characteristics under repeatability conditions when evaluating antiperspirant activity. A decrease in the number of microorganisms (CFU) on the axilla skin was observed in a rinse test experiment 4 h and 8 h after the application of deodorants/antiperspirants. The microbial population data were inversely proportional to the antiperspirant activity values of the tested compositions. The sweat secretion reducing decreases the amount of nutrients required for microbial development, which makes it possible to use the rinse test to indirectly evaluate deodorant activity in research and development of personal care products. However, due to its laboriousness and the need for volunteers, the method cannot be recommended for large-scale testing. It was shown that the disc diffusion method (DDM) used to detect Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus subtilis cannot be applied to the assessment of the intrinsic antimicrobial activity of the tested cosmetic compositions. This indicates the necessity of additional studies to select test microorganisms typical for the armpit area. In addition, DDM is useful if the deodorant effect of the composition is created by the addition of low-volatile antibacterial compounds. Therefore, microbiological methods have limited applications and are not suitable for widespread use. deodorant action; antiperspirant action, gravimetry, disc diffusion method, rinse test; deodorant; antiperspirant; cosmetic; efficiency; consumer properties, functional properties This work was supported by MUCTR (project no. K-2020-007).


10.5219/1695 ◽  
2021 ◽  
Vol 15 ◽  
pp. 1112-1119
Author(s):  
Hana Ďúranová ◽  
Veronika Valková ◽  
Lucia Galovičová ◽  
Jana Štefániková ◽  
Miroslava Kačániová

Fungal food spoilage plays a key role in the deterioration of food products, and finding a suitable natural preservative can solve this problem. Therefore, antifungal activity of green mandarin (Citrus reticulata) essential oil (GMEO) in the vapor phase against the growth of Penicillium (P.) expansum and P. chrysogenum inoculated on wheat bread (in situ experiment) was investigated in the current research. The volatile compounds of the GMEO were analyzed by a gas chromatograph coupled to a mass spectrometer (GC–MS), and its antioxidant activity was determined by testing free radical-scavenging capacity (DPPH assay). Moreover, the disc diffusion method was used to analyze the antifungal activity of GMEO in in vitro conditions. The results demonstrate that the Citrus reticulata EO consisted of α-limonene as the most abundant component (71.5%), followed by γ-terpinene (13.9%), and β-pinene (3.5%), and it displayed the weak antioxidant activity with the value of inhibition 5.6 ±0.7%, which corresponds to 103.0 ±6.4 µg TEAC.mL-1. The findings from the GMEO antifungal activity determination revealed that values for the inhibition zone with disc diffusion method ranged from 0.00 ±0.00 (no antifungal effectiveness) to 5.67 ±0.58 mm (moderate antifungal activity). Finally, exposure of Penicillium strains growing on bread to GMEO in vapor phase led to the finding that 250 μL.L-1 of GMEO exhibited the lowest value for mycelial growth inhibition (MGI) of P. expansum (-51.37 ±3.01%) whose negative value reflects even supportive effect of the EO on the microscopic fungus growth. On the other hand, GMEO at this concentration (250 μL.L-1) resulted in the strongest inhibitory action (MGI: 54.15 ±1.15%) against growth of P. chrysogenum. Based on the findings it can be concluded that GMEO in the vapor phase is not an effective antifungal agent against the growth of P. expansum inoculated on bread; however, its antifungal potential manifested against P. chrysogenum suggests GMEO to be an appropriate alternative to the use of chemical inhibitors for bread preservation.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Somayeh Razmavar ◽  
Mahmood Ameen Abdulla ◽  
Salmah Binti Ismail ◽  
Pouya Hassandarvish

This study was based on screening antibacterial activity of the ethanol extract ofBaeckea frutescensL. against MRSA clinical isolates, analyzes the potential antibacterial compound, and assesses the cytotoxicity effect of the extract in tissue culture. Leaves ofBaeckea frutescensL. were shade dried, powdered, and extracted using solvent ethanol. Preliminary phytochemical screening of the crude extracts revealed the presence of alkaloids, flavonoids, steroids, terpenoids, phenols, and carbohydrates. The presence of these bioactive constituents is related to the antibacterial activity of the plant. Disc diffusion method revealed a high degree of activity against microorganisms. The results confirm thatBaeckea frutescensL. can be used as a source of drugs to fight infections caused by susceptible bacteria.


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