scholarly journals Muscodor sp. IBRL OS-94, A Promising Endophytic Fungus of Ocimum sanctum with Antimicrobial Activity

2020 ◽  
Vol 27 (2) ◽  
pp. 268-280
Author(s):  
Mohd Taufiq Mat Jalil ◽  
Nabila Husna Hairudin ◽  
Darah Ibrahim

Background: An endophytic fungus, Muscodor sp. IBRL OS-94 isolated from the leaf of Ocimum sanctum was believed to possess significant antimicrobial activity and several assays were carried out to evaluate its pharmaceutical potential. Methods: Agar plug diffusion and the disk diffusion assays were performed to evaluate the antimicrobial activity of the fungal extract. Also, the broth microdilution assay was done to investigate the minimum inhibitory concentration (MIC) of the fungal extract. Meanwhile, the scanning electron microscope (SEM) was employed to observe the structural degeneration of the microbial cells treated to the extract. Results: The results revealed that fungal isolate showed favorable antimicrobial activity through agar plug diffusion assay and the disk diffusion assay demonstrated that most of the test microorganisms were susceptible to extracellular extract compared to extracellular extract. As for the MIC and MLC values, the extracellular fungal extract exerted a bactericidal/fungicidal effect against all five Gram-positive bacteria, four Gram-negative bacteria, one yeast, and none of the test fungi. Meanwhile, the intracellular fungal extract exhibited bactericidal/fungicidal activity against three Gram-positive bacteria, one Gram-negative bacterium, and one yeast. The structural degeneration study via SEM revealed that various cell abnormalities including severe damage to the cell wall which led to microbial cell death. Conclusion: The present study suggests the fungal extract from Muscodor sp. IBRLOS-94 as an antimicrobial agent.

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Mashooq Ahmad Bhat ◽  
Mohamed A. Al-Omar ◽  
Ahmed M. Naglah ◽  
Abdul Arif Khan

A series of pyrazoles derived from the substituted enaminones were synthesized and were evaluated for antimicrobial activity. All the compounds were characterized by the spectral data and elemental analysis. The synthesized compounds were initially screened for their antimicrobial activity against ATCC 6538, NCTC 10400, NCTC 10418, and ATCC 27853. During initial screening, compounds (P1, P6, and P11) presented significant antimicrobial activity through disc diffusion assay. These compounds were further evaluated for antimicrobial activity at different time points against Gram-positive and Gram-negative bacteria and presented significant activity for 6 hours. The activity was found to be greater against Gram-positive bacteria. In contrast at 24 hours, the activity was found only against Gram-positive bacteria except compound (P11), showing activity against both types of bacteria. Compound (P11) was found to have highest activity against both Gram-positive and Gram-negative bacteria.


2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Chitra Jeyaraj Pandian ◽  
Rameshthangam Palanivel ◽  
Solairaj Dhanasekaran

Antimicrobial efficacy of nickel nanoparticles synthesized using leaf extract of Ocimum sanctum (NiGs) was investigated against pathogenic Gram-negative (E. coli, K. pneumoniae, and S. typhi), Gram-positive (B. subtilis, S. epidermidis) bacteria and fungi (C. albicans, C. tropicalis, A. fumigatus, A. clavatus, and A. niger). 100 µg/mL NiGs showed maximum antimicrobial activity against tested pathogens compared to leaf extract and antibiotics. E. coli (25 mm) and C. albicans (23 mm) exhibited higher zone of inhibition at 100 µg/mL NiGs. MIC, MBC, and MFC values of NiGs against all tested pathogens ranged between 25 and 50 µg/mL. Growth of bacterial and fungal cells (105 cfu/mL) was completely inhibited at 50 µg/mL NiGs. E. coli and C. albicans have showed strong antimicrobial activity with 81% and 50% reactive oxygen species (ROS) production, 30 and 16 µg/mL protein leakage, and 95 and 82 U/L LDH leakages, respectively. Gram-negative bacteria and Candida species showed more sensitivity to NiGs at all concentrations tested (25–100 µg/mL) than Gram-positive bacteria and Aspergillus species, respectively. Microbial growth in the presence of NiGs and ascorbic acid confirmed the involvement of ROS in antimicrobial activity. Hence, NiGs induced ROS generation was attributed to the protein and LDH leakage from microbial membranes.


2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Eti Nurwening Sholikhah ◽  
Maulina Diah ◽  
Mustofa ◽  
Masriani ◽  
Susi Iravati ◽  
...  

Pycnarrhena cauliflora (Miers.) Diels., local name sengkubak, is one of indigenous plants from West Kalimantan that has been used as natural flavor. Pycnorrhena cauliflora is one of species of Menispermaceae family which is rich in bisbenzylisoquinoline alkaloids. This alkaloids are known to have various biological activities including antiprotozoal, antiplasmodial, antifungal and antibacterial activities. This study aimed to investigate antimicrobial activity of  the P. cauliflora (Miers.) Diels. methanolic extracts against gram-positive and gram-negative bacteria. The methanolic extract of P. cauliflora (Miers.) Diels., root, leaf and stem were prepared by maceration. The disk-diffusion method was then used to determine the antimicrobial activity of the extracts against Streptococcus pyogenes, S. mutants, Staphylococcus aureus, S. epidermidis, Salmonella typhi, Shigella flexneri, Pseudomonas aeruginosa and Escherichia coli after 18-24 h incubation at 37 oC. Amoxicillin was used as positive control for gram-positive bacteria and ciprofloxacin was used as gram-negative bacteria. The inhibition zones were then measured in mm. Analysis were conducted in duplicates. The results showed in general the methanolic extracts of P. cauliflora (Miers.) Diels. root (inhibition zone diameter= 10-23 mm) were more active than that leaf (0-15 mm) and stem (0-17 mm) extracts against gram-positive bacteria. The zone inhibition diameter of amoxicillin as positive control was 8-42 mm. In addition, the methanolic extracts of P. cauliflora (Miers.) Diels. root (12-17 mm) were also more active than that leaf (0-12 mm) and stem (0-12 mm) extracts against gram-negative bacteria. The zone inhibition diameter of ciprofloxacin as positive control was 33-36 mm. In conclusion, the methanolic extract of P. caulifloria (Miers.) Diels. root is the most extract active against both gram-positive and gram-negative bacteria. Further study will be focused to isolate active compounds in the methanolic extract of the root.


2016 ◽  
Vol 78 (3-2) ◽  
Author(s):  
Nor Syafawani Sarah Md Saad ◽  
Nik Ahmad Nizam Nik Malek ◽  
Chun Shiong Chong

The aim of this research was to determine the antimicrobial activity of kaolinite modified with antimicrobial compounds against Gram positive and Gram negative bacteria. Copper kaolinite (Cu-kaolinite) was prepared by loading raw kaolinite with copper nitrate trihydrate (CuNO3) while surfactant modified Cu-kaolinite (SM-Cu-kaolinite) was prepared by adding cationic surfactants hexadecyltrimethyl ammonium (HDTMA) on Cu-Kaolinite. Samples was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analyzer. The antimicrobial activity of the samples was tested against Gram negative bacteria (Escherichia coli ATCC 11229 and Pseudomonas aeruginosa ATCC 15442), and Gram positive bacteria (Staphylococcus aureus ATCC 6538 and Enterococcus faecalis ATCC 29212) through disc diffusion technique (DDT) and minimum inhibition concentration (MIC). The results showed that the antimicrobial activity of Cu-kaolinite increased after modified with HDTMA due to the synergistic effects of Cu ions and HDTMA molecules on the kaolinite. The antimicrobial activity for surfactant modified Cu-kaolinite was greater for Gram positive bacteria compared to Gram negative bacteria. In conclusion, the attachment of HDTMA on Cu-kaolinite contributed to the enhanced antimicrobial activity against wide spectrum of bacteria (Gram positive and Gram negative bacteria).


2011 ◽  
Vol 8 (3) ◽  
pp. 1430-1437 ◽  
Author(s):  
S. S. Deo ◽  
F. Inam ◽  
R. P. Mahashabde

The antimicrobial activity of crude methanolic and aqueous extracts ofOcimum sanctumandOcimum kilimandsacharicumagainst gram positive, gram negative and antifungal activity was evaluated to find the zone of inhibition and to set a HPLC profile or fingerprint of these extracts. The crude methanolic extract ofOcimum sanctumshowed strong antimicrobial activity againstS.aureusandC. albicansand moderate activity againstE. coliandB. subtilis. The crude methanolic extract ofOcimum kilimandsacharicumshowed strong antimicrobial activity againstS. aureus, E. coliandC. albicansat higher concentration, same as that shown by the standard forC. albicans. It showed moderate activity againstB. subtilis. The crude aqueous extracts of Ocimum sanctum showed strong antimicrobial activity againstS.aureusand moderate against others. Whereas the crude aqueous extracts ofOcimum kilimandsacharicumshowed moderate activity against the gram positive and gram negative organisms and strong activity againstC. albicansat higher concentration, same as that shown by the standard forC. albicans.


Antibiotics ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 238 ◽  
Author(s):  
Yamil Liscano ◽  
Constain H. Salamanca ◽  
Lina Vargas ◽  
Stefania Cantor ◽  
Valentina Laverde-Rojas ◽  
...  

Recently, resistance of pathogens towards conventional antibiotics has increased, representing a threat to public health globally. As part of the fight against this, studies on alternative antibiotics such as antimicrobial peptides have been performed, and it has been shown that their sequence and structure are closely related to their antimicrobial activity. Against this background, we here evaluated the antibacterial activity of two peptides developed by solid-phase synthesis, Alyteserin 1c (WT) and its mutant derivative (ΔM), which shows increased net charge and reduced hydrophobicity. These structural characteristics were modified as a result of amino acid substitutions on the polar face of the WT helix. The minimum inhibitory concentration (MIC) of both peptides was obtained in Gram-positive and Gram-negative bacteria. The results showed that the rational substitutions of the amino acids increased the activity in Gram-positive bacteria, especially against Staphylococcus aureus, for which the MIC was one-third of that for the WT analog. In contrast to the case for Gram-positive bacteria, these substitutions decreased activity against Gram-negative bacteria, especially in Escherichia coli, for which the MIC was eight-fold higher than that exhibited by the WT peptide. To understand this, models of the peptide behavior upon interacting with membranes of E. coli and S. aureus created using molecular dynamics were studied and it was determined that the helical stability of the peptide is indispensable for antimicrobial activity. The hydrogen bonds between the His20 of the peptides and the phospholipids of the membranes should modulate the selectivity associated with structural stability at the carboxy-terminal region of the peptides.


2017 ◽  
Vol 27 (5) ◽  
pp. 26 ◽  
Author(s):  
Nehad A. Taher

About 10 isolates of Pediococcus sp were isolated from different cheese made in Iraq, These isolates were identified morphologically and biochemically and Api20 kit, thus there was only 6 isolate were identified as Pediococcus pentosaceus (60%).In this study, we investigate, the effect of crude Bacteriocin from Pediococcus pentosaceus on 30 clinical isolates (5 E.coli, 5 Klepsiella pneumoniae, 5 Staphylococcus aureus, 5 Pseudomonas aeroginosa, 5 Bacillus subtilis, 5 Candida albicans). The protein concentration of this Bacteriocin was measured 67mg\ml by Bradford method and used as (1:2) by vol during the measuring the antimicrobial activity against the above clinical isolates by two methods wells and  agar plug assay. The results showed that  the inhibitory activity of this Bacteriocin was higher by wells method than agar pluq assay against Gram–positive bacteria or Gram-negative bacteria and yeast under this study.


Author(s):  
Shaileshkumar C Kotval ◽  
Kokila A Parmar

In this study, Mitragyna parvifolia plant bark an aqueous extract which provides cost-effective, eco-friendly process, less time consuming, an environmentally benign, easy and proficient way for the synthesis of copper nanoparticles. Mitragyna parvifolia plant bark was collected from virpur hills forest area. The Mitragyna parvifolia plant bark extract was prepared in de-ionised water and used for the green synthesis of copper nanoparticles. The color change of the solution dark brown from pale yellow colored, this confirms that there is a formation of copper nanoparticles. The green synthesised copper nanoparticles were characterized by UV-Visible spectroscopy, FT-IR, XRD, SEM, TEM and their antimicrobial activity was investigated. From UV-Visible spectrophotometer result was confirmed the reduction of copper sulphate to copper nanoparticles. FTIR analysis was confirmed the bending vibrations and stretching bonds present in the sample. Spherical shape was finding out by XRD and the size of the particle was analyzed with the help of Scanning Electron Microscopy. The antibacterial activity experiment against Escherichia coli gram-negative and Bacillus subtilis gram-positive bacteria by agar well method and the maximum zone of inhibition was higher in gram-positive bacteria compared to gram-negative bacteria. The green synthesised copper nanoparticles proved to be potential candidates for medical application antimicrobial activity is highly essential.


1989 ◽  
Vol 52 (9) ◽  
pp. 665-667 ◽  
Author(s):  
R. S. FARAG ◽  
Z. Y. DAW ◽  
F. M. HEWEDI ◽  
G. S. A. EL-BAROTY

Six spice essential oils (sage, rosemary, caraway, cumin, clove, and thyme) and their basic ingredients were tested for their inhibitory effect against 3 strains of Gram-negative bacteria, 4 strains of Gram-positive bacteria, one acid fast bacterium, and one yeast. Preliminary screening of antimicrobial activity of the essential oils was done using the filter paper disc agar diffusion method. The minimum inhibitory concentration for each essential oil against various micro-organisms was also measured. Very low concentrations (0.25 – 12 mg/ml) of the various essential oils were sufficient to prevent microbial growth. The data show that Gram-positive bacteria were more sensitive to the antimicrobial compounds in spices than Gram-negative. The inhibition zones of different microbial growth produced by various essential oils were similar to those produced by their basic compounds. Thyme and cumin oils possessed very strong antimicrobial activity compared with the other essential oils. There was a relationship between the chemical structures of the most abundant compounds in the essential oils under investigation and the antimicrobial activity.


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