Effect of some natural plant extracts against gram negative bacteria in Njran Area, Saudi Arabia

Background. Emergence of pathogenic bacteria carrying β-lactamase-resistant determinants has become a major health problem in the hospital setting. The study aimed to determine antibiotic-resistant patterns and frequency of extended-spectrum β-lactamase- (ESBL-) producing Gram-negative bacteria (GNB) and AmpC β-lactamase-producing GNB. Methodology. A prospective cross-sectional study was conducted during a period from September 2017 to August 2018 at King Abdullah Hospital, Bisha Province, Saudi Arabia. GNB (n = 311) were recovered from patients’ clinical specimens including sputum, urine, wound pus, blood, tracheal aspirates and high vaginal swabs, umbilical discharge, eye discharge, and cerebrospinal fluids. Isolates were identified by the Phoenix identification system. Antimicrobial susceptibility was tested by the Kirby–Bauer disk procedure. Phenotypic characterization of ESBLs and AmpC β-lactamases was performed utilizing the double-disk synergy test and inhibitor-based method, respectively. Associations with outcome measures were determined by simple descriptive statistics and a chi-square test. Results. Out of 311 GNB isolates, the frequency of ESBL and AmpC β-lactamase producers was 84 (27%) and 101 (32.5%), respectively. Klebsiella pneumoniae and Escherichia coli were common ESBL producers. AmpC β-lactamases predominate among Acinetobacter spp. and Pseudomonas aeruginosa. Coproduction of ESBLs and AmpC β-lactamases was found in 36 (11.6%) isolates, with very close relative frequencies among K. pneumoniae, Acinetobacter spp., and P. aeruginosa. β-Lactamase producers were predominantly found in the surgical department (56.5%) and ICUs (44.2%). ESBL producers revealed high resistance for cefuroxime (96.4%), cefotaxime (92.9%), and trimethoprim/sulfamethoxazole (90.5%). The resistance rates were significantly higher among ESBL producers than nonproducers for cephalosporins (p<0.001), amoxicillin/clavulanate (p<0.001), piperacillin/tazobactam (p=0.010), nitrofurantoin (p=0.027), aztreonam (p<0.001), ciprofloxacin (p=0.002), and trimethoprim/sulfamethoxazole (p<0.001). Significantly higher (p<0.05) resistance rates were observed among AmpC β-lactamase producers than nonproducers for all tested antibiotics. Conclusions. This finding showed a high prevalence of ESBL- and AmpC β-lactamase-producing GNB in our hospital. Quality control practice and routine detection of β-lactamase producers before deciding on antibiotic therapy are advocated.

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The Antibacterial Activity of Catunaregam tomentosa Against Selected Gram-Positive and Gram-Negative Bacteria

Asian Journal of Medicine and Biomedicine ◽

10.37231/ajmb.2021.5.s1.450 ◽

2021 ◽

Vol 5 (S1) ◽

pp. 34-38

Author(s):

Nor Aleesa Ali ◽

Wan Amalina Wan Mamat ◽

Syed Ahmad Tajudin Tuan Johari ◽

Muhammad Yusran Abdul Aziz ◽

Ahmad Syibli Othman

Keyword(s):

Antibacterial Activity ◽

Plant Extracts ◽

Bacterial Infections ◽

Scientific Basis ◽

Diffusion Method ◽

Antibacterial Drug ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Value Evaluation

Catunaregam tomentosa is a plant from Rubiaceae family that is used in traditional medicine for the treatment of stomatitis and ulcers due to bacterial infections. Besides, it also helps in the treatment of oliguria and dysuria. Indiscriminate use of commercial antibacterial medicines had led to the search for novel antibacterial drugs. Since for ages medicinal plants have been used to treat bacterial infection, so they can be excellent sources of the novel antibacterial drug. To evaluate the scientific basis of the use of plant, antibacterial activity leaves extract of C.tomentosa was investigated against selected Gram-positive and Gram-negative bacteria. The study also investigated the effect of pH on its antibacterial activity. Antibacterial activity of the plant extracts was evaluated against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa by using the disc diffusion method at 100mg/mL concentration. Extracts of C. tomentosa inhibit the activity of S. aureus but do not inhibit the activity of Gram-negative bacteria. Minimum inhibitory concentration (MIC) was also determined against S. aureus at concentration 100, 50, 25, 12.5, 6, 3, 1.5, 0.75 and 0.395mg/mL and 3mg/mL were the MIC value. Evaluation on the effect of different pH on antibacterial activity of plant extracts shows that the activity of the plant extracts does not affect when treated with acidic pH but increased at alkaline pH. Based on the present finding, C. tomentosa leaves extract have the potential to be a viable candidate in the discovery of a natural antibacterial agent against S. aureus infections. This study provides scientific knowledge to further determine the antibacterial values of C. tomentosa extracts.

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Antibacterial activity in the leaves of seven bitter medicinal plants of Bangladesh

Journal of Bio-Science ◽

10.3329/jbs.v18i0.8788 ◽

1970 ◽

Vol 18 ◽

pp. 128-133 ◽

Cited By ~ 1

Author(s):

MTH Molla ◽

MS Ahsan ◽

MT Alam ◽

ME Haque

Keyword(s):

Antibacterial Activity ◽

Bacillus Subtilis ◽

Medicinal Plants ◽

Plant Extracts ◽

Salmonella Typhi ◽

Antimicrobial Activities ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Ethanolic Extracts

Context: Development of resistance in human pathogens against conventional antibiotic necessitates searching indigenous medicinal plants having antibacterial property. Seven medicinal plants used actively in folklore, ayurvedic and traditional system of medicine were selected for the evaluation of their antimicrobial activity for this study. Objectives: Evaluation of the effectiveness of some medicinal plant extracts against four Gram-positive and five Gram-negative bacteria. Materials and Methods: The antibacterial activity of the crude ethanolic extracts obtained from the leaves of seven medicinal plants; viz., Andrographis paniculata, Catharanthus roseus, Adhatoda vasica, Vitex vegundo, Aloe vera, Flacortia ramontchi and Nyctanthes arbortristis were tested against nine bacteria at concentrations of 300-, 400- and 500 μg/ml. Standard antibiotic disc kanamycin (30μg/ml) was used for comparison. The minimum inhibitory concentration (MIC) of ethanolic extracts of the leaves of these medicinal plants were determined by testing the extracts on four Gram-positive and five Gram-negative bacteria by serial tube dilution method. Results: All the extracts have notable antimicrobial activities against the test organisms. The ethanolic extracts of the leaves showed the highest antimicrobial activities against Bacillus megaterium and Shigella dysenteriae for An. paniculata, Ad. vasica and Al. vera; Bacillus subtilis and Salmonella typhi for C. roseus and N. arbortristis; Staphylociccus aureus and Salmonella typhi for V. vegundo; and Bacillus subtilis and Shigella sonnei for F. ramontchi respectively. The extract of the plants had MIC values ranging from 32 to 128 mg/ml. All plant extracts showed no MIC against Shigella shiga and against Sarcina lutea only C. roseus showed MIC 128 mg/ml. Conclusion: The results revealed that the ethanolic extracts of the plants under present investigation have notable antimicrobial activities. Keywords: medicinal plants; antimicrobial screening; MIC; bacteria. DOI: http://dx.doi.org/10.3329/jbs.v18i0.8788 JBS 2010; 18(0): 128-133

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